Activity of Ceftolozane/Tazobactam Against Gram-Negative Rods of the Family Enterobacteriaceae and Pseudomonas Spp. Isolated from Onco-Hematological Patients Hospitalized in a Clinical Hospital in Poland.

BACKGROUND The most common etiological agents of infections in onco-hematological patients are Gram-negative rods resistant to many antimicrobials, including carbapenems. Recently, ceftolozane combined with tazobactam became a novel therapeutic option. The aim of the present study was to analyze the susceptibility to ceftolozane/tazobactam of the clinical strains of these bacteria. MATERIAL AND METHODS Material comprised rectal swabs, urine, and bronchoalveolar lavage fluid obtained from onco-hematological patients hospitalized in a clinical hospital (1050 beds) in Poland. Identification of the isolated bacteria was done by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using the MALDI Biotyper (Bruker). Ceftolozane/tazobactam susceptibility of the isolates was assessed using antimicrobial gradient strips (E-test, BioMérieux). Antimicrobial susceptibility testing and interpretation of the results was done according to the current recommendations of the European Committee on Antimicrobial Susceptibility Testing (EUCAST). RESULTS In total, 281 rectal swabs and 116 urine samples were tested for the presence of Gram-negative rods producing ESBL, and 531 rectal swabs and 8 bronchoalveolar lavage fluid samples were tested for the presence of Gram-negative rods resistant to carbapenems. In the analyzed period, 69 non-repetitive strains of bacteria were isolated that were in the spectrum of activity of ceftolozane/tazobactam. Among 44 clinical strains of ESBL(+) Enterobacteriaceae rods, 76% were susceptible to ceftolozane/tazobactam. All 9 strains of non-carbapenemase-producing P. aeruginosa resistant or with decreased susceptibility to carbapenems were susceptible to ceftolozane/tazobactam. CONCLUSIONS Ceftolozane/tazobactam may be an option in the therapy of infections caused by ESBL(+) strains of Enterobacteriaceae as well as non-carbapenemase-producing carbapenem-resistant strains of P. aeruginosa.

Detection of Polish clinical Aspergillus fumigatus isolates resistant to triazoles.

We studied the presence of triazole resistance of 121 Aspergillus fumigatus clinical isolates collected in two Polish cities, Warsaw and Wroclaw, to determine if resistance is emerging in our country. We identified five itraconazole resistant isolates (4.13%) carrying the TR34/L98H alteration in Cyp51A gene, four of which were cross-resistant to posaconazole and one to voriconazole. One isolate was intermediate susceptible to itraconazole and harbored no Cyp51A alterations. The study confirms the presence of azole resistant A. fumigatus strains in Poland at a level that is comparative to other European countries.

Fournier's Gangrene: Clinical Presentation of 13 Cases.

BACKGROUND Fournier's gangrene (FG) is a fulminant form of infective, polymicrobial, necrotizing fasciitis of the perineal, genital, and perianal regions. It commonly affects men, but women and children may also develop this type of tissue necrosis. MATERIAL AND METHODS This study is a retrospective analysis of the management of 13 cases of Fournier's gangrene, diagnosed from among about 45 000 patients (men, women, and children) treated in the Department of General, Oncological, and Functional Urology (Medical University of Warsaw) from 1995 to 2013. All patients with Fournier's gangrene underwent adequate surgical debridement of the necrotic tissues. Additional procedures (suprapubic cystostomy and orchiectomy) were necessary in 10 out of 13 (77.0%) patients. Seven out of 13 (53.8%) patients required subsequent reconstructive surgery of the scrotum. RESULTS All 13 patients were males, with a median age of 59.6 years (range: 42-68 years). The average hospital stay was 31.9 days (range: 16-46 days). None of our patients died due to Fournier's gangrene. Bacteriological cultures of samples from the wounds showed polymicrobial flora, including the following genera of aerobes and anaerobes: Escherichia, Proteus, Klebsiella, Moraxella, Gemella, Enterococcus, Streptococcus, Staphylococcus, Bacteroides, Pseudoflavonifractor, Parabacteroides, Porphyromonas, Prevotella, Peptoniphilus, Peptostreptococcus, Actinomyces, Collinsella, and Lactobacillus. CONCLUSIONS Favorable outcome of FG treatment with low morbidity and no mortality can be achieved with rapid diagnosis, urgent surgical debridement of all necrotic tissues, and broad-spectrum empirical antimicrobial therapy, usually with combined antibiotics, against aerobic and anaerobic bacteria. Prevention of uroseptic shock by treating localized infection is compulsory.

