1. Anemia

↓ Hemoglobin → Pallor

Based on MCV

MCV Value	Type	Examples
< 80 fL	Microcytic	Iron deficiency, Anemia of chronic disease, Sideroblastic, Thalassemia
80–100 fL	Normocytic	Acute blood loss, Hemolytic anemia, Aplastic anemia, ACD (early)
> 100 fL	Macrocytic	B12 deficiency, Folate deficiency, Alcoholism, Liver disease, Drugs (MTX)

Hemoglobin Structure & Related Anemia

Component	Normal	Related Anemia
Heme	Iron + Protoporphyrin	Iron deficiency, ACD, Sideroblastic
Globin chains	2α + 2β	Thalassemia (α or β defect)

2. Iron Deficiency Anemia

Causes: Hookworm, ↓ intake, chronic bleeding

Clinical: Pallor, SOB, fatigue

Adults → Koilonychia, ↓ Iron, ↓ Ferritin, ↑ TIBC
Children → Pica

Special:

Plummer-Vinson: Iron deficiency + Dysphagia + Esophageal web
Sideroblastic: Alcohol, INH, Lead; Iron trapped → Ring sideroblasts

Treatment:

Pyridoxine (for INH-induced)

Treat cause

Iron supplementation

3. Thalassemia (Globin Gene Defects)

Feature	Alpha	Beta
Genes	4 α (Chr 16)	2 β (Chr 11)
1 deletion	Silent carrier	Minor (1 mutated)
2 deletions	Trait (mild)	Major (2 mutated)
3 deletions	HbH disease (β4)	–
4 deletions	Hb Bart’s → Hydrops fetalis	–
Key Hb	HbH, Hb Bart’s	↑ HbF, ↑ HbA2

Complications of β-thal major:

Aplastic crisis (Parvovirus B19)
Secondary hemochromatosis (transfusions)

4. Normocytic Anemias

G6PD Deficiency → Infection/fava/drugs → Heinz bodies, bite cells → avoid triggers

Sickle Cell → HbS → vaso-occlusion, dactylitis, acute chest → Hydroxyurea

PNH → Complement defect → night hemolysis, thrombosis → supportive/transplant

5. Megaloblastic Anemia

Clinical: Pallor, glossitis, mild jaundice

Neuro: Only in B12 (paresthesia, ataxia, memory loss)

Biochemistry:

B12 → ↑ Homocysteine, ↑ MMA
Folate → ↑ Homocysteine only

Absorption sites: Iron → duodenum; Folate → jejunum; B12 → ileum (IF dependent)

Smear: Macro-ovalocytes, hypersegmented neutrophils

Causes:

B12: Pernicious anemia, gastrectomy, Crohn’s, tapeworm, vegans, metformin, PPIs
Folate: Alcoholics, elderly, pregnancy, celiac, MTX, phenytoin, TMP

Treatment:

B12 → IM injection
Folate → oral folic acid

6. Leukemia

Blast → Acute (ALL, AML)
Cytic → Chronic (CML, CLL)

Age:

0–20 → ALL
21–50 → AML
51–60 → CML
60 → CLL

7. Multiple Myeloma / MGUS

MGUS <30% plasma cells
Plasma cell cancer >50 yrs

CRAB: ↑Ca, Renal, Anemia, Bone pain
Dx: BM biopsy, Bence-Jones proteins

8. Lymphomas

Feature	Hodgkin	Non-Hodgkin
Spread	Localized, contiguous	Generalized, extranodal
Prognosis	Nodular sclerosis, LP → good; LD → poor	Follicular, Mantle, Burkitt (t[8;14], c-myc, EBV)
Pattern	Stepwise	Non-contiguous
Age	Young adults	Older adults

Translocations:

t(14;18) → Follicular
t(15;17) → APL
t(9;22) → CML (Philadelphia)
t(8;14) → Burkitt
t(11;14) → Mantle

9. Coagulation Disorders

Platelet count: Normal 1.5–4 lakh/µL

↓ → Thrombocytopenia → mucosal bleeding
↑ → Thrombocytosis

Quantitative Disorders

ITP: Autoantibodies, post-infection/vaccine → ↓ Platelets → Tx: Steroids, IVIG, splenectomy
TTP: ↓ ADAMTS13 → ↑ vWF multimers → microthrombi
- Pentad: Renal failure, Fever, Neuro, Anemia, Thrombocytopenia
- Tx: Plasma exchange