Cutaneous leishmaniasis treatment and therapeutic outcomes in special populations: A collaborative retrospective study.

BACKGROUND: Treatment guidance for children and older adult patients affected by cutaneous leishmaniasis (CL) is unclear due to limited representation of these groups in clinical trials. METHODS: We conducted a collaborative retrospective study to describe the effectiveness and safety of antileishmanial treatments in children ≤ 10 and adults ≥ 60 years of age, treated between 2014 and 2018 in ten CL referral centers in Latin America. RESULTS: 2,037 clinical records were assessed for eligibility. Of them, the main reason for non-inclusion was lack of data on treatment follow-up and therapeutic response (182/242, 75% of children and 179/468, 38% of adults). Data on 1,325 eligible CL patients (736 children and 589 older adults) were analyzed. In both age groups, disease presentation was mild, with a median number of lesions of one (IQR: 1-2) and median lesion diameter of less than 3 cm. Less than 50% of the patients had data for two or more follow-up visits post-treatment (being only 28% in pediatric patients). Systemic antimonials were the most common monotherapy regimen in both age groups (590/736, 80.2% of children and 308/589, 52.3% of older adults) with overall cure rates of 54.6% (95% CI: 50.5-58.6%) and 68.2% (95% CI: 62.6-73.4%), respectively. Other treatments used include miltefosine, amphotericin B, intralesional antimonials, and pentamidine. Adverse reactions related to the main treatment were experienced in 11.9% (86/722) of children versus 38.4% (206/537) of older adults. Most adverse reactions were of mild intensity. CONCLUSION: Our findings support the need for greater availability and use of alternatives to systemic antimonials, particularly local therapies, and development of strategies to improve patient follow-up across the region, with special attention to pediatric populations.

A phase II multicenter randomized study to evaluate the safety and efficacy of combining thermotherapy and a short course of miltefosine for the treatment of uncomplicated cutaneous leishmaniasis in the New World.

BACKGROUND: Systemic pentavalent antimonials, mainly meglumine antimoniate, continue to be the first-choice drugs for treatment of cutaneous leishmaniasis (CL) despite their toxicity, difficulty of administration and high cost. In the search for therapeutic alternatives, combining two treatment interventions has emerged as a potential alternative to either reduce the use of antimonials with the associated toxicities, or to increase efficacy. Here, we report the results of a recently completed trial assessing the efficacy and safety of a combination of thermotherapy (TT) plus a short course of miltefosine (MLT) for the treatment of uncomplicated CL in Colombia and Peru. METHODS: A multicenter, randomized, evaluator-blinded, phase II, controled clinical trial was conducted. Adult volunteers with a parasitologically confirmed diagnosis of uncomplicated CL were randomly allocated to receive either a single session of TT or a combination of TT plus a short course of MLT (3 weeks). Therapeutic response outcomes and safety were assessed. RESULTS: 130 subjects were included in the study, of whom 64 were randomly assigned to the TT arm and 66 to the TT + MLT arm. Cure at 3 months' follow-up was achieved in 57.8% (n = 37) and 80.3% (n = 53) in the TT and TT + MLT groups, respectively, in the intention to treat analysis. The TT + MLT regimen was better that TT alone (p = 0.0055). The presence of vesicles at the site of heat application was the most common adverse event reported associated with the use of TT; while vomiting (31.8%) and elevation of liver enzymes (28.8%) were the most frequent adverse events reported associated with the use of MLT. CONCLUSION: The combination of TT plus a short course of MLT was shown to be significantly better than TT alone for the treatment of uncomplicated CL in the New World. TRIAL REGISTRATION: Registered in clinicaltrials.gov NCT02687971.

Leishmania RNA virus-1 is similarly detected among metastatic and non-metastatic phenotypes in a prospective cohort of American Tegumentary Leishmaniasis.

