[Current state of antibiotic resistance of pathogens causing community-acquired urinary tract infections in Russia, Belarus and Kazakhstan: results of the international multicenter study Darmis-2018].

OBJECTIVE: To study in vitro activity of antimicrobials against clinical isolates from patients with community-acquired urinary tract infections (UTIs) in different regions of Russia, Belarus and Kazakhstan in 2017-2018. MATERIALS AND METHODS: A total of 1260 isolates collectedin the Russian Federation, Belarus and Kazakhstanas a part of the international multicenter prospective epidemiological study of the dynamics of antimicrobial resistance of uropathogens causing community-acquired urinary tract infections in different subsets of patients ("DARMIS-2018") were included in the analysis. 1124 strains represented the Enterobacterales order. Uropathogenswere isolated from children and adults of both sexes of all age groups with acute (and recurrences of chronic) community-acquired UTIs including pregnant women with asymptomatic bacteriuriain 34 centers of 26 cities of Russia, Kazakhstan and Belarus in 2017-2018. RESULTS: Enterobacterales jointly comprised a total of 89,2% of all isolated bacterial pathogens (88,9% in the adult subset; 89,3% in the subset of pregnant women and 91,4% in the subset of children and adolescents under 18). The most prevalent species were Escherichia coli (69,4% in the adult subset; 73,6% in the subset of pregnant women and 77,1% in the subset of children and adolescents under 18) and Klebsiella pneumoniae (11,5% in the subset of adults; 10,4% in the subset of pregnant women and 7,1% in the subset of children and adolescents under 18 years of age). The maximum activity against E. coli among oral drugs demonstrated fosfomycin (97,9% in the adult subset; 95,9% in the subset of pregnant women and 99,1% in the subset of children and adolescents under 18) and nitrofurantoin (97,9% in adult subset; 100% in the subset of pregnant women and 96,3% in the subset of children and adolescents under 18). Out of the parenteral drugs meropenem (out of carbapenems) and amikacin showed the highest activity (99,5% and 97,7% in the adult subset; 99,5% and 99,1% in the subset of pregnant women; 100% and 97,2% in the subset of children and adolescents under 18 years of age, respectively). Ampicillin, amoxicillin/clavulanic acid and trimethoprim/sulfamethoxazole demonstrated the lowest in vitro activity against Escherichia coli (less than 80% for everypatient subset). The susceptibility of E. colito ciprofloxacin was 60,4% in the adult subset; 80,0% in the subset of pregnant women and 80,6% in the subset of children and adolescents under 18. The rate of production of extended spectrum beta-lactamases among E. coli isolates based on the results of phenotypic tests was 21,9%. CONCLUSIONS: Results of this study indicate the increase of resistance of community-acquired isolates of Enterobacterales and in particular E. coli to the most of antimicrobials in Russia, Belarus and Kazakhstan.

RESULTS OF MONITORING METALLO-BETA-LACTAMASE-PRODUCING STRAINS OF PSEUDOMONAS AERUGINOSA IN A MULTI-PROFILE HOSPITAL.

The authors present the results of long-term monitoring of metallo-beta-lactamase (MBL) producing strains of Pseudomonas aeruginosa in the Republican Hospital No 2 of Yakutsk, Russian Federation. Hospitals across Russia, as well as the rest of the world, face a rapid appearance and a virtually unchecked spread of multiresistant and panresistant nosocomial pathogens. Especially prevalent are multidrug-resistant isolates of P. aeruginosa, most often found among the patients of intensive care and intensive therapy units, as well as surgery departments. The aim of this study is to investigate the prevalence of metallo-beta-lactamase-producing strains of P. aeruginosa in a multi-profile hospital. 2,135 isolates of P. aeruginosa were studied, collected during a time span of seven years (2008-2014) from clinical specimens of hospitalised patients in acute surgery, purulent surgery, neurosurgery, otolaryngology, coloproctology departments, intensive care and intensive therapy, burn units, as well as intensive care unit for patients with acute cerebrovascular accidents and coronary care unit. Strains were identified and re-identified using established methods, NEFERMtest 24 (MICROLATEST) biochemical microtest and API (bioMerieux) test systems were used. For all carbapenem-resistant strains a phenotype screening for MBL was performed using the double-disks method with EDTA. In order to identify VIM-type and IMP-type MBL genes a real-time multiplex polymerase chain reaction was used. Among the investigated strains the largest number of P. aeruginosa - 35.6% (761 isolates) was found in patients at intensive care and intensive therapy units. Clonal expansion of extensively drug-resistant strain P. aeruginosa ST235 (VIM-2) was determined, the resistance mechanism of which is connected to MBL. Sensitivity determination of MBL-producing isolates of P. aeruginosa has shown that isolated strains have a high level of resistance (100%) to all tested antibacterial agents: piperacillin, piperacillin-tazobactam, ceftazidime, cefepime, cefoperazone-sulbactam, aztreonam, imipenem, meropenem, doripenem, gentamicin, netilmicin, amikacin, ciprofloxacin, levofloxacin, fosfomicin.

First detection of VIM-4 metallo-ß-lactamase-producing Escherichia coli in Russia.

An Escherichia coli isolate co-producing VIM-4 metallo-ß-lactamase and CTX-M-15 extended spectrum ß-lactamase was recovered from the urine of a patient with head trauma in Moscow, Russia. The bla(VIM-4) and bla(CTX-M-15) genes were carried, respectively, by transmissible plasmids of IncW and IncI1 groups. The nucleotide sequence of the VIM-4-encoding integron was nearly identical to that of In416, which represent a large group of structurally related integrons previously found in Enterobacteriaceae all around the Mediterranean basin. This is the first report of a metallo-ß-lactamase-producing E. coli in Russia.

A MALDI TOF MS-based minisequencing method for rapid detection of TEM-type extended-spectrum beta-lactamases in clinical strains of Enterobacteriaceae.

A minisequencing method based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) was developed for rapid identification of single nucleotide polymorphisms at bla(TEM) gene codons 104, 164 and 238 associated with extended-spectrum activity on TEM-type beta-lactamases. The method was validated by testing the Escherichia coli and Klebsiella pneumoniae strains possessing the known bla(TEM) gene sequences.

Detection of sequence variation in PCR-amplified fragments of omp2 gene from three species of the family Chlamydiaceae using agarose gel electrophoresis containing bisbenzimide-PEG.

A simple technique providing a means for rapid genetic differentiation of chlamydial strains is described. The technique is based on a single-step sequence-specific separation of PCR-amplified DNA fragments by electrophoresis in an agarose gel containing a DNA ligand - bisbenzimide-PEG. A hypervariable region at the 5' end of the omp2 gene of Chlamydiaceae species encoding the 60-kDa cysteine-rich outer membrane protein was selected as a target for PCR. The appropriate fragments were amplified from strains of Chlamydia trachomatis, Chlamydophila pneumoniae, and Chlamydophila psittaci, and the PCR products originating from different species were electrophoretically separated in the presence of the DNA ligand. We therefore demonstrated that PCR with a single pair of primers followed by simple agarose gel electrophoresis with bisbenzimide-PEG can be applied to the differentiation of three members of the family Chlamydiaceae which are commonly recognized as human pathogens.