Frequency and significance of delta antibody in acute and chronic hepatitis B. A United States experience.

Of 560 hepatitis B surface antigen-positive patients who were tested for antibody to hepatitis delta-antigen by blocking radioimmunoassay, 29 (5%) were seropositive. Patients with chronic active hepatitis had a greater frequency of seropositivity than those with chronic persistent hepatitis (26% vs. 0%, p less than 0.05), and patients with symptomatic chronic disease harbored the antibody more commonly than asymptomatic counterparts (14% vs. 2%, p less than 0.01) or patients with acute hepatitis (14% vs. 1%, p less than 0.02). Of 8 patients with acute fulminant hepatitis, including 6 who died of liver failure, none were seropositive. Antibody was detected in drug users, dialysis patients, hemophiliacs, and transfusion recipients; in 17 patients, however, including 3 homosexuals, it occurred sporadically. Samples harvested in 1969 contained delta-antibody. Antibody was found in most ethnic groups, including Orientals, where it occurred only in relocated Vietnamese. We conclude that delta-antibody is detected infrequently in a diverse referral population within the United States. Seropositivity is associated with symptomatic chronic disease and histologic findings of chronic active hepatitis. Homosexuals and resettled Vietnamese are susceptible to sporadic delta-infection.