Fecal Microbiota Transplantation in Patients With Blood Disorders Inhibits Gut Colonization With Antibiotic-Resistant Bacteria: Results of a Prospective, Single-Center Study.

Background: Patients with blood disorders colonized with antibiotic-resistant bacteria (ARB) are prone to systemic infections that are difficult to treat. Reintroduction of commensal bacteria in a murine model of enterococcal colonization of the gut can lead to eradication of enterococci. We hypothesized that fecal microbiota transplantation (FMT) could be used to eradicate ARB in humans. Methods: Participants colonized with ARB were treated with intraduodenal FMT according to a prospective protocol (NCT02461199). The primary endpoint was complete ARB decolonization at 1 month after FMT. Secondary endpoints included safety assessment and partial ARB decolonization. Microbiome sequencing was performed to investigate the influence of microbial composition of the transplanted material on the outcome of FMT. Results: Twenty-five FMTs were performed in 20 participants (including 40% who had neutropenia) who were colonized by a median of 2 (range, 1-4) strains of ARB. The primary endpoint was reached in 15/25 (60%) of the FMTs and more frequently in cases in which there was no periprocedural use of antibiotics (79% vs 36%, P < .05). Among participants, 15/20 (75%) experienced complete ARB decolonization. There were no severe adverse events, and partial ARB decolonization was observed in 20/25 (80%) of the FMTs. The microbiota composition analysis revealed higher abundance of Barnesiella spp., Bacteroides, and Butyricimonas and greater bacterial richness in the fecal material, resulting in eradication of Klebsiella pneumoniae compared with nonresponders. Conclusions: FMT in patients with blood disorders is safe and promotes eradication of ARB from the gastrointestinal tract. Clinical Trials Registration: NCT02461199.

Application of Metagenomic Analyses in Dentistry as a Novel Strategy Enabling Complex Insight into Microbial Diversity of the Oral Cavity.

The composition of the oral microbiome in healthy individuals is complex and dynamic, and depends on many factors, such as anatomical location in the oral cavity, diet, oral hygiene habits or host immune responses. It is estimated at present that worldwide about 2 billion people suffer from diseases of the oral cavity, mainly periodontal disease and dental caries. Importantly, the oral microflora involved in local infections may spread and cause systemic, even life-threatening infections. In search for etiological agents of infections in dentistry, traditional approaches are not sufficient, as about 50% of oral bacteria are not cultivable. Instead, metagenomic analyses are particularly useful for studies of the complex oral microbiome - both in healthy individuals, and in patients with oral and dental diseases. In this paper we review the current and future applications of metagenomic studies in evaluation of both the composition of the oral microbiome as well as its potential pathogenic role in infections in dentistry.

Periapical abscess ­ etiology, pathogenesis and epidemiology

Inflammation of the pulp and periapical tissues is the main cause of tooth loss in patients worldwide, therefore endodontics is one of the most rapidly developing specialties in dentistry. Despite proper endodontic treatment, in many cases it is not possible to determine the etiology of infection or the reason for its relapse. Many research studies indicate that infections of the periapical tissues are mainly caused by strictly anaerobic bacteria. At present, more and more often the composition of the microflora within the inflammatory lesions is being evaluated with the use of molecular techniques, which showed that classical culture methods are not able to determine the etiology of infections of the periapical tissues. The results of these studies contributed to the major changes in our understanding of the microbiome composition in the endodontium. Purulent endodontic lesions are particularly important, as they may lead to many severe ­ even life-threatening ­ systemic complications.

