Clinical Pathology 1. Spill management 2. Internal Quality Control 3. External Quality Control 4. Peritoneal Fluids 5. Pleural Fluid 6. Pericardial Fluids 7. Synovial Fluids 8. WBC and their Types 9. Oncotic Pressure 10. Transudates 11. Exudates 12. Tumour Marker 13. Urine analysis with all information 14. Seman analysis 15. CSF analysis 16. Preservation of bodies in mortuary 17. Clinical Autopsy 18. Medico legal Autopsy 19. Visceral 20. Perital

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Here are your comprehensive Clinical Pathology study notes covering all 20 topics:

CLINICAL PATHOLOGY - Complete Study Notes

1. SPILL MANAGEMENT

Spill management refers to protocols for safely handling accidental release of biological, chemical, or radioactive materials in the laboratory.

Categories of Spills:

Biological spills - blood, body fluids, cultures (biohazard)
Chemical spills - acids, alkalis, solvents
Radioactive spills - radioisotope-labeled reagents

Procedure for Biological Spill (e.g., blood/body fluid):

Alert others in the area immediately
PPE - put on gloves, gown, eye protection BEFORE approaching
Contain the spill using absorbent material (paper towels, absorbent granules) - work from the outer edge inward
Decontaminate - apply 10% bleach (sodium hypochlorite) or appropriate disinfectant; leave in contact for 10-30 minutes
Clean up - wipe up using fresh absorbent material; place all waste in appropriate biohazard bag
Disinfect again - apply disinfectant to the cleaned area
Report - document the incident; complete incident report form
Seek medical advice if skin/mucous membrane exposure occurred

Chemical Spill:

Neutralize acids with sodium bicarbonate; bases with dilute acid
Use appropriate absorbent (sand/vermiculite) for solvents
Use fume hood for volatile chemicals

Large Spill (>500 mL) or Aerosol-Generating Spill:

Evacuate the room; allow 30 minutes for aerosols to settle
Notify safety officer/supervisor
Use respiratory protection

2. INTERNAL QUALITY CONTROL (IQC)

IQC is the set of procedures conducted within a laboratory to continuously assess the reliability of results before patient reports are issued.

Objective: To detect random and systematic errors in analytical processes.

Key Components:

Control Materials:

Assayed and unassayed controls
Should have the same matrix as patient samples (human serum for serum analytes)
Typically run at 2-3 levels (low, normal, high)

Levey-Jennings Chart:

Graph plotting control values (y-axis) against time (x-axis)
Mean ± 2SD and ± 3SD limits are drawn
Visual detection of trends, shifts, and outliers

Westgard Rules (Multi-Rule QC):

Rule	Warning/Rejection	Meaning
1₂s	Warning	1 control exceeds mean ± 2SD
1₃s	Rejection	1 control exceeds mean ± 3SD (random error)
2₂s	Rejection	2 consecutive controls exceed same ± 2SD limit (systematic error)
R₄s	Rejection	1 control exceeds +2SD, next exceeds -2SD (range > 4SD; random error)
4₁s	Rejection	4 consecutive controls exceed same ± 1SD limit (systematic error)
10x̄	Rejection	10 consecutive controls on same side of mean (systematic error)

Types of Errors Detected:

Random error - imprecision; detected by 1₃s, R₄s rules
Systematic error - bias/drift; detected by 2₂s, 4₁s, 10x̄ rules

Six Sigma in QC: Sigma metric = (TEa - |bias|) / CV; determines how many controls are needed.

3. EXTERNAL QUALITY CONTROL (EQC) / External Quality Assessment (EQA)

EQC evaluates laboratory performance against external standards; also called Proficiency Testing (PT).

Types:

External Quality Assessment Schemes (EQAS) - distributed by national/international bodies (e.g., CAP, CMPT, NEQAS, NABL in India)
Interlaboratory comparison - same sample sent to multiple laboratories

Process:

External organization sends unknown samples (lyophilized or liquid)
Laboratory analyzes them alongside routine specimens using standard methods
Results returned to organizing body
Performance assessed by comparison with peer group (same instrument/reagent) or all-laboratory mean
Feedback report issued with Z-scores and performance rating

Z-score: (Lab result - Target value) / Standard deviation of all labs

Acceptable: |Z| ≤ 2
Warning: |Z| = 2-3
Unacceptable: |Z| > 3

Purposes:

Identify systematic errors not detected by IQC
Allow comparison between laboratories
Accreditation requirement (NABL, ISO 15189)
Education and quality improvement

4. PERITONEAL FLUIDS

Normal: Up to 50 mL of fluid in the peritoneal (mesothelial-lined) cavity; ultrafiltrate of plasma dependent on vascular permeability and hydrostatic/oncotic pressure.

Pathological accumulation = Ascites

Classification:

Transudates - increased hydrostatic pressure or decreased plasma oncotic pressure
- Causes: CHF, hepatic cirrhosis, hypoproteinemia (nephrotic syndrome)
Exudates - increased capillary permeability or decreased lymphatic resorption
- Causes: bacterial peritonitis (primary/secondary), TB, neoplasms (hepatocellular carcinoma, ovarian carcinoma, peritoneal metastases), pancreatitis, bowel rupture

Best Discriminator - Serum-Ascites Albumin Gradient (SAAG):

SAAG = Serum albumin - Ascitic fluid albumin
SAAG ≥ 1.1 g/dL → Portal hypertension (transudate) → CHF, cirrhosis
SAAG < 1.1 g/dL → Non-portal cause (exudate) → Infection, malignancy, TB
Diagnostic accuracy: 98% (vs. 52-80% for protein-based criteria)

Laboratory Tests on Ascitic Fluid:

Cell count and differential
Total protein, albumin (for SAAG)
LDH, glucose
Culture and sensitivity (aerobic, anaerobic, TB)
Cytology (malignancy)
Amylase (pancreatitis)
Triglycerides (chylous ascites)
Bilirubin ratio (ascitic/serum ≥ 0.6 = exudate)
Henry's Clinical Diagnosis and Management by Laboratory Methods, p. 600

5. PLEURAL FLUID

Anatomy: The pleural cavity is a potential space lined by mesothelium of visceral and parietal pleurae. Normally contains a small amount of plasma filtrate.

Production: From parietal pleura capillaries; reabsorbed by lymphatics/venules of visceral pleura.

Effusion: Accumulation due to imbalance of production vs. reabsorption.

Specimen Collection: Thoracentesis (diagnostic + therapeutic). Use EDTA tube for cell counts; heparinized tubes for other tests. Inoculate culture bottles at bedside.

Classification of Pleural Effusions (Light's Criteria for Exudate): Any ONE criterion = exudate:

Pleural protein/Serum protein > 0.5
Pleural LDH/Serum LDH > 0.6
Pleural LDH > 2/3 upper limit of normal serum LDH

Feature	Transudate	Exudate
Causes	CHF, cirrhosis, nephrotic syndrome	Infection, malignancy, TB, rheumatoid, PE
Protein	< 3 g/dL	> 3 g/dL
LDH	Low	High
Glucose	Normal	Low (especially rheumatoid, empyema)
pH	> 7.3	< 7.3 (empyema, malignancy)

Cellular Differential Significance:

Neutrophilia (>50%) → Bacterial pneumonia, pulmonary infarction, pancreatitis, early TB
Lymphocytosis (>50%) → TB, viral, lymphoma, malignancy, rheumatoid
Eosinophilia → Air/blood in pleural space, drugs, parasites
Mesothelial cells → Present in transudates; absent in TB
Malignant cells → Metastatic carcinoma (breast, lung most common), lymphoma, mesothelioma

Special Tests:

ADA (adenosine deaminase) elevated → TB pleuritis
Amylase elevated → Pancreatitis, esophageal rupture
Triglycerides >110 mg/dL → True chylothorax
Low glucose → Rheumatoid pleuritis, empyema, malignancy, TB
Interferon-γ elevated → TB

Cytology Images:

Mesothelial cells in pleural fluid

Breast carcinoma cells in pleural fluid

6. PERICARDIAL FLUID

Normal: 10-50 mL of transudative fluid in the pericardial space.

Causes of Pericardial Effusion:

Infectious: Viral (enterovirus most common), bacterial, TB, fungal
Autoimmune: SLE, rheumatoid arthritis
Neoplastic: Primary (mesothelioma) or metastatic
Metabolic: Renal failure, myxedema
Traumatic: Post-pericardiotomy syndrome, myocardial infarction (Dressler syndrome)
Drug-induced
HIV (commonly asymptomatic; may be associated with primary effusion lymphoma)
Idiopathic

Post-Pericardiotomy Syndrome:

Develops days to weeks after cardiac surgery
Exudative, often serosanguineous, pH > 7.4, normal glucose
Immune-mediated (elevated anti-myocardial antibodies, decreased complement)

Specimen: Pericardiocentesis - submitted for cell count, protein, LDH, glucose, culture, cytology (same criteria as pleural fluid for transudate/exudate distinction).

Cardiac Tamponade - pericardial fluid compresses the heart; requires urgent drainage.

7. SYNOVIAL FLUID

Physiology: Ultrafiltrate of plasma + hyaluronic acid from synoviocytes. Normal: clear, pale yellow, viscous, < 3.5 mL; glucose equals blood glucose; WBC < 150/mL.

Classification of Synovial Fluid by Disease Group:

Finding	Normal	Group I (Non-inflammatory)	Group II (Inflammatory)	Group III (Infectious)	Group IV (Hemorrhagic)
Clarity	Transparent	Transparent	Transparent/opaque	Opaque	Opaque
Color	Clear/pale yellow	Xanthochromic	Yellow-white	White	Red-brown
WBCs/mL	0-150	< 3,000	3,000-75,000	50,000-200,000	50-10,000
PMNs %	< 25	< 30	> 50	> 90	< 50
Glucose diff	0-10 mg/dL	0-10	0-40	20-100	0-20

Group Examples:

Group I: Osteoarthritis, trauma
Group II: Rheumatoid arthritis, gout, pseudogout, SLE, Reiter's
Group III: Septic arthritis (bacterial)
Group IV: Hemarthrosis, trauma, coagulation disorders

Crystal Analysis (Polarized Microscopy):

Gout - Monosodium urate (MSU) crystals: needle-shaped, negatively birefringent (yellow when parallel to compensator)
Pseudogout - Calcium pyrophosphate (CPP): rhomboid-shaped, positively birefringent (blue when parallel to compensator)
Cholesterol crystals: notched rectangular plates; found in rheumatoid, TB
Hydroxyapatite: non-birefringent; identified by alizarin red stain

Viscosity: Normal SF is highly viscous (forms a long string - "string test"). Reduced in inflammatory conditions due to hyaluronidase depolymerizing hyaluronic acid.

Mucin Clot Test: Good clot = normal viscosity; poor clot = inflammatory.

8. WHITE BLOOD CELLS (WBCs) AND THEIR TYPES

Normal Total WBC Count: 4,000-11,000/µL (4-11 × 10⁹/L)

Types and Normal Differential:

Cell Type	%	Absolute Count	Function
Neutrophils	50-70%	2,000-7,500/µL	First responders to bacterial/fungal infection; phagocytosis
Lymphocytes	20-40%	1,000-4,800/µL	Adaptive immunity (T cells, B cells, NK cells)
Monocytes	2-8%	200-900/µL	Phagocytosis; become macrophages in tissue; antigen presentation
Eosinophils	1-4%	40-500/µL	Allergic reactions, parasitic infections
Basophils	0-1%	0-100/µL	Allergic reactions (IgE-mediated); release histamine/heparin

Morphological Features:

Neutrophil: Multi-lobed nucleus (2-5 lobes), pink cytoplasm, fine granules. Band form = immature/not yet segmented
Lymphocyte: Round nucleus, scant sky-blue cytoplasm; small (T, B) or large granular (NK cell)
Monocyte: Kidney-shaped or horseshoe nucleus, abundant grey-blue cytoplasm, vacuoles; largest WBC
Eosinophil: Bilobed nucleus, large bright orange-red granules in cytoplasm
Basophil: Bilobed/irregular nucleus obscured by dark purple-black granules

Clinical Significance:

Neutrophilia → Bacterial infection, inflammation, steroids, CML
Neutropenia → Viral infection, drugs, aplastic anemia, autoimmune
Left shift → Band forms > 10%; severe infection (band + metamyelocytes)
Lymphocytosis → Viral infections (EBV, CMV, HIV), CLL, pertussis
Eosinophilia → NAACP: Neoplasm, Allergy/Asthma, Addison's, Collagen vascular, Parasites
Basophilia → CML (hallmark), polycythemia vera, myxedema
Monocytosis → TB, SBE, malaria, recovery phase of agranulocytosis
Leukemoid reaction → WBC > 50,000 due to non-leukemic cause (infection, tumor)

9. ONCOTIC PRESSURE

Definition: Also called colloid osmotic pressure (COP); the osmotic pressure exerted by large molecules (primarily plasma proteins) that do not pass through semi-permeable capillary membranes.

Key Facts:

Normal plasma oncotic pressure: ~25-28 mmHg
Albumin accounts for ~75% of total plasma oncotic pressure
Albumin synthesis is increased when oncotic pressure falls and decreased by IL-6/cytokines

Starling Forces (Capillary Fluid Exchange):

Net filtration = (Pc - Pi) - (πc - πi)

Where:

Pc = capillary hydrostatic pressure (pushes fluid OUT)
Pi = interstitial hydrostatic pressure (pushes fluid IN)
πc = plasma oncotic pressure (pulls fluid IN)
πi = interstitial oncotic pressure (pulls fluid OUT)

Clinical Relevance:

Low oncotic pressure (hypoalbuminemia) → fluid leaks out of capillaries → edema/effusions
Conditions causing decreased oncotic pressure:
- Liver disease (decreased albumin synthesis)
- Nephrotic syndrome (protein loss in urine)
- Malnutrition/cachexia
- Protein-losing enteropathy

10. TRANSUDATES

Definition: Fluid accumulation caused by systemic factors that alter hydrostatic or oncotic pressure, without local tissue or membrane injury.

Mechanism:

Increased hydrostatic pressure → pushes fluid out (e.g., CHF, portal hypertension)
Decreased plasma oncotic pressure → less fluid drawn back (e.g., hypoalbuminemia)

Causes (by site):

Site	Cause
Pleural	CHF (most common), cirrhosis, nephrotic syndrome, Meigs' syndrome
Peritoneal	CHF, cirrhosis, nephrotic syndrome
Pericardial	Hypothyroidism, uremia (early), CHF
Synovial	Osteoarthritis (Group I)

Laboratory Features of Transudates:

Parameter	Transudate
Protein	< 3.0 g/dL (pleural/pericardial/peritoneal)
LDH	< 200 U/L
Pleural protein/Serum protein	< 0.5
Pleural LDH/Serum LDH	< 0.6
Specific gravity	< 1.015
Cells	Few, mainly mesothelial/macrophages
Appearance	Clear, pale yellow, straw-colored
SAAG (ascites)	≥ 1.1 g/dL

11. EXUDATES

Definition: Fluid accumulation caused by local tissue injury, inflammation, or impaired lymphatic drainage, leading to increased capillary permeability.

Mechanism:

Increased capillary permeability → protein leaks out
Decreased lymphatic resorption → fluid accumulates

Causes:

Site	Cause
Pleural	Pneumonia (parapneumonic), TB, malignancy, PE, rheumatoid, SLE
Peritoneal	Bacterial peritonitis, TB, malignancy, pancreatitis
Pericardial	Viral/bacterial/TB pericarditis, malignancy, uremia (late), post-MI
Synovial	RA, gout, septic arthritis, reactive arthritis (Group II, III)

Laboratory Features of Exudates (Light's Criteria - Any ONE):

Parameter	Exudate
Pleural protein/Serum protein	> 0.5
Pleural LDH/Serum LDH	> 0.6
Pleural LDH	> 2/3 upper limit serum LDH
Protein	> 3.0 g/dL
Specific gravity	> 1.018
Cells	Many WBCs; type depends on cause
Appearance	Turbid, may be hemorrhagic
SAAG (ascites)	< 1.1 g/dL

Special Exudate Types:

Empyema - pus in pleural space; WBC > 50,000; glucose very low; pH < 7.2
Chylothorax - milky fluid; triglycerides > 110 mg/dL; from thoracic duct disruption
Hemothorax - blood; hematocrit of fluid/blood > 0.5
Pseudochylothorax - cholesterol-rich; long-standing TB or RA

12. TUMOUR MARKERS

Definition: Substances produced by tumor cells or by the body in response to tumors; detected in blood, urine, or tissue.

"Ideal" Tumour Marker Properties:

Produced only by tumor
Detectable at low volumes (sensitive)
High specificity (not elevated in benign conditions)
Correlates with tumor burden/stage
Predictive of prognosis
Response to treatment reflected rapidly
Cheap and easy to measure

Major Tumour Markers:

Marker	Associated Tumors	Normal Value	Notes
AFP (Alpha-fetoprotein)	Hepatocellular carcinoma, germ cell tumors	< 10 ng/mL	Also elevated in liver cirrhosis, pregnancy
CEA (Carcinoembryonic antigen)	Colorectal, lung, breast, gastric	< 2.5-5 ng/mL	Monitoring recurrence; non-specific
PSA (Prostate-specific antigen)	Prostate carcinoma	< 4 ng/mL	Screening + monitoring; elevated in BPH, prostatitis
CA-125	Ovarian carcinoma	< 35 U/mL	Monitoring treatment; elevated in endometriosis
CA 19-9	Pancreatic, biliary carcinoma	< 37 U/mL	Not useful for screening
hCG (human chorionic gonadotropin)	Choriocarcinoma, testicular germ cell	< 5 mIU/mL	Also gestational trophoblastic disease
LDH	Lymphoma, germ cell tumors, leukemia	100-245 U/L	Non-specific; indicates tumor burden
Beta-2 microglobulin	Myeloma, lymphoma, leukemia	< 2 mg/L	Prognosis in myeloma
Calcitonin	Medullary thyroid carcinoma	< 10 pg/mL	Screening in MEN2 families
Thyroglobulin	Differentiated thyroid carcinoma	Varies	Monitoring after thyroidectomy
Chromogranin A	Neuroendocrine tumors	< 100 ng/mL	Carcinoid, pheochromocytoma
CA 15-3	Breast carcinoma	< 30 U/mL	Monitoring, not screening
NSE (Neuron-specific enolase)	Small cell lung cancer, neuroblastoma	< 12.5 ng/mL

Key Principles:

No tumour marker is 100% specific
Used for monitoring treatment response and recurrence, NOT primarily for screening (exception: PSA in prostate, AFP in cirrhosis patients)
Interpret in context of clinical and imaging findings
Tietz Textbook of Laboratory Medicine, 7th Edition, p. 1462-1481

13. URINE ANALYSIS - Complete

Specimen Types:

Random: Most common; used for routine screening
First morning: Most concentrated; best for proteinuria, pregnancy test, TB
Midstream clean-catch: For culture; avoids contamination
24-hour urine: Quantitative measurements (protein, creatinine, electrolytes)
Catheter specimen: For hospitalized patients

Preservation: Refrigerate at 2-8°C if not processed within 2 hours; chemical preservatives: boric acid (culture), formalin (cells/casts), thymol.

A. PHYSICAL EXAMINATION

Property	Normal	Abnormal	Significance
Volume	600-2500 mL/24h	Polyuria/Oliguria	DM, DI, renal failure
Color	Pale-dark yellow	Red, brown, green, black	Hematuria, bilirubinuria, alkaptonuria
Clarity	Clear	Turbid	Infection, pyuria, phosphaturia
Odor	Faintly aromatic	Fruity (ketones), ammoniacal (UTI), mousy (PKU)	Metabolic states
Specific Gravity	1.003-1.030	Fixed 1.010 = isosthenuria	Renal tubular dysfunction
pH	4.5-8.0	< 4.5 or > 8.0	Metabolic acidosis/alkalosis, UTI

Urine Colors and Causes:

Red/pink → Hematuria, hemoglobinuria, myoglobinuria, beets
Orange → Urobilinogen, phenazopyridine, rifampin
Dark brown → Bilirubin, myoglobin
Green/blue → Biliverdin, Pseudomonas, methylene blue
Black → Melanin (melanoma), alkaptonuria, methemoglobin
Milky white → Chyluria, pyuria, lipiduria

B. CHEMICAL EXAMINATION (Dipstick)

Test	Normal	Significance
pH	4.5-8.0	See above
Protein	Negative (trace)	Glomerulonephritis, nephrotic syndrome, DM nephropathy, pre-eclampsia
Glucose	Negative	DM (blood glucose > renal threshold ~180 mg/dL), renal glycosuria
Ketones	Negative	DKA, starvation, prolonged fasting, alcoholism, low-carb diet
Blood/Hb	Negative	Hematuria, hemoglobinuria, myoglobinuria
Bilirubin	Negative	Conjugated hyperbilirubinemia (hepatocellular, obstructive disease)
Urobilinogen	0.1-1.0 EU/dL	Elevated: hemolysis, liver disease; Absent: obstructive jaundice
Nitrite	Negative	Gram-negative bacteriuria (E. coli, Klebsiella, Proteus)
Leukocyte esterase	Negative	Pyuria (UTI, interstitial nephritis); sensitivity ~75%
Specific gravity	1.003-1.030	Renal concentrating ability

Note on Proteins:

Dipstick detects albumin only; Bence Jones protein (immunoglobulin light chains in myeloma) requires heat precipitation or electrophoresis
24-hr protein: Normal < 150 mg/day; Nephrotic syndrome > 3.5 g/day

Glucose:

Dipstick (glucose oxidase) specific for glucose; does NOT detect galactose, fructose, lactose (detected by Clinitest/Benedict's)

C. MICROSCOPIC EXAMINATION

Cells:

RBCs - Normal: 0-2/HPF. Hematuria if > 3 RBCs/HPF. Dysmorphic RBCs (acanthocytes) → glomerulonephritis
WBCs - Normal: 0-5/HPF. Pyuria if > 5/HPF → UTI, pyelonephritis, interstitial nephritis
Epithelial cells - Renal tubular epithelial (RTE) cells: tubular damage, nephrotic syndrome
Squamous cells - contamination from genital tract
Transitional cells - from ureter/bladder/urethra; malignancy if in clusters

Casts: Cylindrical molds formed in distal tubules/collecting ducts (Tamm-Horsfall protein as matrix)

Cast Type	Significance
Hyaline	Normal (exercise, dehydration, low flow)
RBC casts	Glomerulonephritis (pathognomonic)
WBC casts	Pyelonephritis, interstitial nephritis
Granular casts	Tubular damage, degenerated cellular casts
Waxy/Broad casts	Advanced renal failure (chronic kidney disease)
Fatty casts	Nephrotic syndrome (maltese cross/polarized light)
Tubular cell casts	Acute tubular necrosis
Bacterial casts	Bacterial infection of tubules

Crystals:

Normal/Acid urine: Uric acid (rhomboid), calcium oxalate (envelope-shaped), amorphous urates
Normal/Alkaline urine: Triple phosphate (coffin-lid), calcium carbonate, amorphous phosphates
Abnormal: Cystine (hexagonal) → cystinuria; Tyrosine/leucine → liver failure; Cholesterol → nephrotic syndrome; Drug crystals (e.g., sulfonamides, acyclovir, indinavir)

Organisms:

Bacteria → UTI
Yeast → Candida UTI; contamination
Trichomonas vaginalis → parasitic infection
Schistosoma haematobium eggs → hematuria in endemic areas

Other structures:

Mucus threads, sperm, fat globules (lipiduria)

14. SEMEN ANALYSIS

Indication: Male infertility workup, post-vasectomy confirmation, forensic purposes.

Collection:

Abstinence 2-5 days before collection
Collect by masturbation in sterile container
Analyze within 60 minutes of collection
Keep at body temperature (20-37°C) during transport
At least 2 samples, 1-3 months apart

Normal Values (WHO 2021 Reference Ranges - Lower Reference Limits):

Parameter	Normal (5th percentile)
Volume	≥ 1.4 mL
pH	7.2-8.0
Sperm concentration	≥ 16 × 10⁶/mL
Total sperm count	≥ 39 × 10⁶ per ejaculate
Total motility (PR + NP)	≥ 42%
Progressive motility (PR)	≥ 30%
Vitality	≥ 54% live
Morphology (Kruger/strict criteria)	≥ 4% normal forms
WBCs (leukocytes)	< 1 × 10⁶/mL

Terminology:

Term	Definition
Normozoospermia	All parameters normal
Oligozoospermia	Sperm concentration < 16 × 10⁶/mL
Asthenozoospermia	Reduced motility (< 42% total, < 30% progressive)
Teratozoospermia	Abnormal morphology < 4%
Azoospermia	No sperm in ejaculate
Oligoasthenoteratozoospermia (OAT)	All three defects combined
Leukocytospermia	WBCs > 1 × 10⁶/mL
Hypospermia	Volume < 1.4 mL
Aspermia	No ejaculate
Necrozoospermia	All sperm non-viable/immotile
Cryptozoospermia	Occasional sperm found only after centrifugation

Morphology (Kruger Strict Criteria):

Oval head (2.5-3.5 µm wide, 3.5-5 µm long), regular contour
Midpiece: < 1 µm wide, < 3 µm long
Tail: > 45 µm long, no coiling
Head defects: large, small, tapering, round, amorphous, double heads
Neck/midpiece defects: bent neck, thick/irregular midpiece
Tail defects: short, bent, multiple

Sperm Motility Grades (WHO):

PR (Progressive): Moving actively, forward
NP (Non-Progressive): Moving but not forward
IM (Immotile): No movement

Computer-Assisted Semen Analysis (CASA): Automated assessment; more objective and reproducible.

Leukocyte Analysis: Peroxidase staining differentiates WBCs (peroxidase-positive granulocytes) from immature germ cells (peroxidase-negative) when round cells are seen.

15. CSF ANALYSIS

Indications for Lumbar Puncture: Meningitis, encephalitis, SAH, demyelinating disease, malignancy (CNS involvement), Guillain-Barré, multiple sclerosis.

Contraindications: Raised ICP (papilledema), bleeding disorder, local infection at LP site, posterior fossa lesions.

Tubes collected:

Tube 1: Biochemistry (protein, glucose)
Tube 2: Microbiology (culture, Gram stain)
Tube 3: Cell count/Cytology (last tube to reduce RBC contamination artifact)
Tube 4 (if needed): Flow cytometry, oligoclonal bands

Normal CSF Values:

Parameter	Normal Value
Appearance	Clear and colorless (like "gin water")
Opening pressure	70-180 mmH₂O
Volume	100-150 mL total
WBC	0-5/µL (all mononuclear)
RBC	0
Protein	15-45 mg/dL
Glucose	50-80 mg/dL (60-70% of serum glucose)
CSF:Serum glucose	0.6-0.8
Chloride	120-130 mEq/L

CSF in Different Diseases:

Disease	Appearance	Pressure	WBC	Cell Type	Protein	Glucose
Normal	Clear	Normal	< 5	Mononuclear	15-45	Normal
Bacterial meningitis	Turbid/purulent	Raised	100s-1000s	Neutrophils (>80%)	High	Very low
Viral meningitis	Clear/slight turbid	Slightly raised	10-1000	Lymphocytes	Normal/slightly high	Normal
TB meningitis	Xanthochromic/slight turbid	Raised	10-500	Lymphocytes	High	Very low
Fungal meningitis	Clear/turbid	Raised	Variable	Lymphocytes	High	Low
SAH	Bloody → xanthochromic	Raised	RBCs present	-	High	Normal
Guillain-Barré	Clear	Normal	Normal	-	Very high	Normal
MS	Clear	Normal	Slight lymphocytosis	Lymphocytes	Slightly high	Normal

Xanthochromia: Yellow discoloration from oxyhemoglobin/bilirubin; indicates SAH (not traumatic tap). Appears 2-4 hours after SAH; persists up to 2 weeks.

Traumatic Tap vs SAH:

Traumatic tap: RBC count decreases from tube 1→3; no xanthochromia; clotting
SAH: RBC count equal in all tubes; xanthochromia; no clotting

Special Stains/Tests:

Gram stain → bacterial meningitis
India ink → Cryptococcus
AFB stain → TB meningitis
Culture, PCR
Glucose (compare with serum drawn within 30 min)
Oligoclonal bands + IgG index → MS
β2-transferrin (CSF-specific protein) → CSF leak diagnosis
14-3-3 protein, RT-QuIC → Prion disease (CJD)

Cytology: Malignant cells indicate CNS metastases or primary CNS tumors

Amebic Meningoencephalitis (Naegleria fowleri):

Neutrophilic pleocytosis, decreased glucose, elevated protein, RBCs present
Gram stain always negative
Motile trophozoites on wet mount/phase-contrast microscopy
Acridine orange: amebas = brick red, leukocytes = bright green

16. PRESERVATION OF BODIES IN MORTUARY

Purposes: Prevent decomposition, preserve for autopsy/identification, education, medico-legal evidence.

Methods of Body Preservation:

A. Refrigeration (Cold Storage)

Most common and standard method in mortuaries
Temperature: 0-4°C (32-39°F)
Slows but does not stop decomposition
Body preserved for up to 2-3 weeks
Body bags or covered trays; separate storage for unidentified/decomposed bodies
Mortuary should have: good lighting, equipment, cold storage facility, proper drainage system, adequate manpower

B. Embalming

Arterial embalming: Formaldehyde-based solution (formalin 4-10%) injected into arterial system (commonly femoral artery); drain from jugular/femoral vein
Cavity embalming: Trocar/aspirator used to remove organs; cavity fluid instilled
Surface embalming: For exposed areas/skin grafts
Preserves body for longer periods (weeks to months) for repatriation, teaching purposes, open-casket funerals

C. Chemical Fixation (Formalin)

10% neutral buffered formalin
Used for organs/tissue specimens
Cross-links proteins, prevents autolysis and bacterial decomposition
Standard for histopathology specimens

D. Storage in Glycerine

Used for long-term anatomical specimens

E. Freeze-Drying (Lyophilization)

For long-term museum/educational specimens

Mortuary Requirements:

Cold room with individual storage units
Running water and drainage
Post-mortem table (stainless steel, perforated)
Good ventilation and lighting (daylight preferred for autopsy)
Weighing scales, measuring equipment
Specimen containers and fixatives
PPE for staff (gloves, gown, face shield, boots)

Body Identification in Mortuary:

Tagged on admission with name, age, date, case number
Clothes and valuables documented and stored separately

17. CLINICAL (PATHOLOGICAL) AUTOPSY

Definition: Post-mortem examination conducted by the Department of Pathology to determine the cause of death and nature of disease. Also called hospital autopsy or consent autopsy.

Purpose:

Determine cause of death (academic, research, quality audit)
Confirm or challenge clinical diagnosis
Identify unexpected findings
Teach pathology to medical students
Audit hospital clinical performance
Research purposes (genetics, epidemiology)

Authorization: Written consent of next of kin is required. No police involvement.

Scope: May be limited (partial) autopsy of a specific organ or cavity based on family consent.

Procedure:

Review clinical history - notes, investigations, imaging
External examination - height, weight, nourishment, identification marks, jaundice, pallor, edema, injuries
Internal examination:
- Cranial cavity: Y-shaped or Kerning incision on scalp; calvarium removed; brain removed, weighed, fixed in formalin
- Chest cavity: Y-shaped thoracic incision (shoulders to pubic symphysis with deviation around umbilicus); sternum and ribs reflected; pleurae, pericardium, heart, lungs examined
- Abdominal cavity: Liver, spleen, kidneys, pancreas, GI tract, adrenals examined
- All organs weighed and sampled
Histopathology: Tissue blocks taken for microscopy
Microbiology/Toxicology: Samples taken if relevant
Reconstruction: Organs replaced; body sutured; presentable for family
Report issued - macroscopic + histopathological findings + cause of death

Limitations: Declining autopsy rates globally; cultural/religious objections; consent refusal.

18. MEDICO-LEGAL (FORENSIC) AUTOPSY

Definition: Post-mortem examination ordered by law enforcement/judicial authority to investigate suspicious, sudden, unnatural, or violent deaths.

Authority: Requested by Police Officer (minimum ASI rank) or Magistrate (in certain cases). No consent of relatives required. Conducted by Forensic Medicine Department.

Indications (Deaths requiring ML autopsy):

Unnatural deaths: homicide, suicide, accident
Sudden unexpected deaths
Deaths in custody/prison/hospital (under suspicious circumstances)
Unknown cause of death
Deaths from medical negligence
Exhumation cases
Bodies found without identification

Objectives:

Establish identity of deceased (if unknown)
Determine cause of death
Determine manner of death (natural/accidental/suicidal/homicidal)
Estimate time since death (time of death)
Determine viability in newborns
Preserve trace evidence and viscera
Reconstruct accident/crime scene from injuries

Preparation:

Investigating Officer fills 'Request for Postmortem' performa
Body should be identified by IO and witnesses
Unknown bodies: photographs + fingerprints taken; 5+ identification marks noted
Conducted in mortuary (government hospital); done in daytime (natural light preferred)
No unauthorized persons allowed; IO may be present

Procedure:

External Examination:

Age, sex, race, physique, height, weight, nourishment
Congenital anomalies
Clothing: examined for bloodstains, tears/cuts (correlated with injuries)
Paper bags on hands (not plastic - moisture/condensation destroys evidence) in violent deaths
Body wrapped in clean white sheet

Gunshot deaths/severely burnt bodies: X-rays mandatory (bullet may appear to exit but remains inside; semi-jacketed bullet jacket may remain while lead exits)

Internal Examination: Same as clinical autopsy but with additional forensic considerations

Collect blood, urine, vitreous humor, bile
Collect viscera (liver, kidney, stomach + contents, intestine portion) for toxicology
Bone marrow, hair, nails, maggots for additional analysis

Report (Postmortem Examination Report) includes:

Identity of deceased
External findings
Internal findings by cavity
Cause of death (Immediate → Antecedent → Underlying)
Manner of death
Time since death
Opinion on other queries by IO

Difference: Clinical vs. Medico-Legal Autopsy:

Feature	Clinical Autopsy	Medico-Legal Autopsy
Department	Pathology	Forensic Medicine
Authority	Family consent	Police/Magistrate order
Consent	Required	Not required
Scope	May be partial	Always complete
Objectives	Cause of death, research, audit	Cause, manner, time of death + evidence
Report goes to	Clinicians, hospital	Investigating Officer + Court
Evidence collection	Not mandatory	Mandatory

19. VISCERAL AUTOPSY

Definition: Examination of the viscera (internal organs) removed during autopsy, for toxicological and histological analysis. Also refers to the systematic internal examination of body cavities and organs.

Viscera Preservation for Toxicology: After removal, organs are preserved for chemical/toxicological analysis when poisoning is suspected.

Organs collected for toxicology:

Stomach + contents (most important for ingested poisons)
Liver (~500 g of right lobe)
Kidneys (one complete)
Spleen (whole)
Brain (portion)
Blood (from heart and peripheral site separately, ~50 mL each)
Urine (all available)
Bile (all available)
Intestinal contents (portion of ileum with contents, tied at both ends)
Vitreous humor (10 mL from both eyes)

Containers for Viscera:

Wide-mouthed glass jars with airtight lids (not plastic - may absorb certain toxins)
Each organ in separate container, properly labeled
Sent to Chemical Examiner / Forensic Science Laboratory

Preservatives for Viscera:

Situation	Preservative
Routine toxicology	Saturated salt solution (sodium chloride) - most common
Alcohol suspected	No preservative (preservative itself may be alcohol-based)
Carbon monoxide	Sent fresh; no preservative
Biological agents	Formaldehyde (but not for toxicology)

Important: Formalin is NOT used for toxicological viscera (it destroys many toxins and interferes with analysis). Saturated common salt (NaCl) is the standard preservative.

Chain of Custody: Critical - sealed containers with labels, signatures; documented transit to forensic lab; tampering must be excluded.

Systematic Cavity Examination (Visceral Examination):

Cranial cavity → Brain, meninges, pituitary
Thoracic cavity → Heart, lungs, great vessels, trachea, esophagus, thymus
Abdominal cavity → Liver, spleen, kidneys, adrenals, pancreas, GIT
Pelvic cavity → Bladder, prostate/uterus+ovaries, rectum
Neck structures → Thyroid, larynx, cervical spine

Organ Weights (Normal Approximate):

Organ	Normal Weight
Brain	1200-1400 g
Heart	250-350 g
Liver	1400-1600 g
Kidneys	120-150 g each
Spleen	100-150 g
Lungs	300-400 g each
Thyroid	20-35 g
Adrenals	4-6 g each

20. PERINATAL AUTOPSY

(Note: "Perital" in your list likely refers to Perinatal Autopsy)

Definition: Post-mortem examination of stillbirths (>22 weeks gestation) and neonatal deaths (within 28 days of birth), to determine cause of death, gestational age, viability, and presence of congenital anomalies.

Indications:

Stillbirth / intrauterine fetal death (IUFD)
Neonatal death
Congenital malformations
Perinatal asphyxia
Hydrops fetalis
Suspected TORCH infections
Chromosomal abnormalities

Special Features (Differs from Adult Autopsy):

Viability Tests: Used to determine if a live birth preceded death (medico-legal significance):

Hydrostatic (Docimasia) test (Breslau's test):
- Lungs of a stillborn baby sink in water
- Lungs of a baby that breathed float (air in alveoli)
- If lung floats: aerated = live birth occurred
- Limitation: False positive if putrefaction (decomposition) has occurred
Stomach-intestinal test: Contents (air/food) indicate live birth
Ear test (Simon's test): Air in middle ear with tympanic membrane distension

Gestational Age Assessment (if not known clinically):

Crown-heel length
Foot length
Head circumference
Weight
Ossification centers (radiology)
External features (ear cartilage, testicular descent, breast tissue, plantar creases)

Examination includes:

Macroscopic external + internal examination
Placental examination (weight, infarcts, velamentous cord, amnion/chorion)
Histopathology - all major organs sampled
Cytogenetics - karyotype from skin fibroblasts
Microbiology - TORCH, bacteria
Biochemistry - metabolic disorders (dried blood spots, Guthrie card)
Photography - external malformations, dysmorphic features

Placental Examination:

Normal weight: ~1/7th of fetal weight
Abnormalities: Velamentous cord, abruptio placentae, chorioamnionitis, placental infarcts, hydrops, tumors

Cause of Death Categories:

Congenital anomalies (chromosomal, structural)
Prematurity-related complications
Asphyxia/hypoxia-ischemia
Infection (chorioamnionitis, congenital infection)
Maternal conditions (pre-eclampsia, DM)
Unexplained (SIDS, SIDS-like)

QUICK REFERENCE SUMMARY TABLE

Topic	Key Points
IQC	Westgard rules; Levey-Jennings charts; 1₃s/2₂s/R₄s/4₁s/10x̄
EQC	Proficiency testing; Z-score ≤ 2 = acceptable; NABL/ISO 15189
Pleural fluid	Light's criteria; ADA → TB; SAAG not used (use for ascites)
Peritoneal	SAAG ≥ 1.1 = portal HTN (transudate); < 1.1 = exudate
Synovial	Crystal microscopy: MSU (-ve birefringent/yellow) = Gout; CPP (+ve/blue) = Pseudogout
Urine	Casts: RBC cast = glomerulonephritis; WBC cast = pyelonephritis
Semen	Volume ≥ 1.4 mL; Conc ≥ 16 M/mL; Motility ≥ 42%; Morphology ≥ 4%
CSF	WBC < 5; Protein 15-45; Glucose 60-70% serum; xanthochromia = SAH
Autopsy	Clinical = consent, partial possible; ML = police order, always complete
Viscera	Saturated NaCl for preservation; NOT formalin for toxicology
Perinatal	Hydrostatic lung test; karyotype; placental exam

Sources: Henry's Clinical Diagnosis and Management by Laboratory Methods; Tietz Textbook of Laboratory Medicine, 7th Edition; PC Dikshit Textbook of Forensic Medicine and Toxicology; Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology; WHO Laboratory Manual for Examination and Processing of Human Semen.

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