Analysis of pathogens and antimicrobial treatment in different groups of patients with chronic otitis media.

OBJECTIVE: Microbial infection plays an important role in exacerbation of chronic otitis media. The aim of this study was to analyse the microbiota in chronic otitis media in the context of local treatment. METHOD: In this prospective study, samples for microbiological examination were taken from 119 patients who underwent operation because of chronic otitis media. RESULTS: The results were compared between groups depending on the type of operation (none, tympanoplasty or radical), the presence of cholesteatoma or granulomatous tissue or discharge from the ear as a symptom of exacerbation. Antibiotic susceptibility of germs was analysed to define the strategy of treatment. A total of 209 samples were collected from 119 patients with chronic otitis media. CONCLUSION: Pseudomonas aeruginosa and Staphylococcus aureus were pathogens most frequently identified from the ear in the course of chronic otitis media. Pseudomonas aeruginosa was concerned with major pathology of the middle ear (radical surgery, cholesteatoma or granulomatous tissue, persisting discharge after treatment), whereas Staphylococcus aureus was obtained in dry perforations without other pathology in the middle-ear cavity. Ciprofloxacin was effective against Staphylococcus aureus, but Pseudomonas aeruginosa strains were ciprofloxacin resistant.

Antimicrobial effect of radiant catalytic ionization.

The main purpose of micro-organisms elimination from the air and surfaces is to ensure microbiological safety in health care facilities or food production plants. Currently, many disinfection methods are used, both physical, chemical and, increasingly, biological. Scientists seek new solutions with high antimicrobial effectiveness (especially against the drug-resistant strains of bacteria), low production and operating costs, and, above all, the safety of patients and food consumers. The limitation of the methods used so far is primarily the micro-organisms acquire the resistance, mainly to antimicrobial agents. One of the new and alternative methods of disinfection is radiant catalytic ionization (RCI). RCI is an active method of air and surface purification. The technology proved high efficiency against viruses, Gram-positive and -negative bacteria, and fungi, both in the air and on surfaces (planktonic forms and biofilm). RCI has many advantages as well as some minor limitations. This overview summarizes the current knowledge about RCI technology.

Application of the appropriate molecular biology-based method significantly increases the sensitivity of group B streptococcus detection results.

BACKGROUND: Streptococcus agalactiae (group B streptococcus: GBS) is a leading cause of early- and late-onset diseases in neonates. Reliable results of GBS carriage investigation among pregnant women may decrease the incidence of neonatal infection and mortality. AIM: To compare the results of conventional culture investigation with those of the US Food and Drug Administration-approved nucleic acid amplification test (BD Max GBS (Becton Dickinson)), and to establish our own protocols of standard polymerase chain reaction (PCR). METHODS: A total of 250 vaginal-rectal swabs from three different hospitals in Bydgoszcz, Poland, were used to evaluate GBS carriage. Standard laboratory technique (overnight culture in broth enrichment media) results were compared with those of BD Max GBS assay (Becton Dickinson) and two standard PCR protocols, established to detect the cfb and 16S rRNA S. agalactiae genes, from the overnight cultures of the samples in the liquid enrichment media. FINDINGS: The overall GBS carriage was estimated as 16.4-23.2%, depending on the applied detection method. The highest percentage of positive results, from each lab-oratory was obtained with the application of BD Max GBS assay. The differences in the number of positive results obtained with this particular method were statistically significant. Overall, 27 discrepancies were noted for the results obtained with the application of the methods compared. CONCLUSIONS: The methods applied for GBS detection differ in sensitivity. A culture technique, though very specific, appears to be less sensitive at detecting S. agalactiae compared with the commercially available BD Max GBS assay or in-house PCR protocols established for this purpose.

Assessment of endoscope cleaning and disinfection efficacy, and the impact of endoscope storage on the microbiological safety level.

AIMS: The aim of the study was microbiological evaluation of the efficacy of cleaning and disinfection of endoscopes carried out with the use of endoscope washer-disinfector EndoCleaner and evaluation of the endoscope storage cabinet providing a controlled environment. METHODS AND RESULTS: The efficacy evaluation of endoscope cleaning and disinfection using the endoscope washer-disinfector EndoClener (AORT) was carried out in accordance with the PN-EN ISO 15883 standard, and the validity of endoscope storage cabinet (TRIBO LLC) was evaluated in accordance with the PN-EN 16442 standard. The micro-organism tested used in the study were as follows: Pseudomonas aeruginosa ATCC® 15442™, Enterococcus faecium ATCC® 12952™, Clostridium sporogenes ATCC® 19404™ (spores), Candida albicans ATCC® 90028™ and Aspergillus brasiliensis DSM® 1988™ (surrogate for Asperigllus niger ATCC® 16404™). It was demonstrated that the endoscope reprocessing carried out in the washer-disinfector EndoCleaner guaranteed the elimination of the micro-organism tested, and the tested endoscope storage cabinet met the microbiological criteria defined by the Polish standard PN-EN 16442 in the scope of tests. CONCLUSION: The obtained results showed that usage of washer-disinfector EndoCleaner and endoscope storage cabinet ensures the microbiological safety of using endoscopes. SIGNIFICANCE AND IMPACT OF STUDY: The increase in the frequency of procedures applying endoscopes contributes to the increased risk of transmission of potentially pathogenic micro-organisms remaining after insufficient cleaning and disinfection of these devices. Research allows assessing the effectiveness of antimicrobial cleaning and disinfection of endoscopes and the safety of storing this equipment in an endoscope cabinet. A particularly innovative aspect is equipping the cabinet with a module generating the phenomenon of radiant catalytic ionization, which is a unique solution on the market. This is one of the very few works involving the assessment of each stage, that is contamination, washing and disinfection, drying and storage of endoscopes.

Elimination of Klebsiella pneumoniae NDM from the air and selected surfaces in hospital using radiant catalytic ionization.

Due to increasing antibiotic resistance Klebsiella pneumoniae is a serious threat for the hospitalized patients. The aim of this study was the assessment of radiant catalytic ionization (RCI) efficacy on K. pneumoniae reduction in the air and on selected surfaces. Four K. pneumoniae NDM and ESBLs-producing strains were included in the study. Three types of surface were tested: cotton-polyester, terry and PVC. It was found that RCI significantly reduced the number of bacteria from all types of surface (terry: 0·56-1·22 log CFU m2 , cotton-polyester: 2·15-3·71 log CFU per m2 , PVC: 4·45-4·92 log CFU per m2 ) as well as from the air (1·80 log CFU per m3 ). The RCI technology may be a useful disinfection method in hospitals. SIGNIFICANCE AND IMPACT OF THE STUDY: Microbial contamination of air and surfaces in hospitals play an important role in healthcare-associated infections. The aim was the assessment of Klebsiella pneumoniae elimination using radiant catalytic ionization (RCI). K. pneumoniae are aetiological agent of nosocomial infections, such as: pneumonia, infections of urinary tract, blood, e.t.c. The strains producing the New Delhi metallo-ß-lactamases are one of the greatest epidemiological threat. The use of RCI eliminate the tested bacteria from the hospital environment, but can also be effective in food processing plants or public facilities, ensuring the safety of people and products. This research is scarce in references and has a large innovation and application potential.

VIM/IMP carbapenemase-producing Enterobacteriaceae in Poland: epidemic Enterobacter hormaechei and Klebsiella oxytoca lineages.

Objectives: To analyse VIM/IMP-type MBL-producing Enterobacteriaceae isolates identified in Poland during 2006-12. Methods: Isolates were typed by PFGE, followed by MLST. blaVIM/IMP genes were amplified and sequenced within class 1 integrons. Their plasmidic versus chromosomal location was assessed by nuclease S1 and I-CeuI plus hybridization experiments. Plasmids were characterized by transfer assays and PCR-based replicon typing. Results: One hundred and nineteen VIM/IMP-positive Enterobacteriaceae cases were reported in Poland from the first case in 2006 until 2012. The patients were in 54 hospitals and were infected or colonized by 121 organisms, including Enterobacter cloacae complex (n = 64), Klebsiella oxytoca (n = 23), Serratia marcescens (n = 20) and Klebsiella pneumoniae (n = 11). The isolates represented numerous pulsotypes and mainly original STs, and carried eight integrons with blaVIM-1-like genes (blaVIM-1/-4/-28/-37/-40; n = 101), three with blaVIM-2 variants (blaVIM-2/-20; n = 17) and one with blaIMP-19 (n = 3). Six integrons were new, and five and two formed prevalent families of In238-like (n = 96) and In1008-like (n = 16) elements, respectively. In238 (aacA4-blaVIM-4rpt) and In1008 (blaVIM-2-aacA4) had been originally observed in Polish Pseudomonas aeruginosa, suggestive of their transfer to enterobacteria, followed by spread and diversification. Four organisms have disseminated inter-regionally, i.e. Enterobacter hormaechei ST90 with plasmidic In238/In238a integrons (n = 36), K. oxytoca ST145 with a chromosomal In237-like element (n = 18) and two subclones of E. hormaechei ST89 with In1008- or In238-type variants (n = 8 and n = 7, respectively). Conclusions: The epidemiology of VIM/IMP-producing Enterobacteriaceae in Poland has revealed a remarkable number of specific or novel characteristics of the organisms, with some possible links to other mid-southern European countries.

