Systemic Staphylococcus pseudintermedius infection in an arctic fox (Vulpes lagopus) with severe multifocal suppurative meningoencephalitis and nephritis.

A 2-year-female arctic fox (Vulpes lagopus) developed anorexia, dehydration, and emaciation during the quarantine period for importation from Norway, and died 17 days later. At necropsy, a fistula was observed on the left gluteal region, and the left eye, left brain, and kidneys were discolored. Histologically, severe diffuse suppurative meningoencephalitis and renal abscesses were detected. Numerous Gram-positive cocci were detected in these lesions. Multidrug-susceptible Staphylococcus pseudintermedius were isolated from the lesions. These results suggest that S. pseudintermedius can cause severe multifocal suppurative meningoencephalitis and nephritis in foxes. This is the first report of multidrug-susceptible S. pseudintermedius meningoencephalitis and nephritis in a fox.

Septicemic invasive Klebsiella pneumoniae infection in a cynomolgus monkey (Macaca fascicularis) with severe diffused suppurative meningoencephalitis.

A 2-year-old male cynomolgus monkey (Macaca fascicularis) showed neurological symptoms during quarantine for importation into Japan, and was euthanized due to poor prognosis. Gross anatomical examination revealed a hemorrhagic lesion around the lateral ventricle in the cerebrum. Histologically, severe diffused suppurative meningitis and ventriculitis were detected with numerous Gram-negative bacilli in the cerebrum. Immunohistochemically, the bacilli were positively stained with an antibody against Klebsiella pneumoniae. The bacterium was isolated from the liver, and it was confirmed to be K. pneumoniae by 16S rDNA sequencing. The isolate displayed a hypermucoviscosity phenotype, was positive for the rmpA and k2A genes, and demonstrated multidrug resistance. These results suggest that invasive K. pneumoniae can cause septicemic infection, characterized by severe diffused suppurative meningoencephalitis in monkeys.

Three Cases of Escherichia coli Meningitis in Chicks Imported to Japan.

Three outbreaks of colibacillosis have occurred in chicks during the quarantine period after importation to Japan. All three were derived from three different countries without epidemiologic relevance. Some birds from each infected flock were examined pathologically and bacteriologically. The characteristic histologic finding common to all three cases was severe bacterial meningitis in the central nervous system. Pericarditis, perihepatitis, and omphalitis with bacterial colonies were also observed. The bacterial colonies observed histologically were immunohistochemically positive for Escherichia coli antigens. Escherichia coli was isolated from the organ samples from each outbreak. At least two E. coli isolates were serotyped as O18 and O161, which differed from the popular serotypes in Japan. These results suggest that avian pathogenic E. coli of uncommon serotypes can be imported from outside countries by infected chicks. Colibacillosis should be included in the differential diagnosis when meningitis is histologically observed in chicks.

Multifocal suppurative granuloma caused by Actinobacillus lignieresii in the peritoneum of a beef steer.

An imported crossbred Angus beef steer aged eight to twelve months died suddenly on the eighth day of a quarantine period in Japan. Gross examination showed the peritoneum and mesentery consisted of numerous nodules of various sizes. Histological examination revealed chronic suppurative granulomatous peritonitis with eosinophilic rosettes surrounding colonies of Gram-negative bacilli. The bacteria isolated from the nodules were confirmed to be Actinobacillus lignieresii based on the results of 16S rRNA gene sequencing and immunohistochemistry. Antibiotic sensitivity testing showed that the isolate was resistant to penicillin. Thus, a diagnosis of atypical actinobacillosis caused by A. lignieresii was made.