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Staphylococcus aureus superantigens (SAgs) have been reported to aggravate atopic dermatitis. However, comprehensive analyses of these molecules in multiple microniches are lacking. The present study involved 50 adult patients with active atopic dermatitis. S. aureus was isolated from the lesional skin, nonlesional skin, and anterior nares. Multiplex-PCR was performed to identify genes encoding (1) selX (core genome); (2) seg, selI, selM, selN, selO, selU (enterotoxin gene cluster, EGC); and (3) sea, seb, sec, sed, see, tstH (classic SAgs encoded on other mobile genetic elements). The results were correlated to clinical parameters of the study group. selx and EGC were the most prevalent in all microniches. The number of SAg-encoding genes correlated between the anterior nares and nonlesional skin, and between the nonlesional and lesional skin. On lesional skin, the total number of SAg genes correlated with disease severity (total and objective SCORAD, intensity, erythema, edema/papulation, lichenification and dryness). Linear regression revealed that AD severity was predicted only by selx and EGC. This study revealed that selX and EGC are associated with atopic dermatitis severity. Anterior nares and nonlesional skin could be reservoirs of SAg-positive S. aureus. Restoring the physiological microbiome could reduce the SAg burden and alleviate syndromes of atopic dermatitis. [ABSTRACT FROM AUTHOR]

We report the first Polish representative of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), lukS/F-PV-positive, encoding the ermB gene, as a genetic determinant of constitutive resistance to macrolides, lincosamides, and streptogramin B antibiotics, cMLS-B. This is the first detection of the CA-MRSA strain responsible for nosocomial infection in the Warsaw Clinical Hospital. Resistance to β-lactams associates with a composite genetic element, SCCmec cassette type VT (5C2&5). We assigned the strain to sequence type ST338 (single-locus variant of ST59), clonal complex CC59, spa-type t437, and agr-type I. Genomic-based comparison was designated SO574/12 as an international Taiwan clone, which has been so far described mainly in the Asia-Pacific region. The ermB gene locates on the chromosome within the 14,690 bp mobile element structure, i.e., the MESPM1-like structure, which also encodes aminoglycoside- and streptothricin-resistance genes. The MESPM1-like structure is a composite transposon containing Tn551, flanked by direct repeats of IS1216V insertion sequences, which probably originates from Enterococcus. The ermB is preceded by the 273 bp regulatory region that contains the regulatory 84 bp ermBL ORF, encoding the 27 amino acid leader peptides. The latest research suggests that a new leader peptide, ermBL2, also exists in the ermB regulatory region. Therefore, the detailed function of ermBL2 requires further investigations. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis is a chronic inflammatory dermatosis with complex pathogenesis. The skin microbiome in atopic dermatitis is dominated by Staphylococcus aureus which shows the ability to produce biofilm. Objectives: The aim of this work was to assess the influence of S. aureus biofilm on the course of atopic dermatitis. Methods: Disease severity was evaluated based on the SCORAD index in 56 adult patients with atopic dermatitis. Microtiter plate assay of the propensity to form biofilm was performed on S. aureus strains isolated from the anterior nares, lesional skin, and nonlesional skin. Microbiological results were correlated to the clinical parameters and total IgE concentration. Results: Biofilm-producing strains of S. aureus were identified in 76.3% (29/38) and 79.1% (34/43) of samples from the anterior nares and lesional skin, respectively (p > 0.05), and in 48.5% (16/33) of samples from nonlesional skin (p < 0.03). Patients colonized by biofilm-producing strains of S. aureus within the anterior nares showed statistically higher mean values of total and objective SCORAD and its components (extent, dryness), and of the largest extent of skin lesions during the flares in the last year when compared to patients colonized by non-biofilm-producing strains. Carriage of biofilm-producing S. aureus on lesional skin was associated with higher mean values of the extent of skin lesions during stable periods of the disease. Conclusions: The results of this study may suggest a relationship between the production of biofilm by S. aureus strains colonizing the anterior nares and the course of atopic dermatitis. Biofilm seems crucial for dispersal and persistent colonization of large areas of the skin by this pathogen. Destruction of S. aureus biofilm could positively affect the course of atopic dermatitis. [ABSTRACT FROM AUTHOR]

