Aetiologies of Haemochromatosis

Haemochromatosis refers to iron overload, which may be primary (hereditary) or secondary, arising from conditions that cause chronic transfusion requirement, ineffective erythropoiesis, or excess iron absorption. The correct answer is 1, 2 and 4 — Thalassaemia, Anaemia of pyruvate kinase deficiency, and Porphyria cutanea tarda.

Analysis of Each Option

• 1. Thalassaemia — Correct. Thalassaemia causes both ineffective erythropoiesis (which upregulates intestinal iron absorption) and requires repeated blood transfusions, both of which lead to secondary iron overload/haemochromatosis.
• 2. Anaemia of pyruvate kinase deficiency — Correct. This is a chronic haemolytic anaemia. Chronic haemolysis with ineffective erythropoiesis suppresses hepcidin, increasing intestinal iron absorption, and repeated transfusions add further iron load — a recognised cause of secondary haemochromatosis.
• 3. Chronic cor pulmonale — Incorrect. This is right heart enlargement secondary to chronic lung disease/pulmonary hypertension. It has no established mechanism of iron overload and is not a recognised cause of haemochromatosis.
• 4. Porphyria cutanea tarda (PCT) — Correct. PCT is closely and bidirectionally linked with hepatic iron overload — mild-to-moderate iron loading inhibits hepatic uroporphyrinogen decarboxylase activity, precipitating the disease, and PCT is a well-recognised secondary/associated cause of haemochromatosis in standard references; phlebotomy (iron reduction) is a mainstay of treatment, underscoring the iron-overload link.

Conclusion

The correct combination of aetiologies is Thalassaemia, Anaemia of pyruvate kinase deficiency, and Porphyria cutanea tarda (1, 2 and 4), while Chronic cor pulmonale (3) is not a recognised cause of iron overload.