PCR analysis of nasal polyps, chronic sinusitis, and hypertrophied turbinates for DNA encoding bacterial 16S rRNA

Background: Nasal polyps are considered to result from chronic inflammation, but the initial or persisting stimulus for the inflammation is not known. A variety of bacteria and fungi have been cultured from nasal polyps, but similar to35% have sterile cultures. Previously, Mycoplasma pneumoniae-specific DNA was detected in human nasal polyps using polymerase chain reaction (PCR) techniques, suggesting M. pneumoniae as a causative agent in the etiology of nasal polyps. Methods: In this study, we tested for the presence of bacterial DNA in nasal polyps resected from 40 patients, in nasal mucosa membrane from 9 patients undergoing turbinectomy for hypertrophy, and in sinus mucosa membrane from 6 patients undergoing endoscopic surgery for chronic sinusitis. Tissue DNA was extracted and analyzed by PCR using M. pneumoniae specific primers for DNA that encode the 16S rRNA gene in 41 specimens (31 polyps, 6 turbinates, and 4 sinus), and by consensus sequence-based PCR using broad range primers for most eubacterial DNA encoding the 16S rRNA gene in 38 specimens (26 polyps, 7 turbinates, and 5 sinuses). Results: Only two samples were positive for bacterial DNA encoding 16S rRNA: Streptococcus sp. DNA was isolated from one polyp specimen and Pseudomonas aeruginosa DNA was isolated in one maxillary sinusitis specimen. No evidence of M. pneumoniae-specific DNA encoding 16S rRNA was found in any of the tissues. Conclusions: This study suggests that chronic bacterial infection is not a major component of nasal polyp etiology.