The rarity of infection with Leishmania (Viannia) braziliensis among patients from the Manaus region of Amazonas state, Brazil, who have cutaneous leishmaniasis

The frequency of Leishmania ( Viannia) braziliensis infection was assessed in 79 of the 138 patients with cutaneous leishmaniasis who attended a reference outpatient unit in Manaus, Amazonas state, between the August and December of 1997. The disease was characterized by one or more cutaneous ulcers, the skin lesions being frequently associated with satellite lymph-node enlargement. All parasite isolates were identified using monoclonal antibodies and enzyme electrophoresis. Only two (2.8%) of the 71 patients from whom parasites were successfully isolated were found to be infected with L. ( V.) braziliensis, the other 69 isolates being identified, from their isoenzyme profiles, as L. ( V.) guyanensis. In the Manaus region, therefore, almost all human cutaneous leishmaniasis is the result of infection with L. (V.) guyanensis, and L. ( V.) braziliensis is a relatively rare cause of the disease.

Comparison of cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis and L. (V.) guyanensis in Brazil: therapeutic response to meglumine antimoniate

We conducted a quasi-experimental study to compare the response to meglumine antimoniate in patients with localized cutaneous leishmaniasis from two endemic areas of Brazil that were infected by two Leishmania species. Sixty-one were infected by Leishmania (Viannia) braziliensis (group B) and 57 by L. (V.) guyanensis (group G). All had a parasitologically proven diagnosis and were treated with 20 mg of pentavalent antimonial (SbV)/kg/day given intravenously or intramuscularly for 20 days. Main outcomes were diagnosed using clinical criteria three months after treatment and patients were followed for six months. Intention-to-treat analysis showed a higher failure rate in group G (relative risk [RR] = 1.5, 95% confidence interval [CI] = 1.1-2.0, chi2 = 7.44, P = 0.006). The analysis using an explanatory approach including 52 patients from group B and 49 from group G, who were regularly treated and followed for six months, showed a low cure rate (50.8% in group B and 26.3% in group G) with a greater risk of failure in the latter group (RR = 1.7, 95% CI = 1.2-2.5, chi2 = 8.56, P = 0.003). The effect of the etiologic agent remained significant after adjusting for age, disease duration, and site and number of lesions that were identified as predictors of failure in a logistic regression model. We concluded that Leishmania species constitute an important factor in predicting the outcome of cutaneous leishmaniasis treated with a pentavalent antimonial.

Sensitivity of the polymerase chain reaction for the diagnosis of cutaneous leishmaniasis due to Leishmania (Viannia) guyanensis

The sensitivity of the polymerase chain reaction (PCR) in 35 consecutive outpatients with cutaneous leishmaniasis caused by Leishmania (Viannia) guyanensis was evaluated using, as gold standard, the in vitro isolation of the parasite through culture of aspirates of the cutaneous ulcers. All isolates were identified using electrophoretic enzyme analysis. Patients were mainly young males with recent onset disease without prior specific treatment. PCR was performed using DNA extracted from fresh frozen biopsies of cutaneous ulcers. The reaction used a pair of oligonucleotides that amplify the conserved region of the minicircle molecule. PCR showed 100% sensitivity (95% CI from 90.0 to 100.0). These results were similar to the visualization of amastigotes in imprint preparations of cutaneous biopsy tissue and the inoculation of biopsy material in golden hamsters. Despite the high sensitivity of the PCR, in this particular clinical setting of cutaneous leishmaniasis caused by L. (V.) guyanensis in the Brazilian Amazon, it appears that the method of choice for diagnosis should be the direct visualization of amastigotes using imprint preparations and the PCR reserved for those patients with negative imprint results.

[Evaluation of secondary bacterial infection's influence on the course of cutaneous leishmaniasis in Corte de Pedra, Bahia]

In order to study the prevalence of secondary bacterial infection in ulcerated lesions and its relationship to the healing process, 84 leishmaniotic patients were evaluated. Diagnosis of the secondary infection was made by bacterial aerobic culture of peripheral tissue specimen of the ulcer. All patients received antimonial therapy during 20 days and washed their ulcers with common soap. Cases were composed mainly of adolescent and adult farmer patients with single lesions. The evaluated ulcers were encountered on legs and feet in 47.6%. Secondary bacterial infection was found in 45/83 (54.2%), and was more frequent in lesions located below the knee. Staphylococcus aureus predominated (89%). The ulcers' healing process, evaluated in 79 patients one month after finishing treatment, was not influenced by the secondary bacterial infection.

