ABSTRACT
BACKGROUND: Leishmaniasis is an infectious disease caused by Leishmania parasites. A Th1 immune response is necessary in the acute phase to control the pathogen. The triggering receptor expressed on myeloid cells (TREM)-1 is a potent amplifier of inflammation. Our aim is to identify whether the TREM1 variant rs2234237 A/T (Thr25Ser) is associated with the disease development of cutaneous leishmaniasis (CL) in Leishmania guyanensis-infected individuals. The effects of the rs2234237 genotypes on plasma cytokines IL-1ß, IL-6, IL-8, IL-10, MCP-1 and TNF-α are also investigated. METHODS: 838 patients with CL and 818 healthy controls (HCs) living in the same endemic areas were genotyped by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism. Plasma cytokines were assayed in 400 patients with CL and 400 HCs using the BioPlex assay. RESULTS: The genotypes' and alleles' frequencies were similar in both patients with CL (AA = 618, 74%; AT = 202, 24%; TT = 18, 2%) and in HCs (AA = 580, 71%; AT = 220, 27%; TT = 18, 2%). Rs2234237 showed a modest effect on plasma IL-10 that disappeared when correction of the p-value was applied. Plasma IL-10 by rs2234237 genotypes were (mean ± SEM; AA = 2.91 pg/mL ± 0.14; AT = 2.35 pg/mL ± 0.12; TT = 3.14 pg/mL ± 0.56; p = 0.05). CONCLUSION: The TREM1 rs2234237 (Thr25Ser) seems to have no influence on the susceptibility or resistance to L. guyanensis infections.
ABSTRACT
BACKGROUND: American Cutaneous Leishmaniasis (ACL), a vector borne disease, is caused by various species of Leishmania and in the Amazonas, Leishmania guyanensis is predominant. The recommended drugs for treatment of cutaneous leishmaniasis (CL) in Brazil are pentavalent antimonials, pentamidine isethionate (PI) and amphotericin B. Pentamidine was initially used as metanolsulfonate or mesylate (Lomidine) at a dose of 4 mg/kg/daily, containing 2.3mg of base. This drug was withdrawn from the market in the eighties, and currently is available as PI. The PI dose required to achieve an equivalent dose of pentamidine base is 7 mg/kg, rather than the 4 mg/kg that is currently recommended in Brazil. OBJECTIVES: The aim of this study was to evaluate the efficacy and safety of PI in a single dose, two or three doses of 7 mg/kg body weight, intramuscularly, with an interval of seven days between each dose. MATERIALS AND METHODS: This study was conducted as a controlled, randomized, open-label clinical trial for a total number of 159 patients with CL. Individuals aged 16-64 years with one to six lesions of confirmed CL based on amastigotes visualization in direct examination of Giemsa stained of dermal scraping from the border of the lesion with no previous treatment for CL and no abnormal values for liver enzymes were eligible to participate in the study. Patients with history of diabetes, cardiac, renal, and hepatic disease as well as pregnant women were excluded. Cure was defined as complete healing in the diameters of the ulcers and lesions skin six months after the end of the treatment. RESULTS: From November 2013 to December 2015, 159 patients were screened and allocated in three groups for treatment with PI: i) 53 patients were treated with a single dose intramuscularly injection of 7 mg/kg body weight; ii) 53 received two doses of 7 mg/kg within an interval of seven days; and iii) 53 were treated with three doses of 7mg/kg with an interval of seven days between each dose. In 120 patients, L. guyanensis was identified. A cure rate of 45%, 81.1% and 96.2% were observed in the first, second and third group, respectively. The cure in the three PI dose group was higher compared to the single-dose (p<0.0001) and two-dose groups (p = 0.03). No serious adverse events occurred. CONCLUSION: The present study shows that PI is a safe drug and its efficacy varied with the number of doses. The administration of PI in patients with ACL, predominantly caused by L. guyanensis, was mostly efficient in three or two doses of 7 mg/kg. TRIAL REGISTRATION: ClinicalTrials.gov NCT02919605.