Antibiotic consumption in laboratory confirmed vs. non-confirmed bloodstream infections among very low birth weight neonates in Poland.

BACKGROUND: Newborns are a population in which antibiotic consumption is extremely high. Targeted antibiotic therapy should help to reduce antibiotics consumption. The aim of this study was an assessment of antibiotic usage in bloodstream infections treatment in the Polish Neonatology Surveillance Network (PNSN) and determining the possibility of applying this kind of data in infection control, especially for the evaluation of standard methods of microbiological diagnostics. METHODS: Data were collected between 01.01.2009 and 31.12.2013 in five teaching NICUs from the PNSN. The duration of treatment in days (DOT) and the defined daily doses (DDD) were used for the assessment of antibiotics consumption. RESULTS: The median DOT for a single case of BSI amounted to 8.0 days; whereas the median consumption expressed in DDD was 0.130. In the case of laboratory confirmed BSI, median DOT was 8 days, and consumption-0.120 DDD. Median length of therapy was shorter for unconfirmed cases: 7 days, while the consumption of antibiotics was higher-0.140 DDD (p < 0.0001). High consumption of glycopeptides expressed in DOTs was observed in studied population, taking into account etiology of infection. CONCLUSIONS: Even application of classical methods of microbiological diagnostics significantly reduces the consumption of antibiotics expressed by DDD. However, the high consumption of glycopeptides indicates the necessity of applying rapid diagnostic assays. Nevertheless, the assessment of antibiotic consumption in neonatal units represents a methodological challenge and requires the use of different measurement tools.

Comprehensive detection and identification of bacterial DNA in the blood of patients with sepsis and healthy volunteers using next-generation sequencing method - the observation of DNAemia.

Blood is considered to be a sterile microenvironment, in which bacteria appear only periodically. Previously used methods allowed only for the detection of either viable bacteria with low sensitivity or selected species of bacteria. The Next-Generation Sequencing method (NGS) enables the identification of all bacteria in the sample with their taxonomic classification. We used NGS for the analysis of blood samples from healthy volunteers (n = 23) and patients with sepsis (n = 62) to check whether any bacterial DNA exists in the blood of healthy people and to identify bacterial taxonomic profile in the blood of septic patients. The presence of bacterial DNA was found both in septic and healthy subjects; however, bacterial diversity was significantly different (P = 0.002) between the studied groups. Among healthy volunteers, a significant predominance of anaerobic bacteria (76.2 %), of which most were bacteria of the order Bifidobacteriales (73.0 %), was observed. In sepsis, the majority of detected taxa belonged to aerobic or microaerophilic microorganisms (75.1 %). The most striking difference was seen in the case of Actinobacteria phyla, the abundance of which was decreased in sepsis (P < 0.001) and Proteobacteria phyla which was decreased in the healthy volunteers (P < 0.001). Our research shows that bacterial DNA can be detected in the blood of healthy people and that its taxonomic composition is different from the one seen in septic patients. Detection of bacterial DNA in the blood of healthy people may suggest that bacteria continuously translocate into the blood, but not always cause sepsis; this observation can be called DNAemia.

Urinary tract infections caused by Pseudomonas aeruginosa among children in Southern Poland: Virulence factors and antibiotic resistance.

