A street person well known to the local public health clinic appears to have acute symptoms of hepatitis and tests positive for HDV antigen. Knowing that HDV requires HBV, which of the following sets of test results shows this patient had chronic HBV infection and was superinfected with HDV?

HDV can be acquired as a coinfection-HBV and HDV acquired at the same time; or, as a superinfection-HDV acquired by a person with chronic HBV infection. Diagnosis of HDV infection may be made by detection of delta antigen, anti-HDV IgM and/or IgG, or HDV RNA. Acute, chronic, resolved, or immunized HBV status is determined by a battery of serologic tests. Superinfection with HDV is indicated by positive tests for HDV and the presence of anti-HBcAg IgG but not IgM (b). Coinfection with HDV would be indicated by the presence of anti-HBcAg IgM but not IgG (a).INTERPRETATION OFTHE HEPATITIS B STATUSDisease StateHBsAgHBeAgAnti-HBcAg-IgMAnti-HBcAg IgGAnti-HBsAGAcute (a)+++--Chronic (b)++-+-Resolved (c)---++Vaccinated (d)----+