The role of mechanically purified city sewers in the spread of antibiotic-resistant bacteria of the Enterobacteriaceae family

The aim of this study was to evaluate a degree of contribution of mechanically cleansed municipal sewage in a spread in on environment of bacteria of Enterobacteriaceae family with special regard to antibiotic resistant strains. High number of bacteria of Enterobacteriaceae family was found in 1 ml of sewage and the number of antibiotic-resistant bacteria was 0.5-50 X 10(3)/ml. Among the strains tested the resistance to more than one antibiotics was encountered. 78.3% of strains transferred antibiotic resistance to E. coli recipient strain, what indicate a participation of potentially pathogenic bacteria from Enterobacteriaceae family in a spread of antibiotic resistance in a environment.     

Antibacterial therapy of pyelonephritis in pregnant women

To determine the optimal schemes of rational antibacterial therapy of pyelonephritis gravidarum with ampicillin and cephuroxim, assays of the patient urine and studies on the pharmacokinetics of the drugs were performed. The bacteriurea levels were estimated in 264 women with Gould's method in modification of Ryabinsky and Rodoman. The causative agents of the disease were isolated from the urine of 92 pregnant women. Sensitivity of the isolates to 9 antibiotics was tested with the use of standard paper disks and the method of serial dilutions in solid media. The pharmacokinetics of ampicillin and cephuroxim in the blood and urine of 97 patients was studied for 6-8 hours after parenteral administration of the antibiotics in doses of 500 mg. Comparative analysis of the pharmacokinetic parameters of the antibiotics in the blood and urine of the patients, the antibiotic MICs for the disease causative agents and the clinical course of the disease suggests that pyelonephritis gravidarum should be treated with ampicillin and cephuroxim on doses of 500 mg injected intramuscularly 4 and 3 times a day respectively for 7-8 days in combination with antiinflammatory therapy.     

Variations in antibiotic resistance profile in Enterobacteriaceae isolated from wild Australian mammals

We carried out a retrospective analysis of 946 strains of Enterobacteriaceae isolated from wild Australian mammals between 1993 and 1997. The prevalence of resistance to fixed concentrations of 32 antimicrobial agents was determined, and the respective roles that taxonomic family of the host, state of origin and bacterial species play in defining prevalence and range of resistance were investigated. Our results demonstrated a low but widespread prevalence of antimicrobial resistance in wild isolates. Only amikacin, ciprofloxacin, meropenem and gentamicin inhibited growth in all 946 samples. There was extensive variation in the combination of antibiotics to which isolates were resistant, and multiple antibiotic resistance was common. Geographical location and host group significantly influenced the antibiotic resistance profile of an isolate, whereas bacterial species influenced both the resistance profile of an isolate and the number of antibiotics it was resistant to. The role of these factors in determining observed antibiotic resistance profiles suggests that any study measuring resistance in wild isolates should include the broadest possible range of bacterial species, host species and sampling locations. As such, this study provides an important new baseline for future measurements of antibiotic resistance in the Australian environment.     

Serodiagnosis and the immunological aspects of Proteus infection. IV. Serum antibody level and the pathomorphological and bacteriological indices in experimental mixed and monoinfections of the urinary tract

In developing the serodiagnosis of the Proteus infection of the urinary tract experimental hematogenic Proteus or Proteus-Escherichia pyelonephritis was reproduced. In this infection the time course, level and avidity of serum antibodies correlated with the isolation of the causative agents from urine samples used as seed material and with histological changes in the kidneys. The serological tests revealed high titres of H-antibodies and the presence of O-antibodies, while in cases of bacteriuria not accompanied by kidney lesions only H-antibodies in low titers were detected. The results obtained in the study of immune shifts can be used for etiological diagnosis and more exact localization of the pathological process in the urinary system.     

Therapy of urinary tract infections in patients with diabetes mellitus]

Clinical and microbiological efficacy of Cifran OD (Ranbaxy, India), a formulation with prolonged action and extended release of ciprofloxacin was studied in 22 patients with bacteriuria and lingering diabetes mellitus. Ciprofloxacin was used in doses of 500 or 1000 mg orally once a day depending on the severity of the disease singns for 2-3 weeks as etiotropic therapy and only in 2 cases with severe pyelonephritis it was used intravenously drop-wise and orally simultaneously. Twenty eight microbial strains isolated from urea of the patients were tested. The main species of the isolates belonged to the family Enterobacteriaceae. Twenty five isolates (89.3%) were susceptible to ciprofloxacin and 3 isolates (10.7%) were resistant. The clinical efficacy of ciprofloxacin was 90.9%.     

