Chemotherapy Disrupts Oral Microbiome in Children, Predicting Mucositis Risk

Oral mucositis remains one of the most debilitating complications of pediatric cancer treatment, affecting quality of life and treatment outcomes. Understanding how chemotherapy disrupts the oral microbiome could lead to better prevention strategies and personalized care approaches.

This double-blind randomized trial followed 34 children aged 2-18 years with solid or blood cancers undergoing chemotherapy. Researchers collected mucosal swabs before and after treatment, analyzing bacterial DNA using advanced 16S rRNA sequencing. Patients received either Caphosol (calcium phosphate rinse) or saline mouth rinses in randomized order during two treatment cycles.

Chemotherapy significantly altered the oral bacterial ecosystem. While no life-threatening mucositis cases occurred, three patients developed mild to severe oral lesions. Crucially, the study identified distinct microbial signatures associated with mucositis risk. Patients who remained lesion-free showed higher Bergeyella bacteria before treatment and increased Alloprevotella afterward, compared to those who developed complications.

Patients developing mucositis harbored specific bacterial profiles including Stenotrophomonas, Leptotrichia, Serratia, and Capnocytophaga species. Additionally, the Caphosol group showed higher levels of Burkholderia-related bacteria compared to saline users, suggesting treatment-specific microbial responses.

These findings represent a significant step toward personalized pediatric oncology care. By identifying microbial markers that predict mucositis risk, clinicians could potentially intervene earlier with targeted preventive strategies. The research also highlights how different mouth rinse treatments may influence bacterial communities differently, informing treatment selection. However, the small sample size and single-center design limit broader applicability, warranting larger multicenter studies to validate these promising biomarkers.