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Mast cells (MCs) are associated with chronic inflammatory diseases. However, there is no study evaluating the importance of MCs in the mucosal leishmaniasis (ML). The aim of this study was to quantify the most important cytokines associated with mucosal leishmaniasis, before and after disease treatment, correlating with the healing. A cohort of 12 patients with ML was evaluated, and biopsies were taken before and after the treatment. A quantitative estimation of MCs and some cytokines was analysed by density of the labelled cells through immunohistochemistry. The MCs count in the tissue from patients with ML before treatment showed a mean of 29.3 +/- 37.9 cells/mm(2). The MCs count in patients with ML after healing decreased to 14.8 +/- 23.9 cells/mm(2). There was an inverse relation of MCs with IFN-gamma and IL-4 expression (r2 = 29.4 and r2 = 22.3 with P < 0.05). The expression of IL-10 and TNF-alpha was not related with MCs count. MCs decrease after treatment associated with decrease of IL-4 and IFN-gamma. The explanations of cytokine correlation are discussed in the article.

An exacerbated type 1 response to leishmanial antigens is the basis of tissue destruction observed in mucosal leishmaniasis ( ML). After therapy, a persistent production of high levels of inflammatory cytokines can confer a poor prognosis. Herein we investigated whether the clinical conditions defined during the active phase of ML affect the magnitude of long-term anti- Leishmania immune response. Twenty clinically cured ML cases were studied. Peripheral blood mononuclear cells ( PBMC) were cultured with L. braziliensis antigens (Lb- Ag), Toxoplasma gondii antigens (Tg- Ag), concanavalin- A ( Con- A) or medium alone, and the lymphocyte proliferative response and cytokine secretion were quantified. Medical records were reviewed for Montenegro skin test ( MST) during diagnosis, duration of ML disease or time elapsed after clinical cure. The duration of disease was correlated positively with MST ( r = 0·61). Lb- Ag induced interferon ( IFN)-γ was correlated positively with duration of illness ( r = 0·69) as well as the frequency of secreting cells [enzyme-linked immunospot ( ELISPOT)] assay. No association was observed for Tg- Ag or Con-A. Disease duration was correlated negatively with interleukin ( IL)-10 production ( r = −0·76). Moreover, a negative correlation between length of time after clinical cure and TNF levels ( r = −0·94) or the IFN-γ : IL-10 ratio ( r = −0·89) were also seen. We suggest that the magnitude of the IFN-γ inflammatory response triggered by ML can be driven by the time of leishmanial antigens exposition during the active phase of the disease. This pattern could persist even long-term after cure. However, despite IFN-γ levels, the decrease of the TNF and IFN-γ : IL-10 ratio reflects the control of proinflammatory responses achieved by cure of ML, possibly preventing disease relapses. [ABSTRACT FROM AUTHOR]

The Toll-like receptor (TLR) signalling pathway is the first system that defends against Leishmania. After recognising Leishmania as nonself, TLRs trigger NF-κB expression. NF-κB proceeds to the nucleus and promotes the transcription of pro-inflammatory cytokines. TLR9 is thus an important factor in the induction of an effective immune response against Leishmania. We examined the pattern of TLR9 expression in 12 patients with cutaneous leishmaniasis caused by Leishmania braziliensis detected by polymerase chain reaction. Normal skin was analysed as a negative control. TLR9 expression was examined in the dermis and epidermis by immunohistochemical analysis of paraffin-embedded biopsy tissue. TLR9 expression was primarily observed in the granuloma. The protein was detected in a few cells in the dermis. A lower expression level was detected in the epidermis of patients with leishmaniasis when compared with normal skin. The presence of TLR9 in the skin of patients with cutaneous leishmaniasis is associated with granuloma and expressed by macrophages. [ABSTRACT FROM AUTHOR]

Background Mucosal leishmaniasis is caused mainly by Leishmania braziliensis and it occurs months or years after cutaneous lesions. This progressive disease destroys cartilages and osseous structures from face, pharynx and larynx. Objective and methods The aim of this study was to analyse the significance of clinical and epidemiological findings, diagnosis and treatment with the outcome and recurrence of mucosal leishmaniasis through binary logistic regression model from 140 patients with mucosal leishmaniasis from a Brazilian centre. Results The median age of patients was 57.5 and systemic arterial hypertension was the most prevalent secondary disease found in patients with mucosal leishmaniasis (43%). Diabetes, chronic nephropathy and viral hepatitis, allergy and coagulopathy were found in less than 10% of patients. Human immunodeficiency virus (HIV) infection was found in 7 of 140 patients (5%). Rhinorrhea (47%) and epistaxis (75%) were the most common symptoms. N-methyl-glucamine showed a cure rate of 91% and recurrence of 22%. Pentamidine showed a similar rate of cure (91%) and recurrence (25%). Fifteen patients received itraconazole with a cure rate of 73% and recurrence of 18%. Amphotericin B was the drug used in 30 patients with 82% of response with a recurrence rate of 7%. The binary logistic regression analysis demonstrated that systemic arterial hypertension and HIV infection were associated with failure of the treatment ( P < 0.05). Conclusion The current first-line mucosal leishmaniasis therapy shows an adequate cure but later recurrence. HIV infection and systemic arterial hypertension should be investigated before start the treatment of mucosal leishmaniasis. Conflicts of interest The authors are not part of any associations or commercial relationships that might represent conflicts of interest in the writing of this study (e.g. pharmaceutical stock ownership, consultancy, advisory board membership, relevant patents, or research funding). [ABSTRACT FROM AUTHOR]

