Lower airway infection is a major cause of morbidity and mortality in patients with cystic fibrosis. It is currently unknown if the infection of the upper airway can cause exacerbation of lower respiratory tract infection. This study aimed to determine the microbiological profile of the anterior paranasal sinuses outflow tract (middle meatus) of cystic fibrosis outpatients. The microbiological profile was defined using endoscopically directed middle meatal cultures. Paired middle meatal and sputum specimens were collected from 56 outpatients for aerobic cultures. A semi-quantitative leukocyte count of the middle meatal samples was performed. The median age of patients was nine years (3-20 years). Staphylococcus aureus (37%), Staphylococcuscoagulase-negative (25%), Neisseriac (14%), Pseudomonas aeruginosa (11%), andStreptococcus pneumoniae (7%) were the most prevalent microorganisms in the middle meatal cultures. Using the middle meatal leukocyte count, 16 out of 54 patients (29.6%) presented sinus infection. The most frequently identified pathogens in patients with sinus infections wereStaphylococcus aureus (10 patients), Pseudomonas aeruginosa (4 patients), andStreptococcus pneumoniae (3 patients). Agreement of paired middle meatal and sputum cultures was significantly higher among patients with infection in middle meatal (69%). The most common middle meatal pathogens were the typical cystic fibrosis spectrum. This suggests the potential for participating in post-nasal lower airway seeding.

Respiratory infection is very common in patients suffering from cystic fibrosis (CF). However, the antimicrobial resistance rate of isolates from CF patients is not often documented. In this study, 279 respiratory specimens of 146 patients were prospectively collected from July to December 2006. Microbiological cultures and antimicrobial susceptibility tests of the most frequently isolated bacteria were performed. Sputum and oropharyngeal swabs were processed for culture. During the study period, 50% of the patients harbored Staphylococcus aureus, 35% Pseudomonas aeruginosa, 4.7% Haemophilus influenzae. Methicillin resistant S. aureus (MRSA) were detected in 8 (6%) patients; ESBL and MBL-producing P. aeruginosa were not identified in these patients. The detection of MRSA in CF patients confirms that antimicrobial resistance patterns should be always kept under surveillance. Moreover, hygiene regulations in CF clinics should prevent a further spread of resistant bacterial strains.