Characterization of a Cardiorenal-like Syndrome in Aged Chimpanzees (Pan troglodytes)

Abstract

Cardiorenal syndrome involves disease and dysfunction of the heart that leads to progressive renal dysfunction. This study investigated the relationship between cardiac and renal disease in 91 aged chimpanzees at the Alamogordo Primate Facility by evaluation of the medical histories, metabolic parameters, functional measurements of the cardiovascular system, clinical pathology, and histopathology focused on the heart and kidney. Cardiac fibrosis was the most frequent microscopic finding in 82 of 91 animals (90%), followed by glomerulosclerosis with tubulointerstitial fibrosis in 63 of 91 (69%). Cardiac fibrosis with attendant glomerulosclerosis and tubulointerstitial fibrosis was observed in 58 of 91 animals (63%); there was a statistically significant association between the 2 conditions. As the severity of cardiac fibrosis increased, there was corresponding increase in severity of glomerulosclerosis with tubulointerstitial fibrosis. Altered metabolic, cardiovascular, and clinical pathology parameters indicative of heart and kidney failure were commonly associated with the moderate to severe microscopic changes, and concurrent heart and kidney failure were considered the cause of death. The constellation of findings in the chimpanzees were similar to cardiorenal syndrome in humans.

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

“…Lesions of the cardiovascular system accounted for over 50% of all mortality, which is consistent with previous reports of heart disease as the #1 cause of mortality among captive chimpanzee populations [5, 6, 19, 23, 27, 28]. The majority of the cardiovascular cases in this report were classified as cardiomyopathy, a poorly understood entity, characterized by interstitial myocardial fibrosis.…”

“…The majority of the cardiovascular cases in this report were classified as cardiomyopathy, a poorly understood entity, characterized by interstitial myocardial fibrosis. Chimpanzee cardiomyopathy is more common in males and manifests clinically as cardiac arrhythmias, sudden death, or chronic heart failure [3, 5, 6, 19, 23, 25, 27, 29]. The gastrointestinal system was the second most common affected system (14%), including four cases of hepatocellular carcinoma, and three cases each of intussusception, enteritis, and colitis.…”

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

“…The high incidence of cardiomyopathy in chimpanzees could suggest a genetic component and warrant further investigation of this pathology relative to genealogy. Hemosiderosis, edema, hemorrhage, ascites, hydrothorax, and hydropericardium were often interpreted as sequela of cardiac insufficiency due to cardiomyopathy . Renal lesions were most common in middle aged to geriatric groups, and the two primary diagnoses were nephritis and glomerulonephritis, which is consistent with previous literature…”

“…Cardiovascular disease, specifically, cardiomyopathy (also known as cardiac fibrosis or interstitial myocardial fibrosis), is reported to be the primary cause of mortality in captive chimpanzees in several previous publications and was the most common morphologic diagnosis in this study . The high incidence of cardiomyopathy in chimpanzees could suggest a genetic component and warrant further investigation of this pathology relative to genealogy.…”

“…This dataset provides significant insights into the natural pathology of captive chimpanzees. While some data regarding specific aspects of captive and wild chimpanzee pathology have been reported before, this publication provides an exhaustive account of all lesions across all age groups over a significantly long period of time (35‐years). It is our hope that the information presented in this publication should serve as a reference for the veterinarians, care givers, and investigators working with chimpanzees.…”