1. S ECTIONS OF THE L ABORATORY CLINICAL PATHOLOGY 1. Clinical Chemistry  BUN  Cholesterol  FBS 2. Clinical Microscopy  Analysis of body fluids  Urin analysis  Fecal anaysis  Semen analysis 3. Microbiology  Cultures (sputum, blood, urine) 4. Hematology Biggest section Includes CBC,coagulation, PT, PTT

2. B LOOD BANK Very critical section Bec. May have errors Blood typing Cross match AB Identification Goes hand in hand with serology and immunology Tests done for  MALARIA  SYPHILIS  HIV Serology/Immunology Cardiac and thyroid fxntest II. ANATOMY PATHOLOGY Histopathology Submission of tissues for tests

3. N ATURE OF R EQUEST STAT  Performed immediately and by itself.  Run control and standard  20-50% More expensive  TAT is shortened  Request is needed Today  Confusing  Performed as soon as possible, given priority  Based on “running time” Routine  Done with the batch  Wait for TAT stated by laboratory

4. V ALUES REFERENCE VALUES Better term than “normal value” Pulled value, usually 95%of population Vary in diff. hospitals but not that far SIGNIFICANT VALUES Clinical decision should be made if higher or lower than reference value Usually when 2x to 3x

5. CRITICAL VALUES  Needs immediate attention  “panic values”  Should call physician  Patient is at risk

6. R EFERENCE V ALUES Not fixed for all Should consider:  Age  Sex  Pregnancy  Diurnal Variation  Race  Blood type

7. R OUTINE E XAMINATIONS ROUTINE ADMISSION TESTS CBC, Urinalysis, Fecalysis ROUTINE CHEMISTRIES BUN, Creatinine, Glucose, Uric Acid, Cholesterol Sometimes triglycerides

8. B ASIC LAB EQUIPMENTS The Light Microscope. Colorimeters and photometers Water bath Laboratory centrifuge Balance Cold incubators refrigerators pH meters Mixers Ovens De-ionizers Safety cabinets. Glassware and plasticware

9. S AMPLING Pathologist should try to answer the question which is imposed by the clinician. Correct specimen for requested test with necessary information so that right test is carried out And result is delivered to the requesting clinician with the minimum of delay. Patient identification must be correct.

10. S PECIMEN TYPES Venous blood serum or plasma. Arterial blood. Capillary blood Urine Feces Cerebrospinal fluid Sputum and sliva Tissue and cells Aspirates (pleural fluid, ascites, joint fluid, intestinal (duodenal) fluid, pancreatic pseudocysts. Calculi

11. B LOOD SPECIMENS Serum Plasma Urine specimen Preservative may be added to prevent bacterial growth or acid may be added to stabilize metabolites. Other specimen types Dangerous specimen Labelled as “dangerous specimen” yellow sticker. Similar label should be attached on the request form. HBV and HIV

12. S AMPLING ERRORS Blood sampling techniques Prolonged stasis during venepuncture Insufficient specimen Errors in timing Incorrect specimen container In appropriate sampling site Incorrect sample storage.

13. L IPID CHEMISTRY AND CARDIOVASCULAR PROFILE Main lipids in the blood are the triglycerides and cholesterol.(phospholipids, FFA) These are insoluble in the water. Transport in the blood is via lipoproteins.(protein) 4 major classes of lipoproteins. Chylomicrons Very low density lipoproteins (VLDL) Low density lipoproteins (LDL) High density lipoproteins (HDL)

14. L IPOPROTEINS COMPOSITIONS

15. C OMPOSITION OF LIPOPROTEINS Class Diamete r (nm) % protein % cholesterol % phospholipi d % triacylglyc erol & cholesterol ester HDL 5–153330294 LDL 18–282550218 IDL 25–5018292231 VLDL 30–8010221850 Chylomicr ons 100-1000<28784

16. LIPOPROTEINS Chylomicrons carry triglycerides ( dietary fat) from the intestines to the liver, to skeletal muscle, and to adipose tissue. Very-low-density lipoproteins (VLDL) carry (newly synthesised or endogenous) triglycerides from the liver to adipose tissue and metabolized to LDL through IDL. Intermediate-density lipoproteins (IDL) are intermediate between VLDL and LDL. They are not usually detectable in the blood. Low-density lipoproteins (LDL) carry cholesterol from the liver to cells of the body. LDLs are sometimes referred to as the "bad cholesterol" lipoprotein. High-density lipoproteins (HDL) collect cholesterol from the body's tissues, and take it back to the liver. HDLs are sometimes referred to as the "good cholesterol" lipoprotein.

