Distribution of Microorganisms, Antibiotic Resistance, and Clinical Outcomes in Chronic Suppurative Otitis Media

Abstract

Objective The aim of this study was to evaluate the distribution of microorganisms isolated from patients with chronic suppurative otitis media (CSOM), their antibiotic susceptibility patterns, and their association with clinical characteristics. Materials and Methods This study was designed as a retrospective analysis of prospectively collected data from 120 patients diagnosed with CSOM. Ear discharge samples were collected and subjected to microbiological analysis. The isolated microorganisms, antibiotic susceptibility profiles, treatment modalities, treatment duration, presence of cholesteatoma, and degree of hearing loss were recorded. Statistical analysis was performed using the chi-square test for categorical variables and the independent samples t-test for continuous variables. Results The most frequently isolated microorganism was Pseudomonas aeruginosa (38.3%), followed by Staphylococcus aureus (31.7%). Among Staphylococcus aureus isolates, 28.9% were identified as methicillin-resistant (MRSA), while multidrug resistance (MDR) was detected in 41.3% of Pseudomonas aeruginosa isolates. A significant association was found between the presence of cholesteatoma and advanced hearing loss (p = 0.021). The mean treatment duration was significantly longer in patients with resistant microorganisms (26.8 ± 8.1 days) compared to those with susceptible strains (20.4 ± 6.9 days) (p = 0.018). Conclusion Pseudomonas aeruginosa and Staphylococcus aureus are the most common pathogens in CSOM, and antibiotic resistance significantly affects the clinical course and treatment duration. Therefore, tailoring treatment based on culture and antibiogram results may provide a more effective and rational therapeutic approach.

Keywords

• Chronic suppurative otitis media
• antibiotic resistance
• culture
• Pseudomonas aeruginosa
• Staphylococcus aureus

Kronik Süpüratif Otitis Media Hastalarında Mikrobiyal Profil, Antibiyotik Direnci ve Klinik İlişkiler

Abstract

Amaç Bu çalışmanın amacı, kronik süpüratif otitis media (KSOM) hastalarında izole edilen mikroorganizmaların dağılımını, antibiyotik duyarlılıklarını ve bu bulguların klinik özelliklerle ilişkisini değerlendirmektir. Gereç ve Yöntem Bu çalışma, KSOM tanısı almış 120 hastaya ait prospektif olarak toplanmış verilerin retrospektif analizi olarak planlandı. Hastalardan alınan kulak akıntısı örnekleri mikrobiyolojik olarak incelendi. İzole edilen mikroorganizmalar, antibiyotik duyarlılık profilleri, uygulanan tedavi, tedavi süresi, kolesteatom varlığı ve işitme kaybı derecesi kaydedildi. İstatistiksel analizde kategorik değişkenler için Ki-kare testi, sürekli değişkenler için bağımsız örneklem t-testi kullanıldı. Bulgular En sık izole edilen mikroorganizma Pseudomonas aeruginosa (%38,3) olup, bunu Staphylococcus aureus (%31,7) izledi. Staphylococcus aureus izolatlarının %28,9’u metisiline dirençli (MRSA) olarak saptanırken, Pseudomonas aeruginosa izolatlarının %41,3’ünde çoklu ilaç direnci (MDR) tespit edildi. Kolesteatom varlığı ile ileri derecede işitme kaybı arasında anlamlı ilişki bulundu (p=0,021). Dirençli mikroorganizma saptanan hastalarda ortalama tedavi süresi (26,8 ± 8,1 gün), duyarlı mikroorganizma saptanan hastalara (20,4 ± 6,9 gün) göre anlamlı derecede daha uzun bulundu (p=0,018). Sonuç KSOM hastalarında en sık etken mikroorganizmalar Pseudomonas aeruginosa ve Staphylococcus aureus olup, antibiyotik direnci klinik seyri ve tedavi süresini anlamlı şekilde etkilemektedir. Bu nedenle tedavinin kültür ve antibiyogram sonuçlarına göre düzenlenmesi, daha etkili ve rasyonel bir yaklaşım sağlayacaktır.

Keywords

• Kronik süpüratif otitis media
• antibiyotik direnci
• kültür
• Pseudomonas aeruginosa
• Staphylococcus aureus

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