High co-infection burden and ICU-specific pathogen profiles in pediatric Candida albicans respiratory infections: a large-scale tNGS analysis.

BACKGROUND

Candida albicans is a significant opportunistic pathogen in pediatric respiratory infections, yet systematic analyses of its role in hospitalized children remain scarce. This study evaluates the prevalence, clinical profiles, and outcomes of C. albicans-associated respiratory infections in this population.

METHODS

From April 2021 to December 2024, 10,310 pediatric inpatients with respiratory infections at Guangxi Zhuang Autonomous Region Maternal and Child Health Hospital underwent pathogen screening via targeted next-generation sequencing (tNGS).

RESULTS

C. albicans was detected in 5.0% (511/10,310), with detection rates varying by specimen: highest in sputum (10.3%), followed by bronchoalveolar lavage fluid (8.8%), and minimal in throat swabs (0.3%). Co-infections occurred in 99.0% (506/511), predominantly involving Mycoplasma pneumoniae (189), Haemophilus influenzae (174), and Rhinovirus (169). ICU patients (6.3%) demonstrated elevated inflammatory markers (PCT: 0.31 vs. 0.08 ng/mL; D-dimer: 795 vs. 360 ng/mL FEU; P < 0.001), prolonged hospitalization (median 17 vs. 7 days, P < 0.001), and distinct pathogens (Acinetobacter baumannii vs. M. pneumoniae in non-ICU). 51.7% and 35.4% of the children experienced respiratory and other systemic complications, respectively. Among the 511 children diagnosed with C. albicans infection, 32 (6.3%) required ICU admission for monitoring. The median duration of hospitalization for these 511 children was 7 days. Of these, 482 (94.3%) recovered and were discharged following treatment, while 26 (5.0%) had family members who requested voluntary discharge due to unsatisfactory outcomes or other reasons. Unfortunately, 3 children (0.6%) died despite receiving intensive medical treatment.

CONCLUSION

This large-scale tNGS-based study addresses critical knowledge gaps, revealing ICU-specific pathogen profiles (A. baumannii), high co-infection burdens (99.0%), and complications linked to prematurity/immunodeficiency. The predominance of lower respiratory tract involvement (sputum/BALF positivity) underscores the need for specimen-selective diagnostics. Findings advocate for optimized tNGS protocols, ICU-tailored antimicrobial strategies, and early interventions in high-risk subgroups to reduce morbidity (e.g., sepsis risk) and socioeconomic burdens.