People with both hepatitis B virus (HBV) and hepatitis C virus (HCV) co-infection
may experience more rapid and severe liver disease progression than those with
hepatitis B alone, though HBV/HCV co-infection did not appear to worsen
hepatitis C progression, according to a French study presented at the European
Association for the Study of the Liver (EASL) 50th International Liver Congress in April in Vienna, Austria.
Due to overlapping transmission routes, many people are co-infected with
both HBV and HCV. Previous research has shown that HBV and HCV appear to
compete with each other in the body, with one virus typically becoming
dominant. Studies indicate that co-infection with both viruses may lead to more
severe liver disease, but research has been limited for non-Asian patients
(Asia and Africa have the highest prevalence of hepatitis B worldwide).
Stanislas Pol from Université René
Descartes in Paris, France, and colleagues analysed characteristics and
outcomes among people with HBV and HCV co-infection in the ANRS CO22 HEPATHER
cohort, comparing them to participants with either hepatitis B or C mono-infection.
HEPATHER is a large cohort of people with hepatitis B and/or C, followed
at more than 30 centres in France, with centralised collection of biological
specimens. It aims to enrol 10,000 people with hepatitis B and 15,000 people
with hepatitis C.
This analysis looked at 14,698 participants enrolled as of November
2014. Within this group, 1099 had serological evidence of having been infected
with both HBV and HCV, while 9098 had HCV alone and 4501 had HBV alone. Of
these, 92 people with active HBV and HCV co-infection were matched by age, sex
and duration of infection with four people who had HBV alone and four with HCV
alone.
Rates of hepatitis delta (HDV) infection were similar for hepatitis B
patients with and without HCV, and HCV genotype distribution was the same for
hepatitis C patients with and without HBV.
People with HBV and HCV co-infection and those with HCV alone had
similar rates of advanced fibrosis or cirrhosis (Metavir stage F3-F4), but both
were significantly higher than the rate for people with HBV alone (42% and 40%
vs 15%, respectively).
People with co-infection were significantly more likely to have
low-level HBV DNA (<50 IU/ml) than those with HBV alone (87% vs 62%),
supporting the idea that HCV suppresses HBV. However, people with co-infection
and those with HCV alone were about equally likely to have high HCV RNA levels
(>6.1 log10) at enrolment (43% vs 49%).
People with co-infection were less likely to have received hepatitis C
treatment than people with HCV alone (51% vs 67%) and less likely to be on ongoing
hepatitis B treatment than those with HBV alone (29% vs 38%).
"HBV coinfection was not associated with the severity of
HCV-associated chronic hepatitis," the researchers summarised. "In
contrast, HCV coinfection harmfully impacted on fibrosis [in people with
HBV]." Interestingly, they added, "HCV coinfection may reduce HBV
replication in B/C coinfected patients."
Thus, they concluded, "HCV treatment initiation must be prioritized
in patients with an HBV/HCV coinfection, regardless of the severity of liver
disease."