[Electron microscopic investigation of the leishmaniasis cutanea. I. Leishmania tropica in the tissue (author's transl)].

On two patients suffering from Leishmaniasis cutanea from the old world florid and later a residual lesion could be removed for electron-mircroscopic examination, and the following was found: 1. A pseudocarcinomatous follicular epidermal proliferation in the florid lesion. 2. Macrophages with one to three Leishmania cells can be proved in histiocytes nests. The parasites are not always clearly surrounded by host cell membrane. 3. The endocellular Leishmania cells have a ciliary system which is open on the outside. It is, therefore, correct to speak of a cryptomastigotic shape of the flagellum. The kinetoplast shows direct transition to mitochondria. The number of periplast fibrillae or tubuli amounted to 95-97 which is less than in other types of Leishmania. Yet no further morphological distinctive feature between Leishmania tropica and the other types is discernible when a comparison with the pertinent literature is made. 4. No parasites to be considered virulent were found now in the late residual focus of previously secured cutaneous Leishmaniasis. The macrophages, on the other hand, contained big vacuoles with lamellar residual substances. These are regarded as rests of the parasites.