title: Cerebellar abscess in a cynomolgus macaque (Macaca fascicularis).
abstract: BACKGROUND
  A cynomolgus macaque (Macaca fascicularis) presented with decreased appetite, lethargy, ataxia, disorientation and visual impairment. It was used in a hepatitis B (HBV) study involving injections of HBV plasmid construct (450 microg) and aflatoxin B1 (25 microg/kg) in an effort to develop a model of liver cirrhosis and hepatocellular carcinoma.
  
  
  METHODS
  The case work-up included physical examination, including assessment of hydration, thoracic and abdominal radiographs and abdominal ultrasound. Clinical pathology included complete blood counts and tests for levels of plasma ammonia (NH(3)) and serum electrolytes, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, total bilirubin, and gamma-glutamyl transferase. Serum samples had also been serially tested for the presence of HBsAg, anti-HBc antibodies, HBV e-antigen, and HBV DNA. With a tentative diagnosis of hepatic encephalopathy, treatment with lactulose, antibiotics, and fluid therapy was initiated.
  
  
  RESULTS
  Clinical pathology and diagnostic imaging performed on the animal revealed no abnormalities except for the hyperammoniemia. Absence of HBV markers in the serum indicated unsuccessful inoculation. Not fully responding to therapeutic intervention, the animal was euthanized. Necropsy revealed fibrous peritoneal adhesions and an abscess in the cerebellopontine angle. Exudate culture indicated the presence of alpha-hemolytic streptococcus, Eubacterium lentum, and Bacteroides stercoris.
  
  
  CONCLUSIONS
  Brain abscesses are uncommon in non-human primates. This case of cerebellar abscess is characterized by important features similar to that found in humans, including the presenting signs and the presence of the above-cultured bacteria.
authors.affiliation: Department of Experimental Surgery, Singapore General Hospital, Outram Road, Singapore. jasonvillano@yahoo.com
authors.forename: Jason So
authors.initials: JS
authors.lastname: Villano
authors.forename: Bryan
authors.initials: B
authors.lastname: Ogden
authors.forename: Angela
authors.initials: A
authors.lastname: Goh
authors.forename: Lai Siang
authors.initials: LS
authors.lastname: Hui
authors.forename: Pierce K H
authors.initials: PK
authors.lastname: Chow
mesh_terms: D000818:Animals; D001066:Appetite; D001259:Ataxia / Q000662:veterinary; D001439:Bacteroides / Q000302:isolation & purification; D001922:Brain Abscess / Q000175:diagnosis / Q000382:microbiology / Q000662:veterinary*; D002526:Cerebellar Diseases / Q000175:diagnosis / Q000382:microbiology / Q000662:veterinary*; D005051:Eubacterium / Q000302:isolation & purification; D037901:Euthanasia, Animal; D053609:Lethargy / Q000662:veterinary; D008297:Male; D008992:Monkey Diseases / Q000175:diagnosis* / Q000382:microbiology / Q000628:therapy; D013291:Streptococcus / Q000302:isolation & purification; D014786:Vision Disorders / Q000662:veterinary