[Antibiofilm activity of agents for disinfection of skin, mucosa, and wound on microorganisms isolated from patients with catheter-related infections]. / Vplyv prípravkov urcených na dezinfekciu koze, slizníc a rán na zivotaschopnost biofilmovej formy rastu mikroorganizmov izolovaných od pacientov s katétrovými infekciami.

AIM OF THE STUDY: To evaluate the activity of four disinfectious agents used for skin, mucosa and wound disinfection (chlorhexidine digluconate, povidone-iodine, octenidine hydrochloride, super oxygenated water) on the biofilm of Staphylococcus aureus, Escherichia coli and Candida sp. strains, isolated from patients with catheter-related infections. MATERIAL AND METHODS: The tested agents were applied on 24-hours biofilm in the microtiter plate wells. After 20-minutes exposition, the wells were washed, and the microbial vitality was tested by regrowth method after 24-hours cultivation in fresh culture medium. Biofilm formation was confirmed in a parallel microtiter plate; the quantity of produced biofilm was measured after crystal violet staining spectrophotometrically at 570 nm. RESULTS: All four tested disinfectious agents inactivated the biofilm of all S. aureus, E. coli, C. albicans, C. krusei and C. glabrata strains, without respect to the intensity of biofilm production. Three strains of C. tropicalis with intensive biofilm production partially preserved their vitality after exposition to chlorhexidine and povidone-iodine, and 2 strains to octenidine. Super oxygenated water had no effect on yeasts associated with massive biofilm of one C. tropicalis strain, and only partially decreased the vitality of additional two strains. CONCLUSIONS: The tested disinfectious agents proved in-vitro antibiofilm activity on all microbial strains from catheter-related infections, with exception of three C. tropicalis strains with intensive biofilm production. Octenidine was found to be the most active agent. The results enable to assume, that the tested disinfectious agents, when applied to patients, will inactivate not only the individual microorganisms not protected by biofilm, but also the biofilm on the catheter surfaces approachable by local application. However, C. tropicalis strains producing massive biofilm, protecting them partially from effects of disinfectious agents tested in the present study, still remain a challenge.

[Clinical and microbiological characteristics of severe infections caused by group A streptococci]. / Klinická a mikrobiologická charakteristika závazných infekcii sposobených streptokokmi skupiny A.

AIM OF THE STUDY: Analysis of data on the occurrence of severe infections caused by group A streptococci, emm typing of the isolated strains, and survey of resistance to the selected antibiotics. MATERIAL AND METHODS: In 2012 and 2013, 43 S. pyogenes strains were isolated from severe infections. The isolates were most often recovered from wounds and abscesses (36 patients), followed by blood culture (5 patients), sputum (1 patient), and autopsy samples (1 patient). Antimicrobial susceptibility to selected antibiotics ( penicillin, erythromycin, clindamycin, spiramycin, and tetracycline) was tested by the disk-diffusion method and the minimal inhibitory concentrations (MICs) were determined. RESULTS: In 2012 and 2013, an increase in severe streptococcal infections was observed, with 27 and 16 cases reported, respectively. Resistance to macrolides was detected in 18.5% and 12.5% of isolates, respectively, and resistance to tetracycline in 25.9% and 20% of isolates, respectively. The isolated S. pyogenes strains were most often assigned to emm type 1. Risk factors for streptococcal infection were analyzed, with injury being most often identified as a risk factor- in seven and two patients, respectively. The patients were most frequently treated by beta-lactam antibiotics (penicillin and ampicillin). In 2012, two cases were fatal. CONCLUSION: This study reports cases of invasive group A streptococcal (GAS) infection as seen in clinical practice. An increased occurrence of S. pyogenes was observed in the hospital, with the isolates exhibiting elevated resistance to erythromycin and tetracycline. It is necessary to monitor the trends of antimicrobial resistance and the distribution of emm types among group A streptococcal isolates. Cooperation of the laboratory and clinical professionals in the prevention and therapy of streptococcal infections, invasive in particular, is crucial for risk reduction.

Microbiological and therapeutical aspects of pneumococcal diseases in the Slovak Republic.

Since 1983, multiresistant pneumococcal strains, mostly 14, 23F, 19A serotypes have been reported in Slovakia. A 15-year cooperation of specialists from various fields and the representatives of different institutions revealed that the pneumococcal infection problem in the Slovak Republic remains an important healthcare task. In the prospective multicentric microbiological and clinical analysis of otitis media acuta in children under 5 years, pneumococci were isolated in 45.9%, where 50.8% of strains were intermediate and fully resistant to penicillin and 47.5% resistant to macrolid antibiotics. Invasive pneumococcal infections, mostly meningitis and bacteremias, were observed in two studies. Penicillin resistance was higher in children under 5 years (52.8%), in comparison with other age groups. The dominant serotypes of childhood were 14, 19A and 6A, while in the age group above 65 there was a broad spectrum of serotypes confirmed. Serotype 14 is the most frequent serotype in physiologically sterile liquids and otitis media liquor in the Slovak Republic (Tab. 3, Fig. 5, Ref. 34).

Two cases of severe invasive infections in children caused by Streptococcus pneumoniae serotype 14--case report.

Two cases are presented of severe pneumococcal infections in infants caused by serotype 14 Streptococcus pneumoniae. The first case--meningitis--caused by S. pneumoniae (pneumococcus) with low-level penicillin susceptibility has developed from acute otitis media and resulted in fatal outcome. The second one--an immunocompromised child presenting recurrent otitis and chronic mastoiditis--developed into pneumococcal pneumonia. Both cases demonstrate the extreme importance of a relevant initial treatment of localized pneumococcal infections, preventing the development of generalized infection. Amoxicillin (an oral treatment option in both upper and lower respiratory tract infections caused also by Pneumococcus strains with low-level penicillin susceptibility due to its beneficial pharmacokinetics and pharmacodynamics) was not used in either case.

Activity of telithromycin and seven other agents against 1034 pediatric Streptococcus pneumoniae isolates from ten central and eastern European centers.

OBJECTIVE: To test the activity of telithromycin against 1034 Streptococcus pneumoniae isolates from pediatric patients in ten centers from ten central and eastern European countries during 2000-2001, and to compare it with the activities of erythromycin A, azithromycin, clarithromycin, clindamycin, and quinupristin-dalfopristin. METHODS: The minimum inhibitory concentrations (MICs) of telithromycin, erythromycin A, azithromycin, clarithromycin, clindamycin, levofloxacin, quinupristin-dalfopristin and penicillin G were tested by the agar dilution method with incubation in air, and mechanisms of resistance to macrolides and quinolones were investigated. RESULTS: Strains were isolated from sputum, tracheal aspirates, ear, eye, blood, and cerebrospinal fluid. Among S. pneumoniae strains tested, 36% had raised penicillin G MICs (>/= 0.12 mg/L). Susceptibilities were as follows: telithromycin, quinupristin-dalfopristin and levofloxacin, >/= 99%; clindamycin, 83%; and erythromycin A, azithromycin and clarithromycin, 78%. Of 230 (22.3%) erythromycin A-resistant S. pneumoniae strains, 176 (79.6%) had erm(B), 38 (16.1%) had mef(A), and 10 (4.3%) had mutations in 23S ribosomal RNA or in ribosomal protein L4. The rates of drug-resistant S. pneumoniae are high in all centers except Kaunas, Riga, and Prague. CONCLUSION: Telithromycin had low MICs against all strains, irrespective of macrolide, azalide or clindamycin resistance. Ribosomal methylation was the most prevalent resistance mechanism among all resistant strains, except in Sofia, where the prevalence of the efflux mechanism was higher.

Activity of telithromycin compared with seven other agents against 1039 Streptococcus pyogenes pediatric isolates from ten centers in central and eastern Europe.

In total, 1039 pediatric Streptococcus pyogenes isolates from Bulgaria, Croatia, the Czech Republic, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia and Slovenia were studied. All strains were susceptible to penicillin G, levofloxacin, and quinupristin-dalfopristin, 91-100% to telithromycin, and 82-100% to erythromycin, azithromycin, and clarithromycin, and 90-100% to clindamycin. Macrolide resistance occurred mainly in Slovakia (25%), the Czech Republic (17.3%), and Croatia (15.8%). Overall, 9.7% of S. pyogenes isolates were erythromycin resistant due to erm(B)- or erm(A)-encoded methylases (72.3%) or to a mef(A)-encoded efflux pump (25.7%). One strain had alterations of both 23S rRNA (A2058G Escherichia coli numbering) and ribosomal protein L22 (G95D).

In vitro susceptibility of 90 penicillin-susceptible and -resistant pneumococci to penicillin G, amoxicillin, amoxicillin/clavulanate, cefaclor, cefuroxime, cefpodoxime, cefixime and imipenem.

