Prophylaxis with factor concentrates in preventing hemophilic arthropathy.

Seven children with severe hemophilia A on prophylactic substitution therapy since a mean age of 5 years (group I) were investigated in 1978 (at ages 6-12 years) and in 1988 (at ages 16-22 years). The results were compared with those of seven children aged 5-12 for whom such treatment was started at a mean age of 3 years (group II). In group I, four had each had more than 20 ankle hemarthroses at the first investigation, while in group II, only one boy had experienced such a high bleeding frequency. Radiological changes in ankles were found in one of seven in group II compared with five of seven in group I. Progression of these changes was shown in eight of 10 ankles of group I at reinvestigation. Regular prophylactic therapy must start early, at ages 1-2 years, to prevent changes in ankle joints, and parents and children must learn to recognize ankle bleeding. Modern Factor VIII concentrates must be administered to children two or three times per week in dosages of 3,000 U/kg/year in order to reduce hemarthroses to a minimum. The dosages can probably be lowered if the intervals are shortened. Children on prophylactic treatment can engage in regular sports activities.