Stenotrophomonas maltophilia Pseudo-outbreak at a University Hospital Bronchoscopy Unit in Turkey.

OBJECTIVE: Stenotrophomonas maltophilia is an opportunistic pathogen found predominantly in the environment and hospital setting. Invasive procedures and treatment methods, instruments used for diagnosis and irrational antibiotic use play major roles in the spread of this pathogen. The study aimed to evaluate consecutive S maltophilia isolation from bronchoalveolar lavage samples during bronchoscopy procedure during a week. METHODS: Four patients consecutively had S maltophilia isolated during bronchoscopy between September 8 and 15, 2012. The identification of the isolates and their antibiotic susceptibility were studied by automated Vitek version 2.0 (Biomerieux, France) system. The clonal relationship between the isolates was studied by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR). RESULTS: Four consecutive S maltophilia isolates had identical band patterns and showed clonal relatedness. CONCLUSION: Bronchoscopy is a common invasive procedure that is utilized in chest diseases departments and intensive care units (ICUs). Contamination may take place due to inappropriate use and cause spread of infectious pathogens. In the current study, we detected consecutive S maltophilia strains with identical band patterns isolated within a week. After appropriate disinfection and cleaning procedures, no further isolation was detected.

In vitro effect of moxifloxacin and rifampicin on biofilm formation by clinical MRSA isolates.

OBJECTIVE: In this study, it was aimed to investigate in vitro activity of moxifloxacin and rifampicin on biofilm formation by clinical MRSA isolates. BACKGROUND: Methicillin resistant Staphylococcus aureus (MRSA) strains could be the causative agent in chronical and medical device associated infections by biofilm formation. METHODS: Moxifloxacin and rifampicin MIC values of 98 MRSA clinical isolates were determined by microdilution method. Biofilm formation of all isolates was determined in 96-well microplates by using spectrophotometric method. Effects of MIC and sub-inhibitory concentrations (1/2 and 1/4 MIC) of antibiotics on biofilm formation were examined in 46 strong biofilm producer strains. RESULTS: Biofilm production decreased in 37 and 44 isolates at all studied concentrations of moxifloxacin and rifampicin, respectively. Biofilm production increased in six isolates with moxifloxacin and in two isolates with rifampicin. CONCLUSION: Biofilm inhibitory effect of rifampicin was found to be stronger than moxifloxacin in the examined strains. The studied antimicrobials also induced biofilm formation in some strains. Results of this study may help to evaluate the effects of these antibiotics on biofilm formation of clinical MRSA strains and to control the antibiotic resistance in clinical settings (Tab. 2, Ref. 25).

Stenotrophomonas maltophilia pseudo-outbreak at a University Hospital Bronchoscopy unit in Turkey / Pseudo-brote de Stenotrophomonas maltophilia en una unidad de Broncoscopia del Hospital Universitario en Turquía

OBJECTIVE: Stenotrophomonas maltophilia is an opportunistic pathogen found predominantly in the enviroment and hospital setting. Invasive procedures and treatment methods, instruments used for diagnosis and irrational antibiotic use play major roles in the spread of this pathogen. The study aimed to evaluate consecutive S maltophilia isolation from bronchoalveolar lavage samples during bronchoscopy procedure during a week. METHODS: Four patients consecutively had S maltophilia isolated during bronchoscopy between September 8 and 15, 2012. The identification of the isolates and their antibiotic susceptibility were studied by automated Vitek version 2.0 (Biomerieux, France) system. The clonal relationship between the isolates was studied by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR). RESULTS: Four consecutive S maltophilia isolates had identical band patterns and showed clonal relatedness. CONCLUSION: Bronchoscopy is a common invasive procedure that is utilized in chest diseases departments and intensive care units (ICUs). Contamination may take place due to inappropiate use and cause spread of infectious pathogens. In the current study, we detected consecutive S maltophilia strains with identical band patterns isolated within a week. After appropiate disinfection and cleaning procedures, no further isolation was detected.

