Abnormalities of lymphocyte subsets are correlated with concentrate consumption in asymptomatic Italian hemophiliacs treated with concentrates made from American plasma.

Eighty-three symptom-free hemophiliacs were studied clinically, serologically and by in vitro tests for cellular immunity in a geographical area in which AIDS has not yet been encountered despite the exclusive use of concentrates manufactured from American sources of plasma. Some patients showed the following abnormalities: lymphopenia (4%), decreased T-helper/T-suppressor (Th/Ts) cell ratios (49%), or both abnormalities (2%). Low Th/Ts were mostly due to absolute or, less frequently, relative increases in Ts cells. The prevalence rates for these abnormalities were the same in patients treated with factor VIII or factor IX concentrates. There was an association between the higher Ts and lower Th cells counts and the low Th/Ts ratios and greater annual consumption of factor VIII and factor IX concentrates. These results support the view that protein load might be an important pathogenetic factor in lymphocyte abnormalities in symptom-free hemophiliacs.