Unit #6D – Clinical Unit #6D – Clinical Laboratory Testing – Laboratory Testing –

Basic Clinical Basic Clinical ChemistryChemistry

Cecile Sanders, M.Ed., Cecile Sanders, M.Ed., MT(ASCP), MT(ASCP), CLS (NCA)CLS (NCA)

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryPurpose of Clinical Chemistry TestsPurpose of Clinical Chemistry Tests

– Measure levels of substances found Measure levels of substances found normally in human blood that have normally in human blood that have biological functions. Examples: biological functions. Examples: Glucose, CalciumGlucose, Calcium

– Detect or measure non-functional Detect or measure non-functional metabolites or waste products. metabolites or waste products. Examples: Creatinine, Blood Urea Examples: Creatinine, Blood Urea Nitrogen (BUN)Nitrogen (BUN)

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Detect or measure substances that Detect or measure substances that

indicate cell damage or disease. indicate cell damage or disease. Examples: Liver enzymes, such as ALT, Examples: Liver enzymes, such as ALT, Cardiac enzymes, such as CK-MBCardiac enzymes, such as CK-MB

– Detect or measure drugs or toxic Detect or measure drugs or toxic substances. Examples: Dilantin, Drugs substances. Examples: Dilantin, Drugs of abuse screenof abuse screen

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry Types of Specimens for Chemical Types of Specimens for Chemical

AnalysisAnalysis– Whole blood, serum or plasma. The Whole blood, serum or plasma. The

most common specimen is serum, most common specimen is serum, collected in a tube with no anticoagulant collected in a tube with no anticoagulant so that the blood will clot. so that the blood will clot.

– Urine – often 24 hour collectionsUrine – often 24 hour collections– Others – Cerebrospinal Spinal Fluid Others – Cerebrospinal Spinal Fluid

(CSF) and other fluids(CSF) and other fluids

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry Collection and Handling of Blood Collection and Handling of Blood

Specimens for Chemical AnalysisSpecimens for Chemical Analysis– Blood collection tubes for obtaining Blood collection tubes for obtaining

serum - Serum Separator Tubes (SST) do serum - Serum Separator Tubes (SST) do not have an anticoagulant but do contain not have an anticoagulant but do contain a gel substance which will form an a gel substance which will form an interface between the clot and the interface between the clot and the serum when the blood specimen is serum when the blood specimen is centrifuged. These tubes are sometimes centrifuged. These tubes are sometimes referred to as “Tiger Tops”.referred to as “Tiger Tops”.

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Blood collection Blood collection

tubes for obtaining tubes for obtaining plasmaplasma

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Patient preparation; time of collection; & Patient preparation; time of collection; &

effects of eating on chemistry analysiseffects of eating on chemistry analysis

Some specimens are increased or decreased Some specimens are increased or decreased after eating (ex. Glucose, triglycerides), so it after eating (ex. Glucose, triglycerides), so it is important to know what the test and is important to know what the test and collection method call for. Specimens for collection method call for. Specimens for these tests are usually collected in a fasting these tests are usually collected in a fasting state.state.

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry Sometimes serum or Sometimes serum or

plasma appears plasma appears lipemia (milky) after lipemia (milky) after a patient has eaten a patient has eaten a fatty meal. a fatty meal. Lipemia affects most Lipemia affects most chemistry analyses. chemistry analyses. The blood must be The blood must be recollected when the recollected when the patient is fasting.patient is fasting.

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry Clinical Chemistry TestsClinical Chemistry Tests

– Normal or Reference Values – range of Normal or Reference Values – range of values for a particular chemistry test values for a particular chemistry test from healthy individualsfrom healthy individuals

– Chemistry Panel grouping – some tests Chemistry Panel grouping – some tests are “bundled” according to the system are “bundled” according to the system or organ targeted. Examples: thyroid or organ targeted. Examples: thyroid panel, liver panel, cardiac panel, kidney panel, liver panel, cardiac panel, kidney panel, basic metabolic panel, etc.panel, basic metabolic panel, etc.

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry Commonly Performed Chemistry Commonly Performed Chemistry

Tests or AnalytesTests or Analytes– Proteins – essential components of cells Proteins – essential components of cells

and body fluids. Some made by body, and body fluids. Some made by body, others acquired from diet. Provides others acquired from diet. Provides information about state of hydration, information about state of hydration, nutrition and liver function, since most nutrition and liver function, since most serum proteins are made in the liver.serum proteins are made in the liver.