[Socioeconomic factors and attitudes towards household prevention of American cutaneous leishmaniasis in an endemic area in Southern Bahia, Brazil]

A survey was conducted to identify socioeconomic conditions and attitudes towards household prevention of American cutaneous leishmaniasis in Corte de Pedra, located in the county of Tancredo Neves, an endemic region in southern Bahia, Brazil. A questionnaire was applied in July 1997, focusing on social and economic variables, habits, and attitudes towards prevention of arthropod bites. All families (100%) living in the study area were surveyed, comprising 168 households with 851 individuals. Approximately 66.7% of the families earned up to one minimum wage, supporting an average of 5.1 residents per household. Most (57.2%) of the families did not use any type of protection against bites. Fumigation by burning various types of materials was the most customary form of prevention. Individual protection measures were rarely used. Since there was evidence of household and peridomiciliary transmission in the study area, use of impregnated bed nets is an alternative for intradomiciliary protection.

[Treatment of mucosal leishmaniasis with aminosidine sulfate: results of two year follow-up]

In 1996, 20 of 21 patients with mucosal leishmaniasis, treated in 1994 with aminosidine sulfate, 16mg/kg/day salt, by intramuscular injection for 20 days, were clinically evaluated. One patient died due to disease not related to mucosal leishmaniasis. Seven of 14 patients (66.7% N = 21) who achieved complete remission three months after treatment remained clinically cured 24 months later and seven relapsed in the same period (50% N = 14). Sorological follow-up showed poor correlation with the results of clinical examination.

Clinical observations of unresponsive mucosal leishmaniasis

We report the long-term clinical follow-up of two patients with unresponsive mucosal leishmaniasis due to Leishmania (Viannia) braziliensis from the Três Braços area in Bahia State, Brazil. Both were agricultural male workers with extensive upper respiratory mucosal involvement that was not cured with conventional and experimental therapy.

[Open therapeutic study with aminosidine sulfate in mucosal leishmaniasis caused by Leishmania (Viannia) braziliensis]

From September to November 1994. 21 patients with active mucosal leishmaniasis were treated with aminosidine sulphate 16 mg/kg/day by intramuscular injection for 20 days. They were principally adult male agricultural workers. Thirteen patients had not received specific treatment and eight had failed to respond to Glucantime therapy. Diagnosis was based on clinical and epidemiological observations, a search for the parasite, leishmanin skin sensitivity and indirect fluorescent antibody serological tests. Sixty seven percent of patients had leishmania parasites isolated from inoculated hamsters or visualized in imprints or histopathological sections. The mean follow-up period was 12.6 months. All patients completed treatment. Side effects were pain at the injection site (86%); mild proteinuria (24%), elevated serum creatinine (.5%) and subclinical bearing loss in one of two patients who did audiometric tests. Clinical cure was achieved in 48% and the accumulated relapse rate was 29% (4/14).

[Comparative study of meglumine antimoniate, pentamidine isethionate and aminosidine sulfate in the treatment of primary skin lesions caused by Leishmania (Viannia) braziliensis]

With the aim of comparing the therapeutic efficacy, tolerability and toxicity of meglumine antimoniate, aminosidine sulphate and pentamidine isethionate, a field study was conducted on randomized treatment of patients with primary cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis (L(V)b), in Corte de Pedra, BA, from October 1992 up to January 1993. Forty six patients were treated and distributed into three groups, two with 15 and one with 16 subjects. All patients were submitted to clinical examination, histopathological and immunological investigations, as diagnostic criterium. All patients were treated by intramuscular route. Group 1 received pentamidine 4 mg/kg/every 2 days, for 8 applications; Group 2 received aminosidine 20 mg/kg/day, for 20 days, and Group 3 received meglumine 10 mg Sbv/kg/day, for 20 days. Failure of therapy was defined as ulceration of the skin lesion four months after treatment. Such failure occurred in five cases as follows: two cases in patients of group 1 one case in patients of group 2, and two cases in group 3, after the first year of follow up. In the evaluation after three years we reviewed fifteen patients, five in each group; except for one in Group 3, all of them were cured. Statistical significance of the results between the three schedules used was not verified.