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OR I G I NAL ART I CLE
Investigation of bacterial repopulation a er sinus surgery and perioperative
antibiotics
Leah J. Hauser, MD
1
, Diana Ir, BS
2
, Todd T. Kingdom, MD
1
, Charles E. Robertson, PhD
3,4,5
,
Daniel N. Frank, PhD
2,3
and Vijay R. Ramakrishnan, MD
1
Background:
Endoscopic sinus surgery (ESS) enjoys high
success rates, but repopulation with pathogenic bacteria
is 1 of the hallmarks of poorer outcomes. There are many
hypothesized sources of repopulating bacteria; however,
this process remains largely unexplored. This study exam-
ined changes in the sinus microbiome a er ESS and medi-
cal therapies to identify potential sources for postsurgical
microbial repopulation.
Methods:
Samples from the anterior nares, ethmoid sinus,
and nasopharynx were taken at the time of surgery from 13
subjects undergoing ESS for chronic rhinosinusitis (CRS).
Patients were treated postoperatively with 2 weeks of oral
antibiotics and saline rinses. The ethmoid sinus was sam-
pled at 2 and 6 weeks postoperatively; microbiota were
characterized using quantitative polymerase chain reaction
(qPCR) and 16S ribosomal RNA (rRNA) gene sequencing.
The Morisita-Horn beta-diversity index (M-H) was used to
compare similarity between samples.
Results:
The bacterial burden of the ethmoid was higher
2 weeks postoperatively than 6 weeks postoperatively (
p
=
0.01). The 6-week samples most closely represented the an-
terior nares and ethmoid at surgery (M-H
=
0.58 and 0.59,
respectively), and were least similar to the nasopharynx (M-
H
=
0.28). Principal coordinates analysis (PCoA) plots illus-
trate that the ethmoid microbiota temporarily shi ed af-
ter surgery and antibiotics but returned toward baseline in
many subjects.
Conclusion:
Bacterial communities colonizing the ethmoid
6 weeks postoperatively were most similar to anterior nasal
cavity and pretreatment sinus microbial profiles, indicating
a high degree of resilience in the sinonasal microbiome of
most subjects. Interestingly, surgery and postoperative an-
tibiotic therapy does not appear to reduce bacterial bur-
den, but rather, shi s the microbial consortia.
C
2015 ARS-
AAOA, LLC.
Key Words:
sinusitis; chronic rhinosinusitis; bacteria; microbiome; py-
rosequencing; bacterial repopulation
How to Cite this Article
:
Hauser LJ, Ir D, Kingdom TT, Robertson CE, Frank DN, Ra-
makrishnan VR. Investigation of bacterial repopulation af-
ter sinus surgery and perioperative antibiotics.
Int Forum
Allergy Rhinol.
2016;6:34–40.
1
Department of Otolaryngology–Head and Neck Surgery, University of
Colorado, Boulder, CO;
2
Division of Infectious Diseases, University of
Colorado, Boulder, CO;
3
The Microbiome Research Consortium,
University of Colorado, Aurora, CO;
4
Department of Biostatistics and
Informatics, University of Colorado, Boulder, CO;
5
Department of
Molecular, Cellular, and Developmental Biology, University of
Colorado, Boulder, CO
Correspondence to: Vijay R. Ramakrishnan, MD, Department of
Otolaryngology–Head and Neck Surgery, University of Colorado, 12631 E.
17th Ave, B-205, Boulder, CO 80045; e-mail:
vijay.ramakrishnan@ucdenver.eduFunding sources for the study: NeilMed Pharmaceuticals; University of
Colorado, Department of Otolaryngology.
Potential conflict of interest: None provided.
Presented to the ARS at the Combined Otolaryngology Spring Meetings
(COSM) on April 24, 2015, in Boston, MA.
Received: 1 April 2015; Revised: 10 July 2015; Accepted: 21 July 2015
C
hronic rhinosinusitis (CRS) is a chronic inflammatory
disorder of the paranasal sinuses, in which bacteria
may play some role.
1
Surgical therapy and medical treat-
ment in the early postoperative period are directed at im-
proving sinus ventilation, eradicating pathogenic bacteria,
and perhaps restoring microbiome disturbances to a healthy
state. Although 72% to 90% of patients have good post-
operative outcomes,
2–5
a subset of patients have continued
disease requiring further medical and surgical therapy.
Repopulation with pathogenic bacteria is 1 of the hall-
marks of a poor outcome after endoscopic sinus surgery
(ESS).
6,7
Many theories have been proposed for the source
of bacterial repopulation, including persistence of bacterial
DOI: 10.1002/alr.21630
View this article online at
wileyonlinelibrary.com.International Forum of Allergy & Rhinology, Vol. 6, No. 1, January 2016
Reprinted by permission of Int Forum Allergy Rhinol. 2015; 6(11):34-40.
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