Hematology – Anemias & Porphyrias (First Aid 2025 High-Yield) – VOCABULARY Flashcards

Vocabulary flashcards covering key concepts from the notes on microcytic, normocytic, macrocytic anemias and porphyrias.

Iron Deficiency Anemia

Microcytic, hypochromic anemia due to iron deficiency from chronic blood loss, malnutrition, or malabsorption; features include ↑RDW, koilonychia (spoon nails), and pica.

Anemia of Chronic Disease

Anemia from inflammation causing increased hepcidin and iron sequestration; labs show normal/high ferritin, ↓ serum iron, ↓ TIBC; seen in chronic infections, cancer, CKD, autoimmune disease.

β-thalassemia major

Severe reduction/absent β-globin synthesis causing transfusion-dependent microcytic anemia; ↑HbF.

α-thalassemia

Decreased α-globin synthesis with clinically variable severity; cis deletion common in Asians, trans deletions common in Africans.

Sideroblastic Anemia

Defect in protoporphyrin synthesis causing iron to accumulate in mitochondria; ring sideroblasts in marrow, basophilic stippling; ↑iron and ↑ferritin; caused by ALAS defect, alcohol, lead, isoniazid, B6 deficiency.

Lead Poisoning

Lead inhibits ferrochelatase and ALA dehydratase, reducing heme synthesis; microcytic anemia with basophilic stippling, Burton lines; wrist/foot drop; abdominal colic; encephalopathy in kids.

Hemolytic Anemia (Intrinsic)

Hemolysis due to intrinsic RBC defects such as membrane defects (e.g., hereditary spherocytosis), enzyme deficiencies (G6PD, PK), HbC, or sickle cell disease.

Hemolytic Anemia (Extrinsic)

Hemolysis due to external factors such as autoimmune antibodies (IgG or IgM), microangiopathic processes (DIC, TTP/HUS), or mechanical destruction (prosthetic valves); often Coombs positive.

Hereditary Spherocytosis

Defect in RBC membrane proteins (spectrin/ankyrin) causing spherical RBCs with splenic sequestration; ↑MCHC; splenomegaly; aplastic crisis with Parvovirus B19; diagnosed by osmotic fragility test and EMA binding.

Sickle Cell Disease

β6 Glu→Val mutation in β-globin leading to HbS polymerization in low O2; vaso-occlusive crises and dactylitis; autosplenectomy with Howell-Jolly bodies; risks include acute chest syndrome, stroke, priapism.

G6PD Deficiency

X-linked enzyme defect reducing NADPH; oxidative stress (fava beans, sulfa drugs, antimalarials) triggers hemolysis; Heinz bodies and bite cells on smear.

Autoimmune Hemolytic Anemia

Hemolysis due to autoantibodies: warm IgG (e.g., SLE, CLL) or cold IgM (e.g., Mycoplasma, EBV); Coombs test positive.

Megaloblastic Anemia – B12 Deficiency

Impaired DNA synthesis due to B12 deficiency; hypersegmented neutrophils; ↑ homocysteine and ↑ methylmalonic acid; neurologic symptoms (subacute combined degeneration); causes include pernicious anemia, vegan diet, Crohn’s disease, Diphyllobothrium.

Megaloblastic Anemia – Folate Deficiency

Impaired DNA synthesis due to folate deficiency; hypersegmented neutrophils; ↑ homocysteine; normal methylmalonic acid; no neurologic symptoms; causes include alcoholism, pregnancy, methotrexate, trimethoprim, phenytoin.

Orotic Aciduria

UMP synthase deficiency causing impaired pyrimidine synthesis; megaloblastic anemia refractory to B12/folate; orotic acid in urine; no hyperammonemia; treatment with uridine monophosphate (UMP).

Non-megaloblastic Macrocytic Anemia

Macrocytosis without hypersegmented neutrophils; common causes include liver disease, alcoholism, reticulocytosis.

Acute Intermittent Porphyria

Porphobilinogen deaminase deficiency; 5 Ps: Painful abdomen, Port-wine urine, Polyneuropathy, Psychological disturbances; precipitated by CYP-inducing drugs; treated with hemin and glucose.

Porphyria Cutanea Tarda

Uroporphyrinogen decarboxylase deficiency; blistering cutaneous photosensitivity, tea-colored urine; most common porphyria; associated with hepatitis C and alcoholism; treated with phlebotomy and trigger avoidance.