UWorld NCLEX Cram EXAM 1 2023/2024

UWorld NCLEX Cram EXAM 1 2023/2024 UWorld NCLEX Cram EXAM 1 2023/2024 Terms in this set (2000) Lambert Eaton Myasthenic Syndrome Lambert-Eaton Myasthenic Syndrome is a neuromuscular disorder presenting with proximal muscle weakness (trouble getting up the stairs or getting up), cranial nerve involvement, and autonomic symptoms (like impotence). many patients also have small cell lung cancer classically. Narcolepsy rare neurolgoic disorder characterized by episodes or irresisitible, refrehsing sleep during the daytime and usually one or more REM Sleep-related phenomena such as cataplexy, hypnogogic/hypnopomipic hallucinations, and sleep paralysis. HIV associated Toxoplasmosis The finding of multiple ring-enhancing lesions in an HIV patient is most likely due to.... Immune memory to Influenza Virus most importantly to prevent infection are anti- hemagglutinin antibodies. Passive agression The expression of angry feelings in a non- confrontational manner Anal fissure a tear in the lining of the anal canal distal to the dentate line that occurs most often in the posterior midline (poor perfusion here). Patients often complain of severe tearing pain with bowel movements. Associated with low-fiber diets and constipation. Hemolytic Uremic Syndrome common cause of acute renal failure in children. It is characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Most cases develop following diarrheal illnes caused by Shiga toxin-producing organisms (E.coli O157:H7 and shigella dysenteriae). Anaerobic conditions and NAD+ Under anaerbic conditions, NADH transfers protons to pyruvate to form lactate and to regenerate NAD+. NAD+ is required for glycolysis to occur. Aortic coarctation in a child/young adult presents with lower extremity claudication (pain an cramping with exercise), blood pressure discrepancy between the upper and lower extremities, and delayed or diminished femoral pulses. Turners syndrome (45 X) is associated with this condition in up to 10% of cases. Attributable Risk Percent in the exposed group represents the excess risk in the epxosed population that can be attributed to the risk factor. It can be easily derived form the relative risk using the formula ARP = 100 x (RR-1)/RR Two Sample T test a statistical method used to compare the means of 2 groups of subjects. If p 0.05, the null is rejected and the means are different. Type I Collagen The most abundant collagen. It is present in bones and tendons. It eventually replaces type III collagen after an MI as type I collagen forms a mature scar. Pericardial Tamponade Post-MI the triad of muffled heart sounds, elevated jugular venous pressure, and profound hypotension indicated pericardial tamponade. Rupture of the ventricular free wall as a consequence of an acute transmural MI can cause tamponade. Rupture typically occurs 3-7 days after onset of total ischemia, when coag necrosis, neutrophil infiltration, and enzymatic lysis of connective tissue may have sufficiently weakened the infarcted myocardium. Amino Acid tRNA synthetase Responsible for loading tRNA with the right AA. It is highly accurate, but if incorrect and not proofread, the wrong amino acid will be attached to the growing peptide chain. Vitamin B12 (cobalamin) Is the exception to the rule where other water- soluble vitamins are rapidly depleted without dietary intake. Hepatic stores of vitamin B12 may last up to several years. Ubiquitin ligases NCLEX Cram UWorld 1 recognizes specific protein substrates and attach a ubiquitin tag. The proteins are then degraded to an appropriate size and coupled with the major histocompatibility I protein complex in the ER so Ubiquitin a protein that undergoes ATP-dependent attachment to other proteins, labeling them for degradation. Impairment of the ubiquitin- proteasome system may contribute to neurodegenerative disorders like Parkinson's and Alzheimer's. Pleiotrophy describes instances where multiple phenotypic manifestations result from a single genetic mutation. Most syndromic genetic illnesses exhibit pleiotrophy. Femoral Nerve Lesions (L2-L4) can occur due to trauma, nerve compression, stretch injury, or ischemia. Patients develop weakness of the quadriceps muscle (trouble going upstairs or knee buckling), loss of the patellar reflex, and loss of sensation over the anterior and medial thigh and leg. Femoral Hernia inferior to the inguinal ligament (unlike the inguinal hernias), lateral to the pubic tubercle, and medial to the femoral vein. They can present with groin discomfort or manifest as a bulge in the upper thigh. Incarceration and strangulation are common complications of femoral hernias- would think N/V and fever. More common in women than men. Radial Head subluxation (nursemaid's elbow) NCLEX Cram UWorld 1 results form sudden traction on the outstretched and pronated arm of a child. Affected children are usually in little distress unless attempts are made to move the elbow from their extended and pronated position. The annular ligament is torn and displaced Bone-specific alkaline phosphatase Reflects osteoblastic activity CFTR Mutation in CF and What it does In respiratory and gastric glands, impaired functioning of the CFTR transmembrane protein reduces luminal chloride secretion and increases sodium and net water absorption, resulting in dehydrated mucus and a more negative transepithelial potential difference. However, in sweat glands there is reduce luminal salt absorption leading to production of hypertonic sweat with high chloride content. Lobar Pneumonia Pathology inflammation involves an entire lobe of the lung. The course of the disease includes four morphologic stages: congestion (Vascular dilation, alveolar exudate contains bacteria), red hepatizaiton (red, firm lobe with alveolar exudate containing erythrocytes, neutrophils, and fibrin), gray hepatization (gray, pale firm lobe with same but RBC's disintegrate), and resolution (back to normal) Hypocalcemia by blood transfusion Patients who receive the equivalent of more than one body blood volume over a period of 24 hours may develop elevated plasma levels of citrate (substance added to stored blood), which can chelate calcium causing serum levels to reduce and thus paresthesias can ensue. NCLEX Cram UWorld 1 Kidney embryology The ureteric bud ultimately gives rise to the collecting system of the kidney, including the collecting tubules and ducts, major and minor calyces, renal pelvis, and ureters. The metanephric mesoderm (blastema) gives rise to glomeruli, Bowman's space, proximal tubules, the loop of Henle, and distal convoluted tubule. Pyelonephritis and Vesicoureteral reflux For a UTI to get all the way to pyelonephritis, vesicoureteral reflux is almost always necessary because we normally have ways to prevent this. Gram-negative rods like E.coli, Klebsiella, and proteus are the most common players. Blastomyces Dermatitidis One of the dimorphic fungi. Seen in the Ohio and Mississippi River Vallyes,Great Lakes region. Found in the soil. Can cause pulmonary pneumonia. at 25 degrees: branching hyphae. Large cell single bud yeast at body temperature/biopsy. Dimorphic fungi grow as molds at 25-30 degrees C as as yeast at body temperature (35-37). Medically importnat dimporphic fungi include Sporothrix, Coccidiodies, Histoplasma, Blastomyces, and Paracoccidioides. C.diff Contact Precautions hand washing with soap and water (sanitizer is not sufficient), gown, and gloves Thayer-Martin VCN Medium Can be used to isolate Neisseria organisms by culture. It is selective media and inhibits growth of contaminants like Gram +, gram negatives besides Neisseria, and fungi Poststreptococcal glomeruloneprhitis periorbital edema, mild to moderate hypotension, and hematuria in a child 2-4 weeks after streptococcal infection (skin or pharynx). On EM, on the epithelial side of the glomerular basement membrane, sub epithelial humps composed of immune complexes of IgG, IgM, and C3 can be seen. Transposition of the Great Arteries An echocardiogram showing an aorta lying anterior to and to the right of the pulmonary artery is diagnostic of transposition of the great arteries. TGA results from failure of the fetal aorticopulmonary septum to spiral normally during septation of the trucus arteriosus, presenting lifethreatening cyanosis at birth. Machine-like murmor patent ductus arteriosus This, septal defect, or patent foramen ovale would be necessary for survival with a TGA. Cancer Death in Women Breast is the most common cancer but mortality is relatively low whereas lung is less common but mortality is high. Colon comes after these two. Lung is the most common cancer death in women. Germinal Centers The primary immune response to new antigen initially results in plasma cells that only produce IgM. Isotype switching occurs later in the germinal centers of lymph nodes and this requires the interaction of CD40 receptor on B cells with CD40L on activated T cells. IgG then becomes the main serum immunoglobulin in the secondary immune response. NK cells recognize and kill cels with decreased MHC Class I antigen cell surface expression, such as virus- infected cells and tumor cells. They are large lymphocytes that contain perforins (cut open cell) and granzymes in cytoplasmic granules (induce apoptosis after entering the perforin). Alzheimer's disease biochemistry decreased levels of acetylcholine in the nucleus basalis of Meynert hippocampus. Diminshed choline acetyltransferase in these structures is the cause (hence we treat with meds that prevent breakdown of acetylcholine) Indicators of Liver damage/function Increases Aspartate amintotransferase (AST) and alanine aminostransferase (ALT) are indicators of hepatocellular damage, while increased alkaline phosphatase and gamma-gltamyl transpeptidase indicate biliary injury. Serum albumin levels, bilirubin levels, and prothrombin time are reflective of liver function and are of greatest prognostic importance. Relative Risk Reduction RRR = (absolute risk (control)- absolute risk (treatment))/absolute risk (control) NCLEX Cram UWorld 1 Meningococcal Lipooligosaccharide (LOS) responsible for many of the observed toxic effects in meningitis and meningococcemia for the gram- negative diplococcus Neisseria meningitidis. Blood levels of this endotoxin correlate with morbidity and mortality Acute Cholecystitis Most commonly caused by gallstones obstructing the cystic duct. Dx can be made by identifying signs of gallbladder inflammation (wall thickening, pericholecystic fluid) on ultrasonography. When ultrasound is inconclusive, nuclear medicine hepatobiliary scanning can be used to asses cystic duct patency and clinch the dx. CGD Results from a genetic defect in NADPH oxidase. Normally, NADPH oxidase kills microbes wihtin neutorphil and macrophages. Increased susceptibility to catalase-positive organisms: Staph Aureus, Burkholderia cepacia, Serratia marcescens, Nocardia, and Aspergillus. Elevated Serum Aldosterone levels can manifest as hypertension, hypokalemia, and muscle weakness. Increased levels of both renin and aldosterone are indicative of secondary hyperaldosteronism, which can be caused by renovascular disease, malignant hypertension, and renin-secreting tumors. Vasopress/Desmopressin Causes A V2 receptor-mediated increase in water and urea permeability in the inner medullary collecting duct. The resulting rise in urea reabsorption (decreased urea clearance) enchances the medullary osmotic gradient, allowing the production of maximally concentrated urine. Nephron dynamics The concentrations of PAH, creatinine, inulin, and urea increase as fluid runs along the proximal tubule, while the concentrations of bicarbonate, glucose, and amino acids decrease. Scaphoid injury A fall onto an outstretched hand can easily cause fracture to scaphoid bone. Tenderness is seen in the anatomical snuff box. The scaphoid bone is vulnerable to avascular necrosis due to its tenuous blood supply. Patent ductus arteriosus It is derived from the sixth embryonic structure. A PDA causes left to right shunting of the blood and can be heard as a machine like murmur or a thrill over the left infracalvicular region. Indomethacin can be used to close a PDA in premature infants, but surgery is required for older patients. Epistaxis commonly caused by trauma in children in the anterior nasal septum containing Kiesselbach plexus. The ethmoidal, spenoplalatine, and superior labial arteries all anastomose in this region. Optic tract lesion can produce a contralateral homonymous hemianopia and a relative afferent pupillary defect (Marcus Gunn pupil) in the pupil contralateral to the tract lesion. See in the swinging flashlight test. Vaginal Agenesis/Mullerian aplasia have no upper vagina and variable uterine development. They are XX females with normal ovaries and secondary sexual characteristics (estrogen still released). Systemic Mastocytosis characterized by abnormal proliferation of mast cells and increased histamine secretion. This increases the production of gastric acid by parietal cells. Gastric acid hyper secretion therefore commonly occurs. Bacterial Vaginosis NCLEX Cram UWorld 1 caused by a disruption of vaginal bacterial flora and characterized by fishy-smelling thin grayish vaginal discharge and clue cells (epithelial cells covered with gram-negative rods). Metronidazole and Pyrdidoxine (Vit B6) Transanimation reactions need this (alpha keto acid to become an amino acid) Primary Biliary Cirrhosis a chronic liver disease characterized by autoimmune destruction of the intrahepatic bile ducts and cholestasis (elevated alk phos). The condition is most common in middle-aged women, with severe pruritis usually being the first symptom reported. Can be associated with Sjogren's syndrome and other autoimmune diseases. Thiamine (B1) deficiency leads to diminished ability of cerebral cells to utilize glucose (hence wernicke's encephalopathy where ophtlamoplegia, ataxia, and confusion result). Pyruvate dehydrogenase, alphaketoglutarate dehydrogenase and transketolase all need B1 to function. Thiamine deficiency can be diagnosed by measuring erythrocyte transketolase activity. NCLEX Cram UWorld 1 The Schilling test helps differentiate dietary B12 deficiency from pernicious anemia and malabsorption as caused of megaloblastic anemia. In dietary deficiency, oral radiolabeld vit B12 is absorbed in the gut and excrete din the kidneys at normal amounts. Major depressive disorder consists of a 2 weeks period of 5 of the following: depressed mood, loss of interest, sleep disturbance, appetite disturbance, loss of energy, psychomotor agitation or retardation, impaired concentration, guilt, and suicidal thoughts. aka SIG E CAPS Pyruvate dehydrogenase deficiency Must prevent the conversion of pyruvate to lactic acid since can't go to acetyl CoA (causes acidosis otherwise). Lysine and Leucine are exclusively ketogenic AA's and would not increase the blood lactate levels. when trying to avoid lactate, use lysine and leucine. Giant Cell Arteritis/temporal arteritis Cell-mediated immunity is the primary problem. The production of cytokines, in particular interleukin-6, are important drivers and correlate with severity. Characterized by headaches, visual symptoms, elevated ESR, and visible temporal artery Contractile mechanism in skeletal muscle Relies on proteins (myosin II, actin, tropomyosin, and troponin) as well as calcium ions form the sarcoplasmic reticulum. Prinzmetal's agina characterized by episodic, transient attacks of coronary vasopasm, producing temporary ST elevations typically at