OBJECTIVE: The aim of this study was to analyze antibiotic resistance and virulence patterns in Pseudomonas aeruginosa (PAR) isolates from urinary tract infections among children in Southern Poland. MATERIALS AND METHODS: This study comprised consecutive, non-repetitive PAR isolates sent from two collaborative laboratories. The study group consisted of children aged up to 17 years from Southern Poland with culture-proven PAR UTIs. Relevant information about patients with UTIs, such as age, sex, and type of infection (polymicrobial or monomicrobial), was collected. Isolates were screened for major virulence factors found in uropathogenic PAR strains. Multidrug-resistant (MDR) strains were defined as strains not susceptible to one antimicrobial in at least three different antimicrobial classes. Extensively drug resistant (XDR) strains were defined as strains susceptible to no more than two antimicrobial classes. RESULTS: The total prevalence of PAR UTIs was 2.1%, and in children <5 years of age it was 3.0%. A total of 26 isolates was tested: 21 from outpatients and five from inpatients. Most infections (80.8%) occurred in children ≤ 4 years of age. The most prevalent virulence gene was exoY (96.2%). The prevalence of other effector proteins was 88.5% for exoT, 92.3% for exoS, and 19.2% for exoU. The gene for LasB was present in 80.8% of isolates; the gene for AprA in 61.5%; the gene for PilA in 19.2%; and the gene for PilB was not detected. The PAR isolates were generally susceptible to beta-lactam and aminoglycoside antimicrobials. All isolates were also susceptible to colistin. A large proportion of isolates were resistant to carbapenems and fluoroquinolones (Fig. 1). No significant differences were found in antimicrobial resistance between males and females or inpatients and outpatients (p > 0.05 for all tested antimicrobials), or in antimicrobial resistance between younger (≤ 5 years old, n = 21) and older (> 5 years old, n = 5) children (p > 0.05 for all tested antimicrobials). Two isolates were classified as XDR and none as MDR. The EDTA test yielded one MBL-positive isolate (3.8%), from a 17-year-old patient in home care. No isolates with genes for the KPC, IMP, or VIM were identified. CONCLUSION: As data on UTIs in children with Pseudomonas etiology are scarce, this paper provides useful information for clinicians and allows for comparison between Poland and other countries. Our findings have important implications for clinicians treating UTIs empirically, because the success of empiric treatment is based on knowledge of pathogen antimicrobial susceptibility patterns.

Infections and risk-adjusted length of stay and hospital mortality in Polish Neonatology Intensive Care Units.

BACKGROUND: The objectives of this study were to analyze the impact of infections on prolonging hospital stay with consideration of underlying risk factors and determining the mortality rates and its association with infections. METHODS: An electronic database developed from a continuous prospective targeted infection surveillance program was used in the study. Data were collected from 2009 to 2012 in five Polish tertiary academic neonatal intensive care units (NICUs). The length of stay (LOS) of 2,003 very low birth weight (VLBW) neonates was calculated as the sum of the number of days since birth until death or until reaching a weight of 1,800g. RESULTS: The median LOS for neonates with infections was twice as high as for neonates without infection. LOS was significantly affected by the overall general condition of the neonate, as expressed by both gestational age and birth weight as well as by the Clinical Risk Index for Babies (CRIB) score; another independent factor was presence of at least one infection. Risk of in-hospital mortality was significantly increased by male sex and vaginal birth and was lower among breastfed neonates. Deaths were significantly more frequent in neonates without infection. CONCLUSIONS: The general condition of VLBW infants statistically increase both their risk of mortality and LOS; this is in contrast to the presence of infection, which significantly prolonged LOS only.

Control of an outbreak of Acinetobacter baumannii infections using vaporized hydrogen peroxide.

BACKGROUND: Multidrug-resistant Acinetobacter baumannii (MRAB) is a serious nosocomial pathogen characterized by its survival on inanimate surfaces for long periods, making control of outbreaks difficult. AIM: To analyse two hospital outbreaks caused by MRAB, determine their epidemiology, carbapenem-resistance mechanisms and assess the effectiveness of surface disinfection by vaporized hydrogen peroxide (VHP). METHODS: MRAB strains were isolated from patients in two intensive care units (ICUs). Antimicrobial susceptibility testing was performed by E-test. Polymerase chain reaction (PCR) was used to detect the presence of the most common A. baumannii carbapenemases. Epidemiological typing was performed by rep-PCR (DiversiLab) and pulsed-field gel electrophoresis. VHP was used to decontaminate the affected ICUs. FINDINGS: MRAB was isolated from 28 patients between January 2009 and September 2010. All isolates were resistant to ciprofloxacin and gentamicin. Twenty-one were also resistant to carbapenems. Carbapenem resistance was associated primarily with the acquired OXA-23-like enzyme. Genotyping revealed three clones; the predominant clone corresponded to the international clone (IC) 2. Typing of the isolates pointed to a multifocal outbreak without a single source of infection, with horizontal spread of the dominating clone among ICU patients. A combination of rigorous infection control measures including strict isolation, education of staff, hand hygiene and surface decontamination using VHP halted the outbreak. CONCLUSION: The results of this study confirm the importance of rigorous infection prevention and control measures, combined with VHP decontamination in controlling an outbreak of MRAB.

