Bacteriology of endoscopically normal maxillary sinuses

The bacteriology of maxillary sinuses with normal endoscopic findings is re ported in this study. When transantral sinoscopy was used to examine the ma xillary sinuses, the whole maxillary sinus was inspected with different-ang le endoscopes. If no lesion was seen over the whole maxillary sinus mucosa, no secretion existed in the maxillary sinus cavity, and the maxillary sinu s ostium was wide open, the maxillary sinus was considered endoscopically n ormal. The bacteriology of these endoscopically normal maxillary sinuses wa s studied by passing cotton-tipped sticks through the cannula to collect sw ab specimens. In some cases, a biopsy forceps was also passed to obtain muc osal specimens. The specimens were sent to the laboratory for aerobic and a naerobic cultures. Between July 1990 and May 1998, 83 swab and 31 mucosal s pecimens were collected from 69 patients who had not taken any antibiotic w ithin 10 days before endoscopy. The culture rates were 62.3 per cent (35/53 ) from swab specimens and 57.1 per cent (eight out of 14) from mucosal spec imens in patients with the diagnosis of chronic paranasal sinusitis, and we re 46.7 per cent (14/30) from swab specimens and 41. 2 per cent (seven out of 17) from mucosal specimens in patients without this diagnosis. This stud y shows that endoscopically normal maxillary sinuses are not sterile.