17. L IPOPROTEIN METABOLISM

19. 60% of plasma cholesterol is present in LDL, 25% in HDL and small quantity in VLDL. Lipoprotein metabolism is controlled by their protein component apolipoproteins. Apo A-1 in HDL and Apo B-100 in LDL are very important ones. Lipoprotein (a) in also present in human plasma. It is synthesized in the liver. Smaller but denser than LDL. Cholesterol esters are major lipids and it is an independent risk factor for IHD.

20. LDL and VLDL are associated with premature atherosclerosis. HDL high levels are negative risk factors for IHD. HYPERLIPIDEMIA Coronary heart disease Acute pancreatitis Failure to thrive and weakness Cataract

21. Endothelial dysfunction Lpid accumulation. Migration of inflammatory cells into the arterial wall. Atherosclerosis and plaque formation Plaque stability SCAD (asymptomatic) Chest pain at rest (angina, non ST elevation MI, STEMI)

22. PATHOPHYSIOLOGY Atherosclerotic plaque, rupture and thrombus formation. Obstruction of coronary circulation. Necrosis of the heart tissue. Irreversible cardiac injury if occlusion is complete for 15-20 mins. Starts from endocardium and spreads towards epicardium. If full thickness of myocardium is involved then it is transmural infarct.

23. D IAGNOSIS OF MI Detection of rise and fall of cardiac biomarker troponinT/I with one of the following: Symptoms of ischemia ECG changes Q wave

24. ECG CHANGES

25. LACTATE DEHYDROGENASE (LDH) Catalyzes the reversible oxidation of lactate to pyruvate Used to indicate AMI Is a cytoplasmic enzyme found in most cells of the body, including the heart Not specific for the diagnosis of cardiac disease

26. D ISTRIBUTION OF LD ISOENZYMES LD1 and LD2 (HHHH, HHHM) Fast moving fractions and are heat-stable Found mostly in the myocardium and erythrocytes Also found in the renal cortex LD3 (HHMM) Found in a number of tissues, predominantly in the white blood cells and brain LD4 and LD5 (HMMM, MMMM) Slow moving and are heat labile Found mostly in the liver and skeletal muscle

27. C ONSIDERATIONS IN LD ASSAYS Red cells contain 150 times more LDH than serum, therefore hemolysis must be avoided LDH has its poorest stability at 0°C Clinical Significance In myocardial infarction, LD increases 3-12 hours after the onset of pain Peaks at 48-60 hours and remain elevated for 10- 14 days In MI, LD1 is higher than LD2, thus called “flipped” LD pattern

28. FLIPPED LDH An inversion of the ratio of LD isoenzymes LD 1 and LD 2 ; LD 1 is a tetramer of 4 H–heart subunits, and is the predominant cardiac LD isoenzyme; Normally the LD 1 peak is less than that of the LD 2, a ratio that is inverted–flipped in 80% of MIs within the first 48 hrs DiffDx. LD flips also occur in renal infarcts, hemolysis, hypothyroidism, and gastric CA

29. CREATINE KINASE (CK) Is a cytosolic enzyme involved in the transfer of energy in muscle metabolism Catalyzes the reversible phosphorylation of creatine by ATP -Is a dimer comprised of two subunits, resulting in three CK isoenzymes The B, or brain form The M, or muscle form