night. Ergonovine causes the spasm and can aid in diagnosis treated with vasodialting nitrates adn calcium channel blockers. Cryoglubulinemia Cutaneous manifestations and associated with Hep C The Blood Brain Barrier NCLEX Cram UWorld 1 formed by tight junctions between nonfenestrated capillary endothelial cells that prevent the paracellular passage of fluid and solutes. Transcellular moment must occur for substance to Caudal Regression Syndrome patient is born with agenesis of the sacrum and occasionally lumbar spine and experiences flaccid paralysis of the legs and urinary incontinence. Frequently related to poorly controlled maternal diabetes. Positively Skewed Distribution The mean is the most shifted in the positive direction, followed by the median than the mode Prospective cohort study select a group of individuals, determine their exposure status, and then follow them over time to see if they develop the disease of interest. Candida infection in HIV localized defense against candida is performed by T cells, whereas systemic infection is prevented by neutrophils. For this reason, localized candidiasis is common in patients who have HIV, but neutropenic patients are more likely to have systemic form of disease. Candida albicans single-celled budding yeast with pseudohyphae (also germ tubes at certain rich serum) Achondroplasia Autosomal dominant (chance of inheritance to child of heterozygote is 50%) that results in gain of function of FGFR3 gene. Neisseria gonorrhoeae Can cause acute bacterial arthritis in sexually active young adults (assymetric polyarthritis). Synovial fluid should be notable for neutrophilic predominance and faculative intracellular organisms. Inflammation characterized by the passage of circulating inflammatory leukocytes into the inflamed tissue. The steps involved include margination, rolling, activation, tight adhesion, and crawling, and transmigration (this is where the neutrophil migrates out of the vasculature). When this process is knocked out in some way (rare genetic disorders), patients get recurrent skin infections, without pus formation, and delayed detachment of the umbilical cord. sickle cell anemia exertion dyspnea, pneumonia and resulting acute chest syndrome, and recurrent abdominal and bone pain are are clinical features of this disease. Results from a point mutation that causes valine substitution for glutamic acid in the sixth position of the b-globin chain. Cyanide poisoning rapid cutaneous flushing, tachypnea, headache, tachycarida with nausea/vomitting, confusion and weakness. Labs show severe lactic acidosis (remember it blocks oxidative phosphorylation) Propionyl CoA derived from the amino acids Valine, Isoleucine, Methionine, and Thr, odd-numbered fatty acids, and cholesterol side chains. Congenital deficiency of propionyl CoA carboxylase, the enzyme responsible for propionyl CoA to methylmalonyl CoA leads to developed of propionic acidemia. NCLEX Cram UWorld 1 Scotoma a visual field defect that occurs due to a pathologic process that involves part of the retina or optic nerve resulting in a discrete area of altered vision with surrounding normal vision. Lesions of the macula (macular degeneration, MS, diabetic retinopathy) can cause a central scotoma. Muscle contraction calcium is released from the sarcoplasmic reticulum and binds troponin C, thereby allowing the binding of actin to myosin. equilibrium potential when a specific ion channel opens, the respective ions will flow across the membrane in a direction that brings the resting membrane potential closer to that ion's equilibrium potential. Remember, Sodium is primarily extracellular with a equilibrium potential of +60mv, Potassium is primarily intracellular with an equilibrium potential of -90 mv, and chloride is priamrily extracellular with a membrane potential of -75 mv. indwelling central catheters Important but have increased the risk for bloodstream infections with orgs like S. Aureus. Down Syndrome NCLEX Cram UWorld 1 Clinical features include flat facies, epicanthal folds, oblique palpebral fissures and a single palmar crease. Congenital heart defects are seen in 50% of patients with this condition (endocardial cushion defects). Majority of cases are due to maternal Glycogen degradation and muscle contraction The two are synchronized due to release of sarcoplasmic calcium, which causes activation of phosphorylase kinase, thus stimulating glycogen phosphorylase to go ahead and commence glycogenolysis. Lesions of the glossopharyngeal nerve result in loss of loss of the gag reflex (afferent limb); loss of sensation in the upper pharanyx, posterior tongue, tonsils, and middle ear cavity; and loss of taste sensation on the posterior 1/3 of the tongue. The glossopharyngeal nerve exits out the jugular foramen (call 911) Von Willebrand Disease Patients often present with a life-long history of mucosal bleeding, including gingival bleeding, epistaxis, and/or menorrhagia. These patients have normal platelet levels but typically have a prolonged bleeding time due to impaired platelet functioning. Von Willebrand factor functions as a promoter of platelet adhesion at sites of vascular injury by binding platelet glycoproteins (GpIB) to sub endothelial collagen. Also carries factor VIII PCOS characterized by elevated LH levels, excess androgen production, and insulin resistance. Clinical features include obesity, menstrural irregularities, hirsutism, elarged ovaries, and an increased risk for diabetes mellitus and endometrial hyperplasia. Ecthyma gangrenosum a cutaneous necrotic disease associated with Pseudomonas bacteremia. These infectiosn are common in patients who a neutropenic (chemotherapy, are hospitalized, have burns, or indwelling catheters. Coccidioides immitis a dimorphic fungi endemic to southwestern United States (California, New Mexico, Arizona). It exists in the environment as a mold (with hyphae) that forms spores. These spores are inhaled and turn into spherules in the lungs (pneumonia). Avoidant Personality Disorder characterized by social inhibition, feelings of inadequacy, and fear of embarrassment and rejection. They often lack relationships out of fear, but key thing is that they desire them, unlike schizoid or scizotypal who are content on their own. occurs when the transverse portion of the Superior Mesenteric Artery duodenum is entrapped between the SMA and Syndrome aorta, causing symptoms of partial intestinal obstruction. Posterior cruciate ligament (PCL) prevents posterior displacement of the tibia relative to the femur. Look for posterior drawer test. Cholesterol gallstones Most common. Cholecystectomy is preffered, but hydrophilic bile acids can be used as medical therapy if surgery is not option to improve cholesterol solubility. DKA characterized by triad of polydipsia, polyruia, and a fruity odor to the breath and/or urine. It is assoicated with anion gap metabolic acidosis with compensatory respiratory alkalosis. aka low pH, low serum bicarb, and low PaCO2 CML disease of adults. Caused by translocation of 9;22 to form bcr-abl fusion protein, a tyrosine kinase that can be inhibited by imatinib (gleevec) Reed-sternberg cell The diagnostic cell of Hodgkin's lymphoma. RS can have abundant cytoplasm, bilobed or double nuclei, and inclusion-like eosinophilic nucleoli. Abetalipoproteinemia an inherited inability to synthesize apolipoprotien B, thus lipids absorbed in the small intestine cannot be transported by chylomicrons and therefore it builds up in enterocytes. Syringomyelia formation of a cavity (syrinx) in the cervical region of the spinal cord at the ventral white commissure, leading to bilateral loss of pain and temperature sensation at the arms and hands. It can extend to destruct the motor neurons of the ventral horns causing flaccid