Background. Healthcare-associated infections could affect the rate of morbidity, mortality and postdischarge hospitalization among patients. They are also dangerous to healthcare professionals and generate significant cost to the healthcare system. Objectives. The aim of this study was to evaluate the occurrence rate of colonization with various antibioticresistant (AR) bacteria among patients admitted to the Department of Immunology, Transplantology and Internal Diseases. Material and methods. The study used retrospective analysis of patients (n = 280) with no clinical signs of infection admitted into the department between November 2015 and May 2017. The observational period lasted until January 2019. Collected data included sex, age at admission, location directly prior to current hospitalization, and medical history. Nasal and rectal swabs were collected, and stool and urine samples were obtained on the day of admission. Specimens were cultured according to standard microbiological procedures. In all cases, the appropriate bioMerieux (Marcy-l'Étoile, France) media were used. Isolates were identified using mass spectrometer (Vitek MS; bioMerieux). Results. One-hundred ninety-one (68.2%) of patients were colonized with AR bacteria. The incidence of colonization was not influenced by age or sex. The risk of colonization was associated with admission from another hospital and history of kidney transplantation (p = 0.0136 and p < 0.001, respectively). The number of hospitalizations during the whole observational period was higher in the group of colonized patients compared to non-colonized (2.76 ±2.4 vs 2.07 ±1.68, p = 0.0099). The number of hospitalizations correlated positively with the number of positive cultures obtained from the same patients (rho = 0.18, p = 0.0274). Conclusions. The rate of colonization at admission to the ward could be high, depending on previous hospitalization and medical history. Colonization significantly increased post-discharge hospitalization rate. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis (AD) is a highly pruritic skin condition of unclear pathogenesis. Patients with AD are predisposed to colonization by Staphylococcus aureusdue to deficiencies in the mechanical and immunological functions of the skin barrier. Recent studies indirectly show that S. aureus may aggravate disease flares in AD. Aims: The aim was to assess the relationship between S. aureus skin colonization and itch intensity in patients with AD. Materials and Methods: The SCORAD index components reflecting itch intensity (excoriations, subjective evaluation of pruritus, and sleep loss) were assessed in 33 adult patients with AD. Swabs were taken from lesional and nonlesional skin. The prevalence and abundance of S. aureus were assessed. Statistical analysis was performed to correlate the microbiological results with the clinical parameters. The control group consisted of 36 healthy volunteers. Results: Lesional and nonlesional skin showed a high frequency of S. aureus colonization when compared with controls (81.8% and 57.6% vs 5.6%, respectively, P< 0.0001). The mean concentration (points) of S. aureus was 2.01 ± 1.25, 1.06 ± 1.14, and 0.11 ± 0.46, respectively (P< 0.0001). S. aureus abundance on lesional/nonlesional skin positively correlated with excoriations and sleep loss (rho = 0.69, P< 0.00001; rho = 0.44, P< 0.01; rho = 0.41, P< 0.02; and rho = 0.34, P< 0.05, respectively). The mean values of excoriations were higher in patients colonized by S. aureus than in patients without S. aureus carriage. Conclusion: S. aureus skin colonization may be one of the factors aggravating itch in AD. It may be hypothesized that restoring the natural composition of the skin microbiome may reduce pruritus intensity. [ABSTRACT FROM AUTHOR]

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Copyright of Epidemiological Review / Przegląd Epidemiologiczny is the property of National Institute of Public Health - National Institute of Hygiene and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Purpose: Human adenoviruses (HAdV) from species A, B and C are commonly recognized as pathogens causing severe morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. The purpose of the present study was to determine HAdV types responsible for viremia in HSCT recipients at a large tertiary hospital in Poland. Methods: Analysis of partial nucleotide sequences of HAdV hexon gene was used to type 40 clinical isolates of HAdV obtained from 40 HSCT recipients. Results: We identified six different HAdV serotypes belonging to species B, C and E. We demonstrated high variability in sequences of detected HAdV types, and patients infected with the same HAdV types were not hospitalized at the same time, which suggests the low possibility of cross-infection. In almost all patients, anti-HAdV antibodies in IgG class were detected, which indicates a history of HAdV infection in the past. Clinical symptoms accompanying HAdV viremia were in 89%, and in 61.5% of individuals, HAdV was a sole pathogen detected. There were no cases with high-level HAdV viremia and severe systemic or organ infections. Graft-versus-host disease (GvHD) was present in patients infected with species B and C, but grade II of GvHD was observed only in patients infected with HAdV-B. Conclusions: The predominance of HAdV-C and common presence of anti-HAdV antibodies in IgG class may strongly suggest that most infections in the present study were reactivations of HAdV persisting into the patient’s mucosa-associated lymphoid tissues. Variability of HAdV sequences suggests that cross-infections between patients were very rare. ABBREVIATIONS: GvHD: graft-versus-host disease; HAdV: human adenoviruses; HSCT: hematopoietic stem cell transplantation [ABSTRACT FROM AUTHOR]