Impact of Gut Colonization by Antibiotic-Resistant Bacteria on the Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation: A Retrospective, Single-Center Study.

Gut colonization by antibiotic-resistant bacteria may underlie hard-to-treat systemic infections. There is also accumulating evidence on the immunomodulatory function of gut microbiota after allogeneic stem cell transplantation (alloSCT) and its impact on graft-versus-host disease (GVHD). We investigated the epidemiology and clinical impact of gut colonization after alloSCT and retrospectively analyzed data on 107 alloSCTs performed at a single transplant center. Pretransplant microbiology screening identified colonization in 31% of cases. Colonization had a negative impact on overall survival after alloSCT in univariate (34% versus 74% at 24 months, P < .001) and multivariate (hazard ratio, 3.53; 95% confidence interval, 1.71 to 7.28; P < .001) analyses. Nonrelapse mortality was significantly higher in colonized than in noncolonized patients (42% versus 11% at 24 months, P = .001). Colonized patients more frequently experienced bacteremia (48% versus 24%, P = .01), and more deaths were attributable to infectious causes in the colonized group (42% versus 11% of patients and 67% versus 29% of deaths, P < .05). We observed a significantly higher incidence of grades II to IV acute GVHD in colonized than in noncolonized patients (42% versus 23%, P < .05), especially involving the gastrointestinal system (33% versus 13.5%, P = .07). In summary, we determined that gut colonization by antibiotic-resistant bacteria decreases the overall survival of patients undergoing alloSCT by increasing nonrelapse mortality and the incidences of systemic infection and acute GVHD.

Aspergillosis of the Heart and Lung and Review of Published Reports on Fungal Endocarditis.

Invasive aspergillosis (IA) is increasingly diagnosed in high-risk patients. The lesions are usually located in the lungs and/or sinuses, and the fungus may spread haematogenously to different organs; however, involvement of the heart during IA is very rare. We describe a unique case of invasive aspergillosis of the heart septum and the lungs in the allogeneic haematopoietic stem cell transplant recipient.

[Frequency of detection of soluble antigens of Candida spp. and Aspergillus spp. using serological assays in body fluids of patients of Central Clinical Hospital in Warsaw].

INTRODUCTION: Immunodeficient patients, e.g. transplant recipients, patients treated with corticosteroids, people with AIDS and individuals undergoing prolonged antibiotic therapy are at high risk of invasive fungal infections, especially invasive aspergillosis. Basic method for detection of organ/systemic fungal infection is serological monitoring in body fluids, first of all in serum, bu also in broncho-alveolar lavages (BALF). Proven invasive fungal infection should be diagnosed by culture of the pathogen or histopathological examination of infected tissues, however the detection of soluble fungal antigens in body fluids gives enough information for diagnosis of probable fungal infection, according to European Organization for Research and Treatment of Cancer recommendations, what allows introduction of antifungal therapy. Aim of the study was to asses the frequency of detection of circulation soluble fungal antigens with use of immunoenzymatic techniques in patients hospitalized between 2010 and 2015 in Independent Public Central Clinical Hospital (IPCCH) in Warsaw. Methods: In IPCCH, between 2010 and 2015, 6475 serum samples, taken from 2096 patients, was tested for Candida spp. mannan antigen, and 7745 sera from 2243 patients were tested for Candida spp. mannan antigen, and 7745 sera from 2243 patients were tested for galactomannan antigen of Aspergillus spp, as well as 64 samples of BALF. Material was collected mainly from haematopoietic stem cell transplant recipients, hospitalized in Haematology and Oncology Clinics, during their routine pos-transplant monitoring. Testing was performed with use of quantitative (Candida antigen) or semiquantitative (Aspergillus antigen) immunoenzymatic methods (BioRad-Platelia), according to respective protocols. Results: During examined period, increase in number of examinations was observed, starting from 1311 tests performed in 2010, up to 3052 examination in 2015. In 2015 testing for Aspergillus antigen in BALF samples was also introduced, resulting in 64 samples tested. Candida spp. antigen was detected in 171 samples (2,7% of all tested samples), and Aspergillus galactomannan was detected in 645 serum samples (8,4%) and 8 BALF samples (12,5%). Majority of examinations was performed for patients hospitalized in Haematology and Oncology Clinics (72,7%), Blood Vessel Surgery and Transplantology Clinics (3,8%), as well as in patients under care of post-transplantation (8,3%) and haematology (4,2%) out-patients clinics. Conclusions: (i) In the 2015-2015 visible increase in number of fungal antigens examinations was observed, (ii) significant number of examinations was performed in onco-haematological patients (88,7%), what also indicates main risk group, (iii) 8,3% of fungal antigen testing was performed in solid organ transplant recipients, the second risk group for invasive fungal infection.

