NBME Step 3 Form 4 Practice Exam
– Complete High-Yield Questions,
Pearls, and Answers
-all other fungal skin infections can be treated with topicals (ketoconizole, clotrimazole, econazole,
terbinafine, miconazole, sertaconazole, sulconazole, tolnaftate, naftifine)
-oral ketoconazole causes hepatotoxicity and gynecomastia
,-no topical form of fluconazole
Which oral abx does not adequately cover skin? - ANSWER -ciprofloxacin
Good choices for tx of skin infections - ANSWER --oral diclox, cephalexin, cefadroxyl
-IV nafcillin or cefazolin
-if PCN allergy, then erythromycin, azithromycin, clarithromycin, levoflox, gati or moxi (but NOT cipro)
-vanc, linezolid or bactrim for MRSA
Impetigo - ANSWER --superficial skin infection caused by staph and group A strep
-weeping, oozy, honey-colored crust
-contagious and can cause GN (but not rheumatic fever)
-tx with topical antibiotics
Erysipelas - ANSWER --deeper than impetigo, involves both dermis and epidermis; bright red, swollen,
angry appearance of face
-fever, chillls, bacteremia
-caused by group A strep
-tx with oral or IV abx (if cx positive strep, can use PCN G or ampicillin)
Folliculitis - ANSWER --tx with topical mupirocin
-think Pseudomonas if whirlpool exposure
Furuncles and carbuncles - ANSWER -drain and tx with oral diclox or cefadroxyl
Necrotizing fasciitis - ANSWER --strep and clostridium most common b/c they produce toxins
-DM is a risk factor
-very high fever, portal of entry, pain out of proportion, bullae, palpable crepitus
-elevated CPK
,-imaging shows subcu air
-pt. should go directly to surgery, no need for imaging
-tx with amp/sulbactam, pip/tazo, tic/clav
-if definite strep pyogenes, then clinda + PCN
Norwegian scabies - ANSWER --particularly nasty version of scabies seen in immunocompromised ppl
(HIV+)
-causes severe crusting
-scabies are too small to see, must look for burrows in the web spaces
-tx with permethrin or lindane (more toxicity) or oral ivermectin
Niacin deficiency - ANSWER -the 3 Ds of vitamin B3 deficiency (also called pellagra):
-dermititis
-diarrhea
-dementia
Dermatitis is usually bilaterally symmetric and is found mainly on sun-exposed areas of the body. The
changes at first comprise redness, thickening, and roughening of the skin, which may be followed by
extensive scaling and desquamation, producing fissures and chronic inflammation. Similar lesions may
occur in the mucous membranes of the mouth and vagina. Diarrhea is caused by atrophy of the
columnar epithelium of the gastrointestinal (GI) tract mucosa, followed by submucosal inflammation.
Atrophy may be followed by ulceration. Dementia results from degeneration of the neurons in the brain,
accompanied by degeneration of the corresponding tracts in the spinal cord. The spinal cord lesions
bear a close resemblance to the posterior column alterations observed in pernicious anemia.
Riboflavin deficiency - ANSWER -Riboflavin=B2
-angular stomatitis (changes at the angles of the mouth)
-cheilosis (cracked lips)
-glossitis
-ocular problems (corneal neovascularization)
-skin changes
, Thiamine deficiency - ANSWER -The major targets of thiamine (B1) deficiency are the peripheral nerves,
the heart, and the brain, so persistent thiamine deficiency gives rise to three distinctive syndromes:
• A polyneuropathy (dry beriberi)
• A cardiovascular syndrome (wet beriberi)
• Wernicke-Korsakoff syndrome
Dry beriberi: peripheral neuropathy (demyelination)
Wet beriberi: congestive cardiomyopathy with biventricular failure
Wernicke's syndrome: ataxia, confusion, nystagmus, mamillary body hemorrhage
Korsakoff's syndrome: antegrade or retrograde amnesia; demyelination in limbic system
Vitamin B6 deficiency - ANSWER -Also called pyridoxine. Clinical findings in vitamin B6-deficient patients
resemble those seen in patients with riboflavin and niacin deficiency.
