Presumptive Hypertension Related Blindness (Ocular Disease) in Slender Loris (Loris tardigradus)
Renal disease, especially polycystic kidney disease, has been documented in slender lorises.3 Hypertension, anemia, and gastritis are common secondary findings in individuals with chronic renal disease, contributing to morbidity in these patients.4 At Brookfield Zoo, two slender lorises with documented renal disease presented with acute hyphema and suspected retinal detachment. Presentation and lesions were consistent with hypertensive lesions (renal hypertensive retinopathy) seen in other species.1,2 A survey was sent out to institutions that currently house or have previously housed slender lorises to determine the prevalence of renal and ocular disease in the North American captive population. Four institutions (Brookfield Zoo, Bronx Zoo, Cincinnati Metroparks Zoo, and Duke Primate Center) responded to the survey; 42 individuals are included in this report. Ocular disease (including: cataracts, retrobulbar abscesses, corneal ulcers, synechiae, and retinal degeneration) was diagnosed in ten animals. Seven animals exhibited evidence of renal disease (including: interstitial nephritis, polycystic kidney disease, and chronic glomerular nephritis). Five animals showed signs of ocular and renal disease, however, only two of these animals (mentioned previously) had ocular lesions suspected to be secondary to systemic hypertension. Hypertension was not routinely monitored for nor diagnosed in slender lorises.
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