paralysis and atrophy of the intrinsic muscles of the hand You can see the exact timing of the opening and closing of the cardiac valves. Left Ventricular Pressure and Volume Curve Mycoplasma pneumonia causes walking pneumonia where patients experience a dry nagging cough, low-grade fever and malaise. Tell tale sign is chest x ray that looks much worse than how patient appears clinically. This organism requires cholesterol to grow. Trypanosoma cruzi causes achalasia (usually congenital). Can be caused by Trypanosoma Cruzi if from central or south america. It is a parasite transmitted by an insect. Its neurotoxin destroys the myenteric plexus. This incapacitates the lower esophageal sphincter, so that food gets stuck in the esophagus with esophageal dilatation above this. Vasectomy After vasectomy, viable sperm remain in the poriton of the vas deferens distal to the ligation. Patients can still have viable sperm in the ejaculate for 3 months/20 ejaculations at least. snRNPs synthesized by RNA polymerase II in the nucleus. They help to remove introns from the RNA transcript and are thus necessary for synthesis of mRNA (polyadenylaton at 3' end and capping at 5' end are also necessary neurocysticercosis relatively common cause of seizures in patients from central and south america. The organism isa parasite called Taenia Solum, the pork takeworm which is ingested from fecal matter of others. Hyperplasia of the submucosal glands in the duodenum Gastric acid is neutralized by bicarbonate from the submucosal aka Brunner glands of the duodenum as well as pancreatic duct secretions. Hyperplasia occurs with overproduction of gastric acid to neutralize. Lynch Syndrome NCLEX Cram UWorld 1 an autosomal dominant disease caused by abnormal nucleotide mismatch repair. Mutations in Adrenal Medullary Chromaffin Cells modified postganglionic sympathetic neurons (neuroendocrine) that release catecholamines into the blood stream in response to acetylcholine release by preganglionic sympathetic neurons. SCID (Severe Combined Immune Deficiency) life-threatening that presents when mom immunity wears off. It is characterized by combined T and B cell dysfunction. Characterized by severe viral and bacterial infections, mucocutateous Candidiasis, persistent, diarrhea and failure to thrive. Laboratory findings include absent T cells and hypogammaglobulinemia. Thymic shadow usually not present due to T cell deficiency. Polymerase Chain Reaction (PCR) used to amplify small fragments of DNA. It requires primers that are complimentary to the regions of DNA flanking the segment of interest. Cardiorespiratory response to excercise Increased HR, CO, and RR in order to balance increased total tissue O2 consumption and CO2 production. Arterial blood gas remains relatively constant, while venous PO2 is decreased and venous PCO2 is increased. Acute Hemolytic Transfusion Reaction is an antibody-mediated (type II) hypersensitivity reaction caused by preexisting anti-ABO antibodies that bind antigens on the new RBCs. Subsequent complement activation results in erythrocyte lysis, vasodilation, and symptoms of shock. Findings include fever, hypotension, chest and back pain, and hemoglobinuria. unwinds DNA at the replication fork and separates NCLEX Cram UWorld 1 The subthalamic nucleus Damage to this (often due to lacunar stroke) may result in contralateral hemiballism, characterized by wild, involuntary, large-amplitude, flinging movements of the proximal limbs on one side of the body. Congenital hydrocephalus presents with macrocephaly and poor feeding. Imaging shows enlarged ventricles. Untreated hydrocephalus leads to spasticity (muscle hypertonicity) due to stretching of periventricular pyramidal tracts, developmental delays, and seizures. DKA potassium levels Most patients have normal or increased serum potassium levels despite a total body potassium deficit. Replacement of potassium is a crucial step in management. Clavicle fracture the most commonly fractured bone. The sternocleidomastoid muscle causes superior displacement of the medial fragment. The weight of the arm and the pec major causes inferior displacement of the lateral fragment. Diabetes Insipidus caused by inadequate secretion (central) or renal action (nephrogenic) of ADH. Administration of exogenous ADH distinguishes the two. Damage to the hypothalamic nuclei would result in permanent central DI whereas damage to posterior pituitary would only be transient. Meniere disease characterized by tinnitus, vertigo, and sensorineural hearing loss. Its pathogenesis is related to increased volume and pressure of endolymph in the vestibular apparatus Delirium a reversible, acute-onset (compared to dementia being more gradual) confusional state characterized by fluctuating levels of consciousness with deficits in attention, memory, and executive function. Dementia does not involve fluctuations in consciousness. Listeriosis (listeria meningitis) usually transmitted through food ingestions and can cause meningitis in immunocompromised hosts (transplants/HIV). Listeria is gram-positive with tumbling motility. It grows well in cold temperatures and can therefore contaminate refrigerated food (like unpasteurized cheese) Eosinophils increased in atopic asthma and contain major basic protein which when released to kill helminths. It also may contribute to bronchial epithelial damage in patients with atopic asthma. N-acetylglutamate is an essential activator carbamoyl phosphate synthase I and is formed by the enzyme N- acetylglutamate synthetase. Hemoglobin A2 is elevated in beta-thalassemia as beta-globin chain underproduction leads to decreased hemoglobin A levels. Bilateral renal artery stenosis and ACE inhibitors or ARBs Patients with bilateral RAS may have acute renal failure if GFR falls due to the blocking of angiotensin II which constricts the efferent arterioles, thus leading to dilatation and a reduced pressure in the kidneys. Imperforate anus (dimple anus) a result of abnormal development of anorectal structures. It manifest during first couple days of life as inability to pass meconium, or it discharges form the urethra or vagina. Patients often have other malformations, most often urogenital tract Sensitivity and specificity Sensitivity = (TP/TP +FN) Specificity = (TN/TN +FP) Indepedenent events in stats If events are independent, the probability that all events will turn out the same is the product of the separate probabilities of each event. Classic galactosemia An autosomal recessive disease where patients are homozygous for a defective galactose-1-phosphate uridyltransferase gene Congestive heart failure when due to dilated cardiomyopathy or chronic ischemic disease is characterized by dilatation of 1 or both ventricles and contractile (systolic) dysfunction. Severe Vitamine E deficiency closely resembles the clinical presentation of Friedreich ataxia (ataxia, dysarthria, and loss of both position and vibration sense) due to damage of the spinocerebellar tracts, dorsal column of the spinal cord, and peripheral nerves. Polycythemia Vera a myeloproliferative disorder characterized by uncontrolled erythrocyte production. Virtually all patients with polycythemia have a mutation in JAK2, a cytoplasmic tyrosine kinase associated with EPO receptor. Acute hepatitis due to most hepatotropic viruses which cause hepatocyte ballooning degeneration and apoptosis Renal Blood Flow refers to the volume of flood that flows through the kidney per unit time and can be calculated by dividing the renal plasma flow by (1- hematocrit) RPF = (urine PAH x urine flow rate)/plasma flow rate RBF = that/1-hematocrit Hypertrophic cardiomyopathy most common cause of V-fib in individuals younger than 30 and is the most common cause of sudden cardiac death in a young athlete. A