J Bouhasin, MD, St. Louis, Missouri. Div of Blood and Blood Products, Center for Biologics Evaluation and Research, Food and Drug Administration. Seroconversion data provided to CDC come from a combination of prospective surveillance, ongoing cohort studies, and anecdotal reports. The proportion of products treated according to more rigorous procedures was higher for these 1,489 patients than the proportion typically received by U.S. and Canadian patients during the same period. The potential for the newer types of factor concentrates to transmit hepatitis viruses is still being studied.
Anecdotal cases are often more difficult to evaluate than prospectively studied patients.
Compared with older processes, most of the newer processes produce fewer units of factor activity per unit of source plasma collected. Pending procedural improvements, this less efficient recovery of clotting factor reduces the supply of available concentrates. After reviewing the data presented at the CDC-sponsored meeting, the Medical and Scientific Advisory Committee of the NHF established and published recommendations for U.S. physicians treating hemophilia patients. The risks of withholding factor treatment far outweigh the risks of treatment, but health-care providers should educate patients to use appropriate doses of clotting factor to minimize overuse and to contain costs. When feasible, an alternative to concentrates may be the use of cryoprecipitate prepared from one well-screened and repeatedly tested donor or from a small number of such donors.