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.
The antibody response against
Leishmania (
Leishmania)
amazonensis crude antigen was measured through the indirect immunofluorescent assay (IFA) and the immunoenzymatic assay (ELISA) in 114 patients ...with cutaneous leishmaniasis (CL) in Brazil. Fifty-four patients were infected by
Leishmania (
Viannia)
braziliensis, and 60 patients had
L. (
V.)
guyanensis infection. Patients were comparable by age, sex, disease duration and the Montenegro skin test diameter.
L. (
V.)
braziliensis-infected patients showed significant lower number of ulcerated lesions, greater ulcerated area and higher proportion of lymph node enlargement. Sensitivity of IFA was 79.6% (95% CI 66.1–88.9) and 71.7% (95% CI 58.4–82.2) for
L. (
V.)
braziliensis and
L. (
V.)
guyanensis-infected patients, respectively (
P
=
0.324). Sensitivity of ELISA was 98.2% (95% CI 88.8–99.9) and 85.0% (95% CI 72.9–92.5) for
L. (
V.)
braziliensis and
L. (
V.)
guyanensis-infected patients, respectively (
P
=
0.018). Significant differences were observed in the magnitude of the antibody response before treatment with higher levels detected in
L. (
V.)
braziliensis-infected patients by both serologic techniques. Eighty-four patients had serologic evaluations before and 12 weeks after treatment with meglumine antimoniate, 20
mg/kg/day for 20 days. Significant lower optic density values were observed after treatment with both species independent of cure or failure. Our data showed that
L. (
V.)
braziliensis induces a higher antibody response against
L. (
L.)
amazonensis antigens than
L. (
V.)
guyanensis and that down-modulation of the antibody response occurs shortly during disease evolution after treatment. Moreover the data support the use of ELISA as a better tool for detection of antibodies in CL.
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.
Eighty
Leishmania isolates from patients who contracted cutaneous leishmaniasis in the Manaus region, Amazonas State, Brazil, were identified as
Leishmania (
Viannia)
guyanensis by the ...electrophoretic profiles of six enzymes. None reacted with the species-specific monoclonal antibody B19. Two
L. (
V.)
guyanensis subpopulations were detected with the monoclonals B2 and B12. The lack of B19 expression by the
L. (
V.)
guyanensis strains in the present study contrasts with that of the vast majority of the strains of the same parasite from eastern Amazonia and French Guyana that express the epitope.
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.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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