SAN FRANCISCO — Acute hepatitis C infections among individuals who are HIV positive have been documented in four countries, and treatment of this coinfection remains controversial, Dr. Marion G. Peters said at a meeting on HIV management sponsored by the University of California, San Francisco.
The largest outbreak was documented in the United Kingdom, where 210 individuals from London and surrounding cities were found to be infected. Cases also have been reported in Germany, France, and the United States.
Dr. Peters of the University of California, San Francisco, and her colleagues documented 11 cases of acute HCV infection in the San Francisco Bay Area among men who have sex with men. Presentations varied greatly, ranging from incidental elevations of aspartate aminotransferase and alanine aminotransferase levels to severe liver dysfunction.
Ten of the 11 patients had adequate CD4 counts. Five patients were treated with interferon and ribavirin, and four of them achieved sustained virologic responses. Six patients were untreated; three of them developed chronic hepatitis C and three seroconverted spontaneously, losing their hepatitis C RNA.
Among the 210 patients with acute hepatitis C documented in London, 64% were on antiretroviral therapy, and their mean CD4 count was 552 cells/mm3, which Dr. Peters described as “perfectly adequate.”
Subtyping identified five clusters of patients. The patients in each of the clusters apparently acquired the virus from a single individual or small set of individuals. One of the clusters contained 43 patients. Genotype 1a was found in 78% of the cases overall.
A case-control study involving 60 of the 210 patients documented significant levels of high-risk behavior. Patients with acute hepatitis C were more likely than were controls to be users of intravenous drugs, and they reported a larger median number of sexual partners.
Studies of monogamous couples in which both partners have hepatitis C show that their viruses are rarely identical, and that sexual transmission occurs in only 1 case in 500. This suggests that blood-to-blood transmission, perhaps due to traumatic sexual practices, is likely to account for the transmission of hepatitis C in patients who are HIV positive.
Most authorities recommend treating these coinfected patients with interferon and ribavirin, but controversy remains over when to begin that treatment. Many patients seroconvert on their own, so the question is how long to wait.
“There's a big argument in the world literature [over] whether you should wait 12 weeks, 24 weeks, [or some other length of time],” Dr. Peters said. “We know that if you wait too long the patient will become chronic and then [his or her] chances of responding are very low. So we are fairly aggressive, and if we have a pinpoint of when they acquired [the infection], I would wait 12 weeks. If we don't have a pinpoint, it's doctor-patient preference.”