Nasal carriage of methicillin-resistant and methicillin-susceptible Staphylococcus aureus in nursing home residents in Bolu, Turkey.

BACKGROUND: This study aimed (a) to provide information on methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) Staphylococcus aureus colonization ratio in residents of nursing homes; (b) to determine the effect of hand-washing education given to nursing home residents and employees on nasal carriage of Staphylococcus aureus (NCSA) and (c) to obtain probable risk factors for MRSA colonization of residents in two nursing homes. METHODS: Seventy-nine volunteers (24 females and 55 males) from Bolu nursing homes were included in the study. Nasal samples were taken with sterile swabs from the anterior nares. Staphylococcus aureus strains were identified using classical methods and genotyping of methicillin resistant strains was done using Arbitrary Primed PCR (AP-PCR). Antibiotic susceptibilities were determined by disk diffusion methods according to NCCLS standards. After first nasal samples were taken, all employees and residents of nursing homes were educated about the methods of hand hygiene over two days. RESULTS: With hand-washing education, the decrease of NCSA rate (initially 43%; after education, 21%) was significant (p < 0.05) while decrease of MRSA carriage (initially 5%, after education 1%) was not (p > 0.05). MRSA carriage was significantly correlated with presence of skin lesions, prior hospitalization within the last six months, and antibiotics usage within the last six months. AP PCR results suggested that residents' carriage of MRSA was the result of the same source. CONCLUSION: MSSA and MRSA colonization rates were found to be 38% and 5% in nursing homes, respectively. These ratios can decrease with simple precautions like hand-washing after a short education period

Nasal carriage of methicillin-resistant and methicillin-susceptible Staphylococcus aureus in nursing home residents in Bolu, Turkey / Portación Nasal de Staphylococcus Aureus Resistentes a la Meticilina y Susceptible a la Meticilina en los Residentes del Hogar de Ancianos en Bolu, Turquía

BACKGROUND: This study aimed (a) to provide information on methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) Staphylococcus aureus colonization ratio in residents of nursing homes; (b) to determine the effect of hand-washing education given to nursing home residents and employees on nasal carriage of Staphylococcus aureus (NCSA) and (c) to obtain probable risk factors for MRSA colonization of residents in two nursing homes. METHODS: Seventy-nine volunteers (24 females and 55 males) from Bolu nursing homes were included in the study. Nasal samples were taken with sterile swabs from the anterior nares. Staphylococcus aureus strains were identified using classical methods and genotyping of methicillin resistant strains was done using Arbitrary Primed PCR (AP-PCR). Antibiotic susceptibilities were determined by disk diffusion methods according to NCCLS standards. After first nasal samples were taken, all employees and residents of nursing homes were educated about the methods of hand hygiene over two days. RESULTS: With hand-washing education, the decrease of NCSA rate (initially 43; after education, 21) was significant (p 0.05). MRSA carriage was significantly correlated with presence of skin lesions, prior hospitalization within the last six months, and antibiotics usage within the last six months. AP PCR results suggested that residents' carriage of MRSA was the result of the same source. CONCLUSION: MSSA and MRSA colonization rates were found to be 38and 5in nursing homes, respectively. These ratios can decrease with simple precautions like hand-washing after a short education period.

ANTECEDENTES: Este estudio tiene como propósito: (a) ofrecer información sobre la tasa de colonización Staphylococcus aureus resistentes a la meticilina (SARM) y el de Staphylococcus aureus susceptibles a la meticilina (SASM) de residentes en hogares de ancianos; (b) determinar el efecto de la educación del lavado de manos brindada a los residentes y empleados, sobre la portación nasal de Staphylococcus aureus (PNSA); y (c) obtener los factores de riesgo probables por la colonización de SARM en los residentes de dos hogares de ancianos. MÉTODOS: Setenta y nueve voluntarios (24 hembras y 55 varones) de los hogares de ancianos Bolu fueron incluidos en el estudio. Se tomaron muestras nasales con hisopos estériles, de 1/3 orificios nasales anteriores. Se identificaron cepas de Staphylococcus aureus usando métodos clásicos; y la genotipificación de las cepas resistentes a la meticilina se realizó por medio de la técnica de la reacción en cadena de la polimerasa con iniciadores arbitrarios (AP-PCR). Las susceptibilidades antibióticas se determinaron mediante métodos de difusión por disco de acuerdo con los estándares del NCCLS. Después que se tomaron las primeras muestras nasales, todos los empleados y los residentes de los hogares de ancianos recibieron instrucción sobre métodos de higiene de las manos durante dos días. RESULTADOS: Con la educación del lavado de manos, la disminución de la tasa de PNSA (inicialmente 43%; después del entrenamiento 21%) fue significativa (p < 0.05), mientras que la disminución de la tasa de portación de SARM (inicialmente 5%; después del entrenamiento 1%) no fue significativa (p > 0.05).

Exposure time to hepatitis B virus and associated risk factors among children in Edirne, Turkey.

