Clinical and parasite species risk factors for pentavalent antimonial treatment failure in cutaneous leishmaniasis in Peru
ABSTRACT Treatment for cutaneous leishmaniasis (CL) with standard pentavalent antimonial therapy is hampered by cumbersome administration, toxicity, and potential failure. Knowledge of factors influencing treatment outcome is essential for successful management.
A case-control study of incident cases was performed with patients experiencing their first CL episode. The standard treatment for CL for these patients was 20 mg/kg/day of sodium stibogluconate for 20 days. Clinical and epidemiological data were recorded, and parasite isolates were species typed. Patients were followed up for 6 months to assess treatment outcome. Clinical cure was defined as complete wound closure and re-epithelization without inflammation or infiltration; new lesions, wound reopening, or signs of activity were classified as treatment failure. Descriptive, bivariate, and logistic regression analyses were performed.
One hundred twenty-seven patients were recruited; 63 (49.6%) were infected with Leishmania (Viannia) peruviana, 29 (22.8%) were infected with Leishmania (Viannia) braziliensis, 27 (21.3%) were infected with Leishmania (Viannia) guyanensis, and 8 (6.3%) were infected with other species. Only patients infected with the 3 most common species were selected for risk-factor analysis (n=119). Final failure rate at 6 months was 24.4% (95% confidence interval [CI], 16.5%-32.1%), with 96% of failures occurring within the first 3 months of follow-up assessment. Risk factors for treatment failure identified in the final multivariate model were age (per year, odds ratio [OR], 0.95; 95% CI, 0.92-0.99; P=.017), stay of <72 months in area of disease acquisition (OR, 30.45; 95% CI, 2.38-389.25; P=.009), duration of disease <5 weeks (OR, 4.39; 95% CI, 1.12-17.23; P=.034), additional lesion (per lesion, OR, 2.06; 95% CI, 1.3-3.28; P=.002), infection with L. (V.) peruviana (OR, 9.85; 95% CI, 1.01-95.65; P=.049), and infection with L. (V.) braziliensis (OR, 22.36; 95% CI, 1.89-263.96; P=.014).
The identification of parasite species and clinical risk factors for antimonial treatment failure should lead to an improved management of CL in patients in Peru.
- SourceAvailable from: María Fernanda García Bustos[Show abstract] [Hide abstract]
ABSTRACT: Leishmaniasis, a disease caused by parasites of the Leishmania genus, constitutes a significant health and social problem in many countries and is increasing worldwide. The conventional treatment, meglumine antimoniate (MA), presents numerous disadvantages, including invasiveness, toxicity and frequent therapeutic failure, justifying the attempts at finding alternatives to the first-line therapy. We have studied the comparative long-term efficacy of MA against miltefosine (MF) in Leishmania infection in experimental mice. The criteria for efficacy evaluation were: footpad lesion size, anti-Leishmania antibodies level, histopathology of the site of inoculation (right footpad, RFP), splenic index (SI) and the presence of parasites in RFP, spleen and liver, determined by Polymerase Chain Reaction (PCR). Swiss mice, infected with L. (L.) amazonensis were treated, at different time points (5 and 40 days after infection) with either MA or MF. The efficacy of MF was better than that of MA for inhibiting lesions and for reducing tissue damage and presence/load of amastigotes in spleen and liver. Moreover, early administration of MF, produced a clear reduction in splenomegaly, and was equal in reducing antibody titles in comparison to MA. Our results demonstrated that MF is an effective and safe therapeutic alternative for leishmaniasis by L. (L.) amazonensis and is more efficacious than MA.Journal of Parasitology 12/2014; 100(6). DOI:10.1645/13-376.1 · 1.26 Impact Factor
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ABSTRACT: Leishmania are the causative protozoal agents of leishmaniasis, that is a significant cause of morbidity and mortality in more than 88 countries. In the absence of any effective vaccines, the only feasible way to treat leishmaniasis is through the use of medications. The first line drugs is composed of molecules developed in the 1950s, like pentavalent antimony (i.e., Pentostam®, Glucantime®). Currently Leishmania antimony resistance still continues to emerge in various part of the world. In Algeria, as early as 1986, a high rate of treatment failure (48.5%) was recorded during the treatment of cutaneous leishmaniasis caused by Leishmania major. In addition, lower sensitivity to meglumine antimoniate was observed in L. major isolated from Psammomys obesus, a reservoir host. More recently decrease antimony susceptibility was reported in L. infantum strains. The current studies engaged in Algeria on the susceptibility of Leishmania parasites will shed light not only on the occurrence of antimony resistance in this area but also on factors that are involved in the selection of antimony resistance in natural Leishmania populations.Microbial pathogens and strategies for combating them: science, technology and education, Edited by A. Mendez-Vilas, 12/2013: chapter Retrospective and ongoing researches on Leishmania antimony resistance in Algeria: pages 678-689; Formatex.
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ABSTRACT: The great public health problem posed by leishmaniasis has substantially worsened in recent years by the emergence of clinical failure. In Brazil, the poor prognosis observed for patients infected by Leishmania braziliensis (Lb) or L. guyanensis (Lg) may be related to parasite drug resistance. In the present study, 19 Lb and 29 Lg isolates were obtained from infected patients with different treatment outcomes. Translated amino acid sequence polymorphisms from four described antimony resistance related genes (AQP1, hsp70, MRPA and TRYR) were tested as candidate markers for antimonial treatment failure prediction. Possibly due to the low intraspecific variability observed in Lg samples, none of the prediction models had good prognosis values. Most strikingly, one mutation (T579A) found in hsp70 of Lb samples could predict 75% of the antimonial treatment failure clinical cases. Moreover, a multiple logistic regression model showed that the change from adenine to guanine at position 1735 of the hsp70 gene, which is responsible for the T579A mutation, significantly increased the chance of Lb clinical isolates to be associated with treatment failure (OR=7.29; CI 95%=[1.17, 45.25]; p=0.0331). The use of molecular markers to predict treatment outcome presents practical and economic advantages as it allows the development of rapid assays to monitor the emergence of drug resistant parasites that can be clinically applied to aid the prognosis of cutaneous leishmaniasis in Brazil.Acta tropica 02/2013; 126(2):132-141. DOI:10.1016/j.actatropica.2013.02.002 · 2.52 Impact Factor