RESUMEN
In order to elucidate the mechanisms for the elimination of Leishmania, the histological evolution of the lesions of cutaneous leishmaniasis was studied in 118 biopsies from four geographical areas known to be associated with different species or sub-species of Leishmania. Basically there were 3 types of response: A, parasites were eliminated within intact macrophages which later evolved as epithelioid cells; B, they were eliminated as a result of the lysis of the macrophages either individually or in small clusters, but the process was incomplete; C, there was necrosis proceeding to completion at the centre of a focalised mass of macrophages. In B and C the release of parasites caused tissue destruction; epithelioid cells were immature and often sparse, though giant cells were seen in C. A more definite tuberculoid response was found in draining lymph nodes. The response (A, B or C) depended partly on the parasite load, partly on geographical factors. The relative proportions of macrophages, plasma cells and lymphocytes in the lesions varied with the parasite index, but the relationship was the same in all 3 types of response. This suggested that the 3 responses might be the outcome of a common immunological mechanism operating at different antigen levels or antigen-antibody ratios.
Asunto(s)
Leishmaniasis/patología , Piel/patología , Belice , Recuento de Células , Etiopía , Guyana , Humanos , Leishmaniasis/parasitología , Linfocitos/parasitología , Linfocitos/patología , Macrófagos/parasitología , Macrófagos/patología , Necrosis , Células Plasmáticas/parasitología , Células Plasmáticas/patología , Piel/parasitologíaRESUMEN
An outbreak of cutaneous leishmaniasis reached epidemic proportions among military personnel in Guyana during the period from November, 1977 to March, 1980. As the patients presented from widely separated areas of the hinterland it is likely that cutaneous leishmaniasis is endemic throughout the virgin tropical rain forest of Guyana, although infection is normally sporadic. A striking clinical feature was the 'spirotrichoid' involvement of the draining lymphatics and nodes in half the cases, which histologically all came from the middle region of the spectrum (groups II, III or IV of Ridley's 1980 classification). All the cases tested were serologically positive to a Leishmania braziliensis antigen. One hundred and ten patients were successfully treated with pentamidine, with minimal side-effects, but some required a second course. Four relapsed patients all belonged to the same histological group.
Asunto(s)
Brotes de Enfermedades/epidemiología , Leishmaniasis/epidemiología , Adolescente , Adulto , Niño , Femenino , Guyana , Humanos , Leishmaniasis/tratamiento farmacológico , Leishmaniasis/patología , Sistema Linfático/patología , Masculino , Pentamidina/uso terapéutico , Piel/patologíaAsunto(s)
Eritema Nudoso/patología , Lepra/patología , Comparación Transcultural , Humanos , Malasia , México , Necrosis , Nueva GuineaRESUMEN
Biopsies of skin and mucosal lesions were made on 60 well documented Brazilian patients with untreated cutaneous or mucocutaneous leishmaniasis, whose response to treatment was subsequently evaluated in 38 cases. The biopsies were examined with a view to classification after correlation with clinical and immunological findings. Although there was no simple or unified spectrum, five histological groups were defined and found to have some clinico-prognostic significance. In two groups the cases were all cutaneous with a relatively good prognosis. In another two groups they were evolving as mucocutaneous with a poor prognosis. The fifth group showed mixed characteristics with a tendency to relapse. There was no strong correlation with serum antibodies or Montenegro skin test, which were usually positive, or with parasite load, which was always low. The tissue response was distinguished from that in oriental sore by the degree of connective tissue involvement in all groups. It was the primary response in two groups, and subsidiary to a mono-nuclear response in the others. It suggested damage due to extra-cellular parasites or immune complexes. It did not correlate with the distinction between cutaneous and mucocutaneous disease. The single, most favourable, prognostic feature in either the cellular or connective tissue component was necrosis with a reactive response.
Asunto(s)
Leishmaniasis Mucocutánea/clasificación , Anticuerpos/análisis , Brasil , Humanos , Leishmaniasis/clasificación , Leishmaniasis/inmunología , Leishmaniasis/patología , Leishmaniasis Mucocutánea/inmunología , Leishmaniasis Mucocutánea/patología , Membrana Mucosa/patología , Piel/patologíaRESUMEN
Biopsies of skin and mucosal lesions were made on 60 well documented Brazilian patients with untreated cutaneous or mucocutaneous leishmaniasis, whose response to treatment was subsequently evaluated in 38 cases. The biopsies were examined with a view to classification after correlation with clinical and immunological findings. Although there was no simple or unified spectrum, five histological groups were defined and found to have some clinico-prognostic significance. In two groups the cases were all cutaneous with a relatively good prognosis. In another two groups they were evolving as mucocutaneous with a poor prognosis. The fifth group showed mixed characteristics with a tendency to relapse. There was no strong correlation with serum antibodies or Montenegro skin test, which were usually positive, or with parasite load, which was always low. The tissue response was distinguished from that in oriental sore by the degree of connective tissue involvement in all groups. It was the primary response in two groups, and subsidiary to a mono-nuclear response in the others. It suggested damage due to extra-cellular parasites or immune complexes. It did not correlate with the distinction between cutaneous and mucocutaneous disease. The single, most favourable, prognostic feature in either the cellular or connective tissue component was necrosis with a reactive response.