Stesura Seveso Archivio Italiano di Urologia e Andrologia 2020; 92, 2146 ORIGINAL PAPER Microorganisms and antibiotic susceptibilities isolated from urine cultures Abdullah Gul 1, Esra Gurbuz 2 1 University of Health Sciences, Bursa Yuksek Ihtisas Training and Research Hospital, Department of Urology, Bursa, Turkey; 2 Kelkit State Hospital, Department of Infectious Diseases and Clinical Microbiology, Gumushane, Turkey. Objectives: Urinary tract infection (UTI) is the second most common cause of infection among all infectious diseases at hospitals. Antibiogram results are needed to maintain treatment in patients with suspected UTI. However, empirical antibiotic treatment is initiated in patients since it takes time to obtain the results of antibi- ograms. The aim of this study was to evaluate the urine cul- ture and antibiogram results of patients who were admitted to our hospital with suspected UTI and compare the results with other studies. Methods: Urine cultures requested from the hospital informa- tion system database between January of 2018 and 2019 were analyzed. Microorganism-positive urine samples and antibi- ogram results were evaluated and included in the study. Results: Of the patients, 748 (61.8%) were female and 463 (38.2%) were male. The average age of all patients was 44.9 years. Escherichia coli was the most frequently isolated microorganisms from urine cultures (n = 828, 68.4%). Among all microorganism-positive urine samples, antibiotic resistance against Cefalexin, Fusidic acid, Ampicillin, Erythromycin, Levofloxacin, Cefuroxime Axetil, Trimethoprim/ Sulfamethoxazole, Ceftriaxone and Ciprofloxacin was 83.9%, 68.4%, 61.8%, 44.7%, 42.7%, 36.4%, 30%, 28.6% and 26.7%, respectively. Conclusions: High resistance to Cefalexin, Ampicillin, Cefuroxime, Axetil, Trimethoprim/ Sulfamethoxazole, Ceftriaxone and Ciprofloxacin, which are often preferred in empirical antibiotic selection, has been found. We believe that empirical antibiotic selection should not be overlooked in cases of UTI. Our study may help clinicians use appropriate antibi- otics for the clinical management of UTIs. KEY WORDS: Antibiotic resistance; Microorganisms; Urine culture. Submitted 18 November 2019; Accepted 19 January 2020 Summary No conflict of interest declared. DOI: 10.4081/aiua.2020.2.146 INTRODUCTION Antibiotic-resistant microorganisms are becoming wide- spread and the emergence of bacteria causing multidrug- resistant (MDR) urinary tract infection (UTI) has become a major public health problem (1, 2). UTIs are the sec- ond most common cause of infection among all infec- tious diseases at hospitals (3). Around 150 million new UTI cases develop worldwide each year, with an esti- mated treatment cost of $ 150 billion (4). The urethra is a portal for urine output, but it also allows pathogenic microorganisms to enter the urinary tract. Bacteria live in the vicinity of the urethral opening in both men and women and routinely colonize urine, but women are more likely to develop UTIs resulting from anatomical differences, hormonal effects and behavior (5, 6). Antibiograms are used to maintain treatment in patients with suspected UTIs. However, empirical antibiotic treatment is initiated in patients since it takes time to obtain the results of antibiograms. The causative agent and the selected antibiotic affect the success of the treat- ment. The choice of drug for empirical antibiotic treat- ment is very important because of antibiotic resistance. Empirical antibiotic selection should be followed at reg- ular intervals for the sensitivity results of the hospital and the region studied (7). Because the prevalence of UTI pathogens and their resistance to different antibi- otics may have changed over the years (8). Antimicrobial resistance is increasing worldwide, leading to infections that are difficult to treat and are associated with high mortality, morbidity and cost (9, 10). The aim of this study was to evaluate the urine culture and antibiogram results