To the Editor: The presence of Kaposi sarcoma and leishmaniasis in the same cutaneous lesion, which has been observed in six cases (1-6), often reveals infection of peritumoral skin (1,3,4) (i.e., within the noninvolved areas immediately surrounding the abnormal portion of the skin biopsy). Subsequent to our previous report (4), we have seen two additional instances of leishmaniasis in perineoplastic dermis of Kaposi's sarcoma. A similar situation was described in the letter of Abajo et al. In contrast, the presence of Leishmania in clinically uninvolved skin (i.e., within a biopsy specimen taken distant from lesional skin) of human immunodeficiency virus (HIV)-infected patient with visceral leishmaniasis (VL) has not been looked for. As we mentioned in our article (4), only one patient had Leishmania in such "normal" skin documented with the technique of split-skin smear. However, with this procedure, a sharp distinction cannot be made between simple peripheral blood infestation of the dermis versus actual cutaneous involvement. Since our previous report (4), we have seen one additional case of "silent" leishmaniasis in two normal skin biopsy specimens of a HIV-infected patient with a prolonged fever, who had refused bone marrow aspiration. All cases demonstrating Leishmania in "normal" skin showed an extravascular pattern of infestation. This finding demonstrates, in HIV-infected patients with VL, a widespread involvement of skin by Leishmania, which differs from a simple peripheral blood dissemination. In comparison to bone marrow aspirate, the diagnostic value of peripheral blood smears for discovery of VL in HIV-infected subjects remain low (7). As with both marrow aspiration, normal results on skin biopsy could be useful in confirming the diagnosis of VL. On the other hand, in HIV-infected patients with Mediterranean VL the skin could act as a reservoir of infection and allow human-to-human transmission. Abajo et al. mention a new example of presumed "silent" leishmaniasis (E. F. Dandén, P. Penas, L. Rios, J. Fraga, J. Alvar, A. Garcia-Diez, unpublished observations). Although their report is not yet published, on the basis of their letter, two questions still remain to be answered. First, are their cases best categorized as cutaneous leishmaniasis or VL with a cutaneous involvement? The other unknown is whether or not the biopsy specimens demonstrating the "silent" leishmaniasis were obtained adjacent to or distant from the clinically apparent cutaneous lesion. C. Perrin, M.D. P. Del Giudice, M.D. B. Taillan, M.D. Y. Lefichoux, M.D. JF. Michiels, M.D. Departments of Pathology, Infectious Disease, Internal Medicine, and Parasitology Laboratory; University of Nice; Nice, France
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