T-cell immune responses in patients with cutaneous leishmaniasis (CL) and mucosal leishmaniasis (ML)were studied during the active disease, at the end of therapy, and 1 to 17 years posttherapy (long-term follow-up). Lymphocyte proliferative responses, phenotypic characterization of CD4 ؉ and CD8 ؉ Leishmaniareactive T cells, and cytokine production were assayed. Patients with active ML and CL showed higher proportions of CD4 ؉ than CD8 ؉ T cells. In CL, the healing process was associated with a decrease of CD4؉ and an increase of CD8 ؉ , leading to similar CD4 ؉ and CD8 ؉ proportions. This pattern was only seen in ML after long-term therapy. Long-term follow-up of patients with CL showed a positive CD4؉ /CD8 ؉ ratio as observed during the active disease, although the percentages of these T cell subsets were significantly lower. Patients with CL did not show significant differences between gamma interferon (IFN-␥) and interleukin-5 (IL-5) production during the period of study. Patients with active ML presented higher IFN-␥ and IL-5 levels compared to patients with active CL. IL-4 was only detected during active disease. Patients long term after cure from ML showed increasing production of IFN-␥, significant decrease of IL-5, and no IL-4 production. Two apparently beneficial immunological parameters were detected in tegumentary leishmaniasis: (i) decreasing proportions of CD4 ؉ Leishmania-reactive T cells in the absence of IL-4 production associated with cure of CL and ML and (ii) decreasing levels of IL-5 long after cure, better detected in patients with ML. The observed T-cell responses maintained for a long period in healed patients could be relevant for immunoprotection against reinfection and used as a parameter for determining the prognosis of patients and selecting future vaccine preparations.
Abstract. We evaluated the effectiveness and safety of intralesional meglumine antimoniate (MA) in 24 not submitted to previous treatment patients with cutaneous leishmaniasis (CL) and with contraindication to systemic therapy. Each treatment consisted of one to four intralesional applications of MA at 15-day intervals. Patients' age ranged from 3 to 90 years; fourteen were females. Intralesional treatment in the absence of any relevant toxicity was successful in 20 (83.3%) patients. Three patients required additional treatment with amphotericin B and one required systemic MA. None of the patients developed mucosal lesions when followed up to 60 months. Intralesional MA is an effective and less toxic alternative treatment of patients with CL and contraindication to systemic therapy.American tegumentary leishmaniasis (ATL) affects the skin (cutaneous leishmaniasis, CL) and/or mucous membranes, and is caused by protozoa of the genus Leishmania, transmitted through the bite of sandflies. Research of IPEC; all patients signed a free informed consent form. All patients had a confirmed parasitological diagnosis of CL, had not been previously submitted to TTM, and had contraindication to systemic use of MA. A scale adapted from the Aids Table for Grading the Severity of Adverse Events 7 was used for the evaluation of AE and baseline clinical alterations, where G1 = mild, G2 = moderate, G3 = severe, and G4 = life-threatening. Contraindications to systemic antimonial therapy were 1) presence of baseline clinical alterations corresponding to G3; 2) presence of baseline laboratory alterations corresponding to G2; 3) presence of baseline electrocardiographic alterations corresponding to G3 or G4 (baseline adjusted QT interval [QT adj ] 0.46 ms was considered G3); 4) psychiatric disorders or high probability of low compliance with systemic TTM.AE were monitored by clinical examination, electrocardiogram (EKG), complete blood count and blood biochemistry, before, during, and soon after the end of TTM.The MA was supplied by the Brazilian Ministry of Health (Aventis Pharma, Sã o Paulo, Brazil). Each TTM consisted of 1-4 IL applications of MA, at 15-day intervals. The IL MA was injected subcutaneously until completely infiltrating the base of the lesion. Immediate cure was defined as epithelization up to 90 days after IL TTM. Lesion progression until complete healing was monitored through absence of crusts up to 1 month after epithelization, desquamation up to 3 months, infiltration up to 6 months, and erythema up to 9-12 months, as well as the absence of mucosal lesions. 8 Patients who presented lesion reactivation after TTM were retreated using the same or an alternative regimen; additional IL TTM or other medications were applied according to the presence or absence of EKG changes at the occasion of retreatment and/or therapeutic failure.The nonparametric Mann-Whitney test was used to compare the distribution of continuous variables (lesion area, volume of infiltrated medication per lesion area, etc.) between two groups (pres...