Bactericidal activities of cathelicidin LL-37 and select cationic lipids against the hypervirulent Pseudomonas aeruginosa strain LESB58.

Pseudomonas aeruginosa Liverpool epidemic strain (LES) infections in cystic fibrosis (CF) patients are associated with transmissibility and increased patient morbidity. This study was designed to assess the in vitro activities of cathelicidin LL-37 peptide (LL-37) and select cationic lipids against Pseudomonas aeruginosa LESB58 in CF sputum and in a setting mimicking the CF airway. We found that LL-37 naturally present in airway surface fluid and some nonpeptide cationic lipid molecules such as CSA-13, CSA-90, CSA-131, and D2S have significant, but broadly differing, bactericidal activities against P. aeruginosa LESB58. We observed strong inhibition of LL-37 bactericidal activity in the presence of purified bacteriophage Pf1, which is highly expressed by P. aeruginosa LES, but the activities of the cationic lipids CSA-13 and CSA-131 were not affected by this polyanionic virus. Additionally, CSA-13 and CSA-131 effectively prevent LESB58 biofilm formation, which is stimulated by Pf1 bacteriophage, DNA, or F-actin. CSA-13 and CSA-131 display strong antibacterial activities against different clinical strains of P. aeruginosa, and their activities against P. aeruginosa LESB58 and Xen5 strains were maintained in CF sputum. These data indicate that synthetic cationic lipids (mimics of natural antimicrobial peptides) are suitable for developing an effective treatment against CF lung P. aeruginosa infections, including those caused by LES strains.

Polyelectrolyte-mediated increase of biofilm mass formation.

BACKGROUND: Biofilm formation is associated with various aspects of bacterial and fungal infection. This study was designed to assess the impact of diverse natural polyelectrolytes, such as DNA, F-actin, neurofilaments (NFs), vimentin and purified Pf1 bacteriophage on biofilm formation and swarming motility of select pathogens including Pseudomonas aeruginosa associated with lung infections in CF patients. RESULTS: The bacteriophage Pf1 (1 mg/ml) significantly increased biofilm mass produced by Pseudomonas aeruginosa P14, Escherichia coli RS218 and Bacillus subtilis ATCC6051. DNA, F-actin, NFs and Pf1 also increased biofilm mass of the fungal C. albicans 1409 strain. Addition of F-actin, DNA or Pf1 bacteriophage to 0.5% agar plates increased swarming motility of Pseudomonas aeruginosa Xen5. CONCLUSIONS: The presence of polyelectrolytes at infection sites is likely to promote biofilm growth and bacterial swarming.

Significance of biofilms in dentistry.