Lung disease during active human visceral leishmaniasis is frequently reported. As such, studies have associated pulmonary symptoms to interstitial pneumonitis with a mononuclear infiltrate. However, the immune response in this condition has never been described before. The aim of this study was to determine the immunophenotypic pattern and cytokine profile of lung involvement (IPL) in human visceral leishmaniasis. Quantitative methods of analysis were performed using immunohistochemistry, and were compared with a control group of normal lung. Interstitial macrophages and cd8 cells were increased in IPL, and IL-4 as well as TNF-α displayed increased expression when compared to the control group. This inflammatory process with a Th2 pattern, as suggested by increased IL-4 and low IFN-γ expression, is consistent with the immune response in other organs of visceral leishmaniasis. The microenvironment of the immune response in this condition is associated with lung disease in patients with interstitial pneumonitis related to visceral leishmaniasis, increasing the chance of bacterial infection. [ABSTRACT FROM AUTHOR]

Background Comorbidity from tegumentary leishmaniasis and AIDS is poorly characterized. Objectives To describe a series of patients coinfected with Leishmania and human immunodeficiency virus (HIV). Methods Clinical records from patients were analysed by demographic data, clinical manifestations, diagnoses, treatments and outcomes. Results Fifteen cases of AIDS/tegumentary leishmaniasis were found. The diagnosis of leishmaniasis was confirmed by the detection of Leishmania amastigotes or antigens from the cutaneous or mucosal lesions. The mean CD4+ T-cell count was 84 cells mm−3 (range 8–258) and all patients were classified as having AIDS according to the Centers for Disease Control and Prevention. A wide range of manifestations was found, varying from a single ulcer to multiple and polymorphic lesions. Mucosal lesions were present in 80% and cutaneous lesions in 73% of patients (53% with mucocutaneous form), disseminated lesions in 60% and genital lesions in 27% of patients. All patients received anti- Leishmania therapy and 53% showed relapses. Sixty-seven per cent received highly active antiretroviral therapy but showed no difference in outcomes and relapses compared with those not using medication. Forty per cent died during the study period. In these patients, the anti- Leishmania antibody and Montenegro skin test were useful in the diagnosis of leishmaniasis, probably because leishmaniasis preceded immunosuppression due to HIV infection. Conclusions Clinical manifestations of tegumentary leishmaniasis in HIV-infected patients are diverse. Our data emphasize possible unusual manifestations of this disease in HIV-infected patients, particularly in severely immunosuppressed cases (< 200 CD4+ cells mm−3). [ABSTRACT FROM AUTHOR]

Background Mast cells (MCs) are related with healing process in chronic inflammatory diseases, although in cutaneous leishmaniasis (CL) its importance is unknown. The aim of this study was to determine the correlation of MC with clinical findings in patients with the localized form of CL. Methods A cohort of 85 patients with CL was evaluated. MCs count was performed in pre-treatment biopsies and correlation with clinical findings and Leishmania species determined by PCR were performed. Results The MCs count in patients with CL caused by Leishmania (V.) braziliensis was 14·3 ± 9·8 cells/mm2, and 7·0 ±  6·5 cells/mm2 in patients with L. (L.) amazonensis (P  < 0·05). The linear regression of MCs count with the age showed a tendency of cell number decreasing, according to ageing of the patient (r 2 = 0·05; P  < 0·05). The association of disease's duration and MCs count was positive (r 2 = 0·11; P  < 0·05). There was not any association of MCs count with number of lesions neither with Leishmania antigen expression. The MCs count was higher in patients with earlier healing after treatment (P  < 0·05). Conclusion MC can be important in CL and related with healing lesion. [ABSTRACT FROM AUTHOR]

Suitable levels of interferon (IFN)-γ and interleukin (IL)-10 seem to favour the outcome of cutaneous leishmaniasis (CL), while high IFN-γ and low IL-10 production are associated with severity of mucosal leishmaniasis (ML). Considering that cytokine balance is important for the maintenance of protective responses in leishmaniasis, our aim was to investigate leishmanial antigens-induced IFN-γ and IL-10 levels maintained in healed individuals who had different clinical outcomes of Leishmania infection. Thirty-three individuals who recovered from L. braziliensis infection were studied: cured CL (CCL), cured ML (CML), spontaneous healing of CL (SH) or asymptomatic individuals (ASY). Cytokines were quantified by enzyme-linked immunosorbent assay (ELISA) in culture supernatants of L. braziliensis-stimulated peripheral blood mononuclear cells (PBMC). IFN-γ levels were higher in CML (7593 ± 5994 pg/ml) in comparison to SH (3163 ± 1526 pg/ml), ASY (1313 ± 1048 pg/ml) or CCL (1897 ± 2087 pg/ml). Moreover, cured ML cases maintained significantly lower production of IL-10 (127 ± 57·8 pg/ml) in comparison to SH (1373 ± 244 pg/ml), ASY (734 ± 233 pg/ml) or CCL (542 ± 375 pg/ml). Thus, a high IFN-γ/IL-10 ratio observed in CML can indicate unfavourable cytokine balance. On the other hand, no significant difference in the IFN-γ/IL-10 ratio was observed when CCL individuals were compared to SH or ASY subjects. In conclusion, even after clinical healing, ML patients maintained a high IFN-γ/IL-10 secretion profile in response to leishmanial antigens. This finding can explain a delayed down-modulation of exacerbated inflammatory responses, which can be related in turn to the necessity of prolonged therapy in ML management. Conversely, lower IFN-γ/IL-10 balance observed in CCL, SH and ASY individuals can represent a better-modulated immune response associated with a favourable prognosis. [ABSTRACT FROM AUTHOR]