Occurrence of Kimmelstiel-Wilson like lesions in the absence of diabetic nephropathy in dogs, may provide a natural model for further research in the corresponding human form

Background: Nodular glomerulosclerosis occurring in non-diabetic patients is an unexplained renal condition that resembles Kimmelstiel-Wilson lesions (K-W), associated almost exclusively with diabetic nephropathy. This study aimed to assess the presence of nodular glomerulosclerosis in dogs with non-diabetic chronic kidney disease (CKD) and evaluate similarities with human condition, and thus, establish the dog as a natural disease model for further studies. Methods: Kidneys from dogs (n=27) with non-diabetic CKD were evaluated for the presence of nodular glomerulosclerosis. Samples were stained with haematoxylin-eosin and periodic acid of Schiff. Lesions were classified as absent or present, the later, classified as non-convincing and convincing K-W like lesions. Results: Nodular glomerulosclerosis was present in 66.66% of evaluated cases (n=18), of which, 38.88% (n=7) were convincing K-W like lesions and the remaining 61.11% (n=11), although similar, didn’t exhibit typical microscopic characteristics and were classified as non-convincing. Fibrosis was positively associated to diagnosis of K-W lesions (OR=6; p<0.05). Conclusion: As in man, Kimmelstiel-Wilson like lesions may also occur in dogs in the absence of diabetic nephropathy and reveal similar microscopic aspects to the description related in humans and, that some factors, others than hyperglycaemia, may be responsible for the appearance of these lesions. Thus, dogs may provide a model of natural disease for further elucidation.

This work was supported by Portuguese Foundation for Science and Technology, Center for Studies in Education, Technologies and by Health and by strategic project PEst-OE/CED/UI4016/2011