30. Three isoenzymes isolated after electrophoresis : CK-BB (CK1) isoenzyme Is of brain origin and only found in the blood if the blood- brain barrier has been breached CK-MM (CK3) isoenzyme Accounts for most of the CK activity in skeletal muscle CK-MB (CK2) isoenzyme Has the most specificity for cardiac muscle It accounts for only 3-20% of total CK activity in the heart Is a valuable tool for the diagnosis of AMI because of its relatively high specificity for cardiac injury Established as the benchmark and gold standard for other cardiac markers

31. Clinical Significance -In myocardial infarction, CK will rise 4-6 hours after the onset of pain -Peaks at 18-30 hours and returns to normal on the third day -CK is the most specific indicator for myocardial infarction (MI)

32. CHOLESTEROL Normal values: range varies according to age Total Cholesterol: 150-250mg% Cholesterol esters: 60-75% of the total cholesterol

33. C HOLESTEROL IS ADVISED IF YOU  have been diagnosed with coronary heart disease, stroke or mini-stroke (TIA) or peripheral arterial disease (PAD)  are over 40  have a family history of early cardiovascular disease  have a close family member with cholesterol-related condition  are overweight  have high blood pressure, diabetes or a health condition that can increase cholesterol levels, such as an underactive thyroid

34. F ACTORS LEADING TO RAISED CHOLESTEROL an unhealthy diet: some foods already contain cholesterol (known as dietary cholesterol) but it is the amount of saturated fat in your diet which is more importantsaturated fat smokingsmoking: a chemical found in cigarettes called acrolein stops HDL from transporting LDL to the liver, leading to narrowing of the arteries (atherosclerosis) having diabetes or high blood pressure(hypertension)diabeteshigh blood pressure having a family history of stroke or heart disease There is also an inherited condition known as familial hypercholesterolaemia (FH). This can cause high cholesterol even in someone who eats healthy diet.

35. T RIGLYCERIDES Ester derived from glycerol and three fatty acids. Main lipids in the blood and important energy substrate. Insoluble in water. Hypertriglyceridemia Not an important risk facotr for coronary artery disease. It can cause pancreatitis when severe. Both hypertriglyceridemia and hypercholesterolemia are associated with various types of cutaneous fat deposition and xanthomatas. Hypertension Very common clinical problem. Usually essential type meaning that have no identifiable cause. Investigations for treatable causes like endocrine is necessary.

36. HYPERLIPIDEMIAS

47. L IVER Anatomy of liver

51. I.T ESTS BASED ON EXCRETORY FUNCTIONS

58. L ABORATORY RESULTS

60. II.T ESTS DUE TO DETOXIFICATION

61. T ESTS B/O S YNTHETIC FUNCTION

62. Liver is the main source of synthesis of Plasma proteins Albumin Globulin Blood clotting factors Prothrombin Factors V, VII, and X

63. S ERUM ALBUMIN * 3.5- 5.5 gm/dl SERUM GLOBULIN 2 -3.5 gm/dl TOTAL PROTEINS* 6-8 gm/dl Albumin/ Globulin ratio 1.2:1 – 2.5: 1 Prothrombin time

64. T ESTS B / O METABOLIC FUNCTIONS

65. S ERUM TRANSAMINASES S ERUM ALKALINE PHOSPHATASES

66. R EFERENCE RANGE ALT ( upto 42 U/L) AST (0-37 U/L) ALP (65-306 U/L) raised in obstructive jaundice.

67. O THER ENZYMES GGT (11-60 u/l) 5- NUCLEOTIDASE (2-17u/L) LDH (180-360 u/l)

68. GGT ( OR GGTP) G amma G lutamyl T rans p eptidase. This enzyme level is elevated in case of liver disorders. In contrast to the alkaline phosphatase, the GGT tends not to be elevated in diseases of bone, placenta, or intestine

69. P ROTHROMBIN TIME good correlation between abnormalities in prothrombin time and the degree of liver dysfunction. Expressed in seconds and compared to a normal control patient's blood SPECIALIZED TESTS serum iron, the percent of iron saturated in blood, the storage protein ferritin for hemochromatosis. accumulation of copper in the liver in wilson disease.