Page 307 - Concise Pathology for Exam Preparation ( PDFDrive )

292 SECTION II Diseases of Organ Systems

• Percentage of total iron-binding protein to which iron is attached is called percentage
saturation. Normal percentage saturation is 33%.
Serum Fe
%age saturation =
TIBC

Iron Studies
• Serum iron levels in a normal adult are 0.7–1.8 mg/L.
• Normal TIBC (total iron-binding capacity) is 2.5–4.0 mg/L.
• Normal ferritin levels are 20–300 mcg/L in males and 15–150 mcg/L in females.
• Ferritin levels are raised in acute leukaemias, inflammation and Hodgkin disease.
• Ferritin levels are decreased in liver disease.

Iron Excretion
Normal average excretion of iron in urine, faeces and sweat per day is about 0.5–1 mg.
Another 0.5–1.0 mg is lost in menses.

Q. Outline the aetiopathogenesis, clinical features and blood picture
of iron-deficiency anaemia (IDA).
Ans. IDA is the most common type of anaemia met with in clinical practice.

Causes
• Pathological blood loss: Peptic ulcer, haemorrhoids, hiatus hernia, carcinoma stomach and
colon, chronic aspirin ingestion, oesophageal varices, ulcerative colitis, hookworm infesta-
tion, haematuria, repeated epistaxis, haemoptysis and pathological uterine bleeding.
• Increased physiological demand: Growing children and women in reproductive age group
• Inadequate intake
• Nutritional deficiency: Poverty, dietary fads, anorexia and poor bioavailability of
nonhaem iron.
• Impaired absorption: Gastroenterostomy, tropical sprue, celiac disease, atransferri-
naemia, abnormal transferring function or antibodies to transferring receptors.
• Plummer–Vinson (Paterson–Kelly) syndrome: Syndrome complex of chronic iron
deficiency, dysphagia due to postcricoid web and glossitis

Stages of Iron Deficiency
1. Storage iron depletion
2. Iron-deficient erythropoiesis
3. Frank iron-deficiency anaemia

Decreased iron stores

Decreased serum iron, TIBC, percentage saturation

Normocytic followed by microcytic anaemia

Clinical Features

Signs and symptoms are due to:
• Anaemia: Lassitude, weakness, fatigue, dyspnoea, palpitations, angina, CCF and pallor
• Epithelial tissue changes:
• Nails: Thin, lusterless, brittle, show ridging and flattening; presence of koilonychia
(spoon-shaped nails)
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