A Double-blind, Randomized Trial to Evaluate Miltefosine and Topical Granulocyte Macrophage Colony-stimulating Factor in the Treatment of Cutaneous Leishmaniasis Caused by Leishmania braziliensis in Brazil.

BACKGROUND: The treatment of cutaneous leishmaniasis (CL) in Brazil using pentavalent antimony (Sbv) is associated with a high rate of failure. Miltefosine has proven efficacy for CL caused by L. braziliensis, with a cure rate (CR) of 75%. A combined treatment with granulocyte macrophage colony-stimulating factor (GM-CSF) and miltefosine could increase CR and decrease healing time. METHODS: A randomized, double-blind clinical trial to evaluate the efficacy of miltefosine combined with topical GM-CSF (M + GM) vs miltefosine and placebo (M + P) vs Sbv in 133 patients with CL caused by L. braziliensis in Bahia, Brazil. RESULTS: The final CR at 180 days after the initiation of treatment was 44.4% in the Sbv group, 76.6% in the M + P group (P = .003 vs Sbv), and 75.6% in the M + GM group (P = .004 vs Sbv). The median healing time for cure was 102 days for the Sbv group and 60 days for both miltefosine groups (P = .0009). During the 6-month follow-up period, 4 relapses were documented: 1 in the Sbv group, 1 in the M + P group, and 2 in the M + GM group. Mild adverse events occurred in 65% of patients from the Sbv group, 76% and 79% from the M + P and M + GM groups respectively. CONCLUSIONS: Miltefosine is more effective than Sbv for the treatment of CL caused by L. braziliensis in Brazil and accelerates the healing time. Association with GM-CSF does not improve therapeutic outcome. CLINICAL TRIALS REGISTRATION: NCT03023111.

Diabetes Modifies the Clinic Presentation of Cutaneous Leishmaniasis.

BACKGROUND: Cutaneous leishmaniasis (CL) caused by L. braziliensis is characterized by 1 or multiple well-limited ulcerated lesions. Diabetes mellitus (DM) impairs neutrophil and monocyte function, and there is a report of vegetative lesions in a patient with both diseases in Morocco. Here we evaluate the influence of DM on clinical manifestations, immune response, and in the treatment of CL. METHODS: The participants were 36 DM patients with CL and 36 patients with CL without DM, matched by age and gender. The diagnosis of CL was performed by documentation of DNA of L. braziliensis by polymerase chain reaction in the lesion biopsy and histopathologic findings. All patients were treated with Glucantime (Sanofi-Aventis) 20 mg/kg of weight per day for 20 days. RESULTS: There was no difference in the majority of the clinical variables between the groups, and the cure rate in patients with CL and DM (67%) was similar to that observed in CL patients (56%; P ˃ .05). The most important finding was the documentation that 36% of the patients with DM and CL had atypical cutaneous lesions characterized by large superficial ulcers without defined borders. High levels of interferon-γ, tumor necrosis facor, and interleukin-1ß were detected in the supernatants of mononuclear cells stimulated with Leishmania antigen in patients with DM and atypical CL. Moreover, while cure was observed in only 33% of the patients with DM and atypical CL lesions, it was observed in 85% of patients with typical lesions (P < .05). CONCLUSIONS: DM modifies the clinical presentation of CL, enhances pro-inflammatory cytokine production, and impairs response to antimony therapy.

Early Suppression of Macrophage Gene Expression by Leishmania braziliensis.

Leishmania braziliensis is an intracellular parasite that resides mostly in macrophages. Both the parasite genome and the clinical disease manifestations show considerable polymorphism. Clinical syndromes caused by L. braziliensis include localized cutaneous (CL), mucosal (ML), and disseminated leishmaniasis (DL). Our prior studies showed that genetically distinct L. braziliensis clades associate with different clinical types. Herein, we hypothesized that: (1) L. braziliensis induces changes in macrophage gene expression that facilitates infection; (2) infection of macrophages with strains associated with CL (clade B), ML (clade C), or DL (clade A) will differentially affect host cell gene expression, reflecting their different pathogenic mechanisms; and (3) differences between the strains will be reflected by differences in macrophage gene expression after initial exposure to the parasite. Human monocyte derived macrophages were infected with L. braziliensis isolates from clades A, B, or C. Patterns of gene expression were compared using Affymetrix DNA microarrays. Many transcripts were significantly decreased by infection with all isolates. The most dramatically decreased transcripts encoded proteins involved in signaling pathways, apoptosis, or mitochondrial oxidative phosphorylation. Some transcripts encoding stress response proteins were up-regulated. Differences between L. braziliensis clades were observed in the magnitude of change, rather than the identity of transcripts. Isolates from subjects with metastatic disease (ML and DL) induced a greater magnitude of change than isolates from CL. We conclude that L. braziliensis enhances its intracellular survival by inhibiting macrophage pathways leading to microbicidal activity. Parasite strains destined for dissemination may exert a more profound suppression than less invasive L. braziliensis strains that remain near the cutaneous site of inoculation.

A Potential Role for Mononuclear Phagocytes in Cutaneous Ulcer Development in Human Immunodeficiency Virus-Leishmania braziliensis Coinfection.

Skin ulcer development in cutaneous leishmaniasis due to Leishmania braziliensis infection is associated with a mononuclear cell infiltrate and high levels of tumor necrosis factor (TNF). Herein, we show that despite the absence of Leishmania-driven TNF, a cutaneous leishmaniasis patient with acquired immunodeficiency syndrome developed a skin ulcer. The presence of mononuclear phagocytes and high levels of TNF, chemokine (C-C motif) ligand 2 (CCL2), and metalloproteinase-9 in tissue are identified as potential contributors to immunopathology observed in L. braziliensis-infected patients.

Association of treatment of American cutaneous leishmaniasis prior to ulcer development with high rate of failure in northeastern Brazil.

Cure rates for American cutaneous leishmaniasis (ACL) range between 60% and 90%. Early evidence suggests lower cure rates for early ACL before the development of the ulceration. We evaluated risk factors for treatment failure in patients with early and classic ulcerative ACL. Patients (n = 136) were 13-60 years of age and had lesions with a duration of 15-90-days. Patients were treated with antimony (20 mg/kg/day for 20 days). The primary outcome was lesion cure by 90 days without recurrence. Patients with early ACL (n = 16) had papules, nodules, plaques, or superficial ulcerations with less than 30 days of illness. Patients with classic ulcerative ACL (n = 120) had ulcerated classic lesions, longer duration, larger lesions, and higher levels of interferon-gamma and tumor necrosis factor-alpha (P < or = 0.01 for all comparisons). Ulcerated lesions were associated with a lower treatment failure rate compared with early ACL (25.8% versus 75.0%; P < 0.001). Early treatment of ACL does not prevent lesion ulceration and is associated with higher rates of treatment failure.

Oral pentoxifylline combined with pentavalent antimony: a randomized trial for mucosal leishmaniasis.

BACKGROUND: Mucosal leishmaniasis is associated with intense tissue damage and high tumor necrosis factor-alpha production. Therapeutic failure occurs in up to 42% of cases; patients who experience treatment failure will require >1 pentavalent antimony (Sb(v)) course or alternative drugs to achieve a cure. We previously showed that an inhibitor of tumor necrosis factor-alpha (pentoxifylline) combined with Sb(v) cured 90% patients refractory to monotherapy with Sb(v). METHODS: A double-blind, placebo-controlled trial involving 23 patients with mucosal leishmaniasis evaluated the efficacy of pentoxifylline when administered in association with Sb(v), compared with Sb(v) treatment alone. Eleven patients were randomized to receive Sb(v) plus oral pentoxifylline for 30 days, and 12 patients received Sb(v) plus oral placebo. The criterion for cure was a complete healing of lesions. RESULTS: All patients in the pentoxifylline group experienced a cure with 1 course of Sb(v), whereas 5 (41.6%) of 12 patients in the placebo group required a second course of Sb(v) (P=.037). The healing time +/- standard deviation in the pentoxifylline group was 83+/-36 days, compared with 145+/-99 days in the placebo group (P=.049). No relapses were documented in either group at the 2-year follow-up visit. CONCLUSIONS: The addition of pentoxifylline to Sb(v) in mucosal leishmaniasis reduces the healing time significantly and prevents the need for further courses of Sb(v).