Hepatitis B virus (HBV) infection is endemic in Turkey, but the main routes of transmission were not well established. This study aims to detect the exposure time to HBV and associated risk factors among children. In a sampling group of children aged 0-19 years living in Edirne, antiHBc, antiHBs and HBsAg were screened by the microELISA method. A questionnaire was also completed for each child. In 717 children that were included in the study, the total antiHBc seropositivity was 5.4% and was 1.8, 0.8, 1.7, 6.8, 11.8% in 0-1, 2-5, 6-10, 11-14, 15-19 years age groups respectively. The overall HBsAg seropositivity was 1.7%. The risk of HBV infection increased after the age of 10 years (OR 7.79, 95% CI 3.01-20.16). Collective circumcision was the only independent factor according to regression analysis. Children living in Edirne should be vaccinated against HBV before reaching 11 years of age.

Antimicrobial resistance patterns and serotype distribution among Salmonella enterica strains in Turkey, 2000-2002.

Since Turkey currently lacks a national reference center for Salmonella infections, the present study was conducted to document the distribution of serotypes and antimicrobial resistance patterns among Salmonella enterica isolates recovered from clinical samples in ten Turkish provinces over a 2-year period. Among the 620 Salmonella enterica isolates recovered between 1 July 2000 and 30 June 2002, strains belonging to the serotypes Enteritidis (47.7%), Typhimurium (34.7%), Paratyphi B (6.0%), Typhi (2.9%), Paratyphi A (0.2%) and serogroup C (8.5%) were found. Resistance to multiple antimicrobial agents was particularly high among Salmonella Typhimurium isolates (76.7%), and resistance or decreased susceptibility to ciprofloxacin (MIC> or =0.125 mg/l) was demonstrated in Salmonella Paratyphi B, Salmonella Typhimurium and Salmonella Enteritidis strains. All of the Salmonella Typhi isolates were susceptible to ciprofloxacin. The results indicate that decreased susceptibility to ciprofloxacin is an emerging problem in Salmonella enterica in Turkey, particularly in multiresistant strains.

Annual trends in antibiotic resistance of nosocomial Acinetobacter baumannii strains and the effect of synergistic antibiotic combinations.

Acinetobacter baumannii is becoming increasingly resistant to antibiotics often requiring combination therapy. Annual changes of resistance to selected antimicrobials of 150 A. baumannii strains, isolated as nosocomial pathogens between 1994 and 2000 were investigated. The synergistic effects of antimicrobials were studied using a microdilution checkerboard technique in eight selected isolates resistant to third-generation cephalosporins and beta-lactam/beta-lactamase inhibitor combinations and to at least one aminoglycoside. Rates of resistance of cefepime, ceftazidime, ampicillin/sulbactam, amikacin and ciprofloxacin (before 1996 and between 1996-2000) were 29.7% - 72.6, 37.8% - 81.4%, 35.1% - 72.6%, 8.1% - 56.6%, 5.4% - 46.0% respectively (p < 0.001 for each one). Synergy was observed in at least one of the combinations of antibiotics from seven of eight isolates (87%), no antagonism was detected with any combination. Ceftazidime-amikacin (50%) and ampicillin/sulbactam-tobramycin (50%) were the most effective combinations. Due to the effectiveness of sulbactams to Acinetobacter, ampicillin/sulbactam-tobramycin combination is recommended as the first line of choice.

Prevalence of extended-spectrum beta-lactamases produced by nosocomial isolates of Enterobacteriaceae in Trakya University Hospital, Turkey.

The prevalence of extended-spectrum beta-lactamase (ESBL) production by 194 nosocomial isolates of Enterobacteriacea recovered from 1995 to 1999 was investigated. The ESBL production was determined by the double-disk synergy test and was confirmed by the E-test ESBL strip. Twenty-three isolates (21 Klebsiella pneumoniae, one Escherichia coli, one Providencia rettgeri) were found as ESBL-producers (11.8%). These isolates were also usually resistant to non-betalactam antibiotics. Most of them contained a beta-lactamase with a pI of 7.6. All the strains conjugally transferred their ESBLs to recipient E. coli. Contrary to others, ESBL-producing K. pneumoniae strains isolated in 1999 were resistant to ciprofloxacin, and had the identical plasmid profiles suggestive of an outbreak. Ciprofloxacin resistance in these strains could not be transferred. In conclusion, K. pneumoniae was the main ESBL-producing species among nosocomial isolates of Enterobacteriacae in our hospital.

Nebulized surfactant as a treatment choice for otitis media with effusion: an experimental study in the rabbit.

