Diagnosis and Management of Visceral Leishmaniasis in Children: A French Retrospective Study.

Background: Few studies have investigated the diagnosis and management of pediatric visceral leishmaniasis (VL) in high-income countries. Methods: All children hospitalized for VL in university hospitals across mainland France between January 2012 and August 2022 were included in this retrospective study. Results: Sixty-three patients were included with an M/F sex ratio of 1.25 and a median age of 2 years (IQR: 1; 5.4). At least 36 patients had autochthonous VL. The median delay between symptom onset and diagnosis was 20 days (IQR: 11.7; 35.2) [1-193]. The most common symptoms were fever (92%) and splenomegaly (78%). Biological findings included inflammatory syndrome (90%), pancytopenia (79%), and hepatic cytolysis (52%). Twenty-four children (44%) presented hemophagocytic lymphohistiocytosis (HLH). Bone marrow smears, bone marrow real-time PCR (qPCR), and blood qPCR were positive for VL in 64%, 90%, and 96% of the tested patients, respectively. Positivity reached 100% in patients who underwent combined blood and bone marrow PCR. All the patients were treated with liposomal amphotericin B (chemical name, (1R,3S,5R,6R,9R,11R,15S,16R,17R,18S,19E,21E,23E,25E,27E,29E,31E,33R,35S,36R,37S)-33-[(2R,3S,4S,5S,6R)-4-amino-3,5-dihydroxy-6-methyloxan-2-yl]oxy-1,3,5,6,9,11,17,37-octahydroxy-15,16,18-trimethyl-13-oxo-14,39-dioxabicyclo[33.3.1]nonatriaconta-19,21,23,25,27,29,31-heptaene-36-carboxylic acid;2-aminoguanidine). Ten different regimens were used, ranging from 18 to 30 mg/kg cumulative doses given from 2 to 8 days. The median follow-up duration was 2.8 months. Four patients (6.3%) relapsed, one of whom was not retreated. All the children recovered. Conclusions: Pediatric VL remains rare in France, with long diagnostic delays and a high frequency of HLH. The combination of blood and bone marrow PCR optimizes the diagnosis. Standardization of therapeutic regimens and follow-up is necessary.