Bacteriology of the Middle Meatus in Chronic Rhinosinusitis with and without Polyposis

There are only limited data in the literature, and none specifically from the Middle East, on the pathogenic bacteria in chronic rhinosinusitis (CRS) as opposed to healthy nasal cavities and their association with disease severity. The present study was conducted in the department of head and neck surgery of a tertiary medical center. Middle meatal swabs were taken preoperatively from patients with CRS with nasal polyposis (CRSwNP) (n = 60), CRS without nasal polyposis (CRSsNP) (n = 50), and control patients with septal deviation (n = 26) or no nasal abnormalities (n = 27). Culture findings were compared among the groups and correlated with CRS severity. Positive pathogenic culture rates were 78% in the CRSwNP group and 64% in the CRSsNP group. Twenty pathogenic bacterial species were identified; the most common was Staphylococcus aureus (27%). The most common Gram-negative isolate was Citrobacter spp. (17%). Gram-negative species were significantly more prevalent in the CRSwNP group than the others. Mean Lund-Mackay scores were 12.8 in the CRSwNP group and 6.9 in the CRSsNP group, and were unrelated to the culture findings. Positive culture rates were significantly higher in the septal deviation (54%) than the nasal healthy group (26%), although both values were significantly lower than in the CRS groups. In conclusion, patients with CRS have higher rates of bacterial isolates than patients without CRS. CRSwNP is associated with more Gram-negative bacteria than CRSsNP, regardless of disease severity. The relatively high positive culture rate in patients with septal deviation merits investigation.