characteristic massive cardiac hypertrophy is seen. Germ Layers All adults cells can be traced back to the ectoderm, mesoderm, and endoderm. The ectoderm gives rise to the surface ectoderm (Rathke's pouch (anterior pituitary), lens and cornea, inner ear sensory organs, olfactory epithelium, nasal and oral epithelial linings, epidermis, salivary, sweat and mammary glands) the neural tube (brain and spinal cord, posterior pituitary, pineal gland, retina), and the neural crest (autonomic, sensory and celiac ganglia; schwann cells; pia and arachnoid mater; endocardial cushions; branchial arches; skull bones; melanocytes; adrenal medulla) The major stimulator of respiration PaCO2 is the major stimulator in healthy people. Even a slight increase leads to increased pulmonary ventilation, mainly through central chemoreceptors of the medulla. In COPD, response to PaCO2 is blunted and hypoxemia becomes important with peripheral chemoreceptors (carotid and aortic bodies) sensing PaO2 levels to alter breathing. Reliability the same as precision Campylobacter jejuni can lead to Guillain-Barre syndrome. Splitting defense mechanism that involves experiencing the self or others as all good or all bad. It is commonly seen in borderline personality disorder. ACTH NCLEX Cram UWorld 1 the major trophic hormone of the zona fasciculata and reticularis. Prolonged ACTH stimulation causes hyperplasia (not hypertrophy) of the zona fasiculata Primarily expressed on muscle cells and adipocytes. In contrast to the other 4 glucose transporters, it is the major transporter that is responsive to insulin (unregulated with higher insulin levels) Glut 4 characterized by a pattern of inattention and/or hyperactivity/impulsivity that interferes with ADHD functioning in 2 settings for at least 6 months before the age of 12. More common in boys than girls. a branch of the maxillary artery, which enters the sull at the foramen spinosum and courses The middle meningeal artery intracranially deep to the pterion. Skull fractures at this site can cause laceration of the middle meningeal artery and lead to an epidural hematoma. use to compare the exposure of people with the disease (cases) to the exposure of people without the disease (controls). The main measure of association is the exposure odds ratio. (odds of Case-control study exposure of people with disease/odds of exposure of people without disease) ex. healthy patients (control) and diseased patients (cases) are asked about acetaminophen use. NCLEX Cram UWorld 1 Intellectual disability, gait or postural instability, eczema, and a musty body odor in a toddler are Phenylketonuria (PKU) signs. An autosomal recessive disease. Results as a result of mutation for phenylalanine hydroxylase so levels build up. 3 types of organ rejection: hyper-acute, acute, and chronic. Acute rejection occurs within weeks of transplantation and is driven by host T cells that act Organ Rejection against donor MHC antigens. Causes a mononuclear infiltrate on histology. Prevention is with calcineurin inhibitors (tacrolimus and cyclosporine) and systemic corticosteroids. Procainamide and hydralazine have the highest risk Drug-induced Lupus of causing this, which is characterized by the Erythematosus development of lupus like symptoms with an positive ANA. Unlike SLE, anti-dsDNA is likely negative. is freely filtered from the blood in the glomerular capillaries to the tubular fluid in Bowman's space. It Paraaminohippuric acid (PAH) is also secreted from the blood into the tubular fluid by carrier proteins, which can be saturated at high blood levels of PAH found in newborns and hibernating issues and Brown adipose tissue functions to produce heat through the uncoupling of oxidative phosphorylation. It contains many more mitochondria then white adipose tissue. The major virulence factor of streptococcus pyogenes. It inhibits phagocytosis and complement Protein M activation, mediates bacterial adherence, and is the target of type-specific humoral immunity to this bacteria. a double layer of peritoneum that extends from the Lesser omentum liver to the lesser curvature of the stomach and the beginning of the duodenum. its pathogenesis begins with increased permeability of the glomerular capillary wall to plasma proteins, and thus decreased plasma oncotic pressure of the Nephrotic syndrome blood, fluid shift into the interstitium, increased aldosterone synthesis and ADH, with resultant sodium and water retention (exacerbating the edema), hyperlipidemia (to counter for losing protein), and eventually lipiuria. most occur over the lesser curvature of the stomach, at the border between acid-secreting and Gastric ulcers gastrin-secreting mucosa. The left and right gastric arteries run along the lesser curvature and are likely to be penetrated by ulcers causing gastric bleeding. usually these patients develop urge incontinence due to a loss of system inhibition on detrusor Incontinence and MS contraction in the bladder. As disease progresses, the bladder can become atonic and dilated, leading to overflow incontinence. Is associated with oxalate kidney stones. Impaired bile acid absorption in the terminal ileum leads to loss of bile acids in the feces with subsequent fat Crohn disease and oxalate malabsorption. The lipids then bind calcium ions, kidney stones which are excreted, thus free oxalate is absorbed and forms urinary calculi. will grow as "serpentine" cords on enriched media secondary to the presence of cord factor, a Mycobacteria tuberculosis mycoside. Cord factor establishes virulence through neutrophil inhibition, mitochondrial destruction, and the induced release of TNF. Most commonly results from chronic smoking, but can also occur in those with alpha-1 antitrypsin Emphysema deficiency. Patients have a decreased FEV1/FVC ratio, increased TLV, and decreased diffusion capacity Acute-onset, mid-chest pleuritic pain that Acute pericarditis decreases on sitting up and leaning forward with a pericardial friction rub is classic. can be seen in infection with mycoplasma pneumoniae. Other illnesses that result in cold Cold Agglutinins agglutinin (antibody) formation are EBV and hematologic malignancy. Cold agglutinins are specific for red blood cells that cause clumping in cold temperatures. presents soon after birth with hypotonia, poor Congenital Hypothryoidism feeding, jaundice, macroglossia, constipation and umbilical hernia. Will progress to mental retardation if not corrected Immature T lymphocytes Express both CD4 and CD8 cell surface antigens. vitamin B 12 deficiency mediated by autoimmune Pernicious Anemia destruction of parietal cells in the upper (superfical) glandular layer of the stomach. IF can't be released then. contains gamma-globin instead of beta-globin. Patients with Beta thalasemmia are asymptomatic at HbF birth due to the presence of gamma globins and HbF. Switching to HbA production and the cessation of gamma globin precipitates the symptoms of beta thalasemmia Acts as a CO2 carrier on the surface of carboxylase Biotin enzymes like in the conversion of pyruvate to oxaloacetate. Avidin in eggs avidly binds biotin. refers to the loss of free water greater than Hyperosmotic Volume electrolytes which can be seen in diabetes insipidus Contraction and in states of excessive sweating without fluid replacement. often seen due to lethal tissue ischemia. Think MI as Coagulative necrosis being prototypical. The exception is ischemic celld eath in the CNS which causes liquefactive necrosis. may lead to erythrocytosis (reason why men have Androgenic steroid abuse higher hematocrit), testicular atrophy, acne, and virilization in women (clitoromegaly, hirsutism) aka Pick's disease. Is associated with pronounced atrophy of the frontal lobe. It manifests initially with changes in