Introduction: One of two main mechanisms of resistance in tetracycline-resistant Neisseria gonorrhoeae (TRNG) is associated with the presence of TetM protein responsible for actively blocking of the tetracycline target site in the 30S ribosomal subunit. This mechanism is encoded by conjugative plasmids. The second mechanism is chromosomal in nature and due to mutations in specific genes. Aim: To determine the incidence and type of tetM determinants in TRNG strains isolated from patients presenting with gonorrhea infection to the Dermatology and Venereology Clinic in Warsaw in 2012-2013. Material and methods: Tetracycline and doxycycline susceptibility was determined by E-Tests. The presence and type of the tetM gene were determined by polymerase chain reaction. Results: Tetracycline resistance was detected in 50.8% of the evaluated strains. The TRNG strains containing the tetM plasmid constituted 13.8% of all the evaluated strains. Dutch type tetM constituted 12.3% and American type tetM 1.5% of all the evaluated strains. In the remaining TRNG strains, resistance to tetracyclines was presumably chromosome-encoded. The minimal inhibitory concentration (MIC) of tetracycline ranged from 0.25 to 32.0 mg/l, MIC50 = 2.0 mg/l, MIC90 = 32.0 mg/l. The MIC of doxycycline ranged from 0.25 to 32.0 mg/l, MIC50 = 4.0 mg/l, MIC90 = 16.0 mg/l. Conclusions: Unlike most of European countries, in 2012-2013 in Poland, the Dutch type tetM was found to be much more common than the American type. Minimal inhibitory concentration values of tetracycline and doxycycline were similar, with doxycycline exhibiting a somewhat lower effectiveness in vitro than tetracycline towards chromosome-mediated tetracycline resistant strains of N. gonorrhoeae. [ABSTRACT FROM AUTHOR]

There are no specific antivirals designed for adenoviral infections. Due to many cases of adenovirus infections worldwide, epidemic nature of some types of adenoviruses, and growing number of patients with severe adenoviral infections resulting from dysfunction the immune system, the need for searching an effective and safe therapy is increasing. Inosine pranobex exerts antiviral effects which are both direct and secondary to immunomodulatory activity. In the present study we evaluated in vitro effect of inosine pranobex and interferon α (IFN-α) on replication of HAdV-2 and HAdV-5. The effectiveness of inosine pranobex under these conditions has not been previously reported. In conducted study we reported that inosine pranobex reduced the titer of infectious HAdV-2 and HAdV-5 in vitro. Higher concentrations of IP strongly inhibited multiplication of viruses. Combination of inosine pranobex and IFN-α display higher efficacy than either treatment alone and suggest that both agents may increase therapeutic effectiveness without augmenting toxic effects. Combination index calculations showed that inosine pranobex and INF-α synergistically inhibit HAdV-2 and HAdV-5 titers in A549 cells. [ABSTRACT FROM AUTHOR]

In the search for new antimicrobial and anticancer agents, a series of (aryl/heteroaryl-piperazino-alkyl)-substituted derivatives of benzo[ b]furans were prepared. All compounds were characterized by 1H NMR, 13C NMR, ESI-MS spectra and elemental analyses. Most of the investigated compounds had no antimicrobial activity (MIC > 512 mg/L) except for 2l, 2m and 2o, which showed activity against Candida albicans. None of the tested compounds showed significant anticancer activity in K562 and HeLa cells. [ABSTRACT FROM AUTHOR]

Five aminoalkyl 1 H-benzo[ de]isoquinoline-1,3(2 H)-diones were synthesized and evaluated for antimicrobial activity. Microorganisms used in this study included aerobic and facultative anaerobic bacteria Staphylococcus aureus, Escherichia coli and Stenotrophomonas maltophilia, and obligatory anaerobes Bacteroides fragilis, Bacteroides thetaiotaomicron and Propionibacterium acnes. Moreover, Candida albicans yeast was used. The minimum inhibitory concentration (MIC) was determined for the test compounds. Among the tested derivatives, two compounds 1 and 2 have shown the most potent antibacterial as well as antifungal activities. [ABSTRACT FROM AUTHOR]

