Altered immunity in haemophiliacs treated exclusively with cryoprecipitate.

Sixty-five patients with haemophilia A from Singapore General Hospital, treated within the last 15 years exclusively with cryoprecipitate, were studied for the effect of the total number of exposures to random blood donors on their immune system. These haemophiliacs were aged 4 to 71 years (median 24 years) and were all apparently healthy with no clinical evidence of viral infection. None of them was a homosexual or intravenous drug user. All of them tested negative for human immuno-deficiency virus antibody and hepatitis B surface antigen. Analysis of the T-lymphocyte subset population showed 20 out of 65 haemophiliacs or 30.8% had reversal of T4/T8 ratio, ie. less than 1.00. There was no significant difference in the mean age of the 20 patients with abnormal T4/T8 ratios compared with the 45 with normal T4/T8 ratios. The mean age of the former group was 23 and the latter was 25. The group with reversal of T4/T8 ratio had exposure to 827.4 +/- 137.3 (mean +/- SEM) random blood donors, which is significantly higher than 402.5 +/- 64.1 in the group with normal T4/T8 ratio (p < 0.05). The reversal of T4/T8 ratio is predominantly due to the suppression of absolute T4 cell counts, with slightly raised absolute T8 cell counts. This abnormality may be transient or permanent. Interestingly, all the six out of 65 haemophiliacs with factor VIII inhibitor did not show any reversal of T4/T8 ratio in this study.