Occurrence of Clostridium difficile infections due to PCR ribotype 027 in Bucharest, Romania.

INTRODUCTION: Little is known about prevailing ribotypes of Clostridium difficile infection in Romania where CDI is not a mandatory notifiable disease. METHODOLOGY: We studied 64 non-duplicate C. difficile isolates from patients hospitalised at the National Institute of Infectious Diseases, Bucharest, Romania between March 2011 and March 2012. RESULTS: Sixty-three of the 64 C. difficile isolates produced toxins A and B whereas 44 (69%) isolates produced a binary toxin. Ribotype 027 accounted for 43 (68%) of the 63 toxigenic strains. The remaining 20 isolates belonged to ribotypes 018 (n = 9), 012 (n = 3), and, with one isolate each, 014, 031, 081, 416, 433, 500, 507 and PR03035 (new ribotype). Information on hospital mortality was available for 62 of the 64 patients; among these 62 cases, 4 (6.4%) ended fatal. Recurrence was documented for 11 (18.3%) of the 60 patients for whom this information was available. Multilocus variable-number tandem repeat analysis of the 43 isolates of ribotype 027 yielded a unique cluster for the Romanian isolates when compared to Austrian or Italian isolates. CONCLUSION: Our findings sustain the hypothesis of a recent emerged outbreak of C. difficile PCR ribotype 027 infections in the area of Bucharest.

[Antibiotic resistance of Gram-positive cocci isolated in 2008]. / Rezistenta la antibiotice a cocilor Gram pozitivi izolati în 2008.

OBJECTIVE: Antibiotic resistance evaluation of Gram-positive cocci isolated in 2008. MATERIAL AND METHODS: Antibiotic susceptibility testing was performed for 1044 strains: 610 Staphylococcus aureus (352 from patients, 258 from carriers), 203 Streptococcus pneumoniae (53 from patients, 150 from carriers), 144 Enterococcus faecalis. 57 Enterococcus faecium and 30 Streptococcus spp. using automatic systems Vitek 2 Compact. MicroScan, disc diffusion method and Etest according to 2008 CLSI. A number of 497 Streptococcus pyogenes strains were tested for eritromycin resistance. RESULTS: There were 33.2% MRSA for strains isolated from patients and 30.0% from carriers. From MRSA strains. 35.5% were resistant to gentamicin. 33.6% to ciprofloxacin, 74.3% to erythromycin and 30.5% to rifampin. There were no S. aureus strain resistant to vancomycin and linezolid. S. aureus strains isolated from wounds were more resistant to erythromycin (43.9%) than the strains isolated from systemic infections (12.1%). From 11 S. pneumoniae strains isolated from meningitis, 4 were resistant to penicillin. Neither S. pneumoniae strain isolated from other infections, nor those from carriers had MIC to penicillin more than 4 microg/ml. S. pneumoniae strains isolated from carriers were more resistant to erythromycin. clindamycin and tetracycline than the strains isolated from patients (66.7%, 54.1%, 54.2% vs. 27.4%, 22.6%, 33.9%). E. faecium was 95.9% resistant to penicillin, 90.2% to ampicillin, 64.7% to gentamicin, 72.0% to streptomycin and 78.4% to ciprofloxacin. F. faecalis was less resistant than E. faecium at most of the antibiotics: 32.4% to gentamicin, 59.6% to streptomycin, 28.5% to ciprofloxacin. Viridans group Streptococci, all isolated from blood culture were 92% susceptible to penicillin and ampicillin. To erythromycin, 12% of viridians group Streptococci were resistant. S. pyogenes resistance to eritromycin was 5.8%. CONCLUSIONS: S. aureus strains showed a relatively high level of resistance to oxacillin (33.2%) and resistance in the same time to several antibiotics. S. pneumoniae can not be considered resistant to penicillin administrated parenteral, with exception of the strains isolated from meningitis. E. faecium had a higher resistance rate than E. faecalis.

Cefpirome susceptibility in staphylococci isolates.

