Homozygous sickle cell disease and priapism in the eastern province of Saudi Arabia.

Two adult sickle cell homozygotes from the eastern oases of the Kingdom of Saudi Arabia presented with severe persistent priapism. Each patient had a high Hb F of 24%, and their red cells were neither hypochromic nor microcytic. Priapism probably occurs more frequently in homozygous sickle cell disease than reported previously from this region. It would appear that a high fetal haemoglobin alone without hypochromia and microcytosis--features suggestive of co-existing alpha-thalassaemia--does not protect against this agonizing vaso-occlusive event.