Clinical Chemistry

Clinical Chemistry

Branch of medical science that is involved in the analysis of biological materials; provides diagnostic results on the state of human body

Blood and Urine

Common specimen in Clinical Chemistry

Spectrophotometry

Measurement of intensity of light at selected wavelengths

Concentration

Spectrophotometer measures _____ of a colored solution

Light Source

provides incident light for the whole system

Entrance slit

reduces stray light; prevents scattered light from entering the monochromator

Monochromator

separate and transmit a certain wavelength of the spectrum

Exit slit

receives specific spectrum of light before it passes through a sample cell

Cuvette (analytical cell)

a kind of test tube designed for optical analysis

Cuvette (analytical cell)

made especially for the spectrophotometry

Cuvette (analytical cell)

where you’re going to place or contain the sample you’re going to measure in a spectrophotometer

Photodetector

converts transmitted radiant energy into an equivalent amount of electrical energy

Meter or Read-Out Device

digital display of absorbance or transmittance

Beer Lambert

Spectrophotometer applies the ________ Law

Directly, Inversely

Beer’s Law states “the concentration of a substance is _______ proportional to the amount of light absorbed or _______proportional to the amount of transmitted light.”

Formula for Concentration

Standard

Basically the control group; always given in the formula

Concentration

(c)

Absorbance/optical density (A/OD)

is synonymous to the amount of blocked light

Percent transmittance

is synonymous to the reflected light

absorbance / optical density

You need to solve for the concentration because only the ______________ of the specimen is presented in the read-out.

Routine Clin Chem Assays

Blood Glucose, Blood Lipid Profile, Kidney Function Tests, Liver Function Tests, Cardiac Function Tests

Blood Glucose

requested with diagnosis of diabetic conditions.

glycogenolysis or gluconeogenesis

Elevated Glucose eating

liver and muscles, adipose tissues

Glucose short term storage sites include ____ and _____ while long term storage sites are in ________

Normal Fasting Blood Sugar Level

60-100 mg/dL

Glucosuria

Can occur in urine if the renal threshold (160- 180 mg/dL) has been exceeded. =

Glucosuria

is the presence of blood in the urine; normal urine should not contain any glucose because our kidneys will filter our urine and will not allow glucose to pass through.

Fasting Blood Sugar

Patient should be subjected to 8 - 12 hours
of fasting before blood withdrawal.

Random Blood Sugar

With or without fasting

Oral Glucose Tolerance Test

Normally requested by pregnant patients to determine if they are suffering from Gestational Diabetes

2 Hours Post Prandial Blood Sugar

Patients are ordered to drink something and then after 2 hours, they are subjected to blood extraction.

Glycosylated Hemoglobin (HBA1c)

Measures a patient’s blood glucose in the
last 3 months.

Diabetes Mellitus

defect in the beta-cells of the pancreas.

Diabetes Mellitus

There is a decrease insulin production and
increase in blood glucose

Polyuria

excessive urination

Polydipsia

Excessive thirst

Polyphagia

Excessive eating

Hypoglycemia

abnormally low blood sugar usually resulting from excessive insulin or a poor diet

Hyperglycemia

abnormally high blood sugar usually associated with diabetes

Blood Glucose Tests

FBS, RBS, OGTT, 2hPPBS, HBA1c

9 kcal

Lipids can provide ____ of heat

Lipids

Act as primary energy source and important constituent of cellular membrane

Lipids

Insulators of the body

Triacylglycerol

Storage form; Makes serum turbid; mainly responsible for the solution’s turbidity.

increase

kung turbid gid ang sample, it means there is an _____ in TAG

High Density Lipoprotein

“good cholesterol”; Transports cholesterol back to the liver (where they will be digested/synthesized).

Low Density Lipoprotein

“bad cholesterol”; Transports cholesterol to peripheral tissues.

Total Cholesterol

Source of hormones, vitamin D, bile salt

Bile Salt

where fats/cholesterol can be emulsified.

