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Accurate identification of Leishmania species is important for monitoring clinical outcome, adequately targeting treatment, and evaluation of epidemiological risk in tegumentary leishmaniasis. This is especially the case in regions where several species coexist and for travel medicine where the geographical source of infection is not always obvious. Species identification presently depends on parasite isolation, which is not very sensitive and not necessarily representative of parasites actually present in human tissues. We evaluated a polymerase chain reaction (PCR) assay combining amplification of the gp63 genes and restriction fragment length polymorphism (RFLP) analysis (gp63 PCR-RFLP) for direct Leishmania species-identification in tissues collected from Peruvian patients in 1999. By comparison with a kinetoplast DNA-based PCR, our PCR assay showed a detection sensitivity of 85%. Three species were encountered among patient samples, Leishmania (Viannia) braziliensis, L. (V.) peruviana and L. (V.) guyanensis, and their frequency and geographical distribution corresponded to earlier epidemiological studies of leishmaniasis in Peru. However, unexpected results raised questions about (i) the contribution of human migration to the emergence of new foci of given species, (ii) the pathogenicity of some species, and (iii) the frequency of mixed or hybrid infections.

Objective: To compare the efficacy and safety of sodium stibogluconate (SS) and meglumine antimoniate (MA) in the treatment of cutaneous leishmaniasis (CL) in a general hospital. Methods: Case-series of 193 patients with CL treated in three clinical trials with MA (n=69) and SS (n=124) during 2001-2010. Both study drugs were administered intravenously at a slow speed at 20 mg Sb5+/kg/day for 20 consecutive days following WHO-PAHO recommendations. Clinical and safety data were gathered from clinical files. Results: Demographic characteristics were similar between the study groups, but the size and number of lesions were higher in the MA group. Efficacy was 76.0% in the MA vs. 68.4% in the SS group (p=0.340) and 55.1% vs. 50.8% (p=0.570) in the per protocol and intention to treat analysis. respectively. Side effects more frequently reported were dysgeusia (37.0%). dizziness (32.0%). headache (36.0%). arthralgia (31.0%) and lymphangitis (21.0%). These first three symptoms as well as elevation of transaminases, leukopenia, thrombocytopenia and prolonged QTc were numerically more frequent in the SS group but without reaching statistical significance. Treatment was stopped definitively for severe toxicity in the SS group due to refractory emesis (two patients) and prolonged QTc (one patient). Conclusions: The efficacy of MA and SS is comparable. The intravenous administration of these compounds did not produce immediate reactions, but it was associated with unusual clinical and laboratory abnormalities. [ABSTRACT FROM AUTHOR]

Cutaneous and mucosal leishmaniasis, caused in South America by Leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [Sb(V)]). Treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. Many isolates of L. braziliensis (>25%) contain a double-stranded RNA virus named Leishmaniavirus 1 (LRV1), which has also been reported in Leishmania guyanensis, for which an association with increased pathology, metastasis, and parasite replication was found in murine models. Here we probed the relationship of LRV1 to drug treatment success and disease in 97 L. braziliensis-infected patients from Peru and Bolivia. In vitro cultures were established, parasites were typed as L. braziliensis, and the presence of LRV1 was determined by reverse transcription-polymerase chain reaction, followed by sequence analysis. LRV1 was associated significantly with an increased risk of treatment failure (odds ratio, 3.99; P = .04). There was no significant association with intrinsic Sb(V) resistance among parasites, suggesting that treatment failure arises from LRV1-mediated effects on host metabolism and/or parasite survival. The association of LRV1 with clinical drug treatment failure could serve to guide more-effective treatment of tegumentary disease caused by L. braziliensis. [ABSTRACT FROM AUTHOR]

Thermotherapy is an accepted alternative therapy for new-world cutaneous leishmaniasis, but current heat-delivery modalities are too costly to be made widely available to endemic populations. We adapted a low-cost heat pack named the HECT-CL device that delivers safe, reliable, and renewable conduction heat. 25 patients with cutaneous leishmaniasis completed treatment with the device at an initial temperature of 52°C±2°C for 3 minutes to each lesion, repeated daily for 7 days, and were followed up for 6 months by direct observation. The overall definitive clinical cure rate was 60%. Concurrently, 13 patients meeting minimally significant exclusion criteria received identical compassionate use treatment with a cumulative definitive cure rate of 68.4%, 75% for those who had experienced CL relapse after prior antimonial treatment. Therapy was well tolerated. Reversible second-degree burns occurred in two patients and no bacterial super-infections were observed. HECT-CL is a promising treatment and deserves further study to verify its safety and efficacy as adjuvant and mono- therapy. [ABSTRACT FROM AUTHOR]

