Search results for "visceral leishmaniasis"

Good's syndrome and recurrent leishmaniasis: A case report and review of literature

2020

We report the case of a 56-year-old Caucasian male affected by thymoma and myasthenia gravis that developed recurrent visceral leishmaniasis 11 years after thymectomy. After treatment of each relapse with liposomal amphotericin B the PCR-Leishmania was negative and the patient showed clinical improvement. An immunologic work-up was performed showing lymphopenia with an important decrease in CD4+ T cells (52 cells/μ) and CD4/CD8 ratio (0.2). HIV test was negative. On the basis of previous thymoma and myasthenia gravis and on the basis of the immunological profile a diagnosis of Good's syndrome was made. Since IFNγ plays a main role in the control of Leishmania infection the production of IFN…

Disease severity in patients with visceral leishmaniasis is not altered by co-infection with intestinal parasites

2017

Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was s…

Direct-acting antivirals and visceral leishmaniasis: a case report

2019

Abstract Background Visceral leishmaniasis is a vector-borne parasitic disease caused by protozoa belonging to the genus Leishmania. The clinical presentation of visceral leishmaniasis strictly depends on the host immunocompetency, whereas depressive conditions of the immune system impair the capability to resolve the infection and allow reactivation from sites of latency of the parasite. Case presentation We describe a case of visceral leishmaniasis (VL) that occurred in a patient with chronic hepatitis C treated with direct-acting antiviral drugs (DAA). The hypothesized mechanism is the alteration of protective inflammation mechanisms secondary to DAA therapy. Downregulation of type II an…

The Absence of HIF-1α Increases Susceptibility to Leishmania donovani Infection via Activation of BNIP3/mTOR/SREBP-1c Axis

2020

Summary: Hypoxia-inducible factor-1 alpha (HIF-1α) is considered a global regulator of cellular metabolism and innate immune cell functions. Intracellular pathogens such as Leishmania have been reported to manipulate host cell metabolism. Herein, we demonstrate that myeloid cells from myeloid-restricted HIF-1α-deficient mice and individuals with loss-of-function HIF1A gene polymorphisms are more susceptible to L. donovani infection through increased lipogenesis. Absence of HIF-1α leads to a defect in BNIP3 expression, resulting in the activation of mTOR and nuclear translocation of SREBP-1c. We observed the induction of lipogenic gene transcripts, such as FASN, and lipid accumulation in inf…

2016

Immunologically, active visceral leishmaniasis (VL) is characterised by profound immunosuppression, severe systemic inflammatory responses and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis, however, their role in human visceral leishmaniasis is poorly understood. In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-l…

2016

One of the key immunological characteristics of active visceral leishmaniasis (VL) is a profound immunosuppression and impaired production of Interferon-γ (IFN-γ). However, recent studies from Bihar in India showed using a whole blood assay, that whole blood cells have maintained the capacity to produce IFN-γ. Here we tested the hypothesis that a population of low-density granulocytes (LDG) might contribute to T cell responses hyporesponsiveness via the release of arginase. Our results show that this population is affected by the anticoagulant used to collect blood: the frequency of LDGs is significantly lower when the blood is collected with heparin as compared to EDTA; however, the antico…

Evaluation of serum levels of soluble CD4, CD8 and β2-microglobulin in visceral human leishmaniasis

1994

SUMMARY The levels of soluble CD4 (sCD4), sCD8 and β2-microglobulin (β2-M) were measured in sera from patients with visceral leishmaniasis during the course of infection. Levels of sCD4. sCD8 and β2-M were raised significantly above levels In normal sera and returned to the normal range after recovery. The decrease in the levels of CDS was related to a reduction of anaemia, leukopenia and thrombocytopenia. In contrast, sCD4 levels fluctuated during the period of infection. β2-M returned within normal range more rapidly than sCD8 secretion. Our results suggest that T cells are activated during infection, and that it is also possible that the raised levels of these soluble molecules play a ro…

Asymptomatic Leishmania infantum/chagasi infection in blood donors of western Sicily.

2007

The purpose of this study was to evaluate whether the risk of transfusion-transmitted visceral leishmaniasis was present in an area of western Sicily where the incidence of the disease is higher than the regional average. From May to December 2005, 1449 blood donors from Agrigento district (Sicily, Italy) were screened for the presence of anti-Leishmania antibodies by an indirect immunofluorescent antibody test (IFAT). Blood samples from IFAT-positive donors were examined by PCR to detect Leishmania DNA. Anti-Leishmania antibodies were found in 11 (0.75%) cases, among which Leishmania DNA was detected from four (36.4%). Particular techniques to inactivate different pathogens would be consid…

Role of PCR in Diagnosis and Prognosis of Visceral Leishmaniasis in Patients Coinfected with Human Immunodeficiency Virus Type 1

2001

ABSTRACT A group of 76 consecutive human immunodeficiency virus (HIV)-positive patients with fever of unknown origin ( n = 52) or fever associated with pulmonary diseases was evaluated in order to assess the usefulness of PCR with peripheral blood in the diagnosis and follow-up of visceral leishmaniasis. We identified 10 cases of visceral leishmaniasis among the 52 patients with fever of unknown origin. At the time of diagnosis, all were parasitemic by PCR with peripheral blood. During follow-up, a progressive decline in parasitemia was observed under therapy, and all patients became PCR negative after a median of 5 weeks (range, 6 to 21 weeks). However, in eight of nine patients monitored …

Cryptic Leishmania infantum infection in Italian HIV infected patients.

2008

Abstract Background Visceral leishmaniasis (VL) is a protozoan diseases caused in Europe by Leishmania (L.) infantum. Asymptomatic Leishmania infection is more frequent than clinically apparent disease. Among HIV infected patients the risk of clinical VL is increased due to immunosuppression, which can reactivate a latent infection. The aims of our study were to assess the prevalence of asymptomatic L. infantum infection in HIV infected patients and to study a possible correlation between Leishmania parasitemia and HIV infection markers. Methods One hundred and forty-five HIV infected patients were screened for the presence of anti-Leishmania antibodies and L. infantum DNA in peripheral blo…