Percutaneous kidney biopsies were performed on thirteen patients with leptospirosis. The method is considered to be safe and in some cases useful for research and diagnostic purposes. Since the specific agglutination test may not become positive for a relatively long time, the biopsy can provide confirmatory evidence in doubtful cases.
No marked difference was found between the histopathological findings of autopsy and at biopsy except that the lesions in biopsy material were less severe and more focal. A close similarity was noted between acute tubular necrosis and the interstitial nephritis seen in leptospirosis, the peculiarities in the latter being determined by the recurrent character of this entity. The functional impairment can possible also be explained by the observation that mitochondria of tubule cells were markedly depleted in the regenerating epithelium.