Reovirus-associated meningoencephalomyelitis in baboons.

Baboon orthoreovirus (BRV) is associated with meningoencephalomyelitis (MEM) among captive baboons. Sporadic cases of suspected BRV-induced MEM have been observed at Southwest National Primate Research Center (SNPRC) for the past 20 years but could not be confirmed due to lack of diagnostic assays. An immunohistochemistry (IHC)-based assay using an antibody against BRV fusion-associated small transmembrane protein p15 and a conventional polymerase chain reaction (PCR)-based assay using primers specific for BRV were developed to detect BRV in archived tissues. Sixty-eight cases of suspected BRV-induced MEM from 1989 through 2010 were tested for BRV, alphavirus, and flavivirus by IHC. Fifty-nine of 68 cases (87%) were positive for BRV by immunohistochemistry; 1 tested positive for flavivirus (but was negative for West Nile virus and St Louis encephalitis virus by real-time PCR), and 1 virus isolation (VI) positive control tested negative for BRV. Sixteen cases (9 BRV-negative and 7 BRV-positive cases, by IHC), along with VI-positive and VI-negative controls, were tested by PCR for BRV. Three (of 9) IHC-negative cases tested positive, and 3 (of 7) IHC-positive cases tested negative by PCR for BRV. Both IHC and PCR assays tested 1 VI-positive control as negative (sensitivity: 75%). This study shows that most cases of viral MEM among baboons at SNPRC are associated with BRV infection, and the BRV should be considered a differential diagnosis for nonsuppurative MEM in baboons.

Evaluation of four hematology and a chemistry portable benchtop analyzers using non-human primate blood.

BACKGROUND: Near patient testing (NPT) and point-of-care testing (POCT) using portable benchtop analyzers has become necessary in many areas of the medical community, including biocontainment. METHODS: We evaluated the Beckman AcT diff, Abaxis Vetscan HMII (two instruments), Abbott Cell-Dyn 1800, and Abaxis Vetscan VS2 for within-run precision and correlation to central laboratory instruments using non-human primates blood. RESULTS: Compared with the central laboratory instruments, the Beckman AcT diff correlated on 80%; the HMII instruments on 31% and 44%, the CD1800 on 31%, and the VS2 on 71% of assays. For assays with published manufacturers precision guidelines, the AcT diff met all nine, the HMII instruments met one and six of six, and the CD 1800 met one of six. CONCLUSIONS: Laboratories using NPT/POCT must test their individual instruments for precision and correlation, identify assays that are reliable, and exclude or develop supplemental procedures for assays that are not.

Gastrointestinal stromal tumors in a baboon, a spider monkey, and a chimpanzee and a review of the literature.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are believed to originate from the intestinal pacemaker cells (interstitial cells of Cajal) or their progenitor cells. Spontaneous tumors have been reported in dogs, horses, rhesus, and a chimpanzee and they have been produced experimentally in mice and rats. GISTs represent a diagnostic challenge because they cannot be differentiated from non-lymphoid mesenchymal tumors without using human c-kit (CD117) immunohistochemistry. METHODS: Three neoplasms were incidental findings at necropsy in the stomachs of a baboon and a spider monkey and in the rectum of a chimpanzee. RESULTS: The GISTs were initially diagnosed grossly and histologically with hematoxylin and eosin as leiomyomas. Immunohistochemical analysis revealed that all three were c-kit (CD117) positive. CONCLUSIONS: These are the first reports of GISTs in the baboon and spider monkey and the second in a chimpanzee. The occurrence of GISTs in non-human primates may provide a unique opportunity to study these tumors.