CLINICAL BIOCHEMISTRY NOTES
1. Clinical significance of biochemical tests- the concept of health and disease, factors
causing diseases, the clinical significance of biochemical tests and their role in
diagnosis, monitoring, and therapy of disease
Health
According to the World Health Organization, Health is defined as the state of complete physical,
mental, and social well-being and not merely the absence of disease
Disease
Any harmful deviation from the normal structural or functional state of an organism, generally
associated with certain signs and symptoms and differing in nature from physical injury
Types of diseases
Factors causing disease
Invasion by pathogen
Lack of nutrition
Genetic disorder
Other personal behavioral habits like tobacco, alcohol, physical activity
Environment
Aging
Disturbances in human biochemistry - electrolyte and hormonal imbalances, defective nutrient
ingestion or absorption.
Biochemical approaches are often fundamental in illuminating the causes of diseases and in
designing appropriate therapies.
,Biochemical laboratory tests represent an integral component of diagnosis and monitoring of
treatment.
Medical diagnosis is the process of determining which disease or condition explains a person's
symptoms and signs.
Tests
Hormone levels
Thyroid- T3,T4, TSH
Insulin
Follicle stimulating hormone, GH etc
Toxicity
Heavy metal blood test
Alcohol
Other toxins
Deficiency
Iron
B12
D3
Ca etc
Infection
Malaria
Dengue
Tuberculosis
Typhoid
Monitoring
Blood glucose level
Platelet count
Fertility Cycle Monitoring
Maternal Serum Screening
Treatment of Immunological-Based Disorders
markers of inflammation, such as C-reactive protein (CRP) and Erythrocyte Sedimentation Rate
(ESR), can indicate the presence of inflammatory diseases like arthritis
Treatment of Cancer
tumor markers, such as prostate-specific antigen (PSA) and CA-125, can indicate the presence
of cancer
Biomarker Discovery for Disease Treatment-
,Biomarkers are substances found in the body that can indicate the presence of a particular
disease or condition.
2. Specimen collection and processing- a collection of blood vein puncture, collection
with a syringe, collection with an evacuated tube, skin puncture, arterial puncture,
anticoagulants, plasma, and serum. Collection of urine:-Timed urine specimens, and
urine preservatives.
Specimen- A sample of tissue, blood, urine, etc, taken for diagnostic examination or evaluation
Blood: Fluid connective tissue, contains solid and liquid components.
Formed in bone marrow by a tightly regulated system called hematopoiesis.
, Blood vessels are of three types: veins, artery and capillary
Venous blood-
Venous blood is deoxygenated blood that flows from tiny capillary blood vessels within the
tissues into progressively larger veins.
Venous blood is the specimen of choice for most routine laboratory tests.
The blood is obtained by direct puncture to a vein, most often located in the antecubital area of
the arm or
the back (top) of the hand.
At times, venous blood may be obtained using a vascular access device (VAD) such as a
central venous pressure line or an IV start.
Most laboratory reference ranges for blood analytes are based on venous blood.
Arterial blood-
Oxygenated blood is pumped through the left side of the heart via arteries.
The most common reason for the collection of arterial blood is the evaluation of arterial blood
gases.
- Measure of oxygen and carbon-dioxide tension as well as pH in Arterial blood gases
(ABGs)
- Critical for assessment of oxygenation problems in patients with pneumonia,
pneumonitis, and pulmonary embolism.
Arterial blood may be obtained directly from the artery (most commonly, the radial artery) by
personnel who are trained.
Arterial blood may also be obtained from a vascular access device (VAD) inserted in an artery,
such as a femoral arterial line or catheter.
Capillary blood-
Capillary blood is obtained from capillary beds that consist of the smallest veins (venules) and
arteries (arterioles) of the circulatory system.
The venules and arterioles join together in capillary beds, forming a mixture of venous and
arterial blood.
The specimen from a dermal puncture will therefore be a mixture of arterial and venous blood
along with interstitial and intracellular fluids.