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Electrolytes – sometimes called “lytes”Electrolytes – sometimes called “lytes” Includes sodium (Na), potassium (K), Includes sodium (Na), potassium (K),

chloride (Cl) and bicarbonate (HCOchloride (Cl) and bicarbonate (HCO3-3-))Collectively these have a great effect on Collectively these have a great effect on

hydration, acid-base balance and osmotic hydration, acid-base balance and osmotic pressure as well as pH and heart and muscle pressure as well as pH and heart and muscle contractioncontraction

Levels differ depending on if inside vs. Levels differ depending on if inside vs. outside cellsoutside cells

Important in transport of substances into Important in transport of substances into and out of cellsand out of cells

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– MineralsMinerals

CalciumCalcium– Used in coagulation and muscle contractionUsed in coagulation and muscle contraction– 99% is in skeleton and is not metabolically active99% is in skeleton and is not metabolically active– Influenced by vitamin D, parathyroid hormone, Influenced by vitamin D, parathyroid hormone,

estrogen and calcitoninestrogen and calcitonin– Hypercalcemia – occurs in parathyroidism, bone Hypercalcemia – occurs in parathyroidism, bone

malignancies, hormone disorders, excessive malignancies, hormone disorders, excessive vitamin D, and acidosis; may cause kidney stonesvitamin D, and acidosis; may cause kidney stones

– Hypocalcemia – can cause tetany; occurs in Hypocalcemia – can cause tetany; occurs in hypoparathyroidism, vitamin D deficiency, poor hypoparathyroidism, vitamin D deficiency, poor dietary absorption and kidney diseasedietary absorption and kidney disease

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryPhosphorusPhosphorus

– 80% in bone and rest in energy compounds such 80% in bone and rest in energy compounds such as ATPas ATP

– Influenced by calcium and certain hormonesInfluenced by calcium and certain hormones IronIron

– Essential for hemoglobinEssential for hemoglobin– Deficiency results in anemia; may be caused by Deficiency results in anemia; may be caused by

lack of iron in diet, poor absorption, poor release lack of iron in diet, poor absorption, poor release of stored iron or loss due to bleedingof stored iron or loss due to bleeding

– Increased in hemolytic anemia, increased iron Increased in hemolytic anemia, increased iron intake or blocked synthesis of iron-containing intake or blocked synthesis of iron-containing compounds, such as in lead poisoningcompounds, such as in lead poisoning

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Kidney Function TestsKidney Function Tests

Serum CreatinineSerum Creatinine– Best test for overall kidney function; not affected Best test for overall kidney function; not affected

by diet or hormone levelsby diet or hormone levels– Waste product of muscle metabolismWaste product of muscle metabolism– Serum creatinine rises when kidney function is Serum creatinine rises when kidney function is

impairedimpaired

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryBUN (Blood Urea Nitrogen)BUN (Blood Urea Nitrogen)

– BUN is surplus amino acids that are converted to BUN is surplus amino acids that are converted to urea and excreted by kidneys as a waste producturea and excreted by kidneys as a waste product

– BUN influenced by diet and hormones, so it is BUN influenced by diet and hormones, so it is NOT as good an indicator of renal function as NOT as good an indicator of renal function as serum creatinine levelsserum creatinine levels

– BUN increased in kidney disease, high protein BUN increased in kidney disease, high protein diet, and after administration of steroidsdiet, and after administration of steroids

– BUN decreased in starvation, pregnancy and in BUN decreased in starvation, pregnancy and in persons on a low protein dietpersons on a low protein diet

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryUric AcidUric Acid

– Formed from breakdown of nucleic acids and Formed from breakdown of nucleic acids and excreted as a waste product by kidneysexcreted as a waste product by kidneys

– Increased in kidney disease, but most often used Increased in kidney disease, but most often used to diagnosis gout (pain in joints, mainly big toe, to diagnosis gout (pain in joints, mainly big toe, due to precipitated uric acid crystals)due to precipitated uric acid crystals)

– Also increased in increased cell destruction, such Also increased in increased cell destruction, such as after massive radiation or chemotherapyas after massive radiation or chemotherapy

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Liver Function TestsLiver Function Tests

Liver functions:Liver functions:– Synthesizes glycogen from glucoseSynthesizes glycogen from glucose– Makes plasma proteins (albumin, lipoproteins, Makes plasma proteins (albumin, lipoproteins,

coagulation proteins)coagulation proteins)– Forms cholesterol and degrades it into bile acids, Forms cholesterol and degrades it into bile acids,

which emulsifies fats for absorptionwhich emulsifies fats for absorption– Stores iron, glycogen, vitamins and other Stores iron, glycogen, vitamins and other

substancessubstances– Destroys old blood cells and recycles components Destroys old blood cells and recycles components

of hemoglobinof hemoglobin

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryTotal BilirubinTotal Bilirubin

