Splenic function in haemophilia.

Studies of splenic function were carried out on 17 haemophilic patients over 9 years of age, and 20 control patients. The clearance of autologous heat-damaged 99mTc-labelled erythrocytes from circulation and into the spleen was measured: the spleen area by scintillation scanning, and the enumeration of pitted erythrocytes by direct interference microscopy. Splenic enlargement was observed in 10 patients (59%). On the basis of the clearance half-time, splenic function was normal in 3/13 (23%) and hyperactive in 9/13 (69%) patients. One heavily transfused patient had a hypoactive spleen with long clearance half-time, slow splenic uptake of radioactivity and high pit counts. These results demonstrate that the spleen of haemophiliacs is usually enlarged and functionally abnormal.