Hepatitis D diagnostics:Utilization and testing in the United States.

Hepatitis D virus (HDV) infection may accompany acute or chronic hepatitis B virus infection. While HDV infection in the United States is thought to be uncommon, there are limited data regarding frequency of testing, and prevalence of HDV antibody and HDV RNA. We evaluated the use of HDV antibody testing using electronic medical record (EMR) data. Among 1007 HBsAg positive patients, only 121 had been tested for HDV antibody. Testing was performed primarily by gastroenterologists/hepatologists and limited testing was performed in identifiable high risk groups including those with HBV/HIV coinfection. Overall, HDV antibody was detected in 3.3% (95% C.I. = 0.9%-8.2%) An HDV RNA assay was developed and validated and 138 HBV or HBV/HIV coinfected patients were tested. The prevalence of HDV among the HBV/HIV coinfected subjects was 2.2% (95% C.I. = 0-5.3%). In a U.S. Midwestern population of HBV infected patients, HDV testing is under-employed. Overall prevalence exceeds 2% whether testing by antibody or HDV RNA and more comprehensive HDV surveillance may be indicated.