– Waste production of hemoglobin breakdownWaste production of hemoglobin breakdown– Increased in excessive RBC breakdown, such as Increased in excessive RBC breakdown, such as

hemolytic anemia, or impaired liver function or hemolytic anemia, or impaired liver function or some sort of obstruction, such as a tumor or gall some sort of obstruction, such as a tumor or gall stonestone

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryLiver Enzymes – levels increase following Liver Enzymes – levels increase following

damage to liver tissuesdamage to liver tissues– Alkaline Phosphatase (ALP or AP) - Greatly Alkaline Phosphatase (ALP or AP) - Greatly

increased in liver tumors and lesions; moderately increased in liver tumors and lesions; moderately increased in diseases such as hepatitisincreased in diseases such as hepatitis

– Alanine Aminotransferase (ALT; formerly called Alanine Aminotransferase (ALT; formerly called SGPT) - Increases up to 10x in cirrhosis, infections SGPT) - Increases up to 10x in cirrhosis, infections or tumors and up to 100x in viral or toxic hepatitisor tumors and up to 100x in viral or toxic hepatitis

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– Asparate Aminotransferase (AST; formerly called Asparate Aminotransferase (AST; formerly called

SGOT) - Increased in liver disease, but also in SGOT) - Increased in liver disease, but also in heart attacksheart attacks

– Gamma Glutamyl Transferase (GGT) - Often used Gamma Glutamyl Transferase (GGT) - Often used to monitor patients recovering from hepatitis and to monitor patients recovering from hepatitis and cirrhosiscirrhosis

– Lactate Dehydrogenase (LD) - Increased in liver Lactate Dehydrogenase (LD) - Increased in liver disease and following heart attacksdisease and following heart attacks

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryCardiac Function TestsCardiac Function Tests

– Creatine Kinase (CK) - Widely used to diagnosis Creatine Kinase (CK) - Widely used to diagnosis and monitor heart attacksand monitor heart attacks

– TroponinsTroponins Only present in heart muscle, making it a Only present in heart muscle, making it a

more accurate indicator of heart attack than more accurate indicator of heart attack than CKCK

Cardiac Troponin T (cTnT)Cardiac Troponin T (cTnT) Cardiac Troponin I (cTnI)Cardiac Troponin I (cTnI)

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryLipid Metabolism TestsLipid Metabolism Tests

– Cholesterol Cholesterol Present in all tissuesPresent in all tissues Serves as the skeleton for many hormonesServes as the skeleton for many hormones Recommended to be less than 200 mg/dL in Recommended to be less than 200 mg/dL in

adults)adults) LDL = “bad” cholesterol; HDL = “good” LDL = “bad” cholesterol; HDL = “good”

cholesterolcholesterol

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry– TriglyceridesTriglycerides

Main storage form of lipids, comprising 95% of Main storage form of lipids, comprising 95% of fat tissuefat tissue

Hyperlipidemia – having high blood levels of Hyperlipidemia – having high blood levels of triglycerides – may increase risk of heart triglycerides – may increase risk of heart attackattack

Carbohydrate Metabolism TestsCarbohydrate Metabolism Tests– Glucose - Largely regulated by insulinGlucose - Largely regulated by insulin

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryThyroid Function TestsThyroid Function Tests

– Thyroid Stimulating Hormone (TSH) - Inverse Thyroid Stimulating Hormone (TSH) - Inverse relationship to thyroid function (the higher the relationship to thyroid function (the higher the TSH, the lower the thyroid function and vice TSH, the lower the thyroid function and vice versa)versa)

– Other less common thyroid tests include T3 and Other less common thyroid tests include T3 and T4T4

– Hypothyroidism – underactive thyroid glandHypothyroidism – underactive thyroid gland– Hyperthyroidism – overactive thyroid glandHyperthyroidism – overactive thyroid gland

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistry For more information on most clinical For more information on most clinical

laboratory tests, visit:laboratory tests, visit:http://www.labtestsonline.org/http://www.labtestsonline.org/

Click on any lab test or condition or Click on any lab test or condition or disease and find all sorts of disease and find all sorts of

information!information!

Unit #6D – Clinical Laboratory Unit #6D – Clinical Laboratory Testing - Basic Clinical Testing - Basic Clinical

ChemistryChemistryPhotos of some clinical chemistry Photos of some clinical chemistry

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