Back HCV Prevention Acute HIV-HCV Coinfection Increasingly Common in U.K.; HCV Superinfection Reported in France

Acute HIV-HCV Coinfection Increasingly Common in U.K.; HCV Superinfection Reported in France

Several outbreaks of apparently sexually transmitted acute hepatitis C virus (HCV) infection have been reported in recent years in large cities in the U.K. and Europe, primarily among HIV positive men who have sex with men (MSM)Two new reports on sexually transmitted HCV in HIV positive men were published in the March 12, 2008 issue of AIDS.

Increasing Acute Coinfection Incidence in the U.K.

As described in the first report, researchers in the U.K. looked at the incidence of acute or primary HIV infection coinciding with acute hepatitis C.

As background, the authors noted that U.K. guidelines recommend hepatitis C antibody screening at the time of HIV diagnosis and subsequently according to risk, but that risk is not well defined. This approach, they wrote, "may delay the diagnosis of incident [HCV] infection, permitting unknowing transmission and missed opportunities for early intervention."

Since primary HIV infection is associated with high-risk sexual behavior and a high frequency of concurrent sexually transmitted infections (STIs), the researchers hypothesized that individuals diagnosed with acute HIV may be particularly vulnerable to HCV acquisition.

They recruited 155 HIV positive MSM with primary HIV infection at St. Mary's Hospital in London between 1999 and 2006. Sexual behavior histories, ALT measurements, and HCV blood tests were performed at 3-month intervals. Retrospective HCV RNA polymerase chain reaction (PCR) testing was done using stored serum sample to determine the approximate time of HCV infection.

Results

A total of 11 out of 155 men (7%) experienced HCV seroconversion within the study period.

By year, the rates of HCV acquisition among MSM with acute HIV were as follows:

0 out of 20 cases in 1999;
0 out of 40 in 2000;
0 out of 65 in 2001;
0 out of 72 in 2002;
0 out of 90 in 2003;
1 out of 40 (2.5%) in 2004;
4 out of 130 (3.1%) in 2005;
6 out of 155 (3.9%) in 2006.

 

The median time from diagnosis of primary HIV infection to anti-HCV antibody detection was 23 months (range 8-42 months).

3 HCV seroconversions occurred during the first year after primary HIV infection, 4 during the second year, 2 during the third year, 1 during the fourth year, and 1 during the fifth year.

9 out of 11 individuals were identified with acute HCV after experiencing symptoms or having elevated ALT.

2 individuals with reported high-risk sexual behavior but normal ALT were identified by HCV serology.

Testing of retrospective samples showed that all individuals were HCV RNA negative at the time of primary HIV infection.

HCV RNA was detected before anti-HCV antibody detection in 4 cases.

8 men had HCV genotype 1a and 2 had genotype 4d.

7 of the 11 had an increase in HIV viral load at the time of HCV seroconversion.

6 of the 11 men with acute HCV acquired another STI after primary HIV infection, which was significantly higher than the rate for the primary HIV cohort as a whole (26 out of 155).

In the 3 months preceding HCV seroconversion, all the recently infected individuals denied injection drug use, 10 had used recreational drugs, 8 reported fisting, and 4 reported sharing sex toys with casual partners.

2 of the 11 acutely infected individuals cleared HCV spontaneously, while 9 developed chronic infection.

"We show that individuals with primary HIV infection have higher rates of HCV acquisition than other HIV positive cohorts, that HCV acquisition can occur soon after acquiring HIV, and that the incidence of HCV infection is increasing," the authors wrote.

"The higher incidence of STI acquisition in those acquiring HCV highlights the importance of safe sex counseling in HIV positive individuals," they added. "Unprotected sexual contact has grave implications for both the ongoing HIV and the emerging HCV epidemics in MSM. This emphasizes the need for prevention efforts and HCV education among HIV-infected individuals, particularly those reporting high-risk sexual behavior and recreational drug use."

Finally, they concluded, "This study supports the enhanced surveillance of high-risk groups to identify new HCV cases to prevent the onward transmission of both HCV and HIV and to allow the opportunity for early treatment intervention to enhance HCV clearance rates."

Sexually Transmitted HCV Superinfection in France

In a related report, French researchers described 2 cases of apparently sexually transmitted HCV superinfection in HIV-HCV coinfected patients with high-risk sexual behavior.

Both individuals had chronic HCV infection and a history of syphilis. HCV superinfection was confirmed by phylogenetic analysis. The first patient was diagnosed with HCV genotype 4a in 2002, and was found to also have genotype 3 the following year. The second man was diagnosed with genotype 1a in 2004, received anti-HCV treatment and achieved undetectable HCV RNA, but 6 months later tested positive for a genetically distinct genotype 1a strain, suggesting superinfection rather than late relapse.

For both men, no risk factors for HCV infection were identified other than unprotected anal sex with multiple male partners. Neither patient spontaneously cleared HCV.

Based on these findings, the authors wrote, "Although the importance of sexually transmitted HCV superinfection remains limited in the general population, HCV-HIV coinfected MSM with high-risk mucosal traumatic sexual practices should be aware of sexually transmitted HCV superinfection and should also benefit from education-based public health interventions."

In addition, they recommended that, "HCV serology and serum HCV RNA should be examined periodically in HIV-infected MSM who continue to engage in high-risk sexual behaviors."

3/18/08

References

J Fox, E Nastouli, E Thomson, and others. Increasing incidence of acute hepatitis C in individuals diagnosed with primary HIV in the United Kingdom. AIDS 22(5): 666-668. March 12, 2008.

J Ghosn, V Thibault, C Delaugerre, and others. Sexually transmitted hepatitis C virus superinfection in HIV/hepatitis C virus co-infected men who have sex with men. AIDS 22(5): 658-661. March 12, 2008.