Post-kala-azar dermal leishmaniasis: a histopathological study.

BACKGROUND Post-kala-azar dermal leishmaniasis follows an attack of visceral leishmaniasis and is caused by the same organism, i.e. Leishmania donovani. METHODS In the present study, biopsy specimens from hypopigmented macules, nodules or plaques of 25 patients clinically diagnosed as PKDL were evaluated for epidermal and dermal changes and for the presence or absence of Leishmania donovani bodies (LDBs). RESULTS The hypopigmented macules showed a patchy perivascular and periappendageal infiltrate with no demonstrable LDBs in any of the biopsies. In the nodular and plaque lesions, the infiltrate was diffuse, beneath an atrophic epidermis (74%) and follicular plugging (95.6%) was seen in most biopsies. The infiltrate consisted of lymphocytes, histiocytes and plasma cells in decreasing order of presence. LDBs could be demonstrated in only 10 (43.5%) biopsy specimens from nodular and plaque lesions and were never numerous. CONCLUSIONS Histopathological features of PKDL are elucidated and discussed.