A histopathologic study of renal biopsies in fifty cases of leprosy.

Renal biopsies from 50 cases of leprosy, including 45 cases of lepromatous and 5 cases of tuberculoid, have been studied in detail histopathologically with special reference to any specific leprosy lesion such as the presence of leproma or granuloma, the presence of acid-fast bacilli and the occurrence of amyloid deposit. Leproma or granuloma, acid-fast bacilli and amyloid deposit could not be detected in any of these cases. Pathologic features of nephritis of various types were seen in only 40% of cases. Similar observations made by previous authors have been reviewed. The question is raised as to why kidney tissue should escape from developing specific leprosy lesions in either type of leprosy when other tissues such as liver, striated muscles and lymph nodes are known to develop such lesions. A greater immunologic resistance of the renal tissue to lepra bacilli or local physiochemical factors which may render renal tissue an unfavorable site for the settling and multiplication of lepra bacilli are considered as possible related factors.