Evaluation of medullary cytokine expression and clinical and laboratory aspects in severe human visceral leishmaniasis.

BACKGROUND: Visceral leishmaniasis (VL) is a serious public health problem. The factors that can determine whether VL develops and progresses to severe form have not been fully identified, but a specific cellular immune response appears to play a key role. Therefore, understanding immunopathogenesis can be useful in preventing a serious clinical outcome. MATERIALS AND METHODS: Bone marrow samples were collected from patients with severe VL (SVL) or non-severe VL (NSVL). Cytokine levels and parasitic load were analysed by RT-qPCR. There is a statistically significant difference in the leukocyte parameter in patients with SVL and NSVL compared with the control patients (p = .006 and p = .014, respectively). RESULTS: Urea, alanine transaminase and albumin parameters had a significant difference p = .036, p = .039 and p = .017, respectively, between SVL and NSVL. Although high levels of IFN-γ, IL-10, IL-6 and TNF-α were present in all groups of individuals with VL, they were not statistically associated with severity. In patients with active VL, IFN-γ and IL-10 were associated, respectively, with a reduction and increase in the parasite load, strong and significant positive association between IFN-γ and IL-10 (rho = .627 and p = .003). CONCLUSION: This study demonstrates that VL stimulates an non-dichotomized inflammatory response between Th1/Th2 and that bone marrow is an important tissue for immune regulation.

Hemophagocytic lymphohistiocytosis secondary to visceral leishmaniasis in an endemic area in the north of Minas Gerais, Brazil.

INTRODUCTION: Visceral leishmaniasis (VL) is an ill-studied disease that is endemic to several regions of Brazil. It is often complicated by hemophagocytic lymphohistiocytosis (HLH), a potentially fatal disorder resulting from excessive non-malignant activation/proliferation of T lymphocytes and macrophages. Considering the overlapping clinical and laboratory characteristics of these diseases, diagnosing HLH is a challenge. Therefore, tracking the association between VL and HLH is necessary in endemic areas. Although HLH can be inapparent and resolve with antileishmanicides, this may not always occur. HLH causes high lethality; therefore, immunosuppressive therapy should be instituted immediately in order to avoid a fatal outcome. METHODS: We described the epidemiological, clinical, laboratory, and therapeutic profile of this association in a region of Brazil endemic for VL. RESULTS: We presented 39 patients with this association in a retrospective cohort of 258 children who were admitted from January 2012 to June 2017. Of the 39 patients, 31 were from urban areas (79.5%), and 21 (53%) were males. The mean age and weight were 2.86 (2.08) years and 14.03 (5.96) kg, respectively. The main symptoms were fever (100%), hepatosplenomegaly (100%), pallor of the skin and mucosa (82.5%), edema (38.5%), bleeding (25%), and jaundice (7.5%). Hemophagocytosis was identified in 16/37 (43.24%) patients, and direct examination revealed that 26/37 (70.27%) patients were positive for VL. The patients were treated as recommended by the Ministry of Health. CONCLUSIONS: It was observed that HLH is a common complication in endemic areas, and its diagnosis must consider the overlapping of clinical characteristics and pancytopenia.

Laboratorial algorithm for serological diagnosis of visceral leishmaniasis using rK39-ICT, DAT-LPC and FC-Simplex IgG1.

The performance of distinct serological tests (rK39-ICT, IFAT, DAT-LPC, FC-Simplex IgG1) was assessed and a laboratorial algorithm was proposed for accurate diagnosis of VL. DAT-LPC and FC-Simplex IgG1 showed outstanding accuracy (AUC = 0.93) to identify VL patients. The use of a sequential serological algorithm (rK39-ICT screening followed by DAT-LPC or FC-Simplex IgG1) improved the global accuracy for VL (97.2%) diagnosis. An alternative approach for diagnosis of VL has been also assessed for interchangeable use of serum/whole blood lysate samples in DAT-LPC and FC-Simplex IgG1. Our data showed an outstanding agreement for the results obtained with whole blood lysate samples as compared to serum samples (DAT-LPC =100%; FC-Simplex IgG1 = 99%). Together, these findings provide insights to improve the current overall accuracy of VL diagnosis and present innovative laboratorial tests and alternative samples from use in public health services.