Background: Urinary tract infections (UTIs) are the most common bacterial infections among kidney transplant (KTX) recipients. The purpose of this study was to analyze antimicrobial resistance (AMR) in four most common pathogens responsible for UTIs in KTX recipients and determine risk factors (RF) for resistance in the same group. Methods: Analyzed antibiograms were based on urine samples positive for bacterial growth of 105 colony-forming units (CFU)/mL obtained from hospitalized adult KTX recipients presenting with UTI symptoms upon admission to the center in years 2011–2018. Results: In total, 783 antibiograms were analyzed for Klebsiella pneumoniae (258 samples, 33.0%), Escherichia coli (212, 27.0%), Enterococcus faecalis (128, 24.0%), and Enterococcus faecium (125, 16.0%). The decrease in susceptibility of E. coli to amoxicillin/clavulanic acid (62.9% vs. 40.0%) and ciprofloxacin (100% to 40.0%) was observed. Susceptibility to gentamicin increased from 33.3% to 92.9% in E. faecium. Susceptibility to tigecycline remained 100% through all years in case of E. faecalis and E. faecium. Male gender was a RF for resistance to amoxicillin/clavulanic acid (p = 0.008), ciprofloxacin (p = 0.0003), trimethoprim/sulfamethoxazole (p = 0.00009), ceftriaxone (p = 0.0001), and cefuroxime axetil (p = 0.00038) in K. pneumoniae and against gentamicin in E. faecalis (p = 0.015). Higher resistance to ampicillin in E. faecalis (p = 0.012) and to ciprofloxacin (p = 0.0003), trimethoprim/sulfamethoxazole (p = 0.007), piperacillin/tazobactam (p = 0.003), ceftriaxone (p = 0.001), and cefuroxime axetil (p = 0.013) in K. pneumoniae was observed in higher age groups of patients. Diabetes as a cause of kidney insufficiency (p = 0.026) and kidney-pancreas transplantation (p = 0.014) was RF for resistance to ceftriaxone in K. pneumoniae. Conclusions: AMR in uropathogens from KTX recipients fluctuated. There were identifiable RFs for resistance in the examined bacteria–antibiotic combinations. We recommend continuous mapping of site-specific microorganisms as etiology and susceptibility may vary between institutions and over time. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis (AD) is exacerbated by Staphylococcus aureus, which is capable of displacing not only the physiological microbiota, but also other strains of its own species. Analyses of the molecular characteristics and relationships of S. aureus strains present in different microniches are lacking., Objectives: To determine, using multilocus sequence typing (MLST), the relationship of S. aureus isolates from the lesional and nonlesional skin and anterior nares of patients with AD, and to review the characteristics of the dominant clones., Methods: Sixty-three individuals with active AD were enrolled. Ten patients with moderate-to-severe AD (SCoring of Atopic Dermatitis score ≥ 25) colonized by S. aureus in all analysed locations were included in the MLST analysis., Results: The most prevalent sequence types were 7 (10/30 strains; 33.3%), 15 and 97 (both 5/30 strains; 16.7%) all of which were associated with the expression of adhesins and toxins promoting chronic microbial dysbiosis, skin barrier damage and inflammation. Six patients (60%) were carriers of clonal S. aureus strains at all analysed locations, three (30%) carriers in lesional and nonlesional skin, and one (10%) was a carrier in nonlesional skin and the anterior nares., Conclusions: The results imply that the identified S. aureus lineages are better adapted to dominate the microbiota in AD. Decontaminating the identified reservoirs of S. aureus (i.e. anterior nares and nonlesional skin) could reduce the severity of AD., Competing Interests: Conflicts of interest The authors state no conflict of interest related to the present work., (© The Author(s) 2023. Published by Oxford University Press on behalf of British Association of Dermatologists. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Staphylococcus aureus is a microorganism, which is able to colonize the human body without any pathogenic effect, but it also can cause life-threatening infections (opportunistic pathogen). Asymptomatic colonization with both methicillin resistant (MRSA) and methicillin susceptible (MSSA) S.aureus strains state is an important predisposing factor for infections. The risk of infection for carriers of MSSA is even three-times higher than for non-colonized people, and in the case of MRSA it is even four-times higher than in MSSA carriers. Carriers can be also a source of infection for other people, especially those belonging to high-risk groups. The drug of choice used for the local eradication of S.aureus is mupirocin (Mup). In recent years, the failure of decolonization therapy has been observed. The aim of the study was to assess and compare the level of colonization of S.aureus (MRSA or MSSA) among medical students and to evaluate the sensitivity of the strains to mupirocin. For MRSA/MupRSA isolates the molecular mechanism of resistance phenotype was determined., Materials and Methods: 955 swabs from 2014-2016 from pre-clinical students of medicine of the Medical University of Warsaw. The strains were identified using Pastorex-Staph-Plus (BioRad) and/or the VITEK-MS system (Biomerieux), according to manufacturer’s instructions. Susceptibility to methicillin and mupirocin was determined by disk diffusion and/or broth microdilution method, according to EUCAST. The presence of the mecA/mecC and mupA genes were detected with PCR technique., Results: Asymptomatic colonization with S.aureus strains was found in 245/955 (25,7%) students, in particular years in the range of 21,7-29,9%. 243 isolates expressed the MSSA/MupSSA phenotype, one strain was resistant to mupirocin MSSA/MupRSA (genotype mecA/mecC-negative, mupA-positive) and one showed simultaneous resistance to methicillin and mupirocin (mecA/mupA-positive genotype). The level of MRSA and MupRSA colonization was 0,1% and 0,2%, respectively., Summary and Conclusions: The level of S.aureus colonization among surveyed students, didn’t differ from the norm for a generally healthy population, but showed an upward trend. The carriage of S.aureus, especially of multi-resistant strains among medical students at the beginning of their clinical activities, consist of a real threat to patients and other people.

