Five-year cumulative antimicrobial resistance profiles of respiratory tract isolates in a tertiary care center (2021–2025)

Year 2026, Volume: 8 Issue: 2, 194 - 198, 10.03.2026

Abdurrahman Gülmez , Mehmet Akif Durmuş

https://doi.org/10.38053/acmj.1847704

https://izlik.org/JA43WA86PS

Abstract

Aims: The success of empirical treatment for Streptococcus pneumoniae (S. pneumoniae), Haemophilus influenzae (H. influenzae),and Moraxella catarrhalis (M. catarrhalis) depends on current antimicrobial resistance (AMR) profiles. This study aimed to determine the five-year cumulative AMR profiles and trends in a tertiary care center.
Methods: Strains isolated from lower respiratory tract samples between 2021 and 2025 were retrospectively analyzed. Identification was performed via MALDI-TOF MS; susceptibilities were determined by the Phoenix M50 system and disk diffusion according to EUCAST criteria. Cumulative data were analyzed following KLİMUD guidelines, including only the first isolate from each patient.
Results: A total of 1870 isolates (1075 H. influenzae, 501 S. pneumoniae, 294 M. catarrhalis) were evaluated. High resistance rates were found in S. pneumoniae for erythromycin (47.9%), penicillin (45.2%), and tetracycline (45.2%), while no resistance to vancomycin or meropenem was detected. In H. influenzae, resistance rates were 37.0% for ampicillin, 37.9% for trimethoprim sulfamethoxazole, and 12.4% for amoxicillin-clavulanate. M. catarrhalis exhibited low resistance rate to amoxicillin-clavulanate (2.5%) and macrolides (0.7%).
Conclusion: The study demonstrates that resistance to conventional oral antibiotics has reached critical levels in S. pneumoniae and H. influenzae, while Moraxella catarrhalis has maintained a relatively susceptible profile. Tailoring empirical treatment protocols based on local cumulative antibiogram data is essential.

Keywords

Microbial sensitivity tests , drug resistance , Streptococcus pneumoniae , Haemophilus influenzae , Moraxella catarrhalis

Ethical Statement

This research has received approval from the non-interventional ethics committees of Istanbul Basaksehir Cam and Sakura City Hospital with decision number KAEK/17.12.2025.462.

References

• Haider A, Spurling BC, Sánchez-Manso JC. Lewy Body Dementia. In: StatPearls. Treasure Island (FL): StatPearls 2023.
• Torumkuney D, Aktas Z, Unal S, van Hasselt J, Seyhun Y, Keles N. Country data on AMR in Türkiye in the context of community-acquired respiratory tract infections: links between antibiotic susceptibility, local and international antibiotic prescribing guidelines, access to medicine and clinical outcome. J Antimicrob Chemother. 2022;77(1):i51-i60. doi:10.1093/jac/dkac217.
• Zhao C, Yang S, Zhang F, et al. Antimicrobial resistance trends of the most common causative pathogens associated with community-acquired respiratory infections in China: 2009-2018. Infect Drug Resist. 2022;15:5069-5083. doi:10.2147/idr.S374805
• Testing ECoAS. EUCAST-clinical breakpoints and interpretation: EUCAST/ESCMID
• Gülay Z. Turkish Society of Clinical Microbiology (KLİMUD). Guideline for the Analysis and Presentation of Antimicrobial Susceptibility Data. 2019;1.
• Zarakolu P, Soyletir G, Gur D, Unal S. Antimicrobial resistance patterns of respiratory pathogens: a local report from Turkey. Clin Microbiol Infect. 2003;9(12):1257-1258. doi:10.1111/j.1469-0691.2003.00780.x
• Republic of Türkiye Ministry of Health, General Directorate of Public Health. National Antimicrobial Resistance Surveillance Network (UAMDS) Annual Report 2022–2023. Ankara, Türkiye; 2025.
• Gür D, Ozalp M, Sümerkan B, et al. Prevalence of antimicrobial resistance in Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Streptococcus pyogenes: results of a multicentre study in Turkey. Int J Antimicrob Agents. 2002;19(3):207-211. doi:10.1016/s0924-8579(02)00003-1
• Sener B, Tunçkanat F, Ulusoy S, et al. A survey of antibiotic resistance in Streptococcus pneumoniae and Haemophilus influenzae in Turkey, 2004 2005. J Antimicrob Chemother. 2007;60(3):587-593. doi:10.1093/jac/dkm232
• Hascelik G, Sancak B, Kasikci M. A twenty years’ results of the antimicrobial resistance profile and multidrug resistance trend of invasive Streptococcus pneumoniae isolates recovered from adult patients in Turkey: a literature review. Indian J Med Microbiology. 2022; 40(3):342-346. doi:10.1016/j.ijmmb.2022.06.004
• Gür H, Hazırolan G. Haemophilus influenza suşlarının antibiyotik duyarlılık profillerinin ve Beta-Laktamaz aktivitesinin araştırılması. ANKEM Dergisi. 2020;34(1):18-24. doi:10.5222/ankem.2020.018
• Yagci A, Ilki A, Akbenlioglu C, et al. Surveillance of Haemophilus influenzae among respiratory tract samples of Turkish children. Int J Antimicrob Agents. 2003;22(5):548-550. doi:10.1016/s0924-8579(03)00242-5
• Kuvat N, Nazik H, Berkiten R, Öngen B. TEM-1 and ROB-1 presence and antimicrobial resistance in Haemophilus influenzae strains, Istanbul, Turkey. Southeast Asian J Trop Med Public Health. 2015;46(2):254-261.
• Gonullu N, Catal F, Kucukbasmaci O, Ozdemir S, Torun MM, Berkiten R. Comparison of in vitro activities of tigecycline with other antimicrobial agents against Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis in two university hospitals in Istanbul, Turkey. Chemotherapy. 2009;55(3):161-167. doi:10.1159/000214144
• Berkiten R. Türkiye’de Haemophilus influenzae: Beta-laktamaz pozitifliği ve antibiyotiklere direnç (1987–2002). ANKEM Dergisi. 2004; 18(1):53-60.
• Kılıç H, Akyol S, Parkan ÕM, Dinç G, Sav H, Aydemir G. Molecular characterization and antibiotic susceptibility of Haemophilus influenzae clinical isolates. Infez Med. 2017;25(1):27-32.
• Uskudar Guclu A, Altay Kocak A, Akcil Ok M, Tutluoglu B, Basustaoglu AC. Antibacterial resistance in lower respiratory tract bacterial pathogens: a multicenter analysis from Turkey. J Infect Dev Ctries. 2021; 15(2):254-262. doi:10.3855/jidc.12599.