of patients who were admitted to our hospital with suspected UTI and compare the results with other studies. We believe that our study will help physi- cians select appropriate empirical antibiotics for the clini- cal management of UTIs. Morever, it may serve as data source for reviews and meta-analysis in future. MATERIALS AND METHODS In this study, both urine cultures and antibiogram results of 1211 patients who were admitted to urology outpa- tients clinic of Van Regional Training and Research Hospital between 2018-2019 and who were positive for urine culture were analyzed retrospectively. In the microbiolo- gy laboratory urine samples obtained for culture from mid stream by sterile urine containers were evaluated as standard with 0.01 milliliter calibrated flasks with 5% sheep blood and eosin methylene blue (EMB) agar and incubated at 37˚C for 18-24 hours. Isolated bacteria were identified by fully automated identification with antibiogram device (VITEK 2 Compact BioMerieux, France) and antibiotic susceptibility results were deter- mined. Antibiogram results were given in three groups as less sensitive, sensitive and resistant. Data were expressed as mean ± standard deviation and percentage. RESULTS Of the patients, 748 (61.8%) were female and 463 (38.2%) were male. The average age of all patients was 44.9 years. 147Archivio Italiano di Urologia e Andrologia 2020; 92, 2 Epidemiology of urinary tract infections It was 38.2 years in female patients whilst 55.8 years in male patients. Escherichia coli (E. coli) was the most fre- quently isolated microorganisms (n = 828, 68.4%) from urine cultures. Isolated microorganisms are shown in Table 1 as number and percentage. When all samples were examined, antibiotic resistance against to Cefalexin, Fusidic acid, Ampicillin, Erythromycin, Netilmicin, Levofloxacin was 83.9%, 68.4%, 61.8%, 44.7%, 43.8%, 42.7%, respectively. Also, antibiotic resistance to Cefuroxime Axetil, Cefuroxime, Cefixime, Trimethoprim/Sulfamethoxazole, Ceftriaxone, Ciprofloxacin was found to be 36.4%, 36%, 34.3%, 30%, 28.6% and 26.7%, respectively. No microorganisms were found to be resistant to Amphotericin B, Chloramphenicol, Colistin, Flucytosine and Rifampicin. However, antibiotic resistance to Meropenem, Ertapenem, Imipenem and Amikacin was found to be 0.88%, 1.14%, 1.5% and 1.6%, respectively. The data on the resistance status of antibiotics are given in Table 2 as number and percentage. Table 1. Microorganisms isolated from urine cultures. Isolated microorganisms Number Percent (%) Acinetobacter spp 2 0.17 Acinetobacter baumannii 7 0.58 Alcaligenes faecalis 1 0.08 Burkholderia cepacia 1 0.08 Candida albicans 15 1.24 Candida famata 1 0.08 Candida kefyr 2 0.17 Candida krusei 1 0.08 Candida spherica 3 0.25 Candida tropicalis 3 0.25 Citrobacter freundii 2 0.17 Citrobacter koseri 3 0.25 Enterobacter aerogenes 1 0.08 Enterobacter cloacae complex 9 0.74 Enterococcus spp 4 0.33 Enterococcus faecalis 55 4.5 Enterococcus faecium 9 0.74 Escherichia coli 828 68.4 Klebsiella spp 34 2.8 Klebsiella oxytoca 6 0.5 Klebsiella pneumoniae 87 7.2 Morganella morganii 3 0.25 Proteus spp. 4 0.33 Proteus mirabilis 21 1.73 Providencia rettgeri 4 0.33 Pseudomonas aeruginosa 24 1.2 Salmonella spp 1 0.08 Serratia fonticola 2 0.17 Serratia liquefaciens group 2 0.17 Serratia marcescens 1 0.08 Shigella sonnei 1 0.08 Staphylococcus aureus 4 0.33 Staphylococcus epidermidis 23 1.9 Staphylococcus haemolyticus 3 0.25 Staphylococcus hominis 1 0.08 Staphylococcus saprophyticus 6 0.5 Staphylococcus warneri 1 0.08 Stteptococcus spp 2 0.17 Streptococcus agalactiae 26 2.15 Streptococcus constellatus ssp pharyngis 1 0.08 Streptococcus dysgalactiae ssp equisimilis 2 0.17 Streptococcus mitis 3 0.25 Streptococcus salivarius ssp salivarius 1 0.08 Streptococcus sanguinis 1 0.08 Total 1211 100 Table 2. Antibiotic resistance rates. Antibiotic Sensitive Low Resistant Total Percent sensitive (%) Amikacin 719 178 15 912 1.6 Amoxicillin/Clavulanic Acid 13 1 7 21 33.3 Amphotericin B 15 0 0 15 0 Ampicillin 362 2 588 952 61.8 Ampicillin/Sulbactam 69 0 15 84 17.9 Aztreonam 5 18 4 27 14.8 Benzylpenicillin 29 5 3 37 8.1 Caspofungin 17 0 1 15 5.6 Cefalexin 5 0 26 31 83.9 Cefepime 25 1 3 29 10.3 Cefixime 574 0 300 874 34.3 Cefotaxime 14 0 1 5 6.7 Cefoxitin 24 769 82 875 9.4 Ceftazidime 625 68 218 911 23.9 Ceftriaxone 609 26 254 889 28.6 Cefuroxime 561 0 316 877 36 Cefuroxime Axetil 557 0 319 876 36.4 Chloramphenicol 4 0 0 4 0 Ciprofloxacin 698 46 271 1015 26.7 Clindamycin 35 0 10 45 22.2 Colistin 37 0 0 37 0 Daptomycin 53 0 3 56 5.4 Ertapenem 865 2 10 877 1.14 Erythromycin 21 0 17 38 44.7 Fluconazole 17 0 1 18 5.6 Flucytosine 17 1 18 36 0 Fosfomycin 847 0 59 906 6.5 Fusidic Acid 12 0 26 38 68.4 Gentamicin 835 5 111 951 11.7 Imipenem 873 24 14 911 1.5 Levofloxacin 46 1 35 82 42.7 Linezolid 130 0 2 132 1.5 Meropenem 891 14 8 913 0.88 Micafungin 17 0 1 18 5.6 Moxifloxacin 17 0 4 21 19 Netilmicin 18 0 14 32 43.8 Nitrofurantoin 798 1 75 874 8.6 Oxacillin 23 0 15 38 39.5 Piperacillin 15 2 10 27 37 Piperacillin/Tazobactam 682 96 124 902 13.7 Rifampicin 0 4 0 4 0 Teicoplanin 92 0 8 100 8 Tetracycline 28 0 13 41 31.7 Tigecycline 113 4 0 117 0 Tobramycin 26 0 16 42 18.8 Trimethoprim/Sulfamethoxazole 677 35 310 1022 30.3 Vancomycin 128 0 4 132 3 Vorikonazol 16 0 0 16 0 Archivio Italiano di Urologia e Andrologia 2020; 92, 2 A. Gul, E. Gurbuz 148 DISCUSSION Bacteria are the most common etiology of UTIs, account- ing for more than 95% of cases. E. coli is the most com- mon causal organism of UTIs and is responsible for more than 80% of them (11). Wright et al. reported that the rate of E. coli in urine cultures was 67% (12). Another study conducted by Akbas et al. revealed that the rate of E. coli in urine cultures was 35-80% (13). In our study, we found the rate of E. coli to be 68.4% and this rate is consistent with other studies. Microorganisms and antibiotic suscep- tibilities isolated from urine cultures may differ among countries due to usage of different agents and multifactor- ial causes. In our study, a serious resistance to Cefalexin, which is one of the most common antibiotics used for the treatment of UTIs, is observed. In a study published in 2019, Shrestha et al. reported a 60% resistance to Cefalexin (14). Ganesh and colleagues also reported 94.1% resistance to Cefalexin in their study in the same year (15). In our study, antibiotic resistance rate to Cefalexin was found to be 83.9%. All three studies point out that the rate of antibiotic resistance to Cefalexin is high. Zhanel et al. reported a resistance rate of Ampicillin to 37.7% in 2006 (16). Bryce et al. found the resistance rate to Ampicillin as 60.3% in 2016 (17). In our study, the resistance rate to Ampicillin was found to be 61.8%. Antibiotics prescribed for UTIs, most of which are caused by E. coli, have a high prevalence of resistance. When we look at the studies con- ducted worldwide, we found that Ampicillin resistance rate is the highest and Nitrofurantoin resistance rate is at very low levels. In our study, we found the Nitrofurantoin resistance rate to be 8.6%. 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BMC Infect Dis. 2019; 19:420. 16. Zhanel GG, Hisanaga TL, Laing NM, et al. Antibiotic resistance in Escherichia coli outpatient urinary isolates: final results from the North American Urinary Tract Infection Collaborative Alliance (NAUTICA). Int J Antimicrob Agents. 2006; 27:468. 17. Bryce A, Hay AD, Lane IF, et al. Global prevalence of antibiotic resistance in paediatric urinary tract infections caused by Escherichia coli and association with routine use of antibiotics in primary care: sys- tematic review and meta-analysis. BMJ. 2016; 352; i939. Correspondence Abdullah Gul, MD dr_abdullahgul@hotmail.com Bursa Training and Research Hospital Floor 2, 16310 Bursa (Turkey) ORCID 0000-0003-4002-4659 Esra Gurbuz, MD dr.inanhazan@gmail.com Kelkit State Hospital, Department of Infectious Diseases and Clinical Microbiology, Gumushane (Turkey)