Abstract
Interstitial nephritis was observed in 118 of 215 (55%) dogs autopsied during a period from 1974 to 1975. More than 59% of dogs aged 4 years or over were found to have the renal lesions, while only 10% of these less than 1 year of age. Either diffuse or focal infiltration of mononuclear cells with fibrosis was recognized in the interstitium of these cases, some of which have very extensive tubular degeneration and necrosis. In 92 of these cases (78%) having interstitial nephritis there were diffuse or focal glomerular lesions characterized by thickening of the capillary wall, mesangial proliferation, hyalinization, sclerosing and amyloid deposition. Filariasis was the most frequent complication being detected in 67% of dogs with interstitial nephritis. On the other hand, interstitial nephritis was seen in 79 out of 102 (78%) dogs with filaria, while in 39 of 113 (35%) dogs without filaria. No inclusions suggesting canine hepatitis virus infection were seen in all cases examined. Another group of 26 dogs with interstitial nephritis were examined for leptospiral infection, revealing no leptospirae in the kidney tissue and only one antibody positive case.