personality, social behavior, and language that progress over time to a more global Frontotemporal dementia dementia with obvious neurocongnititve deficits. a cause of secondary hypertension in two to five Unilateral artery stenosis percent of hypertensive patients. the kidney affected by stenosis may become atrophied due to oxygen and nutrient deprivation. Seen bilaterally on heart valves in lupus. Just think that young women (lupus) go shopping at libman- sacks. Libman-Sacks Endocarditis Syphillis misdiagnosis Can occur with SLE because they are VLDR/RRP positive Pott's disease TB reactivation affecting the spinal column (multible vertebrae) bilateral renal aplasia, oligohydramnios, characteristic faces, and pulmonary hypoplasia. Potter Syndrome Respiratory failure is usual cause of death just after birth. Binding of autoantibodies to self antigens leads to SLE deposition of immune complexes in tissues and decrease in complement on laboratory findings. a cofactro used by hydroxylase enzymes invovled in teh synthesis of tyrosine (from phenylalanine), dopamine, and serotonin. PKU can result form BH4 deficiency due to dihydropteridine reductase deficiency. THis would result in intellectual disability Tetrahydrobiopterin (BH4) at a young age with decreased serotonin and hyperphenylalanemia. on blood smear, atypical lymphocytes can be seen Infectious mono which are CD8+ cytotoxic T cells attempting to destroy virally infected B cells. The duration and extent of UC isimportnat in determining risk. Unlike sporadic colorectal Ulcerative colitis and increased carcinomas, colitis-assoicated carcinomas are more risk for colorectal cancer likely to arise from non-polypoid dysplastic lesions, be multifocal in nature, develop early p53 mutations and late APC gene mutations, and be of higher histologic grade. characterized by a pattern of unstable relationships, mood lability, and impulsivity (like binge drinking Borderline Personality Disorder and unsafe sex) May exhibit suicidal ideation or behavior in the context of interpersonal crisis in which they feel rejected or abandoned. A result is significant if the 95% CI does not cross Statistical Signfigifigance the null value, which corresponds to a p-value 0.05. Used in cohort studies to determine how strongly a risk factor is associated with an outcome. Relative Risk (RR) Risk of outcome in exposed/risk of outcome in unexposed. 1 is the null. characterized by triad of fibrous dysplasia of the bone, endocrine abnormalities (such as early puberty or hyperthyroidism) and cafe-au lait spots. Condition results from an activating mutation in the McCune-Albright Syndrome G protein/CAMP/adenylate cyclase signaling pathway. Coast of Maine border with the cafe-au-lait (irregular border) Insulin suppresses glucagon release. a blowing, holosytrolic murmur (listen to the sound) Mitral Regurg heard best over the apex of the heart. Rheumatic heart disease is very common cause of this (bilateral knee swelling is another symptom earlier in life) Cleavage of pro-insulin in the islet cell secretory Pro-insulin granules yields insulin and C-peptide, which are stored int eh granule until they are secreted. Is acute hemorrhage into the pituitary gland usually associated with a preexisting adenoma. Presents with severe headache, cranial nerve involvement (bitemporalhemianopsia, ophthalmoplegia), and sings of meningeal irritation. Patients often have chronic symptoms before associated with the underlying tumor (decreased libido, headaches). Pituitary apoplexy Cardiovascular collapse can occur quickly to to adrenocorticla deficiency (must treat with glucocorticoids fast) receives input from the spinothalamic tract and Ventral posterior lateral dorsal columns. damage to this nucleus along with nucleus of the thalamus the ventral posterior medial nucleus can result in complete contralateral sensory loss. Receives input from the trigeminal pathway. Ventral posterior medial Damage to this nucleus along with the ventral nucleus of the thalamus posterior lateral nucleus can lead to a complete contralateral sensory loss. are the result of small vessel occulsion (by Lacunar infarctions lipohyalinosis and microatheroma) in the penetrating vessels suppling deep brain structures. along with microatheromas believed to be the primary cause of lacunar infarcts. It occurs secondary to leakage of plasma proteins through damaged endothelium (diabetes and hypertension) Lipohyalinosis and is characterized by hyaline thickening of the vascular wall, collagenous sclerosis, and accumulation of mural foamy macrophages. Liquefactive necrosis results with fluid filled cavities in a lacunar infarct. these include P. vera, ET, and primary myelofibrosis. Chronic Myeloproliferative They often has a mutation in the cytoplasmic Disorders tyrosine kinase Jak2. This leads to constant activity and activation of STAT transcription factors. the first peak - the a wave, is generated by atrial contraction. This is absent in patients with a-fib. Jugular Venous pressure tracing Calcification and thickening of the pericardium 4 Constrictive Pericarditis mm are common features on CT. Symptoms may include progressive dyspnea, peripheral edema, and ascites characterized by low plasma sodium and osmolarity, inappropriately concentrated urine (pissing out the sodium), and clinically normal body fluid volume (because ANP is released with the increased volume). An importnat cause is a SIADH paraneoplastic effect secondary to small cell carcinoma of the lung. Lung cancer with hyponatremia would be suggestive. a tetrad of cough, coryza (runny nose), conjuctivitis, Measles (rubeloa) and Koplik spots is diagnostic of this disease. Koplik spots are white or blue-gray lesions on the buccal mucosa that precede the maculopapular skin rash. develops following aspiration and can be confused with lung abscess, malignacy, or TB. Microscopic findings include filamnetous, branching, gram- Pulmonary actinomycosis positive bacteria and sulfur granules. Actinomycosis can be associated with dental caries or jaw trauma. Vulnerable to injury where it courses around the neck of the the fibula (beware fracture). Injury would The common peroneal/fibular cause weakness of dorsiflexion (deep peroneal nerve nerve) and eversion (superficial peroneal nerve) of the foot as well as loss of sensation over the dorsum of the foot. individual may develop a monolike illness that is monospot negative. Only in the immuncompromised would CMV cause retinitis, pneumonia, esophagitis, colitis, or hepatitis CMV results from cytoskeleton abnormalities, most commonly from spectrin and anykyrin. Hemolytic anemia, jaundice, and splenomegaly are classic manifestations. Hereditary Sperocytosis Sperocyrtes on blood smear. the rate-limiting enzyme in the pentose phosphate Glucose-6-phosphate pathway, the major source of NADPH, which is dehydrogenase necessary to reduce glutathione but also the biosynthesis of cholesterol, fatty acids, and steroids. Turners (XO) characterized by lymphedema, and posssible coarcation or the aorta and horseshoe kidney. Costochondritis on the DDX for CP. It is reproducible with palpation adn worsened with changes in position. preoccupation with a perceived defect in appearance and repetitive behaviors in response to preoccupation. Body Dysmorphic Disorder refers to an exaggerated drop ( 10 mmHg) in SBP during inspiration. It is usually seen in tamponade. Pulsus Paradoxus consists of two immunoglubulin monomers. It is abudant in tears, saliva, mucus, and colostrum. Provides passive immunity to the infant in colostrum. Secretory form of IgA occurs as a result of mutations in each of the two Rb genes (two hits). These patients have increased risk of other cancers, especially, osterosarcomas. Familial Retinoblastoma a reversible