Isolation of leishmania major from paraffinembedded skin biopsies of patients with sarcoidal type granuloma, using kinetoplast DNA-PCR [K-DNA PCR] technique

ABSTRACT

In the past, different causative agents were identified for sarcoidosis. However, recently new evidence points to an association between sarcoidosis and leishmaniasis. To further investigate this relationship, we performed a crosssectional study on paraffinembedded skin biopsy samples obtained from patients with clinical and histopathological diagnosis of cutaneous sarcoidosis referring to Skin Research Center of Shahid Beheshti University of Medical Sciences, in Tehran, from January 2001 to March 2005. In order to isolate leishmania parasite from their skin lesions, we employed conventional diagnostic criteria to detect infectious agents including leishmania parasites, we reexamined twentyfive paraffinembedded skin biopsies, diagnosed as naked sarcoidal granuloma, with no positive results obtained. Furthermore, DNA extracted from all specimens was analyzed by the commercially available polymerase chain reaction [PCR] kits. Out of twentyfive, eight samples were positive for leishmania major [L. major], whereas L. tropica was detected in none. In fact, from histopathological point of view, cutaneous leishmaniasis [CL] may be misinterpreted as sarcoidosis, all the more so in cases in which conventional methods fail to detect leishmania parasite. In endemic areas for leishmaniasis, PCR for leishmaniaspecific DNA should be utilized in any granulomatous skin disease compatible with sarcoidosis, regardless of both the clinical presentation and histopathological interpretation: