Aleksander Deptuła

Reduced expression of virulence factors in multidrug-resistant Pseudomonas aeruginosa strains

MDR Pseudomonas aeruginosa strains are isolated from clinical specimens with increasing frequency. It seems that acquiring genes which determine antibiotic resistance usually comes at a biological cost of impaired bacterial physiology. There is no information on investigations comparing phenotypic differences in MDR and MDS P. aeruginosa strains in literature. The study included 150 clinical P. aeruginosa isolates (75 classified as MDS and 75 as MDR). PFGE analysis revealed five pairs of identical isolates in the group of MDR strains and the results obtained for these strains were not included in the statistical analyses. MDR strains adhered to polystyrene to a lesser extent than MDS strains. The growth rate in the liquid medium was significantly lower for MDR strains. Detectable amounts of alginate were present in the culture supernatants of seven MDS and six MDR strains. The MDR P. aeruginosa strains which were investigated produced significantly lower amounts of extracellular material binding Congo Red, lower lipolytic, elastase, LasA protease, phospholipase C activity and pyocyanin quantity in culture supernatants when compared with MDS strains. No significant differences were observed between MDR and MDS strains in proteolytic activity. In conclusion, the MDR P. aeruginosa strains have impaired virulence when compared to MDS strains.

Risk factors for healthcare-associated infection in light of two years of experience with the ECDC point prevalence survey of healthcare-associated infection and antimicrobial use in Poland

BACKGROUND Healthcare-associated infection (HAI) and antimicrobial resistance are two of the most important threats in contemporary medicine. The aim of this study was to evaluate independent risk factors associated with higher prevalence of HAI in a population of patients hospitalized in acute care hospitals in Poland. METHODS This study was conducted in accordance with the protocol of the European Centre for Disease Prevention and Control (ECDC) point prevalence survey of HAI and antimicrobial use. Data for 16,598 patients were collected from 50 hospitals. Independent risk factors assessed included: hospital size and type; consumption of alcohol hand rub; isolation capacity; number of beds per full-time-equivalent (FTE) infection control doctor/nurse; sex; age; hospitalization specialty; exposure to invasive procedures; and McCabe score. FINDINGS The highest prevalence of HAI was observed in large and teaching hospitals (6.7% and 7.4%, respectively), in children aged less than one (13.3%) and among males (7.2%). With regard to invasive procedures, the strongest association was observed for central venous catheterization (30.2%), intubation (41.6%) and urinary catheterization (17.5%). The highest prevalence of HAI was observed among patients in intensive care units (adult 39.8%, paediatric 30.8%). The lowest prevalence of HAI was observed in hospitals with one FTE infection control nurse per <200 beds (4.1%). CONCLUSION A high prevalence of HAI combined with high exposure to risk factors among patients in paediatric and adult ICUs should result in the introduction of an HAI prevention programme across Poland.

Impact of fructose diet and renal failure on the function of pancreatic islets.

Objectives This study was designed to evaluate the impact of fructose-rich diet and chronic kidney disease (CKD) on the in vitro function of pancreatic islets. Methods Fifty-four rats were divided into 3 equal groups as follows: control, rats with CKD 1/2 that underwent surgical uninephrectomy, and rats with CKD 5/6 that underwent uninephrectomy and kidney cortex mass resection. Each group was further assigned to 3 diet protocols—regular diet, regular diet with 10% fructose (F10), and 60% fructose-rich diet (F60). After 8 weeks of insulin administration, C-peptide, glycated hemoglobin level, serum urea nitrogen, creatinine clearance, and homeostasis model assessment of insulin resistance were evaluated. Static glucose insulin stimulation test of isolated pancreatic islets and histologic analysis of pancreatic tissue were performed. Results The F10 diet increased the levels of insulin and C-peptide in all groups. Homeostasis model assessment of insulin resistance was increased in all animals fed with fructose. The elevated levels of creatinine and diminished creatinine clearance were detected in CKD 5/6 rats fed with 60% fructose-rich diet. The F10 diet resulted in high levels of serum insulin and C-peptide and glucose-stimulated insulin secretion. Fructose-rich diet increased the islet size and number, with irregular morphology and exocrine tissue fibrosis. Conclusions The fructose-rich diet accelerates the progression of CKD and affects the pancreatic islet function.

Prevalence of healthcare-associated infections in Polish adult intensive care units: summary data from the ECDC European Point Prevalence Survey of Hospital-associated Infections and Antimicrobial Use in Poland 2012–2014

BACKGROUND Infection is a major cause of morbidity and mortality in intensive care units (ICUs) worldwide. Local epidemiological studies need to be conducted to set the priorities for surveillance and prevention programmes. AIM To investigate the epidemiology of hospital-acquired infections (HAIs) among patients admitted to Polish adult ICUs over a three-year period. METHODS Data were collected according to the European Centre for Disease Prevention and Control (ECDC) European Union Point Prevalence Survey of Healthcare-associated Infections and Antimicrobial Use in European Acute Care Hospitals (EU-PPS HAI & AU) protocol for 39,318 patients within 160 acute care hospitals. From this initial database, data for adult ICU patients (N=945) were filtered for further analyses. FINDINGS HAIs were present in 370 patients (39%) and 430 HAI episodes were recorded. The most common HAIs were respiratory tract infections (45%), usually caused by Enterobacteriaceae and Gram-negative non-fermenters. The majority (87%) of these infections were likely to be device associated. Out of 61 cases of bloodstream infection, 51% were catheter associated. These bloodstream infections were mainly caused by coagulase-negative staphylococci. Among 57 cases of surgical site infection, 42% were classified as organ/space, 33% were classified as deep incisional, and 25% were classified as superficial. The predominant micro-organisms were Enterobacteriaceae and Staphylococcus aureus. Out of 50 cases of urinary tract infection, 96% were device associated. CONCLUSIONS The prevalence of HAI among Polish adult ICU patients is higher than described in similar studies, but may be partially affected by methodological differences. The proportion of device-associated infections was very high, so there is an urgent need to introduce countrywide, targeted surveillance and prevention programmes.

Transdifferentiation of Bone Marrow Mesenchymal Stem Cells into the Islet-Like Cells: the Role of Extracellular Matrix Proteins

Pancreatic islet implantation has been recently shown to be an efficient method of treatment for type 1 diabetes. However, limited availability of donor islets reduces its use. Bone morrow would provide potentially unlimited source of stem cells for generation of insulin-producing cells. This study was performed to evaluate the influence of extracellular matrix proteins like collagen, laminin, and vitronectin on bone marrow mesenchymal stem cells (BM-MSCs) transdifferentiation into islet-like cells (ILCs) in vitro. To our knowledge, this is the first report evaluating the importance of vitronectin in transdifferentiation of BM-MSCs into ILCs. Rat BM-MSCs were induced to ILCs using four-step protocol on plates coated with collagen type IV, laminin type I and vitronectin type I. Quantitative real-time PCR was performed to detect gene expression related to pancreatic β cell development. The induced cells expressed islet-related genes including: neurogenin 3, neurogenic differentiation 1, paired box 4, NK homeobox factor 6.1, glucagon, insulin 1 and insulin 2. Laminin but not collagen type IV or vitronectin enhanced expression of insulin and promoted formation of islet-like structures in monolayer culture. Laminin triggered transdifferentiation of BM-MSCs into ILCs.

Surveillance of Antibiotic Prescribing in Intensive Care Units in Poland

Antibiotic use and microbial resistance in health care-associated infections are increasing globally and causing health care problems. Intensive Care Units (ICUs) represent the heaviest antibiotic burden within hospitals, and sepsis is the second noncardiac cause of mortality in ICUs. Optimizing appropriate antibiotic treatment in the management of the critically ill in ICUs became a major challenge for intensivists. We performed a surveillance study on the antibiotic consumption in 108 Polish ICUs. We determined which classes of antibiotics were most commonly consumed and whether they affected the length of ICU stay and the size and category of the hospital. A total of 292.389 defined daily doses (DDD) and 192.167 patient-days (pd) were identified. Antibiotic consumption ranged from 620 to 3960 DDD/1000 pd. The main antibiotic classes accounted for 59.6% of the total antibiotic consumption and included carbapenems (17.8%), quinolones (14%), cephalosporins (13.7%), penicillins (11.9%), and macrolides (2.2%), respectively, whereas the other antibiotic classes accounted for the remainder (40.4%) and included antifungals (34%), imidazoles (20%), aminoglycosides (18%), glycopeptides (15%), and polymyxins (6%). The most consumed antibiotic classes in Polish ICUs were carbapenems, quinolones, and cephalosporins, respectively. There was no correlation between antibiotic consumption in DDD/1000 patient-days, mean length of ICU stay, size of the hospital, size of the ICU, or the total amount of patient-days. It is crucial that surveillance systems are in place to guide empiric antibiotic treatment and to estimate the burden of resistance. Appropriate use of antibiotics in the ICU should be an important public health care issue.

The Prevalence of Exoenzyme S Gene in Multidrug-Sensitive and Multidrug-Resistant Pseudomonas aeruginosa Clinical Strains

Pseudomonas aeruginosa rods are one of the most commonly isolated microorganisms from clinical specimens, usually responsible for nosocomial infections. Antibiotic-resistant P. aeruginosa strains may present reduced expression of virulence factors. This fact may be caused by appropriate genome management to adapt to changing conditions of the hospital environment. Virulence factors genes may be replaced by those crucial to survive, like antimicrobial resistance genes. The aim of this study was to evaluate, using PCR, the occurrence of exoenzyme S-coding gene (exoS) in two distinct groups of P. aeruginosa strains: 83 multidrug-sensitive (MDS) and 65 multidrug-resistant (MDR) isolates. ExoS gene was noted in 72 (48.7%) of the examined strains: 44 (53.0%) MDS and 28 (43.1%) MDR. The observed differences were not statistically significant (p = 0.1505). P. aeruginosa strains virulence is rather determined by the expression regulation of the possessed genes than the difference in genes frequency amongst strains with different antimicrobial susceptibility patterns.

Selected aspects of epidemiological surveillance in the intensive care unit of the Centre of Pulmonology and Thoracic Surgery in Bystra

Sir, Intensive care units (ICU) have been witnessing increasing antibiotic resistance and its related problems. The large consumption of antibiotics facilitates the selection of resistant bacterial strains which, in turn, make rational choices of empirical antibiotic courses much more difficult and treatment outcomes much more uncertain. Indeed, such departments are even perceived as “epicentres” of nosocomial infections, with the particular selection of multiresistant microorganism strains [1, 2]. Efficient epidemiological surveillance permits early identification and facilitates problem solving in the ICU and which must not be underestimated in the era of globally increasing antibiotic resistance. A five-bed intensive care unit at the Centre of Pulmonology and Thoracic Surgery was created in 2014, and in July of the same year was awarded a contract with the Polish National Health Fund. The unit participates in the programme of active infection surveillance lead by the Polish Society of Nosocomial Infections, as well as in the PPS programme under the National Programme for the Protection of Antibiotics. Moreover, a pilot study of the standardized versions of active infection surveillance is being carried out at the unit according to the guidelines issued by the European Centre for Disease Control and Prevention (ECDC). Participation in the above-mentioned programs facilitated the gathering of the epidemiological data presented herein. One hundred and nine patients, aged 21–92 years (mean age of 63.5 years), were hospitalized at the unit during its first year in service, and comprised 67.9% men. The mean APACHE II score was 18.5, and median score 18. On admission, 62 patients (59%) had signs of infection. Twentyeight patients (25.7%) were admitted due to perioperative complications after thoraco-surgical procedures. The mean duration of patient hospitalization at the ICU was 12.7 days, while the mortality rate was 17.4% (19 patients). The mean ICU bed occupation rate was 76%. The calculated “density” of most common invasive procedures was the following: artificial ventilation, 52.7/100 patient-days; central vein catheterization, 84.85/100 patient-days; arterial cannulation, 66.7/100 patient-days; bladder catheterization, 87.2/100 patient-days; and body cavity drainage, 15.4/100 patient-days. During the analysed period, 1,092 microbiological analyses were performed (218 tests/bed/year, mean of 10 tests/patient). The usage of hand disinfectants varied over time between 129 and 297 mL person day-1 (mean of 208.3 mL person-day-1), which gives 69 episodes of hand disinfection per day during the care of a single patient. Nosocomial infections at this ICU are registered according to the ECDC criteria [3]. During the analysed period, 38 nosocomial infections were registered (2.75/100 patientdays) in a total of 31 patients (28.4% of all hospitalizations). Patients with diagnosed nosocomial infection had had a significantly higher APACHE II score on admission (21 vs. 17.7 points; P = 0.03); no differences were observed as to patient age or sex. Although hospitalizations in patients with diagnosed nosocomial infections were significantly longer than in other subjects (23 vs. 8.6 days), no significant difference in mortality was observed between the groups. Bloodstream infections (BSI) as a cause of nosocomial disease involved 7.9/1,000 patient-days. When considering cases compatible with the laboratory definition of vascular catheter-related bacteraemia [4], the prevalence ratio was 2.6/1,000 patient-days of catheter usage. Respiratory tract infections occurred at the rate of 26.1/1,000 days of artificial ventilation. The respective rate of urinary tract infections was 2.5/1,000 days with a bladder catheter. Colonisation with alarm pathogens on admission to the ICU was detected in 28 patients (25.7%). These patients had higher APACHE II scores on admission (21.3 vs. 17.7; P = 0.02), more often acquired nosocomial infections during hospitalisation in the ICU (35.7 vs. 25.9%; P = 0.3), while the mortality rate was higher in this group (32.1 vs.12.3%; P = 0.01). Antibiotics were administered in 83 patients (76.1%). The monthly consumption of antibiotics was in a range of between 80.18 and 257 DDD/100 patient-days of hospitalisation (mean of 135.6 DDD/100 patient-days). The greatest consumption rates involved fluoroquinolones (17.7%), colistin (12.3%), third generation cephalosporins (12.1%), carbapenems (11.6% ), and penicillins with beta-lactamase inhibitors (10%). Patients receiving antibiotics demonstrated a higher mortality rate (21.7 vs. 3.8%; P = 0.03), were hospitalised for longer periods (mean hospitalization of 14.3 vs. 7.3 days; P = 0.005), and more often experienced colonisation by alert pathogens (51.2 vs. 20%; P = 0.18). Anestezjologia Intensywna Terapia 2016, tom 48, numer 4, 287–288 ISSN 0209–1712 www.ait.viamedica.pl