Hemophagocytic lymphohistiocytosis secondary to visceral leishmaniasis in an endemic area in the north of Minas Gerais, Brazil

Abstract INTRODUCTION Visceral leishmaniasis (VL) is an ill-studied disease that is endemic to several regions of Brazil. It is often complicated by hemophagocytic lymphohistiocytosis (HLH), a potentially fatal disorder resulting from excessive non-malignant activation/proliferation of T lymphocytes and macrophages. Considering the overlapping clinical and laboratory characteristics of these diseases, diagnosing HLH is a challenge. Therefore, tracking the association between VL and HLH is necessary in endemic areas. Although HLH can be inapparent and resolve with antileishmanicides, this may not always occur. HLH causes high lethality; therefore, immunosuppressive therapy should be instituted immediately in order to avoid a fatal outcome. METHODS: We described the epidemiological, clinical, laboratory, and therapeutic profile of this association in a region of Brazil endemic for VL. RESULTS We presented 39 patients with this association in a retrospective cohort of 258 children who were admitted from January 2012 to June 2017. Of the 39 patients, 31 were from urban areas (79.5%), and 21 (53%) were males. The mean age and weight were 2.86 (2.08) years and 14.03 (5.96) kg, respectively. The main symptoms were fever (100%), hepatosplenomegaly (100%), pallor of the skin and mucosa (82.5%), edema (38.5%), bleeding (25%), and jaundice (7.5%). Hemophagocytosis was identified in 16/37 (43.24%) patients, and direct examination revealed that 26/37 (70.27%) patients were positive for VL. The patients were treated as recommended by the Ministry of Health. CONCLUSIONS It was observed that HLH is a common complication in endemic areas, and its diagnosis must consider the overlapping of clinical characteristics and pancytopenia.

Evaluation of cross reactivity between Trypanosoma cruzi and Leishmania infantum in serologically ineligible blood donors due to chagas diseas

Inconclusive serological screening for Trypanosoma cruzi has been a problem for blood banks. This study examined the performance of serological techniques for Chagas disease in reagent samples from blood bank screenings and verified the possibilities of cross reactivity with visceral leishmaniasis. 68 samples of reagent donors tested with ELISA for Chagas disease were evaluated by other techniques and for the detection of anti-Leishmania antibodies. Four donors (5.9%) with positive results for T. cruzi were positive for ELISA Kalazar Detect (visceral leishmaniasis),three of which were confirmed by Western blot. This study confirms the specificity of the tests for Chagas disease in blood banks and reinforces the urgent adoption of measures to assess the real risk of transfusion transmission of visceral leishmaniasis

Metformin Reduces Lipogenesis Markers in Obese Mice Fed a Low-Carbohydrate and High-Fat Diet.

Lipogenesis is the process by which fatty acids are synthesized. In metabolic syndrome, an insulin resistant state along with high plasma levels of free fatty acids (FFA) and hyperglycemia may contribute to the lipogenic process. The aim of the present study was to investigate the effects of oral administration of metformin on the expression of lipogenic genes and glycemic profile in mice fed with low-carbohydrate high-fat diet by evaluating their metabolic profile. SWISS male mice were divided into 4 groups (N = 7) that were fed with standard (ST), standard plus metformin (ST + MET), low-carbohydrate high-fat diet (LCHFD) and low-carbohydrate high-fat diet plus metformin (LCHFD + MET) (100 mg kg-1 diet) diets respectively. Food intake, body weight and blood parameters, such as glucose tolerance, insulin sensitivity, glucose, HDL-c, total cholesterol, triglycerides, ASL and ALT levels were assessed. Histological analyses were performed on hematoxylin and eosin-stained epididymal adipose tissue histological specimens. The expression levels of peroxisome proliferator-activated receptor (PPARγ), sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC), were assessed by RT-PCR. This study showed that metformin decreased adipocyte area, body weight and food consumption in obese animals when compared to the standard group. Furthermore, the expression of lipogenic markers in adipose tissue were diminished in obese animals treated with metformin. This data showed that oral administration of metformin improved glucose and lipid metabolic parameters in white adipose tissue by reducing the expression of lipogenesis markers, suggesting an important clinical application of MET in treating obesity-related diseases in metabolic syndrome.