The first line drugs for the treatment of leishmaniasis are antimonial derivatives. Poor clinical response may be credited to factors linked to the host, the drug, or the parasite. We determined the sensitivity of Leishmania sp. promastigotes and amastigotes by counting parasites exposed to increasing concentrations of meglumine antimoniate (Glucantime). Leishmania braziliensis promastigotes were significantly more sensitive than those belonging to other species. The sensitivity of L. braziliensis isolates from patients with unfavorable clinical outcome, such as therapeutic failure or relapse, was significantly lower than those from patients who had clinical cure. Poor clinical response to therapy (therapeutic failure or relapse) was also associated with inadequate antimonial therapy. We also found a significant and positive correlation between promastigotes and intracellular amastigotes with regard to their in vitro susceptibilities to meglumine antimoniate. Our data provide evidence for an association between the sensitivity of promastigotes to antimonials in vitro and clinical response to therapy in American tegumentary leishmaniasis. The high sensitivity of the local L. braziliensis to meglumine antimoniate in vitro provides an explanation for the good clinical response of cutaneous leishmaniasis in the municipality of Rio de Janeiro, Brazil, even when low-dose regimens are employed.
Diffuse cutaneous leishmaniasis (DCL) is characterised by multiple and progressive cutaneous lesions, resistance to chemotherapy and Leishmania-specific T-cell anergy. We report the first autochthonous DCL case and the first human infection with Leishmania amazonensis in Rio de Janeiro State, Brazil, where only L. braziliensis is considered to be the causative agent of cutaneous leishmaniasis. Leishmania amazonensis was identified by multilocus enzyme electrophoresis and PCR-RFLP. Our case was diagnosed as DCL according to clinical, parasitological, histopathological and immunological criteria. These observations indicate that L. amazonensis is increasing its geographical distribution in Brazil, accounting for unusual clinical presentations in new transmission areas.
The present study investigated the diagnostic value of polymerase chain reaction (PCR)
Skin inflammation plays an important role during the healing of American tegumentary leishmaniasis (ATL), the distribution of cells in active lesions may vary according to disease outcome and parasite antigens in ATL scars have already been shown. We evaluated by immunohistochemistry, 18 patients with 1- or 3-year-old scars and the corresponding active lesions and compared them with healthy skin. Small cell clusters in scars organized as in the active lesions spreaded over the fibrotic tissue were detected, as well as close to vessels and cutaneous glands, despite a reduction in the inflammatory process. Analysis of 1-year-old scar tissue showed reduction of NOS2, E-selectin, Ki67, Bcl-2 and Fas expression. However, similar percentages of lymphocytes and macrophages were detected when compared to active lesions. Only 3-year-old scars showed reduction of CD3(+), CD4(+) and CD8(+)T cells, in addition to reduced expression of NOS2, E-selectin, Ki67 and BCl-2. These results suggest that the pattern of cellularity of the inflammatory reaction observed in active lesions changes slowly even after clinical healing. Analysis of 3-year-old scars showed reduction of the inflammatory reaction as demonstrated by decrease in inflammatory cells and in the expression of cell-activity markers, suggesting that the host-parasite balance was only established after that period.
SummaryWhole-cell and soluble extracts of Leishmania promastigotes have both been used as skin test antigens and have also been tested as vaccine candidates. However, the differences in antigenicity between soluble and particulate Leishmania fractions are not known. We evaluated in vitro responses of PBMC from 30 American tegumentary leishmaniasis (ATL) patients and seven noninfected donors to different antigen preparations from Leishmania promastigotes, namely Leishmania amazonensis and L. braziliensis whole-cell extracts, as well as soluble and particulate fractions of L. amazonensis . All Leishmania antigen preparations stimulated significantly higher proliferation and interferon (IFN)-γ γ γ γ production (but not interleukin (IL)-10 production) in PBMC from the leishmaniasis patients than in cells from the control subjects. The L. braziliensis whole-cell extract stimulated significantly higher cell proliferation and IFN-γ γ γ γ production than the L. amazonensis whole-cell extract in the group of patients but not in the control group. This result can be explained by the fact that the patients were infected with L. braziliensis . Again in the group of patients, the PBMC proliferative responses as well as the levels of IFN-γ γ γ γ and IL-10 stimulated by L. amazonensis whole-cell extract were significantly greater than those elicited by the L. amazonensis soluble fraction but were not significantly different from those elicited by the L. amazonensis particulate fraction. We found a higher antigenicity of the particulate fraction as compared to the soluble fraction, what suggests that the antigens present in the particulate fraction account for most of the antigenicity of whole-cell Leishmania promastigote antigen extracts.
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