In the past decades significant scientific progress has taken place in the knowledge about biofilms. They constitute multilayer conglomerates of bacteria and fungi, surrounded by carbohydrates which they produce, as well as substances derived from saliva and gingival fluid. Modern techniques showed significant diversity of the biofilm environment and a system of microbial communication (quorum sensing), enhancing their survival. At present it is believed that the majority of infections, particularly chronic with exacerbations, are a result of biofilm formation, particularly in the presence of biomaterials. It should be emphasised that penetration of antibiotics and other antimicrobial agents into deeper layers of a biofilm is poor, causing therapeutic problems and necessitating sometimes removal of the implant or prosthesis. Biofilms play an increasing role in dentistry as a result of more and more broad use in dental practice of plastic and implantable materials. Biofilms are produced on the surfaces of teeth as dental plaque, in the para-nasal sinuses, on prostheses, dental implants, as well as in waterlines of a dental unit, constituting a particular risk for severely immunocompromised patients. New methods of therapy and prevention of infections linked to biofilms are under development.

Fournier's gangrene--current concepts.

Fournier's gangrene (FG) is a rapidly progressive form of infective necrotising fasciitis of the perineal, genital, or perianal regions, leading to thrombosis of the small subcutaneous vessels and necrosis of the overlying skin. It is believed that the occurrence of the disease in women is underreported and may be unrecognised by some clinicians. Fournier's gangrene is a life-threatening condition, constituting an urological emergency. Many patients with Fournier's gangrene have medical or surgical conditions, which are predisposing factors to this disease or its more severe or fatal course. These comprise diabetes mellitus, hypertension, alcoholism and advanced age. Recent reports in the literature point to changes in the epidemiology of FG, comprising an increasing age of patients. Several authors reported that the mean age of FG patients is at present 53-55 years. Prognosis in FG patients is based on FGSI (Fournier's gangrene severity index) score. Despite the progress in medical care for FG patients, the mortality rate reported in the literature remains high--most often 20-40%, but ranges from 4% to 80%. The most common isolates cultured from FG lesions are both Gram-positive and Gram-negative, as well as strictly anaerobic bacteria. Recently community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as an etiological agent of FG with severe clinical course and even fulminant sepsis. Rarely FG may have a fungal etiology, being caused by yeast-like fungi Candida spp. or by moulds. Antibiotics should be administered parenterally and in doses high enough to reach an effective concentration in the infected tissues.

Molecular Characterization of Class 1, 2 and 3 Integrons in Serratia spp. Clinical Isolates in Poland - Isolation of a New Plasmid and Identification of a Gene for a Novel Fusion Protein.

PURPOSE: Gram-negative rods of the genus Serratia play an increasing role as etiological agents of healthcare-associated infections (HAI) in humans. These bacteria are characterized by natural and acquired resistance to several groups of antibacterial agents. The aim of the study was to characterize class 1, 2 and 3 integrons in the clinical isolates of Serratia spp. in Poland. METHODS: The study comprised 112 clinical strains of Serratia, isolated from patients hospitalized in Poland in 2010-2012. Identification of strains was confirmed using MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) system. Detection of class 1, 2 and 3 integrase DNA sequence was performed by multiplex-PCR. Amplicons obtained in the PCR reactions were purified and then sequenced bidirectionally. RESULTS: Among the analyzed strains, Serratia marcescens was a predominant species (103/112, 92.0%). All three classes of integrase DNA sequence were detected in the analyzed strains of Serratia spp. DNA sequence of class 3 integron, besides integrase gene, revealed three gene cassettes (dfrB3, bla GES-7,bla OXA/aac(6')-Ib-cr). BLAST analysis of DNA sequence revealed that class 3 integron was carried on 9448 bp plasmid which was named pPCMI3 - whole sequence of its DNA was submitted to GenBank NCBI (National Center for Biotechnology Information) - NCBI MH569711. CONCLUSION: In this study, we identified a new plasmid pPCMI3 harboring class 3 integron. This is the first report of a gene oxa/aac(6')-Ib-cr coding for a novel fusion protein, which consists of OXA ß-lactamase and acetyltransferase aac(6')-Ib-cr. In the analyzed strains, class 1 and 2 integrons were also detected. Among the strains with class 1 integron, nine contained cassette array 5'CS-aadA2-ORF-dfrA12-3'CS, and two - cassette array 5'CS-aacC1-ORF-ORF-aadA1-3'CS, which were not previously reported in Serratia spp.

