Immunologic Markers of Clinical Evolution in Children Recently Infected with Leishmania donovani chagasi

Abstract

The study attempted to identify immunologic markers for progression of Leishmania donovani chagasi infection to disease in children in an area endemic for visceral leishmaniasis (VL). [3H]thymidine uptake of lymphocytes stimulated with L. donovani chagasi antigen from children with asymptomatic infection (25,286 +/- 11,648) and from children with self-healing subclinical infection (15,511 +/- 4681) was greater (P = .001) than that observed with lymphocytes from children who progressed to classic VL (4811 +/- 2984). The interferon-gamma (IFN-gamma) levels from asymptomatic and subclinically infected children (74 +/- 90 units/ml) were higher (P = .02) than those observed in children who progressed to VL (7 +/- 8 units/ml). Absence of lymphocyte blastogenesis and IFN-gamma production were associated with progression of infection to classic VL. In the presence of these markers, children should be closely followed to identify signs and symptoms that would permit early initiation of therapy.

Immunity to a salivary protein of a sand fly vector protects against the fatal outcome of visceral leishmaniasis in a hamster model

“…4B), supporting the observation that the liver and spleen show organ specific immunity reaching a fine balance between parasite clearance and parasite pathology (32). IFN-␥ plays an important role in limiting the growth of Leishmania in murine and human macrophages and limiting leishmaniasis progression (21,33). Moreover, NO generation through IFN-␥ is the critical macrophage effector mechanism in the control of parasite replication in mice (34).…”

Hyponatremia in visceral leishmaniasis

“…The visceral form of the disease, fatal if not treated, is caused in Brazil by Leishmania donovani chagasi, species associated with endemic outbreaks. Kala-azar causes an intense immune dysfunction with polyclonal activation of B lymphocytes and depression in cellular and humoral immunities 10 . Visceral leishmaniasis progresses with intense inflammatory alterations in vital organs such as the lungs, liver, spleen, kidneys, digestive tract and bone marrow.…”

Reference Values for Leishmania Infantum Parasitemia in Different Clinical Presentations: Quantitative Polymerase Chain Reaction for Therapeutic Monitoring and Patient Follow-Up

“…The ability of in vitro assays to detect such silent infections differs among the different disease-endemic areas for VL and the technical means used. 3,4 Increased sensitivity for Leishmania detection has been achieved by means of the polymerase chain reaction (PCR), notably by targeting kinetoplast DNA. Analysis of the results obtained with different assays indicates that in the Mediterranean area the parasitic load in asymptomatic carriers is lower than that observed when the disease is diagnosed.…”