Blood Lipid Profile Tests

TAG, HDL, LDL, Total Cholesterol

Kidney

Are considered as the body's waste sweeper

Filtering/Filtration

Main function of the kidney

Function of the kidney

Excrete what is not needed in the body and retain those of use

Nephron

Functional unit of the kidney

Urine formation by the nephron

Glomerular Filtration, Tubular Reabsorption, Tubular Secretion

Cr / CREAT

Creatinine; Waste product of muscle metabolism derived from creatinine phosphate which is stored in the muscles & is used for energy;

50%

In renal function there is ___ increase in
blood

chronic kidney problems/diseases.

Increase in creatinine is usually a sign of
____________

Blood Urea Nitrogen

BUN

Blood Urea Nitrogen

Waste product of protein catabolism;

90%

In protein catabolism, ___ of BUN is excreted

Catabolism

Breaking down of protein

Low, HIgh

___ levels seen during starvation, pregnancy, & low-protein diet. ____ levels seen in high protein diet, after steroids use, kidney disease

BUN

.Usually the very first test that indicates if you have acute kidney problems/diseases.

Azotemia

Elevation of BUN

Uremia

Azotemia + Renal Failure; accumulation in the blood of nitrogenous waste products that are usually excreted in the urine

Glomerular Filtration Rate

GFR; Estimates how much blood passes through the glomeruli each minute.

Glomerulus

found inside the nephron

Kidney Function Tests

CREATININE, BUN, GFR

Liver

synthesizes organic substances (e.g. Coagulation factors) and detoxifies the body against noxious substances.

Bilirubin

Brownish yellow pigment in the bile

B1 & B2

Bilirubin comes from old RBC _______

Yellow Baby

Bilirubin is sometimes referred to as ____ because there is a yellowish tone on the skin of a baby due to the breaking down of RBC and the subsequent release of bilirubin.

Aspartate Aminotransferase

AST; Old name is serum glutamic oxaloacetic transaminase (SGOT); can be produced in other parts of the body

Alanine Aminotransferase

ALT; Old name is serum glutamis pyruvid transaminase (SGPT); Liver specific

De Ritis Ratio

AST/ALT Ratio; helps identify the cause of hepatic disorders

Non-viral in origin

AST ALT Ratio: >1

Viral in origin

AST ALT Ratio: <1

Alkaline Phosphatase

ALP; Diagnosis of liver and bone diseases

Gamma-glutamyl Transferase

GGT; Diagnosis of chronic alcoholism resulting in liver damage

Increase in GGT

Alcoholic Patient = Liver Problem =

Cholinesterase

Assesses insecticide and pesticide poisoning; increase in the blood if there is an accidental poisoning

Hypoproteinemia

abnormally low level of protein in the blood; can indicate kidney disorders

Hyperproteinemia

High total protein in the blood; seen with chronic inflammation or infections (viral hepatitis or HIV)

Albumin

Helps keep blood from leaking out of blood vessels; carrier protein of medicines and other substances in the body

Globulins

Helps regulate the function of circulatory system

Low Albumin/Globulin Ratio

overproduction of globulins (seen in multiple myeloma or autoimmune diseases); an underproduction of albumin (seen in cirrhosis); or selective loss of albumin from
the circulation (seen in nephrotic syndrome)

High Albumin/Globulin Ratio

overproduction of Ig (seen in genetic deficiencies and leukemia)

Ig

Immunoglobulin

Prothrombin Time

PT; Test for plasma-clotting activity and reflects the activity of vitamin K-dependent clotting factors synthesized by the liver

Plasma-clotting activity

reflects how well our blood clots

Liver Function Tests

Bilirubin, Liver Enzyme Tests, Total Serum Protein Tests, Prothrombin Time

Troponin test

Most sensitive and specific test for myocardial damage;

12 hours

Peak of troponin is _____ after infarction

Myoglobin

Along with troponin, is considered a cardiac biomarker

2-3, 8-12

Myoglobin rise within ___ hours of a heart attack or other muscle injury; Peak within ____ hours;

True

Myoglobin levels generally return to normal level within a day

False

Increase in myoglobin is detectable earlier than troponin and is specific for heart damage

True

If a patient is suffering from a suspected heart attack, their blood should be taken immediately to asses the time when troponin and myoglobin peaked.