Favorable responses to treatment with 5 mg Sbv/kg/day meglumine antimoniate in patients with American tegumentary leishmaniasis acquired in different Brazilian regions

Abstract INTRODUCTION: Favorable responses in American tegumentary leishmaniasis (ATL) patients to treatment with 5 mg Sbv/kg/day meglumine antimoniate (MA) has been reported in Rio de Janeiro, but little is known regarding the therapeutic response to low doses in patients from other locations. METHODS: A retrospective review of medical records was conducted to compare the therapeutic response to 5 mg Sbv/kg/day MA treatment among 36 patients who acquired ATL in Brazilian states other than Rio de Janeiro (OS group) and 72 patients from Rio de Janeiro (RJ group). RESULTS: One course of 5 mg Sbv/kg/day MA cured 72.8% of 81 cutaneous (CL) and 66.6% of 27 mucosal (ML) leishmaniasis-infected patients: 70% in the CL/RJ group, 81% in the CL/OS group, 50% in the ML/RJ group, and 80% in the ML/OS group. After up to two additional treatment courses at the same dose, 88.9% and 85.2% of the CL and ML patients were cured, respectively. Adverse events were observed in 40% of patients in the CL/RJ group, 57% of the CL/OS group, 58% of the ML/RJ group, and 80% of the ML/OS group. No significant differences were observed in the cure rates or adverse effects between the RJ and OS groups. No patients required permanent discontinuation of treatment due to adverse events. CONCLUSIONS: Patients with ATL acquired in both RJ and OS may respond to low-dose MA. While high-dose MA should remain the standard treatment for ATL, low-dose MA might be preferred when toxicity is a primary concern.

Prevalência da infecção canina em áreas endêmicas de leishmaniose tegumentar americana, do município de Paracambi, Estado do Rio de Janeiro, no período entre 1992 e 1993 / Prevalence of canine infection from endemic areas of American cutaneous leishmaniasis in Paracambi District, Rio de Janeiro State, between 1992 and 1993

No município de Paracambi, Estado do Rio de Janeiro, foi realizado um inquérito epidemiológico sobre a leishmaniose tegumentar americana na população canina residente em áreas endêmicas rural e semiurbana. Foram cadastrados 179 cães e 138 (77,1 por cento) foram examinados, segundo seus aspectos clínicos e desenvolvimento de hipersensibilidade tardia ao antígeno Imunoleish® e respostas sorológicas à reação de imunofluorescência indireta e ao ensaio imunoenzimático. Dos 9 (6,5. por cento) animais portadores de lesões/cicatrizes suspeitas, 66,7 por cento foram causadas por Leishmania sp; 44,4 por cento produziram infecção em hamsters e apresentaram crescimento em meio de cultura, compatíveis com o comportamento de Leishmania do complexo braziliensis. A caracterização molecular (análises isoenzimáticas e do perfil de restrição do KDNA) identificou 2 amostras como similares à Leishmania (Viannia) braziliensis. A prevalência da infecção canina observada através do teste cutâneo, RIFI e ELISA foi, respectivamente, 10,1 por cento, 16,7 por cento e 27,8 por cento. A presença das formas clínica/subclínica da LTA na população canina associada à infecção humana sugere que o cão pode atuar como possível fonte de infecção, assim como na disseminação da doença.

Diagnosis of human visceral leishmaniasis by PCR using blood samples spotted on filter paper

The polymerase chain reaction (PCR) is a simple, rapid procedure that has been adapted for the diagnosis of leishmaniasis. In the present study, 85 blood samples and seven bone marrow aspirates from 85 patients with clinical symptoms suggestive of visceral leishmaniasis from the metropolitan region of Belo Horizonte in the Brazilian State of Minas Gerais were screened using molecular and serological techniques. Samples that were negative (N = 12) and positive (N = 19) in parasitological and serological tests were used as controls. Of the 85 samples analyzed by PCR, 61 (71.7%) showed the expected amplification products in agarose gels. However, when the technique was combined with molecular hybridization, 72 samples (83.5%) gave a positive signal on film. Nineteen patients with Leishmania parasites in bone marrow cultures (positive controls) showed PCR hybridization in whole-blood samples, as did the seven bone marrow aspirates positive for Leishmania. None of the negative controls reacted in PCR or in an indirect immunofluorescent assay. These results indicate that PCR could replace the conventional parasitological examination in the diagnosis of leishmaniasis since it provides very satisfactory results with blood samples spotted on filter paper.

Parasite genotypically related to a monoxenous trypanosomatid of dog's flea causing opportunistic infection in an HIV positive patient

An HIV positive patient presenting a clinical picture of visceral leishmaniasis co-infection was submitted to a bone marrow aspiration after admission to hospital. Amastigotes forms were seen in the bone marrow aspirate and the parasite grew in culture as promastigotes. Molecular analyses showed that the flagellates isolated did not belong to the genera Leishmania, Trypanosoma or Sauroleishmania. It was not possible to establish infection in laboratory animals. In vitro culture of mouse peritoneal macrophages revealed the invasion of the host cells by the flagellates and their killing 48 hr after infection. Opportunistic infection with an insect trypanosomatid was suspected. Further hybridization analyses against a pannel of different monoxenous and heteroxenous trypanosomatids showed kDNA cross-homology with Leptomonas pulexsimulants a trypanosomatid found in the dog's flea.