Chronic kidney disease with three cases of oxalate-like nephrosis in Ragdoll cats

Abstract

Two unrelated Ragdoll cat mothers in Norway were found dead from renal disease. The histopathology was consistent with oxalate nephrosis with chronic or acute-on-chronic underlying kidney disease. Both cats had offspring and relatives with signs of urinary tract disease, including a kitten dead with urethral gravel. Eleven living Ragdoll cats, including nine relatives of the dead cats and the male father of a litter with similarly affected animals, were tested for primary hyperoxaluria (PH) type 1 and 2 by urine oxalate and liver enzyme analysis. Renal ultrasound revealed abnormalities in five living cats. One of these was azotaemic at the time of examination and developed terminal kidney disease 9 months later. A diagnosis of PH was excluded in 11 cats tested. The inheritance and aetiological background of the renal disease present in the breed remains unresolved at this point in time.

Pathogenesis of calcium oxalate urinary stone disease: species comparison of humans, dogs, and cats

“…Histopathologic findings from another cat with chronic kidney disease and calcium oxalate nephrolithiasis noted interstitial fibrosis, glomerular sclerosis, and multifocal lymphocytic aggregates in the kidneys, with no further details reported [90]. Three Ragdoll cats with chronic kidney disease that had a large number of oxalate crystals in tubules but without evidence of primary hyperoxaluria have also been described; one cat had concurrent nephroliths [91]. Other histologic abnormalities described were interstitial fibrosis, mononuclear inflammation, and atrophy of the tubular epithelium [91].…”

“…Three Ragdoll cats with chronic kidney disease that had a large number of oxalate crystals in tubules but without evidence of primary hyperoxaluria have also been described; one cat had concurrent nephroliths [91]. Other histologic abnormalities described were interstitial fibrosis, mononuclear inflammation, and atrophy of the tubular epithelium [91]. Cats with primary hyperoxaluria have bifringent crystals in the tubules and renal fibrosis [47, 48], with one cat also noted to have some crystals located in the interstitium, as well as interstitial nephritis and glomerulosclerosis [47].…”

A Case of Renal Oxalosis in a 3-Month-Old Cat Raised under Controlled Conditions

“…Both types of oxalosis or hyperoxaluria have been reported in many species including humans, dogs, cows, and cats [1,3,5,6,8,13,14]. In cats, most cases of renal oxalosis are an acquired disorder, and dietary components are noted as risk factors for increase of oxalate urolithiasis [13].…”

“…On the other hand, there are only a few reports of primary hyperoxaluria or hereditary renal oxalosis including both type 1 and type 2 in cats [1,3,5,8,14]. In the previous reports, primary hyperoxaluria in cats showed clinical features including acute renal failure and neurological signs and histological findings such as interstitial nephritis and fibrosis with crystal deposits, swollen axon in spinal cord and variation in fibre size in skeletal muscle [5,8,14]. In the present case, clinical dysfunction and histological findings in the kidney were similar with previous reports, but clear neurological signs were not observed.…”

Severe oxalate nephropathy in Zwartbles sheep

“…Primary hyperoxaluria is well recognised in human beings (Bobrowski and Langman 2008, Rumsby 2008, Hoppe and others 2009) and cats (McKerrell and others 1989, Goldstein and others 2009, Heiene and others 2009), where the genes responsible and the mode of inheritance (autosomal recessive) are well characterised. Reports of suspected disease also exist in Tibetan spaniels (Jansen and Arnesen 1990) and Beefmaster cattle (Rhyan and others 1992).…”