Thalassaemia

Question 1

Types & symptoms

Answer 1

The heterozygous form is usually asymptomatic

• patients show little if any anaemia.

The homozygous form is a very severe congenital anaemia

• needing lifelong transfusional support to keep Hb >90 g/L plus iron chelators.

Question 2

The key to the diagnosis of the heterozygous

Answer 2

Heterozygous ‘thalassaemia minor’ is significant microcytosis quite out of proportion to the normal Hb or slight anaemia,

Confirmed by;

• finding a raised HbA2 on Hb electrophoresis

or by

• DNA analysis.

It must be distinguished from iron-deficiency anaemia, for iron does not help thalassaemics and is theoretically contraindicated.