Abstract / Summary
Background: Visceral leishmaniasis (VL), or kala-azar, is one of the most devastating neglected tropical diseases, disproportionately affecting children in resource-limited endemic regions across four major geographic zones. Despite decades of research, no comprehensive systematic review has rigorously compared clinical and hematological manifestations of pediatric VL across these regions, leaving clinicians without evidence-based, region-specific guidelines.
Objectives: To analyze and compare the clinical, hematological, and epidemiological patterns of pediatric VL across four major endemic regions: Mediterranean/Europe, Latin America, East/Central Africa, and Asia (West, Central, and East). Secondary objectives included comparing parasite species distributions, diagnostic approaches, treatment regimens, complication profiles, and case-fatality rates.
Methods: A systematic literature search following PRISMA 2020 guidelines and PRISMA-S reporting standards was conducted across Pub-Med/MEDLINE, Scopus, ISI Web of Science, EMBASE, and CINAHL. The review protocol was retrospectively registered with the International Prospective Register of Systematic Reviews (PROSPERO; Registration No.: CRD420261446750). Retrospective PROSPERO registration is acknowledged as a limitation of this review. Duplicate records were removed using Rayyan software. From 1,482 identified records, after removing 117 duplicates and applying pre-specified inclusion/exclusion criteria, 40 studies met all eligibility criteria: Mediterranean/Europe (n=13), Latin America (n=6), East/Central Africa (n=6), and Asia (n=15). Study quality was assessed using the Newcastle-Ottawa Scale and the Joanna Briggs Institute Critical Appraisal Checklist. Cross-tabulations were performed for exploratory descriptive purposes; results are presented as narative synthesis.
Results: Apparent geographic variations were observed. Fever was near-universal (91-100%) across all regions. Splenomegaly ranged from 90% to 98%, and hepatomegaly from 65% to 89%. Anemia prevalence ranged from 78% to 95%, pancytopenia from 45% to 72%, and thrombocytopenia from 62% to 92% (based on exploratory cross-tabulations). Leishmania infantum predominated in Mediterranean/European and Latin American regions; L. donovani prevailed in African and Asian cohorts. Treatment regimens, diagnostic methods, and complication profiles showed substantial regional differences.
Conclusions: Apparent geographic variations exist in pediatric VL manifestations, which may be associated with differences in parasite species, host genetics, nutritional status, healthcare infrastructure, and co-infection patterns. Region-specific diagnostic and therapeutic guidelines are urgently needed and should be supported by enhanced surveillance and collaborative international research.