Preoperative and Intraoperative Culture Results of Patients with Chronic
Otitis Media; Is Culture Swab Reliable?
Objective: The aim of this study was to analyze the culture antibiogram
results of samples obtained directly from the middle ear and/or mastoid
cells in the operating room, and from the external auditory canal in the
outpatient. Methods: This study was conducted between 2016-2018 in
Microbiology and Otorhinolaryngology Department. Swab cultures were
obtained through the external ear canal preoperatively in outpatients.
Middle ear swabs and mastoid granulation tissue were collected
intraoperatively, respectively. Demographic datas, bacterial
identifications and antibiotic susceptibilities were compared in both
groups. Results: Two hundred thirty eight patients with chronic otitis
media were enrolled in the study. Out of the 238 cases, 86 patients had
negative culture results. P. aeruginosa (n=44), Coagulase Negative
Staphylococcus (n=33), S. aureus (n=27), Proteus mirabilis (n=16) and E.
coli (n=10) were the most common grown bacteria in both groups. Most
common identified groups were Gram-positive bacteria (n=92),
non-fermenter Gram-negative bacteria (n=55) and Enterobactericeae
(n=42). Gram-positive cocci were higher in outpatient group, whereas
Enterobactericeae were higher in intraoperative group
(p<0.05). Antibiotic susceptibilities of P. aeruginosa and S.
aureus were found to be lower especially in the preoperative group (p
<0.05). Conclusion: P. aeruginosa was the most common bacteria
in both preoperative and intraoperative cultures and high ciprofloxacin
resistance of the isolates were remarkable. Although contamination is an
issue in samples collected from the external ear canal of outpatients
using cotton swabs, similar microorganisms grew in outpatient and