Changes in the composition of the causative agents of wound infection in emergency surgery in the period from 1967 through 1987

The composition of the causative agents of suppurations, isolated from suppurating wounds of patients hospitalized at different departments of the Sklifosovski? Emergency Aid Institute was studied. The proportion of representatives of different microbial families among more than 18,000 strains of the causative agents of wound infection was estimated. Fluctuations in the amount and structure of the agents were analyzed in different clinics over the period of 1967-1987. Under the conditions of emergency aid hospital Staphylococcus aureus proved to be the most frequent causative agent of suppurative inflammatory processes at different departments. At the same time no tendency towards an increase of the etiological role of any microbial family in the development of wound infections was noted. The incidence of different causative agents of suppurations was found to vary at different departments, depending on their specialization and season. The results of observations on the composition of the causative agents of wound infection may be used for the planning and evaluation of antiepidemic measures.     

Family and population effects on disease resistance in a reptile

Despite its importance in evolutionary biology, studies of the pattern of disease resistance in natural populations are rare. In this paper, we report patterns of infection of a viral eye disease in juvenile Swedish common lizards (Lacerta vivipara). Females were sampled at random from natural populations immediately prior to parturition with equal exposure of pathogens for all lizards once in captivity. No causative agents could be found that linked risk of disease to maternal/interfollicular transfer of pathogens. The results show that a major factor influencing offspring susceptibility is family identity, suggesting heritable variation in pathogen resistance. Our interpopulation comparison provides additional support for a link between genetics and disease resistance. Lizards in northern Sweden were not only more susceptible to the disease but were also more health compromised once infected, with relatively more reduced growth rate and increased mortality than lizards from the south. This scenario suggests that southern lizards have been under selection for resistance to this pathogen, whereas northern lizards have not, or at least not to the same degree. Thus, this study confirms the importance of genetic (family) effects on pathogen resistance with variation in this trait among natural populations.     

Microbiological control of drug resistance of causative agents in suppurative-septic infections in newborn infants

Resistance of the main causative agents of purulent septic infections such as pneumonia, meningitis, sepsis, etc. to 11 chemotherapeutic drugs was studied. The pathogens were isolated from autopsies of 203 newborns who died within 1981 to 1987. Among 2978 isolates belonging to Enterobacteriaceae (2466 strains) and Pseudomonadaceae (512 strains) which constituted 88% of all the isolates, strains with multiple resistance predominated: 90% of the strains resistant to 4 or more antibiotics, 77% of the strains resistant to 6 or more antibiotics and 48% of the strains resistant to 8 or more antibiotics. The highest number of the isolates were resistant to 8 and 9 chemotherapeutics (19 and 20%, respectively). 84% of all the isolates belonged to 4 genera: Klebsiella (34%), Escherichia (21%), Serratia (14%) and Pseudomonas (15%). They were characterized by the highest resistance spectra. In all the cases massive colonization of the intestine by the strains with multiple resistance which caused purulent septic infections was observed. The most frequent variants of the drug resistance combination were determined. In the total frequency of the isolate with multiple resistance no significant differences were detected in 1981 and thereafter. In 1986-1987 the frequency of S. marcescens strains increased 3-5 times with simultaneous broadening of their drug resistance spectra. Strains of S. marcescens and K. pneumoniae with multiple drug resistance endemic for definite hospitals were detected.     

Geographical distribution of antimicrobial resistance among Escherichia coli causing acute uncomplicated pyelonephritis in the United States

The susceptibility to 12 antimicrobial agents of 165 Escherichia coli isolates from women with acute uncomplicated pyelonephritis of mild to moderate severity was analyzed by geographic region in the US. Ampicillin, trimethoprim, and trimethoprim/sulfamethoxazole resistance exhibited a descending prevalence gradient from west to east. Composite antimicrobial resistance phenotypes also exhibited significant regional differences, with a greater prevalence of most combined resistance profiles seen in the Pacific region of the US, but with significant north-south variation for combined ampicillin/sulfisoxazole resistance. These findings suggest geographical segregation of resistant clones and/or resistance elements among uropathogenic E. coli within the US, which is relevant both to clinical practice and to understanding the basis for the current epidemic of antimicrobial resistance in E. coli.     