Introduction: Staphylococcus aureus, which is able to produce an extracellular mucopolysaccharide (MP) and biofilm (SP), is an important etiologic agent in persistent and implant-related infections. This phenotype may be expressed in different levels and character depending on various environmental and/or global intracellular regulatory mechanisms. It may also be induced by sub-inhibitory concentrations of some antibiotics, for example vancomycin. The main aim of the study was to assess the ability to produce MP and SP in different oxygen conditions by clinical isolates of S.aureus nonsusceptible to glycopeptides., Materials and Methods: Clinical isolates of health-care associated methicillin resistant S. aureus (HA-MRSA) strains, non-susceptible to glycopeptides (GRSA, 47) and heterogeneous vancomycin intermediate S. aureus isolates (h-VISA, 8). Control group consisted of the following strains: 55 belonging to MRSA, vancomycin susceptible, VSSA and 19 as methicillin susceptible, MSSA/VSSA. The ability to produce MP was investigated according to Freeman method. SP production was tested by means of Christensen procedure., Results: In aerobic conditions MRSA/GRSA and MRSA/h-VISA isolates were the strongest mucopolysaccharide (SMP) producers (12.2% and 28.6% SMP/MP), but MSSA/VSSA were the most frequent MP (100%). In anaerobic atmosphere, all isolates from all groups were MP-positive. MRSA/h-VISA were the strongest MP producers (75% SMP/MP), but MSSA/VSSA were the most susceptible to oxidative stress (the percentage of SMP among MP for MSSA/VSSA increased by 15.8 times). Each evaluated group of clinical S. aureus isolates in aerobic condition had representation in SP positive phenotype: MRSA/GRSA and MRSA/h-VISA, 63.9% and 62.5%; MRSA/VSSA and MSSA/VSSA, respectively 80% and 94.7%. For all mentioned groups of bacteria, SSP variants were present and the amount of values was higher than in similar results obtained in CRA method. The strongest slime producers (60%) were h-VISA strains. The results obtained in Christensen method for anaerobic conditions, were not conclusive due to insufficient optimization of the test parameters., Summary and Conclusions: Both methods reveal that MRSA isolates non-susceptible to glycopeptides are the strongest producers of both MP and SP. That is probably due to cell wall alterations and global regulatory system Agr disorders. The Christensen procedure allow to assess both ica- dependent and ica- independent (adhesive) mechanisms of slime production and allow to notice that, as a phenotyping “biofilm booster effect”. ica- dependent mechanism, which dominated in MSSA/VSSA strains, demonstrate phenotype with more susceptibility to oxygen stress conditions than adhesive one.