Background: Increased rates for failure in leishmaniasis antimony treatment have been recently recognized worldwide. Although several risk factors have been identified there is no clinical score to predict antimony therapy failure of cutaneous leishmaniasis. Methods: A case control study was conducted in Peru from 2001 to 2004. 171 patients were treated with pentavalent antimony and followed up to at least 6 months to determine cure or failure. Only patients with ulcerative cutaneous leishmaniasis (N = 87) were considered for data analysis. Epidemiological, demographical, clinical and laboratory data were analyzed to identify risk factors for treatment failure. Two prognostic scores for antimonial treatment failure were tested for sensitivity and specificity to predict antimony therapy failure by comparison with treatment outcome. Results: Among 87 antimony-treated patients, 18 (21%) failed the treatment and 69 (79%) were cured. A novel risk factor for treatment failure was identified: presence of concomitant distant lesions. Patients presenting concomitant-distant lesions showed a 30.5-fold increase in the risk of treatment failure compared to other patients. The best prognostic score for antimonial treatment failure showed a sensitivity of 77.78% and specificity of 95.52% to predict antimony therapy failure. Conclusions: A prognostic score including a novel risk factor was able to predict antimonial treatment failure in cutaneous leishmaniasis with high specificity and sensitivity. This prognostic score presents practical advantages as it relies on clinical and epidemiological characteristics, easily obtained by physicians or health workers, and makes it a promising clinical tool that needs to be validated before their use for developing countries. Author Summary: The manuscript is relevant because of the finding of a new risk factor for chemotherapy failure and the development of a prognosis score for cutaneous leishmaniasis. The proportion of patients that have multiple lesions in American Tegumentary Leishmaniasis (ATL) is considerable. Publications and our experience permit to estimate that they represent around 20% of the affected population from the Amazon basin with cutaneous lesions. In addition, about 1/3 of them would correspond to the concomitant distant lesions category, the novel risk factor identified with a very high odds ratio (20–30) associated. Such numbers merit study of concomitant distant ulcers category on its own, not only because of clinical management implications, but also to search for factors that are contributing to chemotherapy failure. Finally, the simple equation proposed in the manuscript can be easily adapted to smart phone technologies. Similar prognosis equations are scarce for other pathologies and do not exist for Cutaneous Leishmaniasis at all. The simplicity of this tool should be followed by subsequent epidemiologic studies in other ATL endemic regions. [ABSTRACT FROM AUTHOR]

Background: Traditional methods of diagnosing mucosal leishmaniasis (ML), such as biopsy with histopathology, are insensitive and require collection of an invasive diagnostic specimen. Methods: We compared standard invasive procedures including biopsy histopathology, biopsy PCR, and leishmanin skin test (LST) to a novel, non-invasive, cytology-brush based PCR for the diagnosis of ML in Lima, Peru. Consensus reference standard was 2/4 tests positive, and outcome measures were sensitivity and specificity. Leishmania species identification was performed by PCR-based assays of positive specimens. Results: Twenty-eight patients were enrolled, 23 of whom fulfilled criteria for a diagnosis of ML. Sensitivity and specificity of biopsy with histopathology were 21.7% [95% CI 4.9-38.5%] and 100%; 69.6% [95% CI 50.8-88.4%] and 100% for LST; 95.7% [95% CI 87.4-100%] and 100% for biopsy PCR; and 95.7% [95% CI 87.4-100%] and 90% [95% CI 71.4-100%] for cytology brush PCR using both CervisoftH and HistobrushH cervical cytology brushes. Represented species identified by PCR-RFLP included: L. (V). braziliensis (n = 4), and L. (V). peruviana (n = 3). Conclusions: Use of commercial grade cytology brush PCR for diagnosis of ML is sensitive, rapid, well tolerated, and carries none of the risks of invasive diagnostic procedures such as biopsy. Further optimization is required for adequate species identification. Further evaluation of this method in field and other settings is warranted. [ABSTRACT FROM AUTHOR]