Conjugative transfer frequency of resistance genes from ESBL-producing Enterobacteriaceae strains isolated from patients hospitalized in pediatric wards

The aim of this study was to evaluate the transfer frequency of plasmids encoding extended-spectrum beta-lactamases (ESBLs) from clinical isolates of Enterobacteriaceae to E. coli K12 C600 recipient strain. Additionally, resistance patterns to antimicrobial drugs of the isolates as well as transconjugants were analyzed. Fifty-four clinical strains belonging to the Enterobacteriaceae family were isolated from children hospitalized in Medical University Hospital in Wroc?aw. All the strains studied were identified in automatic ATB system using ID32E tests. Besides, they were ESBL-positive as was confirmed by the double-disc synergy test (DDST). The minimal inhibitory concentration (MIC) was determined for twelve selected antibiotics and chemotherapeutics. The majority of the strains (87%) were able to transfer plasmid-mediated ESBL to E. coli K12 C600 recipient strain with a frequencies ranged from 10(-5) to 10(-1) per donor cell. All the isolates studied as well as their transconjugants were susceptible to imipenem, meropenem and norfloxacin (MIC <1mg/L). On the other hand, these strains displayed high level of resistance (MIC 512 - >1024 mg/L) to cefotaxime, ceftriaxone, gentamycin, amikacin and cotrimoxazole. Genetic markers conferring resistance to aminoglycosides and cotrimoxazole were often co-transferred to recipient strain in conjugation process.     

Shigella differentiation according to R factor affiliation with incompatibility groups taking into account antibiotic resistance spectra

The study on 198 Shigella strains isolated from dysentery patients and cultures from 3 different dysentery foci showed a possibility of intraspecies typing of the causative agents according to the R factor incompatibility groups with regard to the antibiotic resistance spectra. The procedure was most effective in defining the similarity of the strain origin from the epidemiological foci.     

In vitro transference and molecular characterization of bla TEM genes in bacteria isolated from Portuguese ready-to-eat foods

The principal aim of this study was to investigate the possibility of transference to Escherichia coli of ??-lactam resistance genes found in bacteria isolated from ready-to-eat (RTE) Portuguese traditional food. From previous screenings, 128 ??-lactam resistant isolates (from different types of cheese and of delicatessen meats), largely from the Enterobacteriaceae family were selected and 31.3% of them proved to transfer resistance determinants in transconjugation assays. Multiplex PCR in donor and transconjugant isolates did not detect bla _CTX, bla _SHV and bla _OXY, but bla _TEM was present in 85% of them, while two new TEMs (TEM-179 and TEM-180) were identified in two isolates. The sequencing of these amplicons showed identity between donor and transconjugant genes indicating in vitro plasmid DNA transfer. These results suggest that if there is an exchange of genes in natural conditions, the consumption of RTE foods, particularly with high levels of Enterobacteriaceae, can contribute to the spread of antibiotic resistance.     

The use of data on the composition and drug resistance of the causative agents of suppuration in a retrospective analysis of the epidemiological situation in a hospital

The analysis of bacterial 16,530 strains, dynamically isolated from 6,157 patients with purulent septic processes (PSP) in surgical, traumatological, burn, toxicological and resuscitation departments, was made. The computer processing of data on the spread of the causative agents of PSP, depending on their taxonomic classification and drug resistance spectra, was carried out, which made in possible to obtain information on the outbreaks of hospital infections. Correlation of the number of PSP cases and the spread of hospital resistovars was analyzed. The data on the composition and drug resistance of pyogenic microorganisms could be used in the retrospective analysis of the epidemiological situation in a hospital. 3-year observations revealed the tendency to a decrease in the spread of the hospital variants of the causative agents of PSP, multiresistant to antibacterial preparations, which was indicative of the effectiveness of the antiepidemic measures carried out during this period.     

