Detection of bacteria by 16S rRNA PCR and sequencing in culture-negative chronic rhinosinusitis

Current studies on the association between bacteria and chronic rhinosinusitis (CRS) have relied solely on microbiological culture, which can sometimes be negative due to prior antibiotic therapy or lack of transport media. The objective of the study was to understand whether bacteria are associated with culture-negative cases.

We investigated 20 cases of CRS undergoing functional endoscopic sinus surgery by both culture and 16S rRNA gene polymerase chain reaction (PCR) followed by sequencing. The disease severity was assessed using Sino-nasal Outcome Test-22 (SNOT-22) scoring preoperatively.

Of the 20 cases studied, only five were culture-positive. Bacteria were detected in all 15 culture-negative cases by 16S rRNA gene PCR. Sequencing indicated that Staphylococcus is the dominant group, followed by Enterobacter and Pseudomonas. In two cases, from which Pseudomonas was detected, SNOT-22 scores were above 80, indicating high disease severity.

16S rRNA gene PCR, followed by sequencing, would help the clinician understand the association between bacteria and CRS. Molecular detection and identification of bacteria would help the clinician better predict the outcome and plan further management accordingly.

NA. Laryngoscope, 128:2223-2225, 2018.