UNLABELLED: Cefpirome is a fourth-generation cephalosporin with an expanded spectrum against both Gram-negative and Gram-positive bacteria. The objective of this study was to evaluate the in vitro activity of cefpirome against staphylococci, clinical isolates. For comparison oxacillin was also tested. MATERIAL AND METHODS: A total 434 isolates (coagulase-positive staphylococci, n = 268 and coagulase-negative staphylococci, n = 166) were tested. Susceptibility testing was performed using the Mueller-Hinton agar dilution method. RESULTS: Cefpirome inhibited the majority of strains at 0.5-8 mg/l. Cefpirome had excellent activity against coagulase-negative staphylococci with 91.6% susceptibility. Except the coagulase-positive staphylococci, of the 268 isolates, 81.3% were cefpirome sensitive. Concerning oxacillin, 35.1% of coagulase-positive staphylococci isolates were resistant, comparative with 26.5% of the coagulase-negative staphylococci. A cross-resistance analysis showed the association of resistance between cefpirome and oxacillin. CONCLUSION: Against staphylococci, cefpirome had the best activity when compared with the oxacillin.

Susceptibility of Klebsiella spp. to cefpirome and cefepime.

Cefpirome and cefepime possess a greater antibacterial spectrum in vitro than third-generation cephalosporins because they are active against Enterobacteriaceae, which produce beta-lactamases, which may inactivate third-generation cephalosporins. The aim of this study was to quantitatively compare the in vitro activity of cefpirome and cefepime against Klebsiella spp. isolates. We have studied 342 Klebsiella spp. clinical isolates, from some hospitals in Eastern Romania. Minimum inhibitory concentrations (MICs) were determined by the dilution method in Mueller-Hinton agar. The mean MIC of sensitive population by cefpirome and cefepime was 1 mg/l, eight fold lower than breakpoint for susceptibility. The cefpirome and cefepime MICs remained below the proposed breakpoints for sensitivity of 8 mg/l for more 60% of strains. Mean "S" (mean MIC of the fully sensitive strains) is a very good indicator of the drug activity. Cefpirome and cefepime are active fourth-generation cephalosporins against clinical isolates of Klebsiella spp.

[Susceptibility to norfloxacin of some bacterial strains causing urinary infections]. / Sensibilitatea la norfloxacin a unor tulpini bacteriene implicate in infectii urinare.

The purpose of this study was to evaluate the in vitro activity of norfloxacin in comparison with ofloxacin, pefloxacin and ciprofloxacin against 662 strains. The studied strains were obtained from urine, during 2003 period, in Eastern region of Romania. The minimum inhibitory concentrations (MICs) were determined on Mueller-Hinton agar by the dilution technique, with an inoculum of 10(5) CFU/spot. Among tested quinolones, norfloxacin has the better activity against tested strains. The fluoroquinolone compounds were very potent against Escherichia coil strains. Our data shown the spread of quinolone resistance in our area and demonstrated the necessity of adequate antibiotic use in the hospital and community.

[In vitro antibacterial activity and beta-lactamase stability of meropenem]. / Activitatea antibacteriana in vitro si stabilitatea la beta-lactamaze a meropenemului.

The comparative activity of meropenem with that of imipenem, cefotaxime, ceftriaxone and ceftazidime against 856 gram-negative bacilli was studied studied by an agar dilution method. Meropenem and imipenem were high active against tested strains. Resistance to third generation cephalosporins was high for most microorganisms tested. For rapid detection of metallo-beta-lactamase (MBL)-producing gram-negative bacilli a simple disk diffusion test was used. EDTA, FeCl2 and CuCl2 were evaluated as IMP-1 inhibitors. The method is helpful for screening of IMP-1 producers in daily clinical activity.

[Activity of fourth generation cephalosporins against clinical isolates of Enterobacteriaceae]. / Activitatea cefalosporinelor de generatia a patra asupra unor izolate clinice de enterobacterii.

Cefpirome and cefepime are a novel group of cephalosporins which contain a positively charged quaternary ammonium at carbon 3 of the dihidrothiazone ring. The antimicrobial agents cefpirome, cefepime, cefotaxime, ceftriaxone, ceftazidime, cefoperazone and imipenem were tested against clinical isolates of Escherichia coli (n = 302) and Klebsiella spp. (n = 62) obtained during september-december 2002 from patients of Galati Emergency Hospital. The fourth generation cephalosporins cefpirome and cefepime have similar in vitro activities to the third generation cephalosporins. E. coli showed the comparable resistance rates for all cephalosporins. Against Klebsiella spp. strains cefpirome was less active (35.5% resistance) than cefepime (25.8% resistance). As expected, imipenem had excellent activity (100% susceptibility).

