Canine adenovirus type 1 and Pasteurella pneumotropica co‑infection in a puppy.

In 2008, a 2-month-old male German shepherd was presented with fever, depression, and evident organic wasting. The puppy died within 48 hours after the onset of clinical signs. A complete necropsy was performed. Bacteriological examination of samples from the brain, lung, liver, spleen, and bone marrow tested positive for Pasteurella pneumotropica. Histopathology demonstrated inflammatory and vascular lesions in the central nervous system and internal organs. Canine adenovirus type 1 (CAdV-1) nucleic acid was detected by polymerase chain reaction (PCR) in the frozen brain but not in the formalin-fixed, paraffin-embedded liver and lung samples. The positive PCR was subsequently confirmed by indirect fluorescent antibody testing of the paraffin-embedded brain and liver sections. Although the liver is the primary site of viral damage, these laboratory findings suggest that CAdV-1 infection should be included in the differential diagnosis of neuropathological diseases in dogs and that adenoviral infections could promote septicaemia caused by opportunistic pathogens.