Effect of electron beam and gamma radiation on drug-susceptible and drug-resistant Listeria monocytogenes strains in salmon under different temperature.

AIMS: To investigate the effect of gamma radiation and high energy electron beam doses on the inactivation of antibiotic-susceptible and antibiotic-resistant Listeria monocytogenes strains inoculated on the surface of raw salmon fillets stored at different temperature (-20, 4 and 25°C). METHODS AND RESULTS: The population of bacteria strains resistance to penicillin, ampicillin, meropenem, erythromycin and trimethoprim-sulfamethoxazole was generated. When using gamma irradiation, the theoretical lethal dose ranged from 1·44 to 5·68 kGy and for electron beam the values ranged from 2·99 to 6·83 kGy. The theoretical lethal dose for both radiation methods was higher for antibiotic-resistant strains. Gamma radiation proved to be a more effective method for extending salmon fillet shelf-life. The evaluation of pulsed-field gel electrophoresis electrophoregram revealed that the repair of radiation-caused DNA damage occurred faster in antibiotic-resistant L. monocytogenes strains. The number of live L. monocytogenes cells, 40 h after irradiation, also was higher in antibiotic-resistant strain suspension. CONCLUSIONS: The present study showed that gamma radiation was more effective in the elimination of the tested micro-organisms and food preservation, than a high energy electron beam. The antibiotic-resistant L. monocytogenes strains were more resistant to both radiation methods. SIGNIFICANCE AND IMPACT OF THE STUDY: There are a lot of research on the effect of radiation on the number of bacteria in food products. However, there is almost no information about the effect of strain properties, such as drug susceptibility, virulence, etc., on their resistance to ionizing radiation. An increasing number of drug resistant bacterial strains isolated from food, encourages to take up this research subject.

The effectiveness of radiant catalytic ionization in inactivation of Listeria monocytogenes planktonic and biofilm cells from food and food contact surfaces as a method of food preservation.

AIMS: The aim of the study was to evaluate the microbicidal effectiveness of radiant catalytic ionization (RCI) against Listeria monocytogenes strains in the form of planktonic cells and biofilm on food products and food contact surfaces as a method of food preservation. METHODS AND RESULTS: The study material comprised six strains of L. monocytogenes, isolated from food. Samples of different types of food available by retail (raw carrot, frozen salmon filets, soft cheese) and the fragments of surfaces (stainless steel AISI 304, rubber, milled rock tiles, polypropylene) were used in the experiment. The obtained results showed the effectiveness of RCI in the inactivation of both forms of the tested L. monocytogenes strains on all the surfaces. The effectiveness of RCI for biofilm forms was lower as compared with planktonic forms. The PRR value ranged from 18·19 to 99·97% for planktonic form and from 3·92 to 70·10% for biofilm. CONCLUSIONS: The RCI phenomenon induces the inactivation of L. monocytogenes on surfaces of food and materials used in the processing industry to a varying degree, depending on the manner of surface contamination, the properties of the contaminated materials as well as on the origin of the strain and the properties of surrounding dispersive environment in which the micro-organisms were suspended. SIGNIFICANCE AND IMPACT OF THE STUDY: Searching of new actions aimed at the reduction of the microbial contamination of food and food contact surfaces are extremely important. RCI method has been already described as an effective technique of microbial and abiotic pollution removal from air. However, our studies provide new, additional data related to evaluation the RCI efficacy against microbes on different surfaces, both in planktonic and biofilm form.