Domestic cat hepadnavirus associated with hepatopathy in cats: A retrospective study

Abstract

Background Whether domestic cat hepadnavirus (DCH) infection is associated with clinical disease remains to be determined. Objectives To determine the relationship between DCH detection, hematology, serum bichemistry and liver histology in DCH‐positive cats. Animals One thousand twenty‐two cats in Thailand without concurrent diseases and not undergoing treatments adversely affecting the liver. Methods Retrospective cross‐sectional study. Samples derived from cats with concurrent virus detection were excluded. DCH detection was determined in blood and fresh‐frozen liver by quantitative polymerase chain reaction (qPCR) and further investigated in liver sections showing histological parenchymal disorders (HPD) and normal liver (HNL) using in situ hybridization (ISH). Proliferative/apoptotic activities were determined using immunohistochemistry and ISH panels. Biochemical variables and risk factors for DCH infection were investigated. Results Six hundred sixty‐one (557 blood and 119 liver samples) cats were included. DCH was detected in 18.50% (103/557), 13.85% (9/65), and 3.70% (2/54) of the blood, HPD, and HNL groups, respectively. Cats with DCH revealed abnormally high activity of aspartate aminotransferase (AST) (P = .001) and alanine aminotransferase (ALT) (P < .001). Among DCH‐positive HPD case 2/9 an 7/9 were acute and chronic hepatitis, of which 4/7 had hepatitis. Log viral copy number (LVCN) was positively correlated with ALT (P < .001), triglyceride (P < .001), and gamma‐glutamyl transpeptidase (GGT) (P = .022). The LVCN also had a positive association with degree of hepatitis (P < .05). There was hepatocyte proliferation activity in DHC positive cats. Conclusion and Clinical Importance Domestic cat hepadnavirus infection was associated with high serum activity of liver enzymes and chronic lymphoplasmacytic hepatitis (LPH).

Domestic Cat Hepadnavirus: Molecular Epidemiology and Phylogeny in Cats in Hong Kong

“…This study showed that DCH is circulating among cats in Hong Kong, with a molecular prevalence of 11.1%, as measured by DCH DNA detection in whole blood. The prevalence in other regions varies widely, with DCH-positive cats apparently uncommon in the USA (0.2%) [ 11 ], Japan (0.78%) [ 12 ], and UK (1.9%) [ 10 ]; whereas virus DNA has been readily detected in cats in Australia (6.5%) [ 6 ], Italy (10.8%; 4.2%) [ 7 , 26 ], Thailand (18.5%) [ 15 ], and Malaysia (12.3%) [ 9 ]. Despite study design differences, it is likely that there are genuine regional differences in DCH prevalence, potentially caused by various transmission dynamics, as with human HBV [ 27 ].…”

“…No correlation was observed between serum ALT levels, a marker of hepatocellular injury, and DCH DNA detection, or virus load. In contrast, serum ALT was significantly associated with DCH DNA positivity in studies from Thailand and Malaysia [ 9 , 15 ]. A reported association between age >2 years and DCH detection [ 13 ] provided the rationale to exclude hyperthyroidism—a common cause of ALT elevation in cats > 8 years [ 16 ]—as a confounder in ALT analyses.…”

“…A potential role for DCH in feline liver disease is under investigation. Studies of feline liver biopsies reported an association between DCH DNA detection and hepatocellular carcinoma or hepatitis using cPCR, qPCR and in situ hybridization [ 14 , 15 ]. In addition, serological markers of liver disease have been identified as risk factors for DCH DNA positivity [ 7 , 9 , 15 ].…”

“…Studies of feline liver biopsies reported an association between DCH DNA detection and hepatocellular carcinoma or hepatitis using cPCR, qPCR and in situ hybridization [ 14 , 15 ]. In addition, serological markers of liver disease have been identified as risk factors for DCH DNA positivity [ 7 , 9 , 15 ]. Other risk factors for DCH viraemia include, in some studies, coinfection with feline immunodeficiency virus (FIV) or feline leukaemia virus (FeLV), and a weak association with age > 2 years [ 6 , 7 , 8 , 9 ].…”

Genetic diversity of domestic cat hepadnavirus in Taiwan

“…Following its initial discovery in Australia, investigation of DCH prevalence of this virus in cats from different countries have been carried out, with positive cases reported in Italy, Thailand, Malaysia, the United Kingdom, Japan, the United States, Hong Kong, and Türkiye [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. However, there is a lack of information regarding this virus in Taiwan, highlighting the importance of DCH investigation.…”