OBJETIVO: Stenotrophomonas maltophilia es un patógeno oportunista que se encuentra predominantemente en el medio ambiente y entorno de los hospitales. Los procedimientos invasivos y los métodos de tratamiento, los instrumentos utilizados para el diagnóstico y tratamiento, así como el uso irracional de antibióticos, desempeñan un importante papel en la propagación de este patógeno. Este estudio persigue evaluar el aislamiento consecutivo de S maltophilia de las muestras de lavado broncoalveolar durante el procedimiento broncoscópico en el período de una semana. MÉTODOS: A cuatro pacientes se les aisló S maltophilia consecutivamente en broncoscopias realizadas entre el 8 y el 15 de septiembre de 2012. La identificación de los aislamientos y su sensibilidad a los antibióticos fueron estudiados por el sistema automatizado Vitek 2 (Biomerieux, Francia). La relación clonal entre los aislamientos fue estudiada mediante consenso intergénico repetitivo enterobacteriano (ERIC) en conjunción con la reacción en cadena de la polimerasa (PCR). RESULTADOS: Cuatro aislados consecutivos de S maltophilia tenían patrones de banda idénticos y exhibían conexidad clonal. CONCLUSIÓN: La broncoscopia es un procedimiento invasivo común que se aplica en los departamentos de enfermedades torácicas, y las unidades de cuidados intensivos (UCI). La contaminación puede ocurrir debido a usos inapropiados y a la propagación de agentes patógenos infecciosos. En el presente estudio, hemos detectado cepas de S maltophilia consecutivas con idénticos patrones de banda aislados en una semana. Después de los procedimientos de limpieza y desinfección adecuada, no se detectó ningún otro aislamiento.

Molecular epidemiology of PER-1 extended spectrum beta-lactamase among gram-negative bacteria isolated at a tertiary care hospital.

The bla(PER-1) presence was sought by PCR in 289 ceftazidime resistant Gram-negative bacteria isolated at Dokuz Eylul University Hospital (Turkey) between 1998 and 2003. PER-1 production rates were 32.3, 33.9, 14.9 and 37.9% in the 1998-2000 period, 2001, 2002 and 2003, respectively. bla(PER-1) was detected in 46.2 and 35.9% of ceftazidime-resistant Pseudomonas aeruginosa and Acinetobacter baumannii isolates, respectively. ERIC-PCR results revealed that dissemination of two endemic clones for both P. aeruginosa (X and Y) and A. baumannii (A and B) was responsible for the high prevalence. Results of the conjugation tests and plasmid curing experiments suggested that bla(PER-1) was located on the chromosome in the representative strains. It was also shown for the first time that bla(PER-1) in a clinical isolate was associated with class-1 integron which could facilitate dissemination of bla(PER-1) among bacteria.

PER-1 production in a urinary isolate of Providencia rettgeri.

A Providencia rettgeri strain resistant to extended-spectrum cephalosporins and intermediate to aztreonam was isolated from the urine of a patient hospitalized in the urology clinic of SSK Educational Hospital in Ankara. Clavulanic acid restored the activity of extended-spectrum cephalosporins, suggesting that the strain was harboring an extended-spectrum beta-lactamase. Since the PER-1 enzyme is widespread in Turkey, and had been already detected in a related species such as Proteus mirabilis, the Providencia strain was suspected of harboring a PER-1 enzyme, which was indeed detected by PCR. This is the first description in a P. rettgeri isolate of a PER-1 enzyme which is widespread among Acinetobacter baumanni and Pseudomonas aeruginosa strains in Turkey.

[Mutations of gyrA in ciprofloxacin resistant Escherichia coli strains]. / Siprofloksasine dirençli Escherichia coli suslarinda gyrA mutasyonlarinin incelenmesi.

In this study, the relationship between gyrA mutations and ciprofloxacin minimum inhibitory concentration (MIC) values was investigated in Escherichia coli strains. For this purpose, ciprofloxacin MIC values of 46 E. coli strains, isolated from out-patients and hospitalized patients, were determined by the agar dilution method. The "Quinolone Resistance Determining Region" (QRDR) of gyrA gene was amplified and restricted by Hinf-I enzyme. Ser-83 mutation was observed in all strains that have ciprofloxacin MIC values of 0.062 mg/L and higher. Afterwards, eight strains, that were found susceptible (MIC < 1 mg/L, n: 1), intermediate (MIC: 1-4 mg/L, n: 1) and high level resistant (MIC > 4 mg/L, n: 6) to ciprofloxacin, were chosen and mutations in QRDRs of these strains investigated by DNA sequence analysis. Ser 83 Leu mutation was found in all the chosen strains and Asp 87 Tyr or Asp 87 Asn mutations were also observed except the ciprofloxacin susceptible (MIC: 0.062 mg/L) one. In addition, base substitutions that don't lead to aminoacid changes were detected. The strain in which only Ser 83 Leu mutation was observed, showed high level nalidixic acid resistance (MIC > 256 mg/L). This fact was in favour of that, one mutation is enough to develop high level resistance to nalidixic acid. It was concluded that high level ciprofloxacin resistance requires at least two mutations in the QRDR of gyrA gene.