Feline herpesvirus (FHV) is well known cause of upper respiratory tract disease. Less commonly, it is also associated with inflammatory oral disease (stomatitis) and dermatitis, primarily on the face. Cats with FHV dermatitis have erythema, swelling, crusting, and ulceration typically around the muzzle and around the eyes. Diagnosis may be difficult as it relies on finding intranuclear viral inclusion bodies on biopsy samples. Many cases are misdiagnosed as eosinophilic granuloma complex (EGC) or another skin disease. This study used immunohistochemistry (IHC) and histopathology to detect the presence of FHV in biopsy samples from cats suspected of having EGC, other eosinophilic skin diseases, and stomatitis. Cases were taken from samples submitted to the University of Sydney between 1996 and 2008. Of the 30 cases examined, two showed a positive reaction for FHV using IHC. In both cases, intranuclear inclusion bodies were found on histopathology, but were difficult to detect. The authors conclude that FHV is uncommonly associated with EGC or similar skin diseases in cats in Sydney, Australia. They also point out that misdiagnosis can easily occur, and FHV should be considered in cats with severe ulcerative skin lesions, especially when unresponsive to corticosteroid treatment. IHC is helpful to differentiate FHV dermatitis from other skin diseases. [SL]
Malik R, Lessels NS, Webb S et al: Treatment of feline herpesvirus-1 associated disease in cats with famciclovir and related drugs, Journal of Feline Medicine & Surgery 11:40-48, 2009.