Effect of hydroxyurea on foetal haemoglobin in myeloproliferative & myelodysplastic syndromes.

The effect of hydroxyurea on foetal haemoglobin (HbF) levels was evaluated in 36 patients of myeloproliferative and myelodysplastic disorders. In 17 (47.2%) patients, HbF levels increased from 1.40 +/- 1.17 to 3.03 +/- 1.97 per cent after 4 wk therapy with hydroxyurea. In the responders this increase was highly significant (P less than 0.001). The rise in the HbF levels after hydroxyurea therapy was significant in patients with chronic myeloid leukaemia but not in the other groups.