-seborrheic dermatitis
-cheilosis
-glossitis
-peripheral neuropathy
-sometimes convulsions
-sideroblastic anemia (microcytic anemia with ringed sideroblasts)
Vitamin C deficiency - ANSWER --weak capillaries and venules
-gingival swelling
-loose teeth
-hemorrhages
-secondary bacterial periodontal infection
– Complete High-Yield Questions,
Pearls, and Answers
-all other fungal skin infections can be treated with topicals (ketoconizole, clotrimazole, econazole,
terbinafine, miconazole, sertaconazole, sulconazole, tolnaftate, naftifine)
-oral ketoconazole causes hepatotoxicity and gynecomastia
,-no topical form of fluconazole
Which oral abx does not adequately cover skin? - ANSWER -ciprofloxacin
Good choices for tx of skin infections - ANSWER --oral diclox, cephalexin, cefadroxyl
-IV nafcillin or cefazolin
-if PCN allergy, then erythromycin, azithromycin, clarithromycin, levoflox, gati or moxi (but NOT cipro)
-vanc, linezolid or bactrim for MRSA
Impetigo - ANSWER --superficial skin infection caused by staph and group A strep
-weeping, oozy, honey-colored crust
-contagious and can cause GN (but not rheumatic fever)
-tx with topical antibiotics
Erysipelas - ANSWER --deeper than impetigo, involves both dermis and epidermis; bright red, swollen,
angry appearance of face
-fever, chillls, bacteremia
-caused by group A strep
-tx with oral or IV abx (if cx positive strep, can use PCN G or ampicillin)
Folliculitis - ANSWER --tx with topical mupirocin
-think Pseudomonas if whirlpool exposure
Furuncles and carbuncles - ANSWER -drain and tx with oral diclox or cefadroxyl
Necrotizing fasciitis - ANSWER --strep and clostridium most common b/c they produce toxins
-DM is a risk factor
-very high fever, portal of entry, pain out of proportion, bullae, palpable crepitus
-elevated CPK
,-imaging shows subcu air
-pt. should go directly to surgery, no need for imaging
-tx with amp/sulbactam, pip/tazo, tic/clav
-if definite strep pyogenes, then clinda + PCN
Norwegian scabies - ANSWER --particularly nasty version of scabies seen in immunocompromised ppl
(HIV+)
-causes severe crusting
-scabies are too small to see, must look for burrows in the web spaces
-tx with permethrin or lindane (more toxicity) or oral ivermectin
Niacin deficiency - ANSWER -the 3 Ds of vitamin B3 deficiency (also called pellagra):
-dermititis
-diarrhea
-dementia
Dermatitis is usually bilaterally symmetric and is found mainly on sun-exposed areas of the body. The
changes at first comprise redness, thickening, and roughening of the skin, which may be followed by
extensive scaling and desquamation, producing fissures and chronic inflammation. Similar lesions may
occur in the mucous membranes of the mouth and vagina. Diarrhea is caused by atrophy of the
columnar epithelium of the gastrointestinal (GI) tract mucosa, followed by submucosal inflammation.
Atrophy may be followed by ulceration. Dementia results from degeneration of the neurons in the brain,
accompanied by degeneration of the corresponding tracts in the spinal cord. The spinal cord lesions
bear a close resemblance to the posterior column alterations observed in pernicious anemia.
Riboflavin deficiency - ANSWER -Riboflavin=B2
-angular stomatitis (changes at the angles of the mouth)
-cheilosis (cracked lips)
-glossitis
-ocular problems (corneal neovascularization)
-skin changes
, Thiamine deficiency - ANSWER -The major targets of thiamine (B1) deficiency are the peripheral nerves,
the heart, and the brain, so persistent thiamine deficiency gives rise to three distinctive syndromes:
• A polyneuropathy (dry beriberi)
• A cardiovascular syndrome (wet beriberi)
• Wernicke-Korsakoff syndrome
Dry beriberi: peripheral neuropathy (demyelination)
Wet beriberi: congestive cardiomyopathy with biventricular failure
Wernicke's syndrome: ataxia, confusion, nystagmus, mamillary body hemorrhage
Korsakoff's syndrome: antegrade or retrograde amnesia; demyelination in limbic system
Vitamin B6 deficiency - ANSWER -Also called pyridoxine. Clinical findings in vitamin B6-deficient patients
resemble those seen in patients with riboflavin and niacin deficiency.
-seborrheic dermatitis
-cheilosis
-glossitis
-peripheral neuropathy
-sometimes convulsions
-sideroblastic anemia (microcytic anemia with ringed sideroblasts)
Vitamin C deficiency - ANSWER --weak capillaries and venules
-gingival swelling
-loose teeth
-hemorrhages
-secondary bacterial periodontal infection
