Visceral leishmaniasis: a common cause of post-infectious febrile pancytopenia in children in an endemic area: experience of a children's tertiary hospital

The estimated distribution of autochthonous leishmaniasis by Leishmania infantum in Europe in 2005-2020

BACKGROUND

This study describes the spatial and temporal distribution between 2005 and 2020 of human and animal leishmaniasis by Leishmania infantum in European countries reporting autochthonous cases, and highlights potential activities to improve disease control.

METHODOLOGY/PRINCIPAL FINDINGS

It was based on a review of the scientific literature and data reported by the World Health Organization (WHO), the World Organization for Animal Health (WOAH) and the Ministries of Health, including hospital discharges in some countries. Autochthonous infections were reported in the scientific literature from 22 countries, including 13 and 21 countries reporting human and animal infections, respectively. In contrast, only 17 countries reported autochthonous human leishmaniasis cases to the WHO and 8 countries animal infections to the WOAH. The number of WOAH reported cases were 4,203, comprising 4,183 canine cases and 20 cases in wildlife. Of 8,367 WHO reported human cases, 69% were visceral leishmaniasis cases-of which 94% were autochthonous-and 31% cutaneous leishmaniasis cases-of which 53% were imported and mostly in France. The resulting cumulative incidence per 100,000 population of visceral leishmaniasis between 2005-2020, was highest in Albania (2.15 cases), followed by Montenegro, Malta, Greece, Spain and North Macedonia (0.53-0.42), Italy (0.16), Portugal (0.09) and lower in other endemic countries (0.07-0.002). However, according to hospital discharges, the estimated human leishmaniasis incidence was 0.70 in Italy and visceral leishmaniasis incidences were 0.67 in Spain and 0.41 in Portugal.

CONCLUSIONS/SIGNIFICANCE

Overall, there was no evidence of widespread increased incidence of autochthonous human leishmaniasis by L. infantum in European countries. Visceral leishmaniasis incidence followed a decreasing trend in Albania, Italy and Portugal, and peaked in Greece in 2013, 2014 and 2017, and in Spain in 2006-2007 and 2011-2013. Animal and human cutaneous leishmaniasis remain highly underreported. In humans, hospital discharge databases provide the most accurate information on visceral leishmaniasis and may be a valuable indirect source of information to identify hotspots of animal leishmaniasis. Integrated leishmaniasis surveillance and reporting following the One Health approach, needs to be enhanced in order to improve disease control.

CD4+ T Cells Alter the Stromal Microenvironment and Repress Medullary Erythropoiesis in Murine Visceral Leishmaniasis

Human visceral leishmaniasis, a parasitic disease of major public health importance in developing countries, is characterized by variable degrees of severity of anemia, but the mechanisms underlying this change in peripheral blood have not been thoroughly explored. Here, we used an experimental model of visceral leishmaniasis in C57BL/6 mice to explore the basis of anemia following infection with Leishmania donovani. 28 days post-infection, mice showed bone marrow dyserythropoiesis by myelogram, with a reduction of TER119+ CD71-/+ erythroblasts. Reduction of medullary erythropoiesis coincided with loss of CD169high bone marrow stromal macrophages and a reduction of CXCL12-expressing stromal cells. Although the spleen is a site of extramedullary erythropoiesis and erythrophagocytosis, splenectomy did not impact the extent of anemia or affect the repression of medullary hematopoiesis that was observed in infected mice. In contrast, these changes in bone marrow erythropoiesis were not evident in B6.Rag2-/- mice, but could be fully reconstituted by adoptive transfer of IFNγ-producing but not IFNγ-deficient CD4+ T cells, mimicking the expansion of IFNγ-producing CD4+ T cells that occurs during infection in wild type mice. Collectively, these data indicate that anemia during experimental murine visceral leishmaniasis can be driven by defects associated with the bone marrow erythropoietic niche, and that this represents a further example of CD4+ T cell-mediated immunopathology affecting hematopoietic competence.

Childhood Visceral Leishmaniasis: Distinctive Features and Diagnosis of a Re-emerging Disease. An 11-year Experience From a Tertiary Referral Center in Athens, Greece

BACKGROUND

Visceral leishmaniasis (VL) remains a public health issue in Greece. The aim of this study was to describe the clinical and epidemiologic characteristics of pediatric VL in our region as well as to evaluate the laboratory findings and the diagnostic techniques that are applied.

METHODS

We retrospectively reviewed the medical records of all children diagnosed with VL in an 11-year period at a tertiary public hospital in the region of Athens. Demographic features, clinical information and laboratory findings were accessed.

