Background: Although the pathogenesis of cystic fibrosis (CF) and fungal rhinosinusitis (FRS) has been widely investigated, the relationship of these diseases is not revealed yet. The aim of this study was to evaluate the new methodology for detection of fungi in the sinuses of CF patients with FRS, to assess the association of mycobiota of the paranasal sinus and the lower airways of patients with CF and to determine the performance of a functional endoscopic surgery of sinuses (FESS) to clinical symptoms and mycobiota of lower and upper airways.
Methodology: The prospective study with 38 CF patients was conducted between January and December 2016. After mycological analyses CF patients were divided into two groups: (1) patients with confirmed fungal presence in sinuses (FRS group) and (2) patients without fungi in sinuses (non-FRS group). The study design included: 1) history data; 2) subjective assessment of severity of chronic rhinosinusitis (CRS) by sinonasal outcome test (SNOT-22); 3) objective assessment of severity of CRS by anterior rhinoscopy; 4) CT imaging of sinuses; 5) mycological examinations of sinonasal aspirate and sputum (before FESS and 3 months after FESS) and 6) functional endoscopic surgery of sinuses (FESS). Subjective and objective assessments of diseases and sinonasal mycological examinations were done before and 3 months after FESS.
Results: Our study revealed: (i) 64.2% of CF patients had CRS; (ii) fungal presence in sinonasal aspirate was confirmed in 42% patients (FRS group); (iii) patients with FRS had more severe form of CRS (75.4%) comparing to non-FRS group (p=0.004); (iv) patients with CF and FRS had statistically more complications of CF (p=0.024) and worsen response to therapy (p=0.03) then non-FRS group; (v) all patients from FRS group underwent FESS; 91% of these patients had improvement of clinical symptoms 3 months after FESS; (vi) fungal presence was confirmed in sputum of 64% patients with CF, and in 91% patients from FRS group; (vii) the most commonly isolated species were Aspergillus fumigatus (57%) and A. flavus (26%) from sinonasal aspirate and A. fumigatus (61%), Alternaria alternata (21%) and A. flavus (12%) from sputum; (viii) 3 months after FESS, fungal presence was confirmed only in sinonasal aspirate of 7% CF patients and in sputum of 18% patients with CF (p=0.009 and p=0.01; respectively).
Conclusions: This is the first study that investigates the association of fungal presence in sinuses and sputum of CF patients, and its correlation with clinical findings. There is the important correlation between pulmonary and sinus pathogens in CF patients. Subjective and objective clinical symptoms of patients with CF were significantly decreased after FESS. This inseparable connection between fungal diseases of lower and upper airways should be considered when treating these infections in CF patients. A huge amount of fungal spores in the air is the threat for the development of fungal airway diseases and early detection of fungi in the sinuses of these patients could decrease complications of CF and prevent the development of invasive fungal diseases.

Eradication of fungi from sinuses helps in improvement of lower respiratory tract’s clinical symptoms in children with cystic fibrosis