In vitro susceptibility of eight antibiotics was compared using three groups of pneumococci and agar dilution method comprising 30 penicillin-susceptible, 30 intermediately penicillin-resistant, and 30 highly penicillin-resistant pneumococci. Decreased sensitivity to all beta-lactam agents of intermediately penicillin-resistant and highly penicillin-resistant pneumococci is shown. MIC50 and MIC90 was lower with amoxicillin with and without clavulanate by one dilution than with penicillin. Cephalosporin MIC90s were all significantly higher for intermediately resistant and fully resistant strains. Only imipenem was more active than penicillin with MIC90 of susceptible pneumococci 0.015 mg/L, intermediately resistant pneumococci 0.25 mg/L, resistant pneumococci 1 mg/L.

The incidence of penicillin-resistant pneumococci in the Slovak Republic. Pneumococcus Study Group.

The prevalence of penicillin-resistant Streptococcus pneumoniae and multiresistant strains isolated in Europe from the early 1970s has continued to rise. Twenty-four microbiology laboratories in the Slovak Republic analyzed 4,018 S. pneumoniae strains isolated from September 1, 1993, to December 31, 1993. The overall resistance rate to penicillin was 3.4% in strains isolated from outpatients and 8.5% from inpatients with considerable variation between regions. The highest regional resistance rate to penicillin was 21% from outpatients in Levice, in the western Slovakia, and ranged between 13 and 52% in strains collected from hospitalized patients in 6 regions. Rates of penicillin-resistant pneumococci were significantly higher (p < or = 0.01) in children aged < or = 3 years. Two thirds of penicillin-resistant strains had intermediate levels of resistance (MICs 0.1-1 microgram/ml) and one third was resistant (MICs 2-8 micrograms/ml). Resistance to multiple classes of agents was found in 75.9% of penicillin-resistant strains. These data support continued surveillance of antimicrobial resistance in pneumococcal infections. Standardization of susceptibility testing methods and monitoring of clinical outcomes is of critical importance to this complex problem.

Bacteremia due to Enterobacter spp. in cancer patients--analysis of 51 episodes.

Fifty one episodes of bacteremia due to Enterobacter spp. appearing within 7 years among 12 301 admissions in a single cancer institution were studied for risk factors, clinical presentation and outcome. Fifteen episodes were due to Enterobacter aerogenes, 23 due to E. cloacae and 13 due to E. agglomerans. The proportion of bacteremia due to Enterobacter spp. among Gram-negative bacteremias was 10.1% and infection associated mortality was 13.8%. The incidence in 1989-1995 varied from 3.7 to 8.7% and was relatively stable. Most common risk factors were: solid tumors as underlying disease, central venous catheter insertion, prior surgery and prior chemotherapy within 48 h. Neutropenia and urinary catheters were not at high risk in either one of the patients subgroups. Comparing two subgroups of 51 bacteremias, monomicrobial and polymicrobial (when Enterobacter spp. was isolated from blood culture with other microorganism), previous chemotherapy, vascular catheter insertion and prior endoscopy were more frequently associated with polymicrobial Enterobacter spp. bacteremia. There was also differences in infection associated mortality: bacteremias due to Enterobacter spp. only had significantly lower mortality in comparison to polymicrobial Enterobacter spp. bacteremias (3.3 vs. 29.3%; P<0.02). Susceptibility of Enterobacter spp. strains isolated from 51 episodes was stable and showed only two episodes due to quinolone-resistant strains, both in 1992 despite of the use of ofloxacin in prophylaxis of neutropenic patients since 1990 in our institute. Ninety-two to 94% of all strains were susceptible to aminoglycosides, 96-98% to ofloxacin and ciprofloxacin, respectively and 94.9% to meropenem but only 75.5% to ceftazidime.

In vitro susceptibility of pneumococci to trovafloxacin, penicillin G, and other antimicrobial agents in the Czech Republic and Slovakia.

The in vitro activity of the new naphthyridone trovafloxacin (CP 99,219) was compared with those of penicillin G and six other agents (cefpodoxime, erythromycin, azithromycin, clindamycin, ciprofloxacin, and sparfloxacin) against 316 penicillin-susceptible and -resistant pneumococci isolated in the former Czechoslovakia. Trovafloxacin was very active against strains of Streptococcus pneumoniae (MIC50 and MIC90 0.25 microgram/ml). Ciprofloxacin was less active (MIC50 1.0 microgram/ml, MIC90 2.0 micrograms/ml), and MICs of sparfloxacin were between those of trovafloxacin and ciprofloxacin (MIC50 and MIC90 both 0.5 microgram/ml). MICs of cefpodoxime, erythromycin, azithromycin, and clindamycin were higher for strains intermediately resistant or resistant to penicillin than for penicillin-susceptible strains.