Importance of bacteriology in upper airways of patients with Cystic Fibrosis

Recently the influence of the upper airways (UAW) on the general health of a patient with Cystic Fibrosis (CF) has been acknowledged. Surprisingly the microbiology of the upper compartment of the airways receives barely any attention in the treatment of CF. The aim of the present study was to investigate the microbiology of the upper airways in adult patients with CF, to correlate these findings with cultures from the lower airways (LAW) and with clinical characteristics.

In this cross-sectional study bacteriological and clinical data were gathered from 104 adult patients with CF. UAW samples for culture were collected by nasal lavage and middle meatal swabs; LAW cultures were performed on expectorated sputum or cough swabs. Each patient performed the Rhinosinusitis Outcome Measure (RSOM-31).

In 72 patients (69.2%) UAW cultures yielded microorganisms other than normal nasal flora and in 50 patients (48.1%) Pseudomonas aeruginosa grew from the UAW cultures. Similarity between UAW and LAW cultures was determined in 50.0% of these 72 patients. In 3 patients P. aeruginosa was cultured from the UAW after successful eradication of P. aeruginosa from the LAW. P. aeruginosa in the UAW did not influence symptoms of sinonasal disease compared to other microorganisms.

Comparison of UAW and LAW cultures in adult patients with CF showed one or more concordant microorganism in 50.0% of the patients. P. aeruginosa was most frequently cultured from the UAW. P. aeruginosa can be cultured from the UAW after eradication therapy which may suggest persistence of P. aeruginosa in the UAW. We feel this is may be a motive to include the UAW in eradication therapy in Cystic Fibrosis.