A study for the improvement of the cytological urine examination performances in upper tract infection diagnosis.

Diagnosis of the location of upper and lower urinary tract infection (UTI) is necessary in defining the therapeutic conduct that has a different period and intensity according to the infection location and in prognosis. Many studies show the lack of clinical criteria peculiarity in revealing the different location of UTI. As a result, the correct location of the level in which UTI develops is the necessity of paraclinical investigations. Urinary sample examination, in which urinary sediment microscopy is essential, is a reliable technique in fast detection and localization of UTI. Finding, in pyuria context, the classic significant bacteriuria (> or = 10(5) CFU/ml) or lower value bacteriuria (< or = 10(4) CFU/ml) confirms the UTI diagnosis. The upper tract infection prognosis increases when leukocyte cylinders, characteristic for pyelonephritis, appear together with intact or degraded leukocytes, single or grouped. We settled an algorithm to examine the urine samples in order to: Concentrate and preserve the structural integrity of leukocytes and cylinders, examining the conventional urinary sediment Precisely identify and differentiate these elements by vital coloration (leukocyte peroxidase coloration and Sternheimer - Malbin coloration) to establish more accurate the UTI level. The vital coloration for leukocyte peroxidase has cytological specificity, confirming the pyuria and the cylinders that contain leukocytes (leukocytary, granular, mixed) and obviously ameliorates the reliability and reproducibility of the urinary sediment cytological exam.

In vitro susceptibility of staphylococci to linezolid and other antimicrobial agents.

Linezolid is a member of the new class of antibacterial agents called oxazolidinones that are active against Gram positive organisms and exert their action by protein synthesis inhibition. In this study we investigated the in vitro activity of linezolid versus the other agent against clinical strains of staphylococci: Staphylococcus aureus (n = 82) and S. epidermidis (n = 32) collected in 2002 from hospitalized patients and healthy individuals, isolated from different biological samples. Agar dilution minimum inhibitory concentrations (MICs) were determined by using Mueller-Hinton agar according to the guidelines established by the National Committee for Clinical Laboratory Standards. Linezolid demonstrated excellent in vitro activity against all isolates tested, with MICs values in the range of susceptibility (< or = 8 microg/ml). No associated resistance between linezolid and other agents tested was observed. The resistance among Gram positive bacteria continues to spread and for many patients infected with these resistant organisms antimicrobial therapy is ineffective and linezolid may be a new alternative treatment.

Resistance pattern of extended-spectrum beta-lactamase producing Enterobacteriaceae isolates.

Gram-negative pathogens harboring extended-spectrum beta-lactamases (ESBL) are becoming an increasing therapeutic problem in many wards. The aim of our work was to study ESBL production by Enterobacteriaceae strains from Eastern Romania and their antimicrobial resistance. We selected 54 clinical isolates among 1068 enterobacteria according to their susceptibility spectrum (National Committee for Clinical Laboratory Standards, 1999). Antimicrobial susceptibility tests were performed using the Rapid ATB E gallery of mini API system (BioMérieux) and by a macrodilution method in Mueller-Hinton agar following standard procedure of the National Committee for Clinical Laboratory Standards (NCCLS). ESBL production was established by using both double disk synergy test (DDT) and Expert computer program of mini API. The isoelectric point (pI) was determined by isoelectric focusing in polyacrylamide gel and revealed by nitrocefin. As references we used beta-lactamases with known pI. The Expert computer program of mini API confirms the positive DDT test for all selected strains. Almost all strains displayed resistance to ampicillin, ampicillin/sulbactam or third generation cephalosporins and aztreonam. By IEF we identified 51 strains which have a unique enzyme. IEF pattern showed presence of two enzymes in three Escherichia coli strains. According to our results, the ESBL TEM-type are the most common for the studied isolates. The production of extended-spectrum beta-lactamases and the presence of the multiresistant of antimicrobial agents reflect, probably, the over use of third generation cephalosporins in Eastern Romania.