The Effect of Lactobacillus salivarius SGL03 on Clinical and Microbiological Parameters in Periodontal Patients.

The destruction of periodontal tissues during periodontitis is the result of the immune-inflammatory reactions to the bacteria of dental biofilm. Probiotics may reduce dysbiosis by the modification of the dental microbiome, which can influence the immune-inflammatory mechanisms. The aim of this study was to estimate the clinical and microbiological parameters, before and after 30 days of application of the dietary supplement containing Lactobacillus salivarius SGL03 or placebo. The study was conducted in 51 patients with stage I or II periodontitis during the maintenance phase of treatment. The clinical parameters and the number of colony forming units (CFU) of bacteria in supragingival plaque were assessed before and after 30 days of the oral once daily administration of the dietary supplement in the form of suspension containing L. salivarius SGL03 or placebo. There were no changes in the PI scores between and within the groups. The value of BOP decreased in both groups. In the study group the significant reduction of the mean pocket depth was revealed (from 2.5 to 2.42, p = 0,027) but without the difference between the groups. There were no significant changes in the number of bacteria within the groups. In the control, but not the study group, positive correlations were observed between the clinical parameters (variables) and the number of bacteria. The use of the dietary supplement containing L. salivarius SGL03 may reduce pocket depth despite the lack of changes in other clinical parameters and the number of bacteria in supragingival plaque.

Bacterial infections in the early period after liver transplantation: etiological agents and their susceptibility.

BACKGROUND: The study comprises an analysis of bacterial infections in the early period after liver transplantation (LT) in adults. MATERIAL/METHODS: Eighty-three patients were followed for four weeks after LT. Samples comprised mainly blood, urine, surgical-site specimens, sputum, and stool. Culture and identification of the isolated microorganisms was done in accordance with standard microbiological procedures. Susceptibility testing was carried out using CLSI guidelines. Statistical analysis was done with Medi-Stat. RESULTS: In total, 913 samples from LT recipients were cultured. Of the 469 isolated strains, 331 (70.6%) were Gram-positive bacteria, 133 (28.4%) were Gram-negative bacteria, and 5 (1.0%) were yeast-like fungal strains. Of the 284 surgical-site isolates, 222 (78%) were Gram-positive and 61 (21.5%) were Gram-negative bacteria. Of the 99 blood culture isolates, 75 (75.8%) were Gram-positive and 22 (22.2%) of Gram-negative bacterial strains. Of the 73 urine samples, 46 (63.0%) were strains of Gram-negative, 25 (34.0%) of Gram-positive bacteria, and 2 (3.0%) fungal strains. In the 13 respiratory tract samples were 9 (69.0%) Gram-positive and 4 (31.0%) Gram-negative strains. In the 54 stool samples, 63.0% and 16.7% were C. difficile toxin- and culture-positive, respectively. In total, 138 strains of MRCNS, 10 of MRSA, 80 of HLAR, and 19 ESBL(+) were detected. CONCLUSIONS: The isolation of MDR bacterial strains such as MRSA (52.6%), MRCNS (81.7%), HLAR (86.0%), and ESBL(+) Gram-negative rods (12.5%) from patients after LT indicates the need for strict adherence to infection control procedures.

A clinical evaluation of efficacy of photodynamic therapy in treatment of reticular oral lichen planus: A case series.

Background The aim of the study was to clinically evaluate the efficacy of photodynamic therapy in treatment of reticular oral lichen planus (OLP). Methods Fifty patients aged 26-84, with 124 OLP lesions in total, underwent photodynamic therapy (PDT) mediated with topically applied 5% 5-aminolevulinic acid. ALA was activated by a custom-made diode lamp with a high-power LED emitting light at 630 nm and 300 mW delivered through an optical fiber probe. A light exposure dose was 150 J/cm2. The therapy comprised of 10 weekly illumination sessions. The lesions' response was macroscopically measured in millimeters with a periodontal probe and clinically evaluated at each session, then on completion of the series and throughout the 12-month follow-up. Results The baseline mean size of lesions was 3.99 cm2±3.73. The lesions on the buccal mucosa and lips (lining mucosa) were larger than those on the gingiva and tongue (masticatory mucosa) - 4.58 cm2±4.01 and 2.93 cm2±2.91 respectively. On completion of the therapy 109 sites improved, including 46 in complete remission. The mean reduction in size was 62.91% (p = 0.000000). 12-month after therapy mean reduction of the lesions was 78.7% (p = 0.000000), specifically 79.48% (p = 0.000000) within the lining mucosa and 76.11% on the masticatory mucosa. Conclusions The results proved that ALA-mediated photodynamic therapy with a 630 nm light was effective and as such it can be used as an optional treatment for symptomatic OLP.

New developments in vaccines against respiratory viruses.

Respiratory viruses are important human pathogens, affecting both healthy individuals and immunocompromised patients. In the past decade several new human respiratory viruses have been described, some of which have the potential to start an epidemic. At the same time, influenza A viruses continue to constitute a challenge to mankind as they undergo genetic modification. In this review new developments in the field of vaccines against respiratory viruses are presented, in view of the problems encountered during the development of such vaccines in the past, as well as the availability of modern technologies, which make it possible to create novel vaccines.

Biofilm production by clinical strains of Acinetobacter baumannii isolated from patients hospitalized in two tertiary care hospitals.

Microbial biofilms are considered as virulence factors. During the present study, 34 clinical strains of Acinetobacter baumannii, isolated from patients hospitalized in two tertiary care hospitals, were examined for biofilm formation. These strains showed high variability in biofilm formation. Furthermore, no relation could be found between the ability of biofilm production and molecular type, carbapenem resistance, site of isolation of the clinical strains of A. baumannii and disease severity. Interestingly, in two cases an increase in biofilm formation could be detected in A. baumannii isolates cultured from the same patient upon prolonged hospitalization.

Prevalence of bacteria and fungi in samples of cornea preservation fluid.

INTRODUCTION: Recipients of corneal transplants are at risk of healthcare-associated infections, which, apart from other causes of surgical site infections, may also occur as a result of the transfer of infected corneal tissue. In this study we assessed the risk of bacterial and fungal infections based on the results of routine microbiological testing of cornea preservation fluid samples. MATERIAL AND METHODS: We examined a total of 725 samples of corneal preservation fluid, obtained during a period of 3 years (2011-2013). Corneal preservation fluid samples were cultured and identified in accordance with standard microbiological methods. RESULTS: The analysis comprised 725 samples of corneal preservation fluid, of which 32 (4.4%) samples tested positively in microbiological cultures. In total, 34 strains of bacteria and fungi were cultured. Gram-positive bacteria, Gram-negative bacteria and fungi comprised 85.3%, 8.8% and 5.9% of these strains, respectively. Analysis of the susceptibility of the cultured bacterial isolates to gentamicin was also performed, as this antibiotic is present in the composition of corneal preservation fluid. Among the cultured bacterial strains, 10 (33.3%) were resistant to gentamicin. None of the 32 patients who received a cornea stored in preservation fluid contaminated with bacteria and/or fungi demonstrated infectious complications in the surgical site within 1 year following cornea transplantation. CONCLUSIONS: We postulate that perioperative antibiotic prophylaxis in cornea transplant recipients is important in preventing bacterial infections derived from the donor cornea. We believe that the addition of an antifungal agent to commercially available cornea preservation fluids should also be considered.