Clinical Chemistry

What is clinical chemistry?

Laboratory tests that evaluate a patient’s overall organ function

What does clinical chemistry consist of?

Establishing a baseline blood work, diagnose a disease, monitor disease progress, and monitor response to drug therapy

Increased values are referred to as…

“Hyper”

Decreased values are referred to as….

“Hypo”

What does “-emia” indicate?

That protein, enzyme, or hormone is present in the blood

What is hyperbilirubinemia?

Increased bilirubin in the blood

What is hypokalemia?

Decreased potassium in the blood

What tube is used as a serum separator?

“Tiger top”

What should a tiger top tube not be used for?

Phenobarbital

How long should you centrifuge for a clinical chemistry test and on what level of RPM?

5 minutes at a higher RPM

If you use a tiger top tube or a red top tube for clinical chemistry tests, how long should you let the blood clot?

20 minutes

When should you remove serum and plasma from a clinical chemistry test after it has been centrifuged?

ASAP

What should you do with the clinical chemistry sample until you send it to the reference lab?

Keep it refrigerated or frozen

Plasma contains anit-coagulant and what 2 others?

Fibrinogen and clotting factors

Serum DOESN’T contain anti-coagulant and what 2 others?

Fibrinogen or clotting factors

What is glucose?

A sugar used as an energy source that’s absorbed from the GI tract and transported to the blood. It is a basic nutrient for tissues and cellular uptake is regulated via insulin

What are 3 sources of glucose?

Diet, glycogenolysis, and gluconeogenesis

What is glycogenolysis?

When glycogen is converted to glucose and readily available as energy

What is gluconeogenesis?

Glucose production from amino acids and fats

What are 4 diagnostic test for glucose?

Glucometer, urine glucose, blood glucose, and fructosamine

What are 4 causes of hyperglycemia?

Stress, fear, type I and II diabetes mellitus, hyperadrenocorticism (excess cortisol)

What are 6 causes of hypoglycemia?

Hypoadrenocorticism (immune mediated destruction of adrenal glands), hypothyroidism, neoplasia, sepsis, liver failure, and portosystemic shunts

What is the function of the kdiney?

Eliminates waste from the body via urine

What is the nephron and what does it include?

The functional portion of the kidney, includes the glomerulus and renal tubules

What percent of nephrons must function appropriately and efficiently?

34%

What are 3 conditions that can happen in the kidney’s?

Azotemia, renal disease, renal failure

What are the 2 kidney enzymes?

BUN and creatine

What are the characteristics of BUN?

Waste product of protein metabolism, produces ammonia (liver converts ammonia to urea → secreted by kidneys), NOT specific for renal disease

What are the characteristics of creatine?

Waste product of muscle metabolism, more specific evaluation of renal disease than BUN

What is a BUN:CREAT ratio?

Ratio of blood urea nitrogen value to creatine value

What is an adequate concentrating ability?

Sufficient, functional nephrons and blood flow

What is inadequate concentration ability?

Loss of functional nephrons, concentrating ability is lost

What is isosthenuria concentration ability?

Inability to concentrate or dilute urine, fixed USG

What is hyposthenuria concentration ability?

Able to dilute urine, unable to concentrate urine, unresponsive to ADH

What is hyposthenuria concentration ability?

Able to concentrate urine, unable to dilute urine

What are the 3 classifications of azotemia?

Pre-renal, renal, and post-renal

What is the pre-renal classification of azotemia?

Before the kidneys, dehydration, increased protein metabolism

What is the renal classification of azotemia?

75% of nephrons are damaged/non-functional, inability to adequately concentrate the urine

What is the post-renal classification of azotemia?

After the kidneys, think blocked cat and uroabdomen

What is total protein?

The measurement of all the proteins within the body

What are the 5 causes for hypoproteinemia?

Hemorrhage, inflammatory intestinal disease, nephropathy causing damage to renal tubules and glomeruli, decreased production, failure of passive transfer

What is the cause of hyperproteinemia?

Dehydration

What are the two proteins produced in the liver?

Albumin and globulin

What are the characteristics of albumin?

Osmotically active, prevents loss of substances through the kidney

What are the 3 causes of hypoalbuminemia?

Decreased production, protein losing nephropathy, and overhydration

What are the 2 causes of hyperalbuminemia?

Artifact, administration of corticosteroids

What are the characteristics of globulin?

Most proteins in the body are globulins, involved in immune system or inflammation

What are the 3 causes of hyperglobulinemia?

Hemorrhage, protein losing nephropathy, and decreased production

What are the 2 causes of hyperglobulinemia?

Neoplasia and immune/anitigen stimulation

What does A:G indicate?

Indicates increase or decrease

What are the 6 functions of the liver?

Detoxification and excretion, digestion, storage, carbohydrate metabolism, fat metabolism, protein metabolism and production

What are the 5 enzymes produced by the liver?

ALT, AST, SDH, ALP/ALKP, and GGT

Which 2 enzymes produced by the liver are liver specific?

ALT and SDH

What 3 enzymes produced by the liver are not liver specific?

AST, ALP/ALKP, and GGT

In what species does the liver produce ALT? What does ALT suggest?

Canines and felines, suggest hepatocellular damage

What does the production of AST suggest in bovine and equine? What about canines and felines?

Bovine and equine: Liver damage, canines and felines: liver disease

SDH is produced in all species, but which species is it more common?

Bovine and equine

Where is the liver enzyme ALP/ALKP found and what does an increase in it play a role in?

Liver, bone, GI, kidney, and placenta. An increase plays a role in many disease processes?

What is the liver enzyme GGT an indicator of?

Cholestatic diseases and renal tubular damage

What are the 4 different types of bilirubin?

Unconjugated, conjugated, delta, and total

What is unconjugated bilirubin?

Bilirubin that is not yet processed by the liver, it is bound to albumin and unable to be excreted via kidneys

What is conjugated bilirubin?

Bilirubin that is conjugated by the hepatocyte making it water soluble and filtered by the glomerulus

What is delta bilirubin?

Conjugated bilirubin bound to albumin

What is total bilirubin?

A combination of conjugated, unconjugated, and delta bilirubin