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. 2023 Mar 4;12(3):517.
doi: 10.3390/antibiotics12030517.

Effect of Antibiotic Eye Drops on the Nasal Microbiome in Healthy Subjects-A Pilot Study

Clemens Nadvornik  1 , Martin Kallab  1 , Nikolaus Hommer  1 , Andreas Schlatter  1 , Theresa Stengel  1 , Gerhard Garhöfer  1 , Markus Zeitlinger  1 , Sabine Eberl  1 , Ingeborg Klymiuk  2 , Slave Trajanoski  3 , Marion Nehr  4 , Athanasios Makristathis  4 , Doreen Schmidl  1 , Alina Nussbaumer-Proell  1
Affiliations

Effect of Antibiotic Eye Drops on the Nasal Microbiome in Healthy Subjects-A Pilot Study

Clemens Nadvornik et al. Antibiotics (Basel). .

Abstract

Background: Antibiotic eye drops are frequently used in clinical practice. Due to the anatomical connection via the nasolacrimal duct, it seems possible that they have an influence on the nasal/pharyngeal microbiome. This was investigated by using two different commonly used antibiotic eye drops.

Methods: 20 subjects were randomized to four groups of five subjects receiving eye drops containing gentamicin, ciprofloxacin, or, as controls, unpreserved povidone or benzalkonium chloride-preserved povidone. Nasal and pharyngeal swabs were performed before and after the instillation period. Swabs were analyzed by Illumina next-generation sequencing (NGS)-based 16S rRNA analysis. Bacterial culture was performed on solid media, and bacterial isolates were identified to the species level by MALDI-TOF MS. Species-dependent antimicrobial susceptibility testing was performed using single isolates and pools of isolates.

Results: Bacterial richness in the nose increased numerically from 163 ± 30 to 243 ± 100 OTUs (gentamicin) and from 114 ± 17 to 144 ± 45 OTUs (ciprofloxacin). Phylogenetic diversity index (pd) of different bacterial strains in the nasal microbiome increased from 12.4 ± 1.0 to 16.9 ± 5.6 pd (gentamicin) and from 10.2 ± 1.4 to 11.8 ± 3.1 pd (ciprofloxacin). Unpreserved povidone eye drops resulted in minimal changes in bacterial counts. Preservative-containing povidone eye drops resulted in no change. A minor increase (1-2-fold) in the minimal inhibitory concentration (MIC) was observed in single streptococcal isolates.

Conclusions: Antibiotic eye drops could affect the nasal microbiome. After an instillation period of seven days, an increase in the diversity and richness of bacterial strains in the nasal microbiome was observed.

Keywords: antibiotic eye drops; ciprofloxacin; gentamicin; nasal microbiome; next-generation sequencing.

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Conflict of interest statement

None to declare. The authors declare no competing interests as well.

Figures

Figure 1
Figure 1
Microbial richness in nasal samples. Comparison of OTUs before and after treatment (Baseline: before instillation of eye drops, 1 week: after 7 days’ instillation). Sequences are clustered according to their similarity to another. Group 1 received gentamicin eye drops, group 2 received ciprofloxacin, group 3 received topical lubricants containing povidone only, group 4 received topical lubricants containing povidone and BAC.
Figure 2
Figure 2
Faith_pd in nasal samples, meaning the sum of the branch lengths of a phylogenetic tree connecting all species in the target assemblage. Comparison of the phylogenetic diversity index before and after treatment (Baseline: before instillation of eye drops, 1 week: after 7 days’ instillation). Group 1 received gentamicin eye drops, group 2 received ciprofloxacin, group 3 received topical lubricants containing povidone only, group 4 received topical lubricants containing povidone and BAC.
Figure 3
Figure 3
The change in relative abundance in % (Staphylococcus/nasal) after 1-week use of gentamicin or ciprofloxacin eye drops. Figure (A) shows the change in relative abundance in % in group 1, which received gentamicin for one week. Figure (B) shows the change in relative abundance in % in group 2, which received ciprofloxacin for one week.
Figure 4
Figure 4
The change in relative abundance in % (Streptococcus/nasal) after 1-week use of gentamicin or ciprofloxacin eye drops. Figure (A) shows the change in relative abundance in % in group 1, which received gentamicin for one week. Figure (B) shows the change in relative abundance in % in group 2, which received ciprofloxacin for one week.
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References

    1. Lukeš J., Stensvold C.R., Jirků-Pomajbíková K., Wegener Parfrey L. Are Human Intestinal Eukaryotes Beneficial or Commensals? PLoS Pathog. 2015;11:e1005039. doi: 10.1371/journal.ppat.1005039. - DOI - PMC - PubMed
    1. Quigley E.M.M., Gajula P. Recent Advances in Modulating the Microbiome. F1000Research. 2020;9:F1000 Faculty Rev-46. doi: 10.12688/f1000research.20204.1. - DOI - PMC - PubMed
    1. De Pessemier B., Grine L., Debaere M., Maes A., Paetzold B., Callewaert C. Gut-Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions. Microorganisms. 2021;9:353. doi: 10.3390/microorganisms9020353. - DOI - PMC - PubMed
    1. Meštrović T., Matijašić M., Perić M., Čipčić Paljetak H., Barešić A., Verbanac D. The Role of Gut, Vaginal, and Urinary Microbiome in Urinary Tract Infections: From Bench to Bedside. Diagnostics. 2020;11:7. doi: 10.3390/diagnostics11010007. - DOI - PMC - PubMed
    1. De Boeck I., Spacova I., Vanderveken O.M., Lebeer S. Lactic Acid Bacteria as Probiotics for the Nose? Microb. Biotechnol. 2021;14:859–869. doi: 10.1111/1751-7915.13759. - DOI - PMC - PubMed

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