Microorganisms antibiotic sensitivity determination in urinary tract infections

Abstract

Introduction. Nowadays Urinary tract infections (UTI) are considered to be the most common bacterial infections. Escherichia coli is the most frequently uropathogen. Other microorganisms of the genera Enterococcus, Klebsiella, Enterobacter, Proteus, Morganella, Citrobacter, Serratia, Pseudomonas, Streptococcus, Staphylococcus, Candida are also isolated with variable frequency. In recent years there has been a decreasing tendency of the causative agents of UTI sensitivity to various antibiotics, which causes growth of an inefficiencytreatment risk. In connection with the above the investigations were carried out with the purpose to identify the actual causative agents of bacteriuria and their sensitivity to antibiotics and antifungal drugs. Materials and methods. Bacteriological examination of urine was performed at 42 patients of SI "Sytenko Institute of Spine and Joint Pathology, AMS of Ukraine" clinic. The bacteriological method for determining the number of bacteria in the test material, cultural and bacterioscopic methods for identifying microorganisms and disk-diffusion method for sensitivity of microorganisms to antibiotics determining were used.The clinical material for the study was an average portion of the morning urine or urine collected by catheter. The biological material collection and bacteriological examination was carried by quantitative method, the isolated microorganisms identification and their sensitivity to antibiotics determining was performed by standard methods in accordance with current guidelines. We used the following antibiotics group to determine the microorganisms sensitivity: penicillin, cephalosporin, karbapenems, tetracyclines, aminoglycoside, fluoroquinolones, oxazolidinones, macrolides, lincosamides, glycopeptides, antifungal antibiotics. Results and discussion. During the biological material study 55 isolates of bacterial and fungal pathogens were obtained. The microorganisms’ concentration in urine was in the range of 3,0x10⁶ CFU/ml to 3,0x10⁹ CFU/ml, and the most bacterial isolates content was equal 1,5x10⁹ CFU/ml. Among the most commonly identified microorganisms Escherichia coli and Staphylococcus spp. were often detected in 5,3x10⁸ CFU/ml concentrations. For Streptococcus spp. and Proteus mirabilis that value was 1,5x10⁹ CFU/ml; for Klebsiella pneumonia - 3,0x10⁸ CFU/ml; for Candida spp. - 3,0x10⁶ CFU/ml respectively. The most common microorganisms (which frequency of occurrence in urine was ≥ 5%) were: E. coli (14,5±4,7)%, Str. agalactiae and St. haemolyticus (10,9±4,2)%; St. aureus and Pr. mirabilis (7,3±3,5)%; St. epidermidis, Kl. pneumoniae, St. hominis,Candida spp. (5,4±3,0)%. While analyzing obtained results we concluded that meropenem was the most effective drug, 78,7% of all cultures had the sensitivity to it. The sensitivity to gatifloxacin had 73,7% of cultures; to tigecycline – 71,1% of isolates; to amikacin -67,3% of cultures; to moxifloxacin – 59,6% of isolates; to two drugs (levofloxacin and pefloxacin) - 55,8% of isolates respectively. It was found that Staphylococcus aureus appeared to be resistant to vancomycin, ampicillin, cefuroxime, cefazolin, azithromycin, linezolid. This species and St. epidermidis and St. hominis isolates were multi-drug resistant to four or more drugs from different groups. All Streptococcus agalactiae isolates were insensitive to cefuroxime. All Escherichia cultures were resistant to cefuroxime, Proteus - to cefuroxime, ampicillin and cefazolin. E. coli, Pr. mirabilis,K. pneumoniae, Ps. aeruginosa, Ac. haemolyticus had multi-drug resistance. In addition, (73,1 ± 6,1)% of all 52 bacterial isolates obtained were resistant to amoxiclav. Conclusions. 1. The most common microorganisms (which incidence in urine were ≥ 5%) are: Escherichia coli (14,5±4,7)%, Streptococcus agalactiae and Staphylococcus haemolyticus (10,9±4,2)%; Staphylococcus aureus and Proteus mirabilis (7,3±3,5)%; Staphylococcus epidermidis, Klebsiella pneumoniae, Staphylococcus hominis,Candida spp. (5,4±3,0)%. 2. The most effective antibacterial drug is meropenem. 78,7% of all isolates have sensitivity to it. The sensitivity to gatifloxacin have 73,7%; to tigecycline 71,1%; to amikacin – 67,3%, to moxifloxacin – 59,6% of cultures, to two agents (levofloxacin and pefloxacin) – 55,8% of cultures respectively. 3. 100% of the family Micrococcaceae isolates were resistant to benzylpenicillin, 95,8% - to ampicillin, 87,5% - to amoxicillin and cefuroxime, 83,3% - to azithromycin, erythromycin and lincomycin. Members of the Streptococcaceae family were resistant to cefuroxime. 100% of the family Enterobacteriaceae isolates had no sensitivity to carbenicillin, 87,5% of isolates - to cefuroxim and gentamicin, 81,2% - to amoxicillin and ampicillin, 75,0% - to cefazolin, 50,0% - to ceftriaxonum and aztreonam. 4. Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus hominis Escherichia coli, Proteus mirabilis,Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter haemolyticus isolates were multi-drug resistant.