1. Clinical significance of biochemical tests- the concept of health and disease, factors
causing diseases, the clinical significance of biochemical tests and their role in
diagnosis, monitoring, and therapy of disease
Health
According to the World Health Organization, Health is defined as the state of complete physical,
mental, and social well-being and not merely the absence of disease
Disease
Any harmful deviation from the normal structural or functional state of an organism, generally
associated with certain signs and symptoms and differing in nature from physical injury
Types of diseases
Factors causing disease
Invasion by pathogen
Lack of nutrition
Genetic disorder
Other personal behavioral habits like tobacco, alcohol, physical activity
Environment
Aging
Disturbances in human biochemistry - electrolyte and hormonal imbalances, defective nutrient
ingestion or absorption.
Biochemical approaches are often fundamental in illuminating the causes of diseases and in
designing appropriate therapies.
,Biochemical laboratory tests represent an integral component of diagnosis and monitoring of
treatment.
Medical diagnosis is the process of determining which disease or condition explains a person's
symptoms and signs.
Tests
Hormone levels
Thyroid- T3,T4, TSH
Insulin
Follicle stimulating hormone, GH etc
Toxicity
Heavy metal blood test
Alcohol
Other toxins
Deficiency
Iron
B12
D3
Ca etc
Infection
Malaria
Dengue
Tuberculosis
Typhoid
Monitoring
Blood glucose level
Platelet count
Fertility Cycle Monitoring
Maternal Serum Screening
Treatment of Immunological-Based Disorders
markers of inflammation, such as C-reactive protein (CRP) and Erythrocyte Sedimentation Rate
(ESR), can indicate the presence of inflammatory diseases like arthritis
Treatment of Cancer
tumor markers, such as prostate-specific antigen (PSA) and CA-125, can indicate the presence
of cancer
Biomarker Discovery for Disease Treatment-
,Biomarkers are substances found in the body that can indicate the presence of a particular
disease or condition.
2. Specimen collection and processing- a collection of blood vein puncture, collection
with a syringe, collection with an evacuated tube, skin puncture, arterial puncture,
anticoagulants, plasma, and serum. Collection of urine:-Timed urine specimens, and
urine preservatives.
Specimen- A sample of tissue, blood, urine, etc, taken for diagnostic examination or evaluation
Blood: Fluid connective tissue, contains solid and liquid components.
Formed in bone marrow by a tightly regulated system called hematopoiesis.
, Blood vessels are of three types: veins, artery and capillary
Venous blood-
Venous blood is deoxygenated blood that flows from tiny capillary blood vessels within the
tissues into progressively larger veins.
Venous blood is the specimen of choice for most routine laboratory tests.
The blood is obtained by direct puncture to a vein, most often located in the antecubital area of
the arm or
the back (top) of the hand.
At times, venous blood may be obtained using a vascular access device (VAD) such as a
central venous pressure line or an IV start.
Most laboratory reference ranges for blood analytes are based on venous blood.
Arterial blood-
Oxygenated blood is pumped through the left side of the heart via arteries.
The most common reason for the collection of arterial blood is the evaluation of arterial blood
gases.
- Measure of oxygen and carbon-dioxide tension as well as pH in Arterial blood gases
(ABGs)
- Critical for assessment of oxygenation problems in patients with pneumonia,
pneumonitis, and pulmonary embolism.
Arterial blood may be obtained directly from the artery (most commonly, the radial artery) by
personnel who are trained.
Arterial blood may also be obtained from a vascular access device (VAD) inserted in an artery,
such as a femoral arterial line or catheter.
Capillary blood-
Capillary blood is obtained from capillary beds that consist of the smallest veins (venules) and
arteries (arterioles) of the circulatory system.
The venules and arterioles join together in capillary beds, forming a mixture of venous and
arterial blood.
The specimen from a dermal puncture will therefore be a mixture of arterial and venous blood
along with interstitial and intracellular fluids.
