429 - Re-defining the Epidemiology of Pediatric Histoplasmosis in a Non-Endemic Area

Publication Number: 2417.429

Gabriela Rodas Cedeno, Baylor College of Medicine, Houston, TX, United States; Ankhi Dutta, Baylor College of Medicine, Houston, TX, United States; Sarah Gunter, Baylor College of Medicine, Houston, TX, United States

Background: Histoplasmosis (HP) is the most common endemic mycosis in the United States. Climate change is modifying its geographical distribution. Texas is considered an emerging endemic area; little is known about pediatric histoplasmosis (pHP) in this region. The knowledge of pHP in the non-endemic region will improve clinicians' diagnostic abilities.

Objective: The primary aim of our study was to describe the contemporary epidemiology, clinical characteristics and outcome of pHP in the historically non-endemic major urban center of Houston, Texas. We also investigated the geospatial distribution of pHP in the region.

Design/Methods: We performed an IRB-approved 15-year retrospective review of pHP at a quaternary care pediatric hospital in Houston, TX from January 2010 to October 2025. Cases were identified from electronic medical records using ICD-10 codes. Demographic, clinical, and microbiological data were obtained. We conducted a descriptive analysis of all variables and a geospatial distribution of patient locations.

Results: We identified 61 cases of pHP. Median age was 12 years (0.3-29); 35 (57.3%) were males, 77% are white and 50.8% Hispanic (Table). Thirty-seven individuals (60.6%) were immunocompetent. Only 24 (39.3%) cases had a travel history within one-year of diagnosis, the most common place being Mexico. Fourteen (22.9%) cases had bird exposures; 5 also had a travel history. The most common clinical presentation was fever (54%) and cough (34%). The most common clinical syndrome was pulmonary pHP (65%) and disseminated pHP (34%). Majority of patients (70.4%) had clinical resolution. Forty (65.5%) patients received antifungal therapy. The case fatality rate was 4.9%; all were immunocompromised. An analysis of the spatial distribution of patients showed a clustering of pHP in southwest Houston, a flood-prone area (Figure). We noted an increase in pHP between 2018 to 2020 post hurricane Harvey and in 2022 post Uri winter storm (Graph).

Conclusion(s): Children with pHP living in Houston have similar clinical characteristics to the ones described in hyperendemic areas. Both immunocompetent and immunocompromised patients are at risk. Geospatial description reveals clustering of cases in southwest Houston, a common flood prone area. Further analyses are being conducted to evaluate the effect of temperature, rainfall, and humidity on pHP in the region.

Pediatric Histoplasmosis in Urban Houston, Texas
Cases clustered in the southwest region of Houston. A known area at high risk for flooding.

Epidemiology Curve
Increase number of cases after major flooding events in Houston

Demographics and Clinical Characteristics of Pediatric Histoplasmosis in Houston
Description in percentages from our cohort on pediatric histoplasmosis