Exogenous surfactant can improve eustachian tube function in experimentally induced otitis media with effusion (OME). Performing tympanometric recordings, the efficacy of inhaled nebulized surfactant, as compared with inhaled nebulized physiological saline was investigated, for the treatment of OME experimentally induced in the rabbit by intrabullar inoculation of heat-killed Streptococcus pneumoniae. In addition, the histological changes in middle ears after the treatment were investigated in order to establish whether the pathological findings correlated with the results. Middle-ear pressure values before, and after, treatment were analyzed by the Wilcoxon statistical method, and the Mann-Whitney U test was used to compare the post-treatment values between groups. In all ears with OME in the affected animals, which were treated with nebulized surfactant inhalation, a positively significant (p<0.05) increase of pressure more than 20 daPa was recorded. In the control group, after inhalation of nebulized physiological saline, there was no positive increase in the affected middle-ear pressures; on the contrary, more negative pressure changes were recorded. In the histological evaluation, middle-ear epithelia and sub-epithelial space were normal in surfactant-treated ears with OME, whereas mucosal thickening with an oedematous sub-epithelial space containing occasional inflammatory cells and increases in connective tissue and vascularity, and effusions on the epithelial surface were present in the ears with OME in the control group. The significant improvement in the negative middle-ear pressure after nebulized surfactant treatment and the histological findings shown in our study can support the theory that surface-active agents are of importance in eustachian tube function even under pathologic conditions, such as OME.

Antibiotic resistance patterns and plasmid profiles of Salmonella typhimurium isolates in Turkey.

To understand the resistance mechanisms present in 75 isolates of Salmonella typhimurium derived from clinical infections in Turkey, antimicrobial resistance patterns and associated plasmids were investigated. Among the 22 strains that produced extended-spectrum beta-lactamase (ESBL), 20 were resistant to aminoglycosides and 12 to trimethoprim-sulfamethoxazole. Strains that did not produce ESBL did not express aminoglycoside or trimethoprim-sulfamethoxazole resistance, although 27 of them were ampicillin resistant. None of the strains were resistant to imipenem or fluoroquinolones. Nineteen strains producing ESBL carried a plasmid of >100 MDa. Seven ESBL-producing strains conjugally transferred their ESBLs and trimethoprim-sulfamethoxazok resistance. No correlation was found between the resistance patterns and plasmids in non-ESBL-producing strains.

Widespread detection of PER-1-type extended-spectrum beta-lactamases among nosocomial Acinetobacter and Pseudomonas aeruginosa isolates in Turkey: a nationwide multicenter study.

We studied the prevalence and molecular epidemiology of PER-1-type beta-lactamases among Acinetobacter, Klebsiella, and Pseudomonas aeruginosa strains isolated over a 3-month period in eight university hospitals from distinct regions of Turkey. A total of 72, 92, and 367 Acinetobacter, Klebsiella, and P. aeruginosa isolates were studied, respectively. The presence of blaPER was determined by the colony hybridization method and later confirmed by isoelectric focusing. We detected PER-1-type beta-lactamases in 46% (33/72) of Acinetobacter strains and in 11% (40/367) of P. aeruginosa strains but not in Klebsiella strains. PER-1-type enzyme producers were highly resistant to ceftazidime and gentamicin, intermediately resistant to amikacin, and susceptible or moderately susceptible to imipenem and meropenem. Among PER-1-type-beta-lactamase-positive isolates, five Acinetobacter isolates and six P. aeruginosa isolates from different hospitals were selected for ribosomal DNA fingerprinting with EcoRI and SalI. The EcoRI-digested DNAs were later hybridized with a digoxigenin-labelled PER-1 probe. The ribotypes and the lengths of blaPER-carrying fragments were identical in four Acinetobacter strains. A single isolate (Ac3) harbored a PER gene on a different fragment (approximately 4.2 kbp) than the others (approximately 3.4 kbp) and showed a clearly distinguishable ribotype. Ribotypes of P. aeruginosa strains obtained with EcoRI showed three patterns. Similarly, in Pseudomonas strains two different EcoRI fragments harbored blaPER (approximately 4.2 kbp in five isolates and 3.4 kbp in one isolate). PER-1-type beta-lactamases appear to be restricted to Turkey. However, their clonal diversity and high prevalence indicate a high spreading potential.

The molecular epidemiology of trimethoprim-sulphamethoxazole- resistance of Shigella flexneri in the Trakya region of Turkey.

Trimethoprim-sulphamethoxazole (SXT) resistance increased among Shigella flexneri isolates in 1995 relative to previous years, in the Trakya region, the European part of Turkey. Since this region is the entrance to Turkey from northern countries, a heavy traffic of travellers passing through should have been importing or exporting the resistant isolates. We studied the genetic basis and epidemiology of this resistance and monitored the clonal changes which have taken place in the meanwhile. During the study period, a total of 70 Shigella spp. were isolated. Of these 58 were S. flexneri, 10 were S. sonnei and two were S. boydii. S. dysenteriae was not isolated. Of S. flexneri isolates 32 were SXT, ampicillin, chloramphenicol and tetracycline resistant (pattern I), while two isolates were found to be resistant only to SXT (Pattern II). Transconjugation experiments revealed that an approximately 80 Kbp self-transmissible plasmid carried the SXT resistance genes in both groups. However, EcoRI and HindIII restriction patterns of the plasmids from resistance pattern I and resistance pattern II were different. Ribotypes of three randomly selected isolates from pattern I were identical and were distinguishable from the ribotype of the isolate from pattern II. We concluded that at least two different clones with different plasmids and resistance patterns were spreading in our territory.