Sinonasal and gastrointestinal bacterial composition and abundance are stable after 1 week of once‐daily oral antibiotic treatment for chronic rhinosinusitis

Abstract

Background: Despite the widespread prescription of antibiotics for the treatment of chronic rhinosinusitis (CRS), their efficacy remains uncertain. Limited penetration of systemic antibiotics into the sinonasal mucosa has been reported previously by this group. This study aimed to investigate the short-term effects of antibiotics on the sinus and gut microbiota as well as any relationships these had with drug distribution.Methods: Thirty subjects undergoing functional endoscopic sinus surgery for CRS were randomized to one of three groups: (1) doxycycline (100 mg daily for 7 days); (2) roxithromycin (300 mg daily for 7 days); and (3) control (no antibiotics given). Sinonasal and stool samples collected before and after treatment were analyzed using 16S ribosomal RNA (rRNA) gene-targeted amplicon sequencing and Droplet Digital polymerase chain reaction (PCR) for bacterial community composition and the quantification of bacterial DNA, respectively.Results: There were no significant major bacterial community shifts or changes to bacterial diversity and load following the treatment period in all patient groups. Non-significant trend reductions were observed in gut microbial diversity with antibiotics. For the roxithromycin group, sinonasal bacterial diversity was negatively correlated with serum drug levels and reduced overall compared to controls (p < 0.05). The relative abundance of Staphylococcus ASV129 in sinonasal samples reduced with increasing mucus doxycycline levels (p = 0.01). Conclusion:Antibiotic prescription for CRS should be further investigated because of preliminary evidence of poor sinonasal drug penetration, unproven efficacy, and the potential impact of dysbiosis in the sinuses and off-target sites. Further studies should consider distinguishing the presence of DNA from viable and nonviable bacteria.

Effect of adding probiotics to an antibiotic intervention on the human gut microbial diversity and composition: a systematic review

“…Eleven articles within the category of antibiotics only were utilized in the creation of the antibiotic section of this systematic review [4,[17][18][19][20][21][22][23][24][25][26]. Eight of the eleven selected clinical trials used some sort of randomization [4,17,19,21,22,[24][25][26], with only three being placebo-controlled [4,21,25] or blinded [21,25,26]. Total sample size ranged from 5 [20] to 103 [25] participants, whereas group sample size ranged from 3 [17] to 37 [25].…”

“…The most common utilized were vancomycin [17,18,21,23], ciprofloxacin [17,18,23], metronidazole [17,18,23] and amoxicillin [4,21,24]. The length of intervention ranged from 3 [19] to 14 [25] days, with six of the studies including a 7 day intervention period [17,18,21,23,24,26]. The reasons for prescription mainly consisted of research purposes [4,[17][18][19][20][21][22].…”

Perspectives in Therapy of Chronic Rhinosinusitis

“…Using amoxicillin-clavulanate for patients with acute exacerbation of CRS did not change the clinical course of this disease [ 88 ]. It has been suggested that short-term oral antibiotics poorly penetrate SM [ 89 ].…”

Year in review: 2021 IFAR article summary

“…Maniakas et al 7 conducted a double-blind, randomized trial demonstrating that low-dose oral azithromycin aids polyp resolution in patients with persistent polyposis despite ESS and high-volume corticosteroid irrigations. Siu et al 8 performed a randomized study of 30 patients undergoing ESS and analyzed sinonasal and stool samples using RNA sequencing. After randomization to doxycycline, roxithromycin, or no antibiotic (control), there were no significant bacterial shifts or changes in diversity or load.…”

“…conducted a double‐blind, randomized trial demonstrating that low‐dose oral azithromycin aids polyp resolution in patients with persistent polyposis despite ESS and high‐volume corticosteroid irrigations. Siu et al 8 . performed a randomized study of 30 patients undergoing ESS and analyzed sinonasal and stool samples using RNA sequencing.…”