A Clinicopathologic Analysis of Leprosy

Abstract

Background: In Korea, the prevalence of leprosy and the number of new indigenous cases has fallen. With this reason, the diagnosis of leprosy is not as easy as in the past and it became more dependent of the histopathologic features by skin biopsy. Object: The aim of this study was to document and analyze the clinical and histopathological features of leprosy in Korea. Methods: We carried out the clinical and histopathological studies on 90 leprosy patients who visited the Institute of Leprosy Control during the period from Jan. 1998 to Aug. 2002. Results: The results obtained were as follows. 1. Elongated granulomas which are frequently observed in the leprosy lesions, was not present in the 3 cases(18.7%) of T types, 2 cases(28.6%) of B types and 17 cases(27.9%) of L types of leprosy. 2. In the L type of leprosy, infiltration of foamy cells showed elongated(63.9%) or nodular(27.9%) patterns more than typical diffuse infiltrative pattern(8.2%). 3. Selective nerve involvement by lymphocytes was found in 2 cases of L types of leprosy. 4. In the B type and the L type leprosy, prominent nerve involvement and neural destruction was not found in 1 and 7 cases, respectively and sparse to mild infiltration of foamy cells was found in 71.4% and 34.4%, respectively. Conclusion: In the histopathological diagnosis of T type leprosy, elongated or even round granuloma, perineurial lymphocytic infiltration and nerve remnant in the granuloma was characteristic. As for L type of leprosy, we should know that in 1/3 cases, it can show only sparse to mild infiltration of foamy cells and there is no obvious nerve abnormalities. Therefore, these results suggest that many cases of leprosy can show atypical histopathological findings and we should take caution in the diagnosis of leprosy.