Evaluating the presence of domestic cat hepadnavirus viraemia in cats with biochemical alterations suggestive of liver disease

Background: The association between domestic cat hepadnavirus (DCH) infection and feline chronic hepatitis and hepatocellular carcinoma has been suggested. However, studies focused on the association between DCH infection and clinicopathological changes consistent with liver disease in cats are not available. Methods: This retrospective investigation included sera obtained from 96 cats that had the serum activity of at least alanine aminotransferase or alkaline phosphatase measured during initial diagnostic work-up. Based on these haematobiochemical results, cats were categorised according to their likelihood of having liver disease (absent, low, intermediate or high). DCH DNA was detected using real-time PCR, nested PCR and sequencing. Results: Overall, potential liver damage was observed in 44 cats, including cats with low (n = 14), intermediate (n = 10) and high (n = 20) likelihood of liver disease. Four cats (4.2%) were DCH-positive, with three positive cats belonging to the liver disease group (two with low and one with intermediate likelihood of liver disease). Conclusions: Although the pathogenic potential of DCH in cats still has to be clarified, these results suggest that DCH testing should not be based only on the presence of biochemical changes potentially consistent with liver disease.