Distinct metabolic effects of resveratrol on lipogenesis markers in mice adipose tissue treated with high-polyunsaturated fat and high-protein diets.

OBJECTIVE: A healthy diet is essential for the prevention of metabolic syndrome. The present study evaluated the effect of resveratrol associated with high-polyunsaturated fat and high-protein diets on expression of adipogenic and lipogenic genes. RESEARCH METHODS & PROCEDURES: FVB/N mice were divided into 6 groups (n=7 each) and fed with experimental diets for 60days: standard (ST), high-fat diet (HFD), and high-protein diet (HPD), with and without resveratrol (RSV) (4g/kg diet). The body weight, food intake, energy intake (kcal), and blood parameters (HDL-C, total cholesterol, glucose, and triglyceride levels) were assessed. Real-time PCR was performed to analyze the expression of adipogenesis and lipogenesis markers: PPARγ, SREBP-1c, ACC and FAS in samples from perigonadal adipose tissue. RESULTS: In the HPD+RSV group, resveratrol decreased body weight, body adiposity, adipose tissue weight, adipocyte area, total cholesterol, ACC and FAS expression, and increased HDL-cholesterol in comparison to HPD. In the HPD group there was a decrease in adipocyte area, as well as PPARγ, SREBP-1c and ACC expression in comparison to ST. While in HFD+RSV, resveratrol decreased levels of total cholesterol in comparison to HFD. In the HFD group there was decrease in body weight, and PPARγ, SREBP-1c and ACC expression in comparison to ST. CONCLUSIONS: The obtained results show that resveratrol decreases lipogenesis markers and metabolic parameters in the setting of a high-protein diet. Moreover, resveratrol decreased total cholesterol in both diets. These results point to the increased potential of resveratrol use in prevention of metabolic syndrome, acting on different dietary compositions.

Plasma concentrations of tumour necrosis factor-alpha, tumour necrosis factor-related apoptosis-inducing ligand, and FasLigand/CD95L in patients with Chagas cardiomyopathy correlate with left ventricular dysfunction.

AIMS: Cardiomyocyte apoptosis is reported to be involved in the pathogenesis of human chronic Chagas cardiomyopathy (CCC). Members of the tumour necrosis factor (TNF) superfamily (TNF-alpha, FasLigand/CD95L, and TNF-related apoptosis-inducing ligand) are known to activate the death receptor pathway. We therefore investigated whether levels of TNF-alpha, FasLigand/CD95L, and TRAIL correlated with changes in heart function of patients with Chagas disease (n = 31). METHODS AND RESULTS: Concentrations of TNF-alpha and TRAIL were clearly augmented in individuals with severe form CCC (n = 16). Levels of FasLigand/CD95L were greater in chagasic patients than in non-infected individuals (n = 15) but did not differentiate between clinical forms of Chagas disease. There was a good correlation between TNF-alpha (r = 0.85 and r = 0.68, P < 0.0001) or TRAIL (r = 0.68 and r = 0.60, P < 0.001) and left ventricular ejection fraction (LVEF) and left ventricular diastolic diameter (LVDD), respectively. In addition, TNF-alpha (r = 0.57, P = 0.0001), TRAIL (r = 0.56, P = 0.001), and FasLigand/CD95L (r = 0.51, P = 0.001) showed a good correlation with brain natriuretic peptide, a well-known parameter of ventricular dysfunction in CCC. There was a weak correlation between levels of FasLigand/CD95L (r = 0.50, P < 0.004) and both LVEF and LVDD. There was no correlation between levels of TNF superfamily ligands and chronotropic incompetence, maximal heart rate, or number of ventricular premature beats in 24 h. CONCLUSION: Plasma levels of TNF superfamily ligands are elevated in patients with functional but not arrhythmogenic disturbances, and these death receptor ligands may be potential markers of ventricular dysfunction in CCC.