A former top authority on hemophilia was acquitted Wednesday of professional negligence resulting in the death of a male patient through the use of HIV-tainted blood coagulants at Teikyo University Hospital in Tokyo.

The Tokyo District Court ruled that Takeshi Abe, 84, former vice president of the university, could not have clearly anticipated the consequences of using the blood products due to the limited knowledge available on the nature of HIV at the time.

The trial dealt with the death of one patient among dozens of hemophiliacs who were infected with HIV at the hospital. The patient died of AIDS in December 1991 after being infected with HIV through imported blood products administered by Abe's subordinate on three occasions in May and June 1985.