change in epithelial cells. That's the key. Epithelial malignancies progress from low-grade Dyplasia dypsplasia, to high grade dysplasia/carcinoma in situ to invasive carcinoma. Once its invasive, no longer reversible. Streptococcus gallylyticus causes a subacute endocarditis and bacteremia at (formerly S. Bovis) times and when it does, it is associated with colon cancer in 25% of cases (so look for it) Ether and other organic dissolve the lipid bilayer that makes up the outer solvents viral envelope. Loss of infectivity after exposure is characteristic of enveloped viruses. Hypo- or hyper-pigmented patches that become more visible after tanning with no other symptoms are characteristic of Malassezai furfur. KOH prep reveals a spaghetti and meatballs appearance. Fungi are only in the stratum corneum and more Malassezia furfur common in hot and humid places. Tend to be on the chest and back. caused by the virus HHV-6 (Rosixola). Febrile seizures can be caused by this, high grade-fever. Think a high-grade fever for 3-5 days followed by Roseola infantum an erythematous macupapular rash on the trunk. characterized by fever, pharyngitis, sand-paper like rash that spares the face, and a strawberry tongue. It is caused by Group A strep and can lead to RF or Glomerulonephritis if not treated. Scarlet Fever caused by candida infection and can be associated Oral Thrush with dentures, diabetes, and especially immunosupression. Unexplained oral thrush in otherwise healthy person suggests HIV. can be prevented by hygienic delivery and umbilical cord care and also the universal vaccination of women who are pregnant or may become pregnant as they can pass on passive immunity through IgG. Neonatal Tetanus Infants get active immunization around 2 months. A normal inhabitant of the GI tract (especially the oral cavity) . It commonly contaminates sputum cultures and its presence does not necessarily mean disease. On sputum cultures it would appear as Candida albicans "germ tubes" at 37 degrees C. characterized by ulcerative lesions with intranuclear inclusions. It is usually seen in children who are experiencing primary infection with HSV1, a double stranded, enveloped DNA virus. Gingivostomatitis causes pulmonary, CNS, and/or skin disease in the immunocompromised (the cane). Pulmonary nocariosis can present as cavitary pneumonia often confused with TB. Sputum stain would reveal gram- Nocardia positive branching organisms. Genetic variations created during this viruses replications result in marked variety in the antigenic Hep C structure of HCV envelop proteins, thus explaining NCLEX Cram UWorld 1 Often done first through a screening (RPR or VDRL) Treponema Pallidum Dx and then a confirmatory test looking for specific antibodies against the bacteria. endemic in states surrounding Mississippi and Ohio River Valleys (kind of like histo). Can cause pulmonary disease in the immunocompetent hose while dissemination would typically occur in the immunocompromised individual (skin and bones). Blastomyces dermatitidis Respiratory fluids would show round yeast with thick walls and broad-based budding. EBV binds CD21 on host B cells to enter the cell. EBV Patients with sickle cell disease may have functional asplenia due to multiple infarcts thus predisposing Sickle Cell Disease to infection with encapsulated organisms like Salmonella, a common cause of osteomyelitis in patients with SCD. It has a special capsule that resists opsonization. NCLEX Cram UWorld 1 infection is characterized by acute, self-limited, febrile pharyngitis, cough, nasal congestion, and enlarged cervical lymph nodes. It usually occurs among individuals close together- camps or military barracks. Adenovirus The virus that causes croup. It is seen after a recent history of URI where there is a brassy, barking cough afterwards with dyspnea and stridor Otherwise known as viral lanrygotracheitis and is seen in children. A member of the paramyxovirus Parainfluenza virus family . causes late-onset (spores germinated and produce toxin in the GI tract unlike Staph or Bacillus food Clostridium Pefringens poisoning which are early and preformed) food poisoning and clostridial myonecrosis (gas gangrene). The food poisoning is toxin-mediated and causes a transient wattery diarrhea. Identifies organisms that have mycolic acid in their walls, namely the mycobacterium and more weakly Acid-fast stain Nocardia species. It is done by applying NCLEX Cram UWorld 1 causes diphtheria, an acute bacterial disease that initially infects the oropharynx. It causes disease via its A/B exotoxin. The B binding allows penetration of A into the cell to inhibit ribosome function. Neural and cardiac toxicity can occur if it become systemic. Immunization with DPT (the toxoid itself) induces Corynebacterium diptheriae production of IgG against the exotoxin B subunit so no binding can occur. leads to formation of necrotic skin wound with an erythematous and edematous border. It is most commonly acquired occupationaly in those who handle livestock or due to biological weapon (but Cutaneous Antrax this is pulmonary with nearly 100% mortality) virulence factor of S. Aureus (Gram positive clusters Protein A on GS) that binds Fc portion of IgG and prevents complement activation, opsonization, and phagocytosis Intrabdominal infection from Often polymicrobial but include Bacteroides fragilis ruptured appendix and E.coli. NCLEX Cram UWorld 1 Necrotizing Fasciitis a severe infection of the subcutaenous tissue that is a surgical emergency. Often polymicrobial, but Strept pyogenes has been indicated with is PYR positive, beta hemolytic, and Gram-possitive cocci that grows in chains. S. Aureus and Clostridium perfringens would also be possible causes. Klebsiella an encapsulated, lactose-fermenting, gram - negative bacillus that appears mucoid in culture. It causes pneumonia in subjects with impaired immune defenses, especially alcoholics. Characterized by production of the currant jelly sputum. Schistosomiasis Humans acquire this via contact with freshwater soures that contain infected snails schistosoma larvae. S japonicum and Smansoni cause intestinal and hepatic schistosomiasis, while S haematobium causes urinary schistosomiasis. Clinical symptoms result from a TH2 response to the eggs in the body- marked fibrosis and ulceration and scarring of the bowel or bladder wall/ureters depending on the species. NCLEX Cram UWorld 1 The spleen acts as both a blood filter capable of removing circulating pathogens and as a major site of opsonizing antibody synthesis. Loss of spleen increases risk for infection causes by encapsulated organisms. Especially the SHiNs. A single-stranded postive- sense RNA virus like rhinovirus could be infectious without any other parts since all it needs is host machinery and then boom. Diagnosis of Genital herpes PCR, direct folourescnece antibody screening or Tzanck smear. Scabies A highly contagious disease that presents with an intensely pruritic rash (usually worse at night) in the flexor surfaces of the wrist, lateral surfaces of the fingers, and finger webs. usually have small, crusted, red papules scattered around. Dx is made by seeing the mites on light microscopy. Babesiosis should be considered in patients with febrile illness who reside in geographic areas where they are exposed to the Ixodes tick (northeastern United States). Blood smear would show intraerythrocytic organisms. Neisseria Meningititidis can cause an upper respiratory tract infection, meningitis, and meningococemia (rash too). Immunity against these bacteria are provded by antibodies against the polysaccharide capsule. Common in college dorms. Parvoviridae THE ONLY viral family where members are both non-enveloped and single-stranded. This includes Parvovirus B19 which causes