Background. Traditional detection of Leishmania from ulcers involves collection of invasive specimens that cause discomfort, require technical expertise, and carry risks of invasive procedures. We compared traditional diagnostic methods with a molecular noninvasive filter paper-based method for the diagnosis of cutaneous leishmaniasis. Methods. Consecutive patients presenting to the Leishmania Clinic at Hospital Nacional Cayetano Heredia were enrolled. Polymerase chain reaction (PCR) was performed on lesion scrapings, aspirates, and filter paper impressions. The reference standard was any 2 of 5 tests positive: smear, aspirate culture, invasive-specimen PCR (scrapings and aspirates), filter paper PCR, and leishmanin skin test. Outcome measures were sensitivity and specificity. Leishmania speciation was performed by PCR--restriction fragment length polymorphism (RFLP) of positive specimens. Results. Forty-five patients with 66 lesions were enrolled. Of 52 lesions diagnosed as cutaneous leishmaniasis, 50 were positive by PCR of invasive specimens versus 48 by PCR of filter papers (P = .930). Sensitivity and specificity of PCR on invasively obtained specimens were 94.2% (95% confidence interval [CI], 87.9%-100%) and 92.9% (95% CI, 79.4%-100%). Sensitivity and specificity of filter paper PCR were 92.3% (95% CI, 85.1%-99.5%) and 100%. Culture, smear, and leishmanin skin test all had inferior sensitivities, compared with PCR of invasive or noninvasive specimens (P < .001). Of 50 specimens positive by PCR, 19 had sufficient DNA for PCR-RFLP analysis. Conclusions. Filter paper PCR constitutes a sensitive and specific alternative to traditional diagnostic assays. This novel, rapid, well-tolerated method has the potential for widespread use in the field and in pediatric populations where traditional specimen collection is most difficult to perform, and can potentially be used for rapid species identification. [ABSTRACT FROM AUTHOR]

Leishmania species of the subgenus Viannia and especially Leishmania braziliensis are responsible for a large proportion of New World leishmaniasis cases. The reproductive mode of Leishmania species has often been assumed to be predominantly clonal, but remains unsettled. We have investigated the genetic polymorphism at 12 microsatellite loci on 124 human strains of Leishmania braziliensis from 2 countries, Peru and Bolivia. There is substantial genetic diversity, with an average of 12.4 ± 4.4 alleles per locus. There is linkage disequilibrium at a genome-wide scale, as well as a substantial heterozygote deficit (more than 50% the expected value from Hardy-Weinberg equilibrium), which indicates high levels of inbreeding. These observations are inconsistent with a strictly clonal model of reproduction, which implies excess heterozygosity. Moreover, there is large genetic heterogeneity between populations within countries (Wahlund effect), which evinces a strong population structure at a microgeographic scale. Our findings are compatible with the existence of population foci at a microgeographic scale, where clonality alternates with sexuality of an endogamic nature, with possible occasional recombination events between individuals of different genotypes. These findings provide key clues on the ecology and transmission patterns of Leishmania parasites. [ABSTRACT FROM AUTHOR]

Accurate identification of Leishmania species is important for monitoring clinical outcome, adequately targeting treatment, and evaluation of epidemiological risk in tegumentary leishmaniasis. This is especially the case in regions where several species coexist and for travel medicine where the geographical source of infection is not always obvious. Species identification presently depends on parasite isolation, which is not very sensitive and not necessarily representative of parasites actually present in human tissues. We evaluated a polymerase chain reaction (PCR) assay combining amplification of the gp63 genes and restriction fragment length polymorphism (RFLP) analysis (gp63 PCR-RFLP) for direct Leishmania species-identification in tissues collected from Peruvian patients in 1999. By comparison with a kinetoplast DNA-based PCR, our PCR assay showed a detection sensitivity of 85%. Three species were engountered among patient samples, Leishmania (Viannia) braziliensis, L. (V.) peruviana and L. (V.) guyanensis, and their frequency and geographical distribution corresponded to earlier epidemiological studies of leishmaniasis in Peru. However, unexpected results raised questions about (i) the contribution of human migration to the emergence of new foci of given species, (ii) the pathogenicity of some species, and (iii) the frequency of mixed or hybrid infections. [Copyright &y& Elsevier]