Clinical spectrum of pediatric histoplasmosis in Mexico: description of seven cases and literature review

Abstract

Histoplasmosis is a systemic mycosis caused by the dimorphic fungus Histoplasma capsulatum (H.capsulatum) . It represents a diagnostic challenge in the pediatric population due to its non-specific clinical presentation, frequently mimicking tuberculosis or malignancies. This study aims to describe the clinical, radiological, and laboratory characteristics of a case series of pediatric patients to optimize early recognition and timely management. a retrospective and descriptive review of all proven histoplasmosis cases (EORTC/MSGERC criteria) diagnosed and managed at Instituto Nacional de Pediatría, a tertiary-care national referral pediatric center in Mexico over a 5-year period (2020–2025). Demographic, clinical, mycological, and therapeutic variables were analyzed. The median age was 12 years (range: 1–15 years), with male predominance (71.4%). Underlying immunosuppression or comorbidities (HIV/AIDS, hematological malignancies and renal transplantation) were present in 57.1% of cases. Relevant epidemiological exposure was identified in 71.4% of patients. Persistent fever was the most frequent symptom (85.7%). Extrapulmonary involvement was documented in three patients (42.8%), including mesenteric lymph node, bone marrow, and epidural involvement. One patient developed hemophagocytic lymphohistiocytosis. Diagnosis was established by histopathology (85.7%). Liposomal amphotericin B followed by itraconazole was the primary therapeutic regimen. Overall mortality was 14.2%. Histoplasmosis remains underdiagnosed in children due to its heterogeneous presentation. Maintaining a high index of suspicion and evaluating epidemiological risk factors are essential, especially in immunocompromised hosts, to prevent diagnostic delays and severe complications such as hemophagocytic lymphohistiocytosis or central nervous system involvement.