erythema infectiosum (fifth disease), aplastic crises in sickle cell anemia, and hydrops fetalis (Torch) HSV2 classically infects the sacral sensory ganglia (dorsal) to cause a reccurent, painful genital rash Cryptococcus neoformans causes meningoencephalitis in HIV + patients. The latex agglutination test detects the polysaccharide capsule of Cryptococcus. India ink staining shows oval budding yeast. Strongyloides stercoralis infection begins following skin penetration by filarifrom (infectious) larva and is diagnosed by finding rhabditiform (noninfectious) larvae in the stool. V. cholerae usually requires a massive infectious dose to cause disease because sensitive to gastric acidity. However, in patients taking omeprazole or any other condition that reduces acidity, the minimum infectious dose is lowered significantly. Clostridium tentani its toxin causes all the symptoms, which travels from the wound up the motor axons to the spinal cord where it causes inhibibition of inhibitory interneurons (GABA down) and unregulated firign of primary motor neurons so you get tismus ( jaw stiffness) and risus sardonicus. Shigella A very low infectious dose is needed to cause infection. H. flu requires X (hematin) and V (NAD+). It can grow on sheep agar only in the presence of S. Aureus because it produces the needed X and V factors. Toxoplasmosis In patients with HIV, the presence of multiple ring- enhancing lesions with mass effect (seizures) is often indicative of toxoplasmosis. First-line treatment would be pyrimethamine and Sulfadiazine. If the patient doesn't get better, suspect a primary central nervous system lymphoma where abnormal b lymphocytes would be seen. Mycoplasma pneumonaie The causative agent of walking pneumonia. Hit has no peptidoglycan cell wall and shares antigens with human erythrocytes. When the body mounts an immune response to the antigen, it also lyses RBCs leading to anemia. The antibodies causing this RBC destruction are called cold agglutinins C. diff has toxins A and B which exert their effect by disrupting the actin cytoskeletal structure of enterocytes. Toxin A is more inflammatory and fluid secretion while toxin B is more cytotoxic. Common antibiotics that can lead to C. diff overgrowth are clinamycin, fluroquinolones, penicillins, and broad spectrum cephalosporins. Hepatitis E an unenveloped, single-stranded RNA virus spread through the fecal oral-route especially in Asia, Africa, and Mexico. It does have high morality in infected pregnant woman from fulminant hepatitis. Shiga-like toxins (aka Vero cytotoxins) produced by Enterohemorrhagic E.Coli (EHEC). Nearly identical to the Shiga toxin produced by Shigella dysenteriae. The toxin is an A-B toxin that inhibits the 60s ribosomal subunit in human cells thereby blocking protein synthesis by preventing the binding of tRNA (adenine replaced). Unlike, diptheria toxin andexotoxin A or Pseudomonas, this toxin does not act on EF2. Hepatitis B Replication of hepatitis B genome occurs within a newly synthesized capsid through the action of reverse transcriptase on an RNA template. The mature capsid contain partially double-stranded circular DNA and reverse transcriptase. Nontypable strains of H. flu the strains that do not form an antiphagocytic capsule and are part of the noraml upper respiratory flora but can cause otitis media, sinusitis, and bronchitis. Immunity is not conferred then by the type B capsular strain vaccine. Aspergillus fumigatus causes opportunistic infections in immunosuppressed and neutropenic patients (invasive aspergillosis). Aspergillosis can also be colonizing of old cavities like TB (aspergilloma) and allergic (Allergic bronchopulmonary aspergillosis) Confounding Bias occurs when the exposure-disease relationship is muddied by the effect of an extraneous factor that has correlations with both the exposure and the disease. Confounding bias can result in the false association of an exposure with a disease. Ecological Study The unit of analysis in ecological studies is populations not individuals Cross-sectional study (aka a prevalence study) exposure and outcome (prevalence) are measured simultaneously at a particular point in time (snap- shot study). In other study designs, a certain time period separates the exposure from the outcome. Recall bias results from inaccurate recall of past exposure by people in the study and applies mostly to retrospective studies like case-control studies. People who have suffered an adverse event are more likely to recall risk factors than those who did not. Absolute risk reduction Event rate in control group- event rate in treatment group A meta-analysis groups results of several trials to increase statistical power and provide an overall pooled effect estimate. Matching Used in case-controlled studies to control confounding. Matching variables should always be the potential confounders of the study such as age, race, smoking. Risk The probability of developing a disease over a certain period of time. Its just the number of affected individuals by the total number of subjects in the corresponding exposure group. Relative risk on the other hand is dividing each risk by each risk. Specificity NCLEX Cram UWorld 1 The number of true negatives divided by the total number of subjects actually without the disease. False positives = (1- specificity)* number of patients actually without the disease. It is the ability to correctly identify individuals without the disease. Specificity should be high in Confidentiality It is unethical to discuss ANY information regarding diagnosis, treatment, prognosis, etc. with a physician who is not involved in the patient's care. Likewise, the physician should neither confirm nor deny whether the person of interest is, in fact, a patient. Child abuse Once child abuse is suspected, immediately contact CPS (do not ask the parents as this can be dangerous and they may flee with child) Incident vs. prevalent cases Incident cases represent new cases diagnosed in a given time period. Prevalent cases are the total number of cases (both new and old) at a particular point in time. Any treatment that prolong survival but does not cure the disease will increase the prevalence due to an increase in the number of afflicted (but still living) individuals over time. The Hawthorne/observer effect The tendency of study subjects to change their behavior as a result of their awareness that they are being studied Berkson's bias refers to selection bias created by choosing hospitalized patients as the control group Lead-time bias refers to the apparent prolongation of survival after applying a screening test that detects a disease earlier than it would have otherwise been detected without any real effect on prognosis Pygmalion effect describes the fact that a researcher's belief in the efficacy of treatment can potentially affect the outcome. Treating friends Providing informal treatment to friends is ethically problematic and should generally be limited to emergency situations in which no other physician is available. Odd's ratio a measure of association between an exposure and an outcome axd/bxc from table. Attrition bias a form of selection bias where there is disproportionate loss to follow-up between the exposed and unexposed group in prospective studies (may give inaccurate results) The power of a study can be increased as the sample size increases (why often a single study may not be significant but then the meta-anaylsis is). Therefore, the large the sample, the greater the ability of a study to detect a difference when one truly exists (aka you decrease type II error- saying no association when there is) Increasing prevalence and stable incidence Think of factors that prolong the duration of a disease Naming patients Physicians should as