Opportunistic Pathogens in Patients with Urinary Tract Infection

Abstract

Introduction: Urinary tract infections (UTIs) remain one of the most important problems of modern urology and medicine. Infections bring great discomfort and significantly reduce the quality of life. UTIs rank second after respiratory tract infections in outpatients. The most common pathogen of UTI are E.coli. The study of the etiology of UTI has great clinical and epidemiological importance in routine practice. Objective: To assess the etiological significance of pathogens in the occurrence of urinary tract infections in the Karaganda region of Kazakhstan. Methods: A total of 2378 patients presenting UTIs were enrolled and each provided a urine sample. The study was carried out in the Clinical Microbiology Laboratory MediTEC-NS between 2 January and 29 December 2018. Identification of isolated microorganisms was carried out on a WalkAway 96 Plus microbiological analyzer, Microscan model manufactured by Beckman Coulter (USA). Statistical Analysis was performed using the STATISTICA-6 package. Results: Out of 2378 patients a total of 1177 (49,5%) urine samples tested positive by culture test. From these samples, 1356 strains of microorganisms were isolated, of which 84.79% were monoculture and 21% were of a mixed culture. Gram-positive bacteria 690 (50, 88%), Gram-negative bacteria 630 (46, 46%), and Candida 36 (2.65%) were identified. Gram-negative rods were represented by Enterobacterales 557 (88.41%) and non-fermenting bacteria 73 (11.59%). In the Enterobacterales group included Escherichia coli 371 (66.61%) of which 108 (29,1%) ESBL strains. The next etiologically significant uropathogens were Klebsiella- 99 (17, 77%), Enterobacter-36 (6,46%) and Proteus-32 (8,09). K.pneumoniae prevailed in comparison with other Klebsiella spp. ESBL producing was 34 (57, 6%) out of 59 K.pneumoniae isolates. Gram-negative non-fermenting rod were represented by Acinetobacter spp-34 (46.57%) and Pseudomonas spp 31 (42.47%). Of 34 Acinetobacter spp. isolates 22 (64.7%) were identified as Acinetobacter lwoffii. Among the gram-positive pathogens of UTI, Staphylococcus spp prevailed - 411 (59.57%), followed by Enterococcus spp 197 (28.55%) and Streptococcus spp 81 (11.73%). Coagulase-negative staphylococci 381 (92,7%) isolates out of total 411 staphylococcal isolates. Staphylococcus epidermidis 245 (59,61%) and Staphylococcus haemolyticus 81 (21,17%) were the most frequent isolated coagulase-negative staphylococci. Of 411 staphylococcal isolates, 182 (44.28%) were MRS Conclusion: We found that UTIs among our study population were predominantly caused by ten opportunistic pathogens. The most common uropathogens with a frequency of 66.9% were E. coli- 30.53%, S. epidermidis -20.16%, and Enterococcus spp. -16.21%. Frequently isolated pathogens included Klebsiella, S. haemolyticus spp., and Streptococcus spp. which amounted to 21.98%. The distribution within the patient group was equable and ranged from 6,67% to 8,15%. Etiologically significant pathogens included Enterobacter spp., Proteus spp., Acinetobacter spp., Pseudomonas spp. These bacteria accounted for 11.11%. The distribution within the group was again equable and ranged within 2,55% to 2,96%.