Introduction: One of two main mechanisms of resistance in tetracycline-resistant Neisseria gonorrhoeae (TRNG) is associated with the presence of TetM protein responsible for actively blocking of the tetracycline target site in the 30S ribosomal subunit. This mechanism is encoded by conjugative plasmids. The second mechanism is chromosomal in nature and due to mutations in specific genes., Aim: To determine the incidence and type of tetM determinants in TRNG strains isolated from patients presenting with gonorrhea infection to the Dermatology and Venereology Clinic in Warsaw in 2012-2013., Material and Methods: Tetracycline and doxycycline susceptibility was determined by E-Tests. The presence and type of the tetM gene were determined by polymerase chain reaction., Results: Tetracycline resistance was detected in 50.8% of the evaluated strains. The TRNG strains containing the tetM plasmid constituted 13.8% of all the evaluated strains. Dutch type tetM constituted 12.3% and American type tetM 1.5% of all the evaluated strains. In the remaining TRNG strains, resistance to tetracyclines was presumably chromosome-encoded. The minimal inhibitory concentration (MIC) of tetracycline ranged from 0.25 to 32.0 mg/l, MIC 50 = 2.0 mg/l, MIC 90 = 32.0 mg/l. The MIC of doxycycline ranged from 0.25 to 32.0 mg/l, MIC 50 = 4.0 mg/l, MIC 90 = 16.0 mg/l., Conclusions: Unlike most of European countries, in 2012-2013 in Poland, the Dutch type tetM was found to be much more common than the American type. Minimal inhibitory concentration values of tetracycline and doxycycline were similar, with doxycycline exhibiting a somewhat lower effectiveness in vitro than tetracycline towards chromosome-mediated tetracycline resistant strains of N. gonorrhoeae ., Competing Interests: The authors declare no conflict of interest.

As part of the European Clostridium difficile infections (CDI) surveillance Network (ECDIS-Net), which aims to build capacity for CDI surveillance in Europe, we constructed a new network of hospital-based laboratories in Poland. We performed a survey in 13 randomly selected hospital-laboratories in different sites of the country to determine their annual CDI incidence rates from 2011 to 2013. Information on C. difficile laboratory diagnostic testing and indications for testing was also collected. Moreover, for 2012 and 2013 respectively, participating hospital-laboratories sent all consecutive isolates from CDI patients between February and March to the Anaerobe Laboratory in Warsaw for further molecular characterisation, including the detection of toxin-encoding genes and polymerase chain reaction (PCR)-ribotyping. Within the network, the mean annual hospital CDI incidence rates were 6.1, 8.6 and 9.6 CDI per 10,000 patient-days in 2011, 2012, and 2013 respectively. Six of the 13 laboratories tested specimens only on the request of a physician, five tested samples of antibiotic-associated diarrhoea or samples from patients who developed diarrhoea more than two days after admission (nosocomial diarrhoea), while two tested all submitted diarrhoeal faecal samples. Most laboratories (9/13) used tests to detect glutamate dehydrogenase and toxin A/B either separately or in combination. In the two periods of molecular surveillance, a total of 166 strains were characterised. Of these, 159 were toxigenic and the majority belonged to two PCR-ribotypes: 027 (n=99; 62%) and the closely related ribotype 176 (n=22; 14%). The annual frequency of PCR-ribotype 027 was not significantly different during the surveillance periods (62.9% in 2012; 61.8% in 2013). Our results indicate that CDIs caused by PCR-ribotype 027 predominate in Polish hospitals participating in the surveillance, with the closely related 176 ribotype being the second most common agent of infection.

Background: Transmission of pathogens via preservation fluid (PF) is a potential cause of infection among liver transplant recipients. Here, we evaluated the incidence and pattern of microbial contamination of PF and its impact on postoperative graft function after liver transplantation., Material/methods: This longitudinal study included data from 41 primary liver transplantations and 5 re-transplantations performed between December 2010 and September 2011. Results of microbiological analyses of 92 PF samples collected before and after the back-table procedure were evaluated in order to establish the incidence and pattern of contamination. The impact of positive PF cultures on early graft function and rate of pathogen transmission was assessed. Post-transplant antibiotic protocol was based on piperacillin/tazobactam administration for a minimum of 10 days., Results: The incidence of contamination was 84.8% (39/46), both for samples collected before and after the back-table procedure. Gram-positive low-virulence organisms typical for superficial saprophytic flora, mainly coagulase-negative staphylococci, were predominant. There were no cases of pathogen transmission from PF to the recipient. Positive cultures of PF samples obtained after the back-table procedure were associated with significant elevation of aspartate (p=0.034) and alanine aminotransferase (p=0.048) on the first 5 postoperative days. No significant differences were found regarding serum bilirubin concentration (p=0.335) and international normalized ratio (p=0.137)., Conclusions: Despite high incidence of PF contamination, infections caused by pathogens isolated from PF were not observed. However, presence of pathogens in PF might lead to temporary impairment of graft function.