The Leishmania parasite resides and replicates within host macrophages during visceral leishmaniasis (VL). This study aimed to evaluate neopterin, a marker of macrophage activation, as possible pharmacodynamic biomarker to monitor VL treatment response and to predict long-term clinical relapse of VL. Following informed consent, 497 plasma samples were collected from East-African VL patients receiving a 28-day miltefosine monotherapy (48 patients) or 11-day combination therapy of miltefosine and liposomal amphotericin B (L-AMB, 48 patients). Neopterin was quantified with ELISA. Values are reported as median (inter-quartile range). Baseline neopterin concentrations were elevated in all VL patients at 98.8 (63.9-135) nmol/L compared to reported levels for healthy controls (<10 nmol/L). During the first treatment week, concentrations remained stable in monotherapy patients (p = 0.807), but decreased two-fold compared to baseline in the combination therapy patients (p < 0.01). In the combination therapy arm, neopterin concentrations increased significantly 1 day after L-AMB infusion compared to baseline for cured patients [137 (98.5-197) nmol/L, p < 0.01], but not for relapsing patients [84.4 (68.9-106) nmol/L, p = 0.96]. The neopterin parameter with the highest predictive power for VL relapse was a higher than 8% neopterin concentration increase between end of treatment and day 60 follow-up (ROC AUC 0.84), with a 93% sensitivity and 65% specificity. In conclusion, the identified neopterin parameter could be a potentially useful surrogate endpoint to identify patients in clinical trials at risk of relapse earlier during follow-up, possibly in a panel of biomarkers to increase its specificity.

Amphotericin B (AMB) is a polyene macrolide antibiotic used for treating invasive fungal infections. Liposomal AMB (L-AMB) is a lipid dosage form which reduces the side effects and toxicity of the drug. The quantitation of free AMB (F-AMB) and L-AMB in vivo is important to monitor quality control of the liposomal formulation and to ensure its safety during clinical use. In this study, an original strategy was developed to separately determine F-AMB and L-AMB in rat plasma using LC-MS/MS. F-AMB was analyzed after separation by solid phase extraction, total AMB (T-AMB) was determined after protein precipitation and L-AMB was determined by difference. The method was fully validated. Calibration curves were linear in the ranges 0.7-120 μg/mL for T-AMB and 0.2-20 μg/mL for F-AMB. Accuracy and precision results were within acceptable variability limits, recoveries were consistent and reproducible, matrix effects were insignificant and analytes were stable under all the storage conditions tested. The method was successfully applied to a pharmacokinetic study in rats administered a single intravenous 6 mg/kg dose of L-AMB. The method will allow further clinical studies of L-AMB and provide useful technical support for the assay of other liposomal drug formulations.

Coinfection with human visceral leishmaniasis (HVL) and human immunodeficiency virus (HIV) has become an emerging public health problem in several parts of the world, with high morbidity and mortality rates. A systematic review was carried out in the literature available in PubMed, Scielo and Lilacs related to HVL associated with HIV coinfection, seeking to analyze epidemiological, clinical and laboratory aspects. Of the 265 articles found, 15 articles were included in the qualitative analysis, which referred to the results of HVL treatment in patients coinfected with HIV. In the published articles between 2007 and 2015, 1171 cases of HVL/HIV coinfection were identified, 86% males, average age 34 years, liposomal amphotericin B was the most commonly used drug, cure rates 68 and 20% relapses and 19% deaths, five different countries, bone marrow was used in 10/15 manuscripts. HVL/HIV coinfection is a major challenge for public health, mainly due to the difficulty in establishing an accurate diagnosis, low response to treatment with high relapse rates and evolution to death. In addition, these two pathogens act concomitantly for the depletion of the immune system, contributing to worsening the clinical picture of these diseases, which requires effective surveillance and epidemiological control measures.

Background Visceral leishmaniasis (VL) is endemic to the Mediterranean basin. In children, VL often presents with non-specific symptoms and can be life-threatening without proper treatment. Aim To describe the epidemiological and clinical features of pediatric VL in children in Alicante, Spain. Methods The study included all paediatric (<15 years) cases admitted to three hospitals in the province of Alicante from May 1992 to May 2015 with diagnosis of VL (detection was either by anti-Leishmania antibodies in serology or Leishmania in blood and/or bone marrow aspirates). Results There were 38 cases of pediatric VL (18 aged <24 months, 15 aged 24-59 months and 5 aged ≥5 years). The main symptoms were fever (97.4%), followed by pallor (75.0%) and loss of appetite (46.4%). Eighty-seven per cent of patients were anaemic (haemoglobin < 9 g/dL), 73.7% had neutropenia and 68.4% had thrombocytopenia. Before 2004, 92.3% of patients were treated with meglumine antimoniate (MA) and 7.7% with liposomal amphotericin B (LAmB); after 2004, 84% were treated with LAmB and just one (16%) with MA (p < 0.001). LAmB performed better than MA in terms of mean treatment length (7.4 days vs 25.9 days, p < 0.001), time to becoming afebrile (1.7 vs 13.7 days, p < 0.001), and length of hospital stay (10.9 vs 19.4 days, p = 0.001). Conclusion Paediatric VL in Alicante mainly affects children under five. Children aged ≤24 months present with a lower haemoglobin and white blood cell count. Treatment with LAmB reduces treatment length, time to becoming afebrile and length of hospital stay.

Visceral Leishmaniasis (VL), caused by the protozoan parasite Leishmania donovani, is a potentially fatal disease. The only orally bioavailable drug miltefosine is toxic and the effective liposomal Amphotericin B (AmBisome) is limited by its prohibitive cost and requirement for parenteral administration. Therefore, finding a new potential drug candidate and an alternative delivery system is imperative. We report that Betulinic acid (BA), a pentacyclic triterpenoid from Betula alba bark, was loaded onto uniformly spherical PLGA nanoparticles (BANPs; diameter 187.5 ± 5.60 nm) coated with Lactoferrin (Lf-BANPs). The amastigotes count in macrophages was more effectively reduced by Lf-BANP than BA and BANP. Lf-BANPs reduced the pro-parasitic, anti-inflammatory cytokine IL-10, but increased nitric oxide (NO), production in L. donovani-infected macrophages indicating that Lf-BANP possesses a significant anti-leishmanial activity.