Comparison of SSI rates in endoarthroplasty of hip and knee in a Cracow patient population and the importance of postdischarge surveillance.

BACKGROUND: The aim of the study was to analyse the epidemiological and microbiological analysis of surgical site infections in patients that underwent knee or hip endoarthroplasty procedures. MATERIALS AND METHODS: The epidemiological and microbiological surveillance was carried out by the local infection control team in cooperation with the Department of Bacteriology, at the Chair of Microbiology, Jagiellonian University Medical College in Cracow. RESULTS: A total of 651 patients operated in the Department of Orthopedics, Trauma Surgery and Rehabilitation of Cracow Rehabilitation Center in Poland were analyzed. Twenty-three cases of SSI were detected. The cumulative incidence after hip prosthesis (HPRO) procedures was 2.3%, while for knee prosthesis (KPRO) it was 7.0. Standardized risk index, comparing the incidence in our study to German hospitals, shows a statistically significant, higher incidence in patients with knee replacement procedures in our study (p=0.004). Among etiological agents of SSIs, we demonstrated the dominating role of Gram-positive cocci to be 75% (30% methicillin resistant). This resistance was confirmed only in case of coagulasenegative staphylococci (no MRSA were cultured). Gramnegative rods were isolated with a frequency of 25%: 41.6% in SSI after hip endoarthroplasty and 15% after knee endoarthroplasty. Postdischarge surveillance encompassed 59% of operated patients. CONCLUSION: The incidence of SSIs of hip prosthesis in our study was comparable to the incidence in the German KISS program, where surveillance is integrating a highly sensitive postdischarge detection. On the other hand, we observed a higher, statistically significant cumulative incidence in case of knee endoarthroplasty. Our microbiological data show effective control of methicillin-resistant Staphylococcus aureus and are also in agreement with the data found in literature referring to coagulasenegative multi-resistant staphylococci as an important problem in the orthopaedic surgery of the knee joint.

Acute appendicitis: the role of enterotoxigenic strains of Bacteroides fragilis and Clostridium difficile.

BACKGROUND: The aim of this study was to investigate whether there is a relationship between enterotoxin-producing B. fragilis strains and toxigenic C. difficile strains and the pathogenesis of acute appendicitis. MATERIAL AND METHODS: Post-appendectomy tissues from 34 patients with histopathologically confirmed phlegmonous or gangrenous appendicitis were studied. RESULTS: Among 86 anaerobes isolated, the B. fragilis group was most frequently isolated: 34 B. fragilis strains were cultured from 21 post-appendectomy tissues. Two enterotoxin-producing B. fragilis strains were found. Enterotoxin titers (1:10 and 1:160, respectively) were measured on HT29/C cells. The presence of the enterotoxin gene was confirmed by PCR in DNA extracted from both strains. Among 21 DNA samples isolated from those post-appendectomy tissues from which B. fragilis strains were cultured, the presence of the enterotoxin gene was confirmed in only one case (the corresponding B. fragilis strain enterotoxin titer was 1:160). A unique toxigenic C. difficile strain was also cultured from the tissue of an adult patient with gangrenous non-perforated appendicitis. The presence of toxin A and toxin B genes was confirmed by PCR in DNA extracted from the C. difficile strain, but these genes were not found in the DNA extracted from the corresponding tissue. CONCLUSION: The presence of enterotoxigenic B. fragilis and toxigenic C. difficile strains was shown in post-appendectomy tissue from patients with phlegmonous and gangrenous appendicitis, and the B. fragilis enterotoxin gene was detected directly in the corresponding tissue. Further investigations (including immunologic aspects) require to confirm the role of these toxins in pathogenesis of acute appendicitis.

In vitro antibiotic susceptibility of Bacteroides fragilis strains isolated from excised appendix of patients with phlegmonous or gangrenous appendicitis.

Out of 34 studied after-appendectomy tissues of adult and child patients 86 different strains of anaerobes were isