Give me detailed study material for pathology practical exam for my prefinal..

Urine-15 Peripheral smear-15 Ospi charts-20 Short case-10 Spotters-20 Viva-20

Asking for Preferences

Reading File

Finding Sources

Reading File

Finding Sources

Reading File

Loading Image

Searching the Web

pathology practical exam prefinal MBBS urine analysis peripheral smear OSPI spotters checklist

Reading Web Page

https://www.pathologyoutlines.com/topic/chemistryurinalysis.…

Loading Image

Here is your complete prefinal pathology practical study material covering all six exam components.

PATHOLOGY PRACTICAL EXAM - PREFINAL STUDY MATERIAL

SECTION 1: URINE EXAMINATION (15 Marks)

Step-by-Step Reporting Sequence (follow this order in the exam)

1. Physical Examination 2. Chemical Examination 3. Microscopic Examination

A. Physical Examination

Parameter	Normal	Abnormal + Significance
Volume	1000-1500 mL/24h	Oliguria <400 mL; Anuria <100 mL; Polyuria >2.5 L
Color	Pale to deep amber/yellow	See table below
Appearance	Clear	Turbid = infection, crystals, pus
Smell	Faintly aromatic	Fruity = ketones (DM/starvation); Ammonia = UTI
Specific gravity	1.010-1.025	Low = DI, renal failure; High = dehydration, DM
pH	4.5-8.0 (avg 6.0)	Alkaline urine = UTI, RTA, vegetarian diet
Foam	Minimal white	Persistent frothy = proteinuria (nephrotic syndrome)

Urine Color Chart - HIGH YIELD

Color	Cause
Red/pink	Hematuria, hemoglobinuria, myoglobinuria, rifampicin, beets
Dark yellow/amber	Concentrated urine, urobilinogen excess
Dark brown/cola	Acute glomerulonephritis, myoglobinuria
Yellow-green	Bilirubin (obstructive jaundice)
Milky white	Pyuria (UTI), chyluria (lymphatic obstruction)
Black	Alkaptonuria, melanuria
Orange	Bile pigments, pyridium

B. Chemical Examination (Dipstick)

Parameter	Normal	Positive finding = Suggests
Protein	Negative (trace <15 mg/dL)	Nephrotic syndrome (3-4+), nephritic syndrome (1-2+), UTI, fever
Glucose	Negative	DM (renal threshold exceeded), renal glycosuria (low threshold)
Ketones	Negative	DM ketoacidosis, starvation, alcoholism, prolonged vomiting
Bilirubin	Negative	Conjugated hyperbilirubinemia (hepatic/obstructive jaundice)
Urobilinogen	Trace (0.1-1 EU/dL)	Increased = hemolytic jaundice, hepatic; Absent = obstructive jaundice
Blood (Heme)	Negative	Hematuria (RBCs visible), hemoglobinuria (no RBCs), myoglobinuria
Leukocyte esterase	Negative	UTI (WBCs in urine)
Nitrite	Negative	Gram-negative bacterial UTI (E. coli, Klebsiella)
pH	4.5-8.0	Alkaline = UTI, RTA; Acid = urate stones, gout
Specific gravity	1.005-1.030	Fixed SG 1.010 = isosthenuria (renal tubular failure)

KEY: Bilirubin vs Urobilinogen in jaundice types

Jaundice	Urine Bilirubin	Urine Urobilinogen
Prehepatic (hemolytic)	Negative	Very increased
Hepatic (hepatocellular)	Positive	Increased
Post-hepatic (obstructive)	Strongly positive	Absent/decreased

C. Microscopic Examination

Preparation: Centrifuge at 1500 rpm x 5 min, decant supernatant, resuspend sediment, examine under 10x (low) and 40x (high power).

RBCs

Normal: 0-2 RBCs/HPF
Dysmorphic RBCs (acanthocytes) = glomerular bleeding
Isomorphic RBCs = lower urinary tract bleeding
3 RBCs/HPF = microscopic hematuria

WBCs (Pus cells)

Normal: 0-4 WBCs/HPF
Pyuria: >5 WBCs/HPF
Causes: UTI (most common), pyelonephritis, interstitial nephritis, TB of kidney

Casts - MASTER TABLE (Most important in exam!)

Cast	Composition	Clinical significance
Hyaline cast	Tamm-Horsfall mucoprotein	Normal (in concentrated urine, after exercise); minimal significance
RBC cast	RBCs in protein matrix	Glomerulonephritis - pathognomonic; nephritic syndrome
WBC cast	WBCs in matrix	Pyelonephritis, acute interstitial nephritis
Granular cast	Degenerated cell debris	Non-specific: glomerulonephritis, pyelonephritis, ATN
Waxy cast	Advanced degeneration	End-stage renal disease, chronic renal failure; "broad casts" = severe
Fatty cast	Lipid droplets	Nephrotic syndrome (also oval fat bodies with Maltese cross under polarized light)
Epithelial cast	Renal tubular cells	Acute tubular necrosis (ATN)
Bacterial cast	Bacteria in matrix	Pyelonephritis

Memory tip for casts: "Hyaline-RBC-WBC-Granular-Waxy-Fatty-Epithelial" = Helping Renal Work Gets Wider Faster Eventually

Crystals

Crystal	Appearance	Condition
Uric acid	Yellow-brown rhomboid/barrel	Gout, uric acid stones (acid urine)
Calcium oxalate	"Envelope" or dumbbell shape	Nephrolithiasis, ethylene glycol poisoning
Triple phosphate (struvite)	"Coffin lid" shape	UTI with urease-producing bacteria (Proteus)
Cystine	Hexagonal plates	Cystinuria (autosomal recessive)
Calcium phosphate	Rosette/needle-shaped	Alkaline urine
Ammonium biurate	"Thorny apple"	Alkaline urine, old specimen
Tyrosine	Fine silky needles in clusters	Severe liver disease
Leucine	Yellow-brown oily spheres	Severe liver disease

URINE EXAM - Disease Pattern Recognition

Disease	Key Urine Finding
Nephrotic syndrome	Heavy proteinuria 3.5g+, fatty casts, oval fat bodies, hyaline casts, lipiduria
Nephritic syndrome (AGN)	Hematuria, RBC casts, mild-moderate proteinuria, oliguria
Pyelonephritis	WBC casts, WBCs, bacteria, +leukocyte esterase, +nitrite
ATN	Epithelial casts, granular casts, renal tubular epithelial cells
Chronic renal failure	Waxy/broad casts, isosthenuria (SG fixed ~1.010), proteinuria
DM	Glucosuria, proteinuria (early sign of nephropathy), ketonuria
Rhabdomyolysis	Myoglobinuria (dipstick positive heme but no RBCs in sediment), myoglobin casts
Obstructive jaundice	Bilirubin strongly positive, urobilinogen absent, bile salts positive
UTI (uncomplicated)	Pyuria, +leukocyte esterase, +nitrite, bacteria, cloudy urine

SECTION 2: PERIPHERAL SMEAR (15 Marks)

Step-by-Step Reporting in Exam

Name the stain used - Leishman/Wright/Giemsa/Romanowsky
Describe RBCs - size, color, shape, inclusions
Describe WBCs - perform differential count
Describe platelets - number, morphology
Give a provisional diagnosis

A. RBC Morphology - MASTER TABLE

Abnormal RBC	Description	Key Associations
Microcyte	Small RBC, MCV <80 fL	IDA, Thalassemia, chronic disease (sometimes)
Macrocyte	Large RBC, MCV >100 fL	B12/Folate deficiency, liver disease, MDS
Hypochromia	Increased central pallor (>1/3 diameter)	IDA, thalassemia, sideroblastic anemia
Spherocyte	Small, dense, no central pallor	Hereditary spherocytosis, AIHA
Target cell (codocyte)	Bull's-eye appearance	Thalassemia, HbC disease, liver disease, post-splenectomy
Schistocyte (helmet cell)	Fragmented RBC	MAHA (TTP, HUS), DIC, mechanical heart valve
Sickle cell (drepanocyte)	Elongated crescent/sickle shape	Sickle cell disease (HbSS)
Elliptocyte (ovalocyte)	Oval/elongated RBC	Hereditary elliptocytosis, severe IDA
Acanthocyte (spur cell)	Irregular spicules (5-10), uneven spacing	Abetalipoproteinemia, severe liver disease
Echinocyte (burr cell)	Regular crenations (10-30), even spacing	Uremia, artifact, liver disease
Stomatocyte	Slit-like central pallor ("mouth")	Hereditary stomatocytosis, liver disease, alcohol
Teardrop cell (dacrocyte)	Teardrop/pear shape	Myelofibrosis, thalassemia, megaloblastic anemia
Rouleaux formation	Stack of coins	Multiple myeloma, inflammation (raised ESR)
Agglutination	Irregular clumps	Cold agglutinin disease
Pencil cell	Long thin elliptocyte	Iron deficiency anemia
Bite cell (degmacyte)	Missing "bite" from RBC	G6PD deficiency (Heinz body removal by spleen)

Peripheral smear image - Iron Deficiency Anemia (from Robbins Pathology):

Iron deficiency anemia peripheral blood smear showing hypochromic microcytic RBCs with narrow rim of hemoglobin and pencil cells

Note: Hypochromic microcytic RBCs with enlarged zone of central pallor. Scattered normochromic cells from recent transfusion. - Robbins Pathology

B. Differential Leukocyte Count (DLC) - Normal Values

Cell	Normal %	Normal Absolute
Neutrophils	50-70%	2000-7500/μL
Lymphocytes	20-40%	1500-4000/μL
Monocytes	2-8%	200-800/μL
Eosinophils	1-4%	40-500/μL
Basophils	0-1%	0-100/μL

WBC morphology at a glance:

Cell	Key Feature	Nucleus	Granules
Neutrophil (seg)	"Lobulated"	2-5 lobes connected by filaments	Fine pink-purple, inconspicuous
Band neutrophil	"Immature"	U-shaped, no filament	Same as neutrophil
Lymphocyte (small)	Lymphopenia/lymphocytosis	Round, dark, scant cytoplasm	None (or rare azurophilic)
Monocyte	Largest WBC	Kidney/horse-shoe shaped	Fine azurophilic, vacuoles
Eosinophil	2-lobed	Bilobed (figure-of-8)	Large bright orange-red granules
Basophil	Rarest; nucleus hidden	Bilobed/irregular, hidden by granules	Large dark-blue/black granules

C. Peripheral Smear Patterns - Disease Recognition

Iron Deficiency Anemia (IDA)

Hypochromic microcytic RBCs
Pencil cells (elongated hypochromic cells)
Anisocytosis, poikilocytosis
Target cells (occasionally)
Platelets: often increased (reactive thrombocytosis)

Megaloblastic Anemia (B12/Folate Deficiency)

Macro-ovalocytes (large oval RBCs)
Hypersegmented neutrophils (>5 lobes, or even 1 cell with 6+ lobes = diagnostic)
Anisocytosis, poikilocytosis
Pancytopenia (in severe cases)
Howell-Jolly bodies (sometimes)

Thalassemia

Hypochromic microcytic (MCV lower than IDA for same Hb level)
Target cells (prominent)
Basophilic stippling
Nucleated RBCs (especially in major form)
Tear drop cells

Sickle Cell Disease

Sickle cells (irreversibly sickled)
Target cells
Howell-Jolly bodies (functional asplenia)
Nucleated RBCs

Hereditary Spherocytosis

Spherocytes (no central pallor)
Polychromasia (reticulocytes)
Increased MCHC
Osmotic fragility test positive

Hemolytic Anemia (general)

Polychromasia (reticulocytosis - bluish RBCs)
Nucleated RBCs
Specific cell types depend on cause

Malaria

Ring forms (early trophozoites) inside RBCs - Plasmodium falciparum (multiple rings, appliqué/accole forms)
P. vivax - enlarged RBCs, Schuffner's dots, ameboid trophozoites
P. malariae - band form (ribbon-shaped) trophozoite
P. ovale - oval RBCs, Schuffner's dots

Peripheral smear image - Leukocytes including neutrophils (band and segmented):

Peripheral blood smear showing band neutrophil and segmented neutrophil

D. WBC Abnormalities

Finding	Description	Association
Neutrophilia	>7500/μL	Bacterial infections, stress, steroids, CML
Neutropenia	<1500/μL	Viral infections, aplastic anemia, drugs
Left shift	Increased band forms, metamyelocytes in blood	Severe bacterial infection, CML
Hypersegmentation	Neutrophils >5 lobes	Megaloblastic anemia
Toxic granulation	Coarse dark granules in neutrophils	Severe bacterial infection, sepsis
Dohle bodies	Pale blue cytoplasmic inclusions (neutrophils)	Infections, burns, pregnancy
Auer rods	Pink rod-shaped cytoplasmic inclusions (blasts)	AML (pathognomonic)
Lymphocytosis	>4000/μL	Viral infections, CLL, TB, pertussis
Atypical lymphocytes	Large, irregular, abundant cytoplasm	EBV (infectious mononucleosis), CMV
Blast cells	Large immature cells, prominent nucleoli	Leukemia (AML/ALL)
Smudge cells	Disrupted lymphocytes on smear	CLL (pathognomonic)

SECTION 3: OSPI CHARTS (20 Marks)

OSPI = Objective Structured Practical Interpretation. Charts are usually:

Hematology value charts / CBC interpretation
Liver function test (LFT) charts
Coagulation profile charts
Renal function / urinalysis interpretation charts

A. CBC Chart Interpretation

Normal CBC Values (MEMORIZE)

Parameter	Normal Value
Hemoglobin (M)	13.5-17.5 g/dL
Hemoglobin (F)	12.0-15.5 g/dL
Hematocrit (M)	40-52%
Hematocrit (F)	36-48%
RBC count	4.5-6.5 x 10⁶/μL (M); 3.9-5.5 (F)
WBC count	4000-11000/μL
Platelets	1.5-4.5 x 10⁵/μL
MCV	80-100 fL
MCH	27-33 pg
MCHC	32-36 g/dL
RDW	<14.5%
Reticulocyte count	0.5-2.5%

B. Anemia Classification Chart (OSPI Favourite)

By MCV:

Type	MCV	MCH	MCHC	Common Causes
Microcytic hypochromic	<80 fL	Low	Low	IDA, Thalassemia, Sideroblastic anemia, Anemia of chronic disease
Normocytic normochromic	80-100 fL	Normal	Normal	Acute blood loss, hemolytic anemia, aplastic anemia, ACD
Macrocytic	>100 fL	High	Normal	B12/Folate def, liver disease, hypothyroidism, MDS, drugs (MTX, hydroxyurea)

IDA vs Thalassemia Minor - Chart Differentiation

Feature	IDA	Thalassemia minor
MCV	Low	Very low (disproportionately low)
RBC count	Low	Normal or High
RDW	High (>14.5%)	Normal/slightly raised
Serum iron	Low	Normal
TIBC	High	Normal
Ferritin	Low	Normal/high
HbA2 (HPLC)	Normal	>3.5% (Beta thal minor)
Mentzer Index (MCV/RBC)	>13 = IDA	<13 = Thalassemia

C. Coagulation Profile Chart

Test	Normal Value	Prolonged in
PT (Prothrombin Time)	12-14 sec	Warfarin, Vit K deficiency, liver disease, DIC, Factor VII deficiency (extrinsic pathway)
aPTT (activated PTT)	25-40 sec	Heparin, hemophilia A/B, DIC, lupus anticoagulant (intrinsic pathway)
TT (Thrombin Time)	14-16 sec	Afibrinogenemia, dysfibrinogenemia, heparin excess
INR	~1.0	Elevated in anticoagulation therapy; target 2-3 for DVT treatment
Fibrinogen	200-400 mg/dL	Low in DIC, liver disease, thrombolytic therapy
D-dimer	<0.5 μg/mL	Elevated in DIC, PE, DVT, sepsis
Bleeding time (BT)	1-9 min (Ivy)	Platelet disorders, VWD, aspirin use
Clotting time (CT)	5-11 min	Heparin, coagulation factor deficiencies

DIC Chart Recognition:

Parameter	DIC
PT	Prolonged
aPTT	Prolonged
Platelets	Decreased
Fibrinogen	Decreased
D-dimer	Increased
Peripheral smear	Schistocytes

D. LFT Chart Interpretation

Parameter	Hepatocellular	Cholestatic/Obstructive
AST/ALT	Very high (100-1000s)	Mild elevation
ALP	Mild elevation	Very high
GGT	High	Very high
Bilirubin	Mostly unconjugated (early) / mixed	Mostly conjugated
Albumin	Low in chronic	Normal early
PT	Prolonged	May be prolonged
Urine bilirubin	Positive	Strongly positive
Urine urobilinogen	Increased	Absent

SECTION 4: SHORT CASE (10 Marks)

In a short case, you will be given a clinical scenario + lab reports and asked to:

Identify the diagnosis
Justify with lab findings
Suggest additional investigations
Outline management

Classic Short Cases and Their Approach

Case 1: Anemia workup

Clinical: Fatigue, pallor, pica (clay eating)
Lab: Hb 7 g/dL, MCV 68, MCH 20, MCHC 28, RDW 18%, Serum ferritin 4 ng/mL
Peripheral smear: Hypochromic microcytic RBCs, pencil cells
Diagnosis: Iron Deficiency Anemia
Additional: Serum iron, TIBC, transferrin saturation; find the cause (GI bleed, menorrhagia)
Management: Oral ferrous sulfate 200 mg TID x 3-6 months; treat underlying cause

Case 2: Megaloblastic Anemia

Clinical: Elderly vegetarian, weakness, sore tongue, subacute combined degeneration signs
Lab: Hb 8 g/dL, MCV 115, pancytopenia, hypersegmented neutrophils, macro-ovalocytes
Diagnosis: Megaloblastic anemia (B12 deficiency)
Additional: Serum B12, folate, homocysteine, methylmalonic acid
Management: B12 IM injections (cyanocobalamin 1000 μg); address dietary cause

Case 3: Nephrotic Syndrome

Clinical: Puffiness of face, pedal edema, frothy urine
Lab: Albumin 2.0 g/dL, proteinuria 4+, cholesterol high
Urine: Fatty casts, oval fat bodies, heavy proteinuria >3.5 g/day
Diagnosis: Nephrotic Syndrome
Management: Treat cause (steroids for MCD); diuretics; ACE inhibitors

Case 4: DIC

Clinical: Post-obstetric complication, sepsis, or malignancy; bleeding from multiple sites
Lab: Low platelets, prolonged PT/aPTT, low fibrinogen, high D-dimer, schistocytes on smear
Diagnosis: Disseminated Intravascular Coagulation
Management: Treat underlying cause; FFP, platelet transfusion, cryoprecipitate

Case 5: CML (Chronic Myeloid Leukemia)

Clinical: Splenomegaly, fatigue, weight loss
Lab: WBC very high (50,000-500,000/μL), all stages of granulocyte maturation on smear ("left shift continuum"), eosinophilia + basophilia
Diagnosis: Chronic Myeloid Leukemia
Confirm: BCR-ABL fusion gene (Philadelphia chromosome)
Management: Imatinib (STI-571)

SECTION 5: SPOTTERS (20 Marks)

Spotters are typically gross specimens, histology slides, or instruments. Common categories:

A. Gross Specimens - Common Spotters

Specimen	Key Features to Identify	Diagnosis
Liver - nutmeg liver	Brown-yellow mottled appearance ("nutmeg"), alternating congestion and fatty change	Chronic passive congestion (Right heart failure)
Lung - red hepatization	Solid, heavy, dark red, liver-like consistency	Lobar pneumonia (Day 2-4)
Lung - grey hepatization	Solid, grey, dry cut surface	Lobar pneumonia (Day 4-8)
Kidney - contracted granular	Small, shrunken, granular surface	Chronic glomerulonephritis / hypertensive nephropathy
Kidney - large white	Enlarged, pale, smooth	Nephrotic syndrome (amyloidosis / membranous nephropathy)
Brain - cerebral softening	Pale/yellow soft area	Infarction
Heart - vegetations on mitral	Warty/irregular masses on valve leaflets	Infective endocarditis (large, irregular) or Rheumatic fever (small, along line of closure)
Spleen - lardaceous	Enlarged, pale, waxy, firm	Amyloidosis
Appendix - acute appendicitis	Congested, hyperemic, fibrin-covered serosa	Acute appendicitis

B. Histology Slides - Common Spotters

Slide/Lesion	Key Microscopic Features
Acute inflammation	Vascular dilation, neutrophil infiltration, edema
Chronic inflammation	Lymphocytes, plasma cells, macrophages, fibrosis, giant cells
Granuloma (tuberculosis)	Epithelioid cells, Langerhans giant cells, central caseous necrosis, lymphocytic cuff
Caseous necrosis	Amorphous pink material with ghost outlines (vs coagulative = ghost outline visible; vs liquefactive = none)
Amyloidosis	Homogeneous pink amorphous deposits; Congo red stain = apple-green birefringence under polarized light
Carcinoma in-situ (CIS)	Full-thickness epithelial dysplasia, no basement membrane breach
Invasive carcinoma	Malignant cells breaching basement membrane, desmoplastic stroma
Adenocarcinoma	Glandular formation by malignant cells
Squamous cell carcinoma	Keratin pearls, intercellular bridges
Reed-Sternberg cells	Large binucleate cell, "owl-eye" nucleoli - Hodgkin lymphoma
Psammoma bodies	Laminated calcified concentric spheres - papillary thyroid carcinoma, meningioma, serous cystadenocarcinoma
Foam cells	Lipid-laden macrophages - atherosclerotic plaque (fatty streak)
Hyaline membrane	Eosinophilic membrane lining alveoli - ARDS, RDS of newborn

C. Instruments/Procedures - Spotters

Instrument	Use
Disposable syringe	Blood collection
EDTA tube (lavender/purple top)	CBC, blood smear
Citrate tube (blue top)	Coagulation studies (PT, aPTT)
SST/Serum tube (red/gold)	Serum biochemistry, LFTs
Fluoride-oxalate tube (grey)	Blood glucose (inhibits glycolysis)
Urine dipstick	Urinalysis
Centrifuge	Urine sediment, blood component separation
Bone marrow biopsy needle (Jamshidi)	Bone marrow biopsy
Turk's fluid	WBC counting (dilutes and lyses RBCs)
Hayem's fluid	RBC counting (dilutes RBCs)

SECTION 6: VIVA (20 Marks)

High-frequency viva questions and model answers:

Q1. What is the difference between RBC cast and WBC cast? What is the clinical significance of each?

RBC cast: Red cells within a Tamm-Horsfall protein matrix. Pathognomonic of glomerulonephritis. Indicates glomerular damage with bleeding into the tubule.
WBC cast: White cells in a protein matrix. Indicates pyelonephritis or acute interstitial nephritis - infection/inflammation within the renal parenchyma.

Q2. How do you differentiate IDA from Thalassemia minor on CBC?

Use Mentzer Index: MCV/RBC. >13 = IDA; <13 = Thalassemia
In IDA: RDW high, serum ferritin low, TIBC high
In thalassemia minor: RBC count normal or high, HbA2 >3.5%, ferritin normal

Q3. What are the causes of macrocytic anemia?

Megaloblastic: B12 deficiency, folate deficiency
Non-megaloblastic: Liver disease, hypothyroidism, aplastic anemia, MDS, reticulocytosis, drugs (hydroxyurea, methotrexate, zidovudine, alcohol)

Q4. What is the significance of hypersegmented neutrophil?

Defined as neutrophil with 5 or more lobes, OR any cell with 6+ lobes
Pathognomonic of megaloblastic anemia (B12/Folate deficiency)
Also seen in uremia, iron overload, myelodysplastic syndrome

Q5. What is DIC? How do you diagnose it on lab?

DIC = Disseminated Intravascular Coagulation - widespread activation of the coagulation cascade consuming clotting factors and platelets, paradoxically causing both thrombosis and bleeding
Lab: Low platelets, prolonged PT + aPTT, low fibrinogen, elevated D-dimer, elevated FDPs, schistocytes on peripheral smear

Q6. What is the Congo Red stain used for? What does it show under polarized light?

Used to identify amyloid deposits in tissues
Under normal light: pink-red staining of amyloid
Under polarized light: apple-green birefringence - pathognomonic of amyloid

Q7. Name 5 causes of splenomegaly and how pathology differentiates them.

Infections (malaria, kala-azar, EBV)
Hemolytic anemias (HS, thalassemia)
Congestion (portal hypertension)
Infiltrations (amyloidosis, Gaucher disease)
Neoplasms (CML, lymphoma)

Q8. Differentiate between exudate and transudate.

Feature	Exudate	Transudate
Protein	>3 g/dL	<3 g/dL
Specific gravity	>1.020	<1.015
LDH	High	Low
Cells	Many (neutrophils, lymphocytes)	Few
Cause	Inflammation, infection, malignancy	Heart failure, cirrhosis, hypoproteinemia

Q9. What is a Schiller-Duval body?

Seen in yolk sac tumor (endodermal sinus tumor)
Looks like a glomerulus: central vessel surrounded by tumor cells in a cystic space

Q10. What are the special stains and what they identify?

Stain	Identifies
PAS (Periodic Acid-Schiff)	Glycogen, mucin, fungal cell walls
Congo red	Amyloid (apple-green birefringence)
Ziehl-Neelsen (ZN)	Acid-fast bacilli (Mycobacterium TB)
Prussian blue (Perl's)	Hemosiderin/iron deposits
Oil red O	Lipids/fat (requires fresh frozen sections)
Reticulin (Silver)	Reticular fibers (hepatic architecture, myelofibrosis)
Masson's trichrome	Collagen (blue/green), muscle (red)
Mucicarmine	Mucin (cryptococcus capsule)
Toluidine blue	Mast cells (metachromatic)
Alcian blue	Acid mucopolysaccharides

Q11. What is the difference between necrosis and apoptosis?

Feature	Necrosis	Apoptosis
Type	Pathological	Physiological/Pathological
Cells affected	Groups of cells	Single cells
Membrane	Disrupted	Intact
Inflammation	Yes (prominent)	No
ATP required	No	Yes
DNA	Random fragments	Ladder pattern (180 bp multiples)
Phagocytosis	Neutrophils first	Macrophages

EXAM DAY TIPS

Urine exam: Always report in the sequence - Physical → Chemical → Microscopic. State "normal" for each if negative.
Peripheral smear: Identify the predominant RBC abnormality first, then name it, then give 2-3 causes.
OSPI charts: Read all values before giving a diagnosis. Compare values with normals.
Short case: Use a systematic approach - history clue → lab → diagnosis → management.
Spotters: State the specimen type, organ, gross appearance, then give the diagnosis with one key feature justification.
Viva: Speak confidently. If unsure, mention what you know and what you would investigate.

Sources: Henry's Clinical Diagnosis and Management by Laboratory Methods; Robbins & Cotran Pathologic Basis of Disease; ROSEN's Emergency Medicine; Tietz Textbook of Laboratory Medicine; Pathology Outlines - Urinalysis

This is a shared conversation. Sign in to Orris to start your own chat.