RESULTS

A total of 43 cases were recorded during 2005-2015. Median age of the patients was 3.7 years. Pallor (100%), fever (98%), hepatosplenomegaly (55.8%) and appetite loss (32.6%) were the most common presentations of the disease. The predominant laboratory abnormalities were anemia (100%), thrombocytopenia (90.7%), elevated inflammatory markers (86.1%) and decreased albumin/globulin (A/G) ratio (72.1%). Four patients developed secondary hemophagocytic lymphohistiocytosis syndrome, whereas in 3 others abdominal ultrasound showed splenic nodules. Bone marrow aspiration detected Leishmania parasites in 92.7% of cases and the rapid rK39 strip test indicated anti-Leishmania antibodies in 97.1% of children. In addition, all patients in whom indirect immunofluorescent antibody test was implemented had positive results.

CONCLUSIONS

VL still affects children in our area. Fever, splenomegaly, anemia and appetite loss are the typical findings in children. Noninvasive techniques (immunofluorescent antibody test, rK39) in combination with bone marrow microscopy are useful in the diagnosis of pediatric VL.

Pediatric visceral leishmaniasis in northwest of Iran

Leishmaniasis is one of the major health problems in Iran. Although the incidence of visceral leishmaniasis (VL) is reported almost everywhere, the northwestern Iran is one of the major endemic regions.To do this study, clinical, laboratory as well as disease characteristics of children admitted to Children Cure and Health Hospital, Tabriz University of Medical Sciences, were examined as the reference hospital for the treatment of VL in northwestern Iran.In this study, 156 children hospitalized in a pediatric hospital from 2000 to 2015 for VL were included. Gender, age, anemia, thrombocytopenia, increase in the erythrocyte sedimentation rate (ESR), alanine transaminase (SGPT), and aspartate transaminase (SGOT), major clinical manifestations such as fever, splenomegaly, hepatomegaly, treatment type, and the disease were studied.Among 156 patients examined in this study, 88 (56.41%) and 68 (43.59%) participants were male and female, respectively. The minimum and maximum ages of the infection were 4.5 months and 6 years, respectively. The mean age of the infected children was 17.94 months. Fever (94.24%) and splenomegaly (86.53%) were the most common symptoms of this disease among children. In addition, 49 (31.41%), 64 (41.02%), 18 (11.53%), 33 (21.15%), and 40 (25.64%) participants had leukopenia, hemoglobin count below 8, ESR above 100, ESR above 60, and platelets below 100,000, respectively. Moreover, 39 (25%) and 17 (10.89%) patients had high aspartate transaminase (AST) and alanine transaminase (ALT). Also, 96.2% of the participants responded to the treatment with glucantime. The rate of mortality in this study was 3.2%.Clinically, almost all children had fever and splenomegaly at the onset of the disease. In addition, hepatic involvement was observed in all cases of mortality, cases with a lack of initial response, and those in need of auxiliary medication. Hepatic involvement appears to be related to the prognosis of the disease. In our study, bone marrow aspiration (BMA) and positive direct antiglobulin test (DAT) were observed in 66.67% and more than 90% of the patients, respectively.Children with VL in northwestern Iran responded well to glucantime. In case of resistance, amphotericin B was a good alternative. Early diagnosis is essential in reducing mortality rate.

Transient neutropenia in children with febrile illness and associated infectious agents: 2 years' follow-up

The aim of the study was to identify the relationship of acquired neutropenia with childhood infections and to assess its clinical course, complications, and outcome. Children admitted to two pediatric wards over a 4-year period with febrile neutropenia were prospectively investigated for underlying infections with inflammatory markers, cultures of body fluids, and serological tests. The study included 161 previously healthy children with febrile neutropenia/leukopenia aged (mean ± SD) 3.02 ± 3.86 years (range, 0.1-14). One hundred and thirty-six out of 161 patients (84.5 %) had transient neutropenia (TN), while in 25 patients, neutropenia was chronic (CN) and persisted for ≥180 days. An infectious agent was isolated in 98/161 (60.9 %) cases, in 68.4 % patients with TN, and in 20 % of those with CN (p = 0.001). Among the patients with CN, seven had positive antineutrophil antibodies (autoimmune neutropenia) and four were eventually diagnosed with hematological malignancy. In all age groups, TN was of short duration (<1 month), of mild to moderate severity, and was predominantly associated with viral infections. Two years after diagnosis, 143/161 children (88.8 %) were available for follow-up. One hundred and thirty-seven of 143 (95.8 %) had recovered completely, while the rest remained neutropenic. The latter patients had a benign course despite severe neutropenia. In conclusion, febrile neutropenia during childhood is usually transient, often following viral and common bacterial infections, without serious complications and in the majority of cases it resolves spontaneously. However, in a considerable percentage of patients, neutropenia is discovered incidentally during the course of an infection on the ground of an underlying hematological disease.