Leucoencephalopathy with cerebral calcinosis in a young chimpanzee (Pan troglodytes) - a case report

Epilepsy in nonhuman primates

OBJECTIVES

Nonhuman primates (NHPs) are model organisms for understanding the pathophysiology and treatment of epilepsy in humans, while data from human patients informs the diagnosis and treatment of NHP with seizures and epilepsy. We reviewed the literature and surveyed veterinarians at zoos and NHP research centers to (a) better define the range of seizures and epilepsy in NHP, (b) understand how NHPs can inform our knowledge of the pathophysiology and treatment of epilepsy in humans, and (c) identify gaps of knowledge and develop more effective guidelines to treat seizures and epilepsy in NHP.

METHODS

We searched PrimateLit, PubMed, and Google Scholar for studies on experimental models of epilepsy in NHPs and on naturally occurring seizures and epilepsy in NHPs in captivity. In addition, we created a survey to assess methods to diagnose and treat epilepsy in NHPs. This survey was sent to 41 veterinarians at major international zoos and research facilities with NHP populations to study seizure phenomenology, diagnostic criteria for seizures and epilepsy, etiology, and antiseizure therapies in NHPs.

RESULTS

We summarize the data from experimental and natural models of epilepsy in NHPs and case reports of epilepsy of unknown origin in captive primates. In addition, we present survey data collected from veterinarians at eight zoos and one research facility. Experimental data from NHP epilepsy models is abundant, whereas data from primates who develop epilepsy in the wild or in zoos is very limited, constraining our ability to advance evidence-based medicine.

SIGNIFICANCE

Characterization of seizure or epilepsy models in NHPs will provide insights into mechanisms and new therapies that cannot be addressed by other animal models. NHP research will better inform species-specific diagnoses and outcomes.

Natural pathology of the captive chimpanzee (Pan troglodytes): A 35-year review

We present the spontaneous pathological lesions identified as a result of necropsy or biopsy for 245 chimpanzees (Pan troglodytes) over a 35-year period. A review of the pathology database was performed for all diagnoses on chimpanzees from 1980 to 2014. All morphologic diagnoses, associated system, organ, etiology, and demographic information were reviewed and analyzed. Cardiomyopathy was the most frequent lesion observed followed by hemosiderosis, hyperplasia, nematodiasis, edema, and hemorrhage. The most frequently affected systems were the gastrointestinal, cardiovascular, urogenital, respiratory, and lymphatic/hematopoietic systems. The most common etiology was undetermined, followed by degenerative, physiologic, neoplastic, parasitic, and bacterial. Perinatal and infant animals were mostly affected by physiologic etiologies and chimpanzee-induced trauma. Bacterial and physiologic etiologies were more common in juvenile animals. Degenerative and physiologic (and neoplastic in geriatric animals) etiologies predominated in adult, middle aged, and geriatric chimpanzees.

Natural mortality and cause of death analysis of the captive chimpanzee (Pan troglodytes): A 35-year review

We present the spontaneous causes of mortality for 137 chimpanzees (Pan troglodytes) over a 35-year period. A record review of the pathology database was performed and a primary cause of mortality was determined for each chimpanzee. The most common causes of mortality were as follows: cardiomyopathy (40% of all mortalities), stillbirth/abortion, acute myocardial necrosis, chimpanzee-induced trauma, amyloidosis, and pneumonia. Five morphologic diagnoses accounted for 61% of mortalities: cardiomyopathy, hemorrhage, acute myocardial necrosis, amyloidosis, and pneumonia. The most common etiologies were degenerative, undetermined, bacterial, traumatic, and neoplastic. The cardiovascular system was most frequently involved, followed by the gastrointestinal, respiratory, and multisystemic diseases. Degenerative diseases were the primary etiological cause of mortality of the adult captive chimpanzee population. Chimpanzee-induced trauma was the major etiological cause of mortality among the perinatal and infant population. This information should be a useful resource for veterinarians and researchers working with chimpanzees.