Amoebic meningoencephalitis and disseminated infection caused by Balamuthia mandrillaris in a Western lowland gorilla (Gorilla gorilla gorilla).

CASE DESCRIPTION A 22-year-old male gorilla (Gorilla gorilla gorilla) housed in a zoo was evaluated for signs of lethargy, head-holding, and cervical stiffness followed by development of neurologic abnormalities including signs of depression, lip droop, and tremors. CLINICAL FINDINGS Physical examination under general anesthesia revealed a tooth root abscess and suboptimal body condition. A CBC and serum biochemical analysis revealed mild anemia, neutrophilia and eosinopenia consistent with a stress leukogram, and signs consistent with dehydration. Subsequent CSF analysis revealed lymphocytic pleocytosis and markedly increased total protein concentration. TREATMENT AND OUTCOME Despite treatment with antimicrobials, steroids, and additional supportive care measures, the gorilla's condition progressed to an obtunded mentation with grand mal seizures over the course of 10 days. Therefore, the animal was euthanized and necropsy was performed. Multifocal areas of malacia and hemorrhage were scattered throughout the brain; on histologic examination, these areas consisted of necrosis and hemorrhage associated with mixed inflammation, vascular necrosis, and intralesional amoebic trophozoites. Tan foci were also present in the kidneys and pancreas. Immunohistochemical testing positively labeled free-living amoebae within the brain, kidneys, eyes, pancreas, heart, and pulmonary capillaries. Subsequent PCR assay of CSF and frozen kidney samples identified the organism as Balamuthia mandrillaris, confirming a diagnosis of amoebic meningoencephalitis. CLINICAL RELEVANCE Infection with B mandrillaris has been reported to account for 2.8% of captive gorilla deaths in North America over the past 19 years. Clinicians working with gorillas should have a high index of suspicion for this diagnosis when evaluating and treating animals with signs of centrally localized neurologic disease.

[Studies on the continuous culture and pathogenicity of Entamoeba gingivalis].

OBJECTIVE: To establish a method for continuous culture of Entamoeba gingivalis (E. g.) and study the pathogenicity of E. g.. METHODS: The culture conditions of E. g. were compared by observing its growth and reproduction. The pathogenicity of E. g. was studied by investigating its infection rate in humans and observing the relationship between E. g. infection and periodontal abscess in rats and the in vitro effect of some drugs. RESULTS: The optimal culture condition of E. g. was modified LES medium containing Locke's solution with 20% bovine serum, penicillin, streptomycin and rice starch. Reproduction of E. g. peaked at the fourth day of incubatoin, E. g. could live continuously for 120 to 168 h. The infection rate of E. g. was higher in patients with periondontal diseases than in healthy groups. The animal test showed that E. g. could cause periondontal abscess in rats. The levels of acid phosphatase and MDA were higher in patients with E. g.-positive periondontal disease than in healthy individuals. Metronidazole and SBF are effective against E. g.. CONCLUSION: E. g. could grow very well in modified LES medium, and cause periondontal abscess in patients with low immunity.