Bone marrow in iron deficiency

Additional tests for differential diagnostics in IDA

•Reticulocytes

•Hemosiderinuria

•Hemoglobinuria

•Hb electrophoresis

•HbA2 level

•Search for the possible sources of chronic blood loss and malabsorbtion

Management of IDA

Megaloblastic anemia

•Megaloblastosis describes a heterogeneous group of disorders that share common morphologic characteristics: large cells with an arrest in nuclear maturation.

•Cause: impaired DNA synthesis and, to a lesser extent, RNA and protein synthesis.

–B12 deficiency

–Folate deficiency

•Most apparent in rapidly dividing cells such as blood cells and gastrointestinal cells.

Daily need in B12 and folic acid

B12

•Need: 5-7 μg

•In storage: 3 mg

•Symptoms develop within 3-5 years after gastrectomy Folic acid

•Need: 400 μg

•In storage: 1-2 mg

•Symptoms develop within 3-4 weeks after folate intake is stopped

Vitamin B12 absorption and transport.

Classification Of The Megaloblastic Anemias

COBALAMIN DEFICIENCY

I. Inadequate intake: vegetarians (rare)

II.Malabsorption

A.Inadequate production of intrinsic factor (IF)

1.Pernicious anemia

2.Gastrectomy

3.Congenital absence or functional abnormality of IF (rare)

B.Disorders of terminal ileum

1.Tropical sprue

2.Nontropical sprue

3.Regional enteritis

4.Intestinal resection

5.Neoplasms and granulomatous disorders (rare)

6.Selective cobalamin malabsorption (Imerslund's syndrome) (rare)

C.Competition for cobalamin

1.Fish tapeworm

2.Bacteria: "blind loop" syndrome

D.Drugs: p-aminosalicylic acid, colchicine, neomycin

III.Other

A.Nitrous oxide

B.Transcobalamin II deficiency (rare)

Classification Of The Megaloblastic Anemias

FOLIC ACID DEFICIENCY

I.Inadequate intake: unbalanced diet (common in alcoholics, teenagers, some infants)

II.Increased requirements

A.Pregnancy

B.Infancy

C.Malignancy

D.Increased hematopoiesis (chronic hemolytic anemias)

E.Chronic exfoliative skin disorders

F.Hemodialysis

III.Malabsorption

A.Tropical sprue

B.Nontropical sprue

C.Drugs: Phenytoin, barbiturates, (?) ethanol IV. Impaired metabolism

A.Inhibitors of dihydrofolate reductase: methotrexate, pyrimethamine, triamterene, pentamidine, trimethoprim

B.Alcohol

C.Rare enzyme deficiencies: dihydrofolate reductase, others