American Tegumentary Leishmaniasis (ATL) is an endemic and neglected disease of South America. Here, mucosal leishmaniasis (ML) disproportionately affects up to 20% of subjects with current or previous localised cutaneous leishmaniasis (LCL). Preclinical and clinical reports have implicated the Leishmania RNA virus-1 (LRV1) as a possible determinant of progression to ML and other severe manifestations such as extensive cutaneous and mucosal disease and treatment failure and relapse. However, these associations were not consistently found in other observational studies and are exclusively based on cross-sectional designs. In the present study, 56 subjects with confirmed ATL were assessed and followed out for 24-months post-treatment. Lesion biopsy specimens were processed for molecular detection and quantification of Leishmania parasites, species identification, and LRV1 detection. Among individuals presenting LRV1 positive lesions, 40% harboured metastatic phenotypes; comparatively 58.1% of patients with LRV1 negative lesions harboured metastatic phenotypes (p = 0.299). We found treatment failure (p = 0.575) and frequency of severe metastatic phenotypes (p = 0.667) to be similarly independent of the LRV1. Parasite loads did not differ according to the LRV1 status (p = 0.330), nor did Leishmanin skin induration size (p = 0.907) or histopathologic patterns (p = 0.780). This study did not find clinical, parasitological, or immunological evidence supporting the hypothesis that LRV1 is a significant determinant of the pathobiology of ATL.

Innate immune response: ally or enemy in cutaneous leishmaniasis?

Cutaneous leishmaniasis (CL) is an infectious and neglected disease caused by parasites of the genus Leishmania, which produces a wide spectrum of cutaneous manifestations. CL research has shown that the innate immune activity of cells such as neutrophils, natural killers, macrophages, dendritic cells and the complement system are capable of controlling this infection. However, Leishmania can also modulate the immune activity of these cells to promote its own survival and proliferation at the intracellular level. This review discusses the role of the innate immune response in the control and spread of this infection.

Polymerase chain reaction detection of Leishmania kDNA from the urine of Peruvian patients with cutaneous and mucocutaneous leishmaniasis.

We hypothesized that Leishmania kDNA may be present in urine of patients with cutaneous leishmaniasis (CL). Urine samples and standard diagnostic specimens were collected from patients with skin lesions. kDNA polymerase chain reaction (PCR) was performed on samples from patients and 10 healthy volunteers from non-endemic areas. Eighty-six of 108 patients were diagnosed with CL and 18 (21%) had detectable Leishmania Viannia kDNA in the urine. Sensitivity and specificity were 20.9% (95% confidence interval [CI] 12.3-29.5%) and 100%. Six of 8 patients with mucocutaneous involvement had detectable kDNA in urine versus 12 of 78 patients with isolated cutaneous disease (P < 0.001). L. (V.) braziliensis (N = 3), L. (V.) guyanensis (N = 6), and L. (V.) peruviana (N = 3) were identified from urine. No healthy volunteer or patient with an alternate diagnosis had detectable kDNA in urine. Sensitivity of urine PCR is sub-optimal for diagnosis. On the basis of these preliminary data in a small number of patients, detectable kDNA in urine may identify less localized forms of infection and inform treatment decisions.

Diagnostic performance of filter paper lesion impression PCR for secondarily infected ulcers and nonulcerative lesions caused by cutaneous leishmaniasis.

We compared traditional cutaneous leishmaniasis diagnostic methods to filter paper lesion impression (FPLI) PCR for secondarily infected ulcers and nonulcerative lesions. The sensitivity and specificity of FPLI PCR for secondarily infected lesions (n = 8) were 100%. In primarily nonulcerative lesions (n = 15), the sensitivity of FPLI PCR was inferior to that of pooled-invasive-specimen PCR (72.7% versus 100%) (P = 0.10). FPLI PCR is sensitive, specific, and unlike invasive procedures, can be used in secondarily infected ulcers. Invasive specimen collection is superior in nonulcerative lesions.

Detection and species identification of Leishmania DNA from filter paper lesion impressions for patients with American cutaneous leishmaniasis.

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.