Pathological Features of Oxalate Nephrosis in a Population of Koalas (Phascolarctos cinereus) in South Australia

• DOI: 10.1177/0300985812456215
• Publication Date: 2012-08-02T06:36:25Z
• Authors: K. N. Speight; W. Boardman; W. G. Breed; D. A. Taggart; L. Woolford; J. I. Haynes
• Keywords: Nephrosis; Phascolarctos cinereus

The wild and captive koala population of the Mt Lofty Ranges in South Australia has a high level renal dysfunction which crystals consistent with calcium oxalate have been observed kidneys. This study aimed to describe pathological features disease this population, confirm composition as oxalate, determine whether any age or sex predispositions exist for disease. A total 51 koalas (28 rescues, 23 captive) were examined at necropsy, 28 (55%) found gross and/or histological evidence nephrosis. Histopathological included intratubular interstitial inflammation, tubule dilation, glomerular atrophy, loss, cortical fibrosis. Calcium demonstrated using combination polarization microscopy, alizarin red S staining, infrared spectroscopy, energy-dispersive X-ray analysis scanning electron microscopy. Uric acid phosphate deposits also shown be present but associated minimal histopathological changes. No significant differences between numbers affected rescued koalas; also, there no identified, it was that nephrosis may affect <2 years age. findings suggest is leading population. Possible causes are currently under investigation.