To the Editor.
—We were interested to read the excellent report by Perrillo et al1 in the January 1984 issue of the Archives. We were surprised at their low failure rate and have reviewed our records for 1982 and 1983 on hepatitis B surface antigen (HBsAg)—negative consorts of cases of acute hepatitis B.The treatment was a single dose of approximately 500 IU of hepatitis B immunoglobulin (HBIg) (equivalent of 2.8 mL of the standard used in the United States), which was given as soon as possible after an initial specimen had been found to be negative for HBsAg. The initial specimen and specimens taken one month and six months later were tested for HBsAg, antibody to HBsAg (anti-HBs), and antibody to hepatitis B core antigen (anti-HBc). Our initial specimen was found to have hepatitis B markers and was excluded from our study. There were ten patients who had