慢性肾盂肾炎L型细菌感染及耐药分析

目的了解L型细菌在慢性肾盂肾炎的感染及耐药状况。方法对71例患者清洁中段尿做普通细菌培养(B型)、L型细菌培养(L型)及耐药分析。结果细菌阳性率为77.5%,其中单独L型阳性率为49.3%、B型与L型混合感染为15.5%,而B型阳性率仅为12.7%。主要是大肠埃希菌,其次是葡萄球菌;青霉素及头孢噻肟均有较高的耐药率(88.9%及73.6%)。结论L型细菌在慢性肾盂肾炎感染中占主导,β-内酰胺类药物有较高的耐药性,临床治疗应据药敏结果合理选择及时调整抗生素。     

Nonenteric escherichiosis and the problem of human reproductive health

The contribution of nonenteric Escherichia infections (NEI) to the formation of male and female infertility is analyzed. The negative influence of NEI, and particularly pyelonephritis, on the course of pregnancy, parturition and the postnatal period is shown. The role of E. coli in the development of life-threatening meningoencephalitides, pneumonia, sepsis in newborn infants is emphasized, NEI risk factors are systematized with due regard to concrete stages in the pathogenesis of this pathology. Phenotypic differences between the causative agents of NEI and nonpathogenic and diarrhea-inducing E. coli are characterized.     

Effects of a specific nutrient combination on ESBL resistance

Background and aimExtended-spectrum beta-lactamases are the main cause of resistance in Enterobacteriaceae to beta lactam antibiotics. The aim of this study was to evaluate the antimicrobial effect of EpiQuercican supplement, combined with different antimicrobial agents, on ESBL-producing isolates and determine the underlying molecular mechanism of resistance in these isolates.Materials and methodsEleven ESBL producing Enterobacteriaceae isolates were collected from Saudi Arabia hospitals between 2016 and 2017 and disk diffusion test was performed in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines to determine the susceptibility of the isolates to 5 different antibiotics in the presence of EpiQuercican supplement. Polymerase chain reaction was performed for detection of ESBL genes, and efflux pump inhibitor was used to study the mechanism of resistance in these isolates.ResultsThe best synergistic effect was obtained when the supplement was combined with carbapenems followed by 4th generation cephalosporins. Either no effect or antagonistic effect was seen with most of the isolates when the supplement was added to the 3rd generation of cephalosporins. Among the tested genes responsible for ESBL production in this study, our results indicated the predominance of TEM genes (73%) followed by CTX-M genes (9%). As for the mechanism of resistance in ESBL isolates, 4 isolates showed to use efflux pumps as their main mechanism of resistance.ConclusionThe EpiQuercican supplement showed some promising results, yet its antibacterial mechanism of action needs to be elucidated further.     

Expansion of the host range of coliphage P1 and gene transfer from enteric bacteria to other gram-negative bacteria.

The bacterial host range of coliphage P1 was extented by using the heat-inducible phage P1clr100KM. A gene for kanamycin resistance was transferred from Escherichia coli to members of the family Enterobacteriaceae and some other genera of gram-negative bacteria. P1 phage was produced by thermal induction from the lysogens of all these kanamycin-resistant bacteria except some strains.     

Expansion of the host range of coliphage P1 and gene transfer from enteric bacteria to other gram-negative bacteria.

The bacterial host range of coliphage P1 was extented by using the heat-inducible phage P1clr100KM. A gene for kanamycin resistance was transferred from Escherichia coli to members of the family Enterobacteriaceae and some other genera of gram-negative bacteria. P1 phage was produced by thermal induction from the lysogens of all these kanamycin-resistant bacteria except some strains.     

Incidence of antimicrobial resistance among Enterobacteriaceae isolated in Riyadh

The antimicrobial resistance of 1,018 isolates of Enterobacteriaceae isolated from fecal specimens of the urban population of Riyadh, Saudi Arabia, was studied. Resistance to 1 or more of 10 antimicrobial agents was encountered in 50.2% of the isolates. Of the isolates tested,Escherichia coli (0.8%) andKlebsiella species (1.6%) were found resistant to seven antimicrobial agents simultaneously: ampicillin, chloramphenicol, kanamycin, colistin, streptomycin, tetracycline, and carbenicillin. Resistance to nalidixic acid was encountered in only 0.68% of theE. coli isolates. No isolate was found to be resistant to gentamicin. Eighty-six of the resistant strains were tested for their ability to transfer their resistance. Forty percent were able to do so withE. coli K-12.