Differing rates of fungi in sinonasal cultures from pediatric sinusitis patients

Pediatric chronic rhinosinusitis (PCRS) is a unique clinical entity and the underlying source of inflammation is unknown. Certain subgroups, such as children with nasal polyps and cystic fibrosis (CF) sinusitis are often recalcitrant to standard medical PCRS treatments that target bacterial inflammation. Fungal infection and allergy to fungal proteins drive inflammation in other airway diseases, resulting in chronic inflammation of both the upper and lower airways. However, there is limited understanding of the role of fungi in the pathophysiology of PCRS. The objective of this study is to define the frequency of fungal infection in pediatric CRS patients, hypothesizing that certain subgroups may have more frequent positive fungal sinus cultures than other subgroups of pediatric sinusitis.

Retrospective study of patients undergoing sinus surgery at a tertiary care pediatric hospital to determine the period prevalence of positive fungal cultures in subgroups of patients.

400 children from 2012 to 2019 were included. 265 patients had surgical culture results available. Of the 52 patients with CF 11 (21%) had positive fungal sinus cultures. Similarly, 28% of the 25 patients with non-CF nasal polyps had positive cultures. Only 8.2% of 110 CRS without polyps patients had positive cultures, significantly fewer than other subgroups (X² (1, N = 240) = 17.22, p < 0.01).

Children with CF and children with nasal polyps had more frequent positive fungal cultures than children without nasal polyps having sinus surgery. This confirms that pediatric CF and pediatric CRS with polyps represent unique populations to study the impact of fungal infection in CRS. Further research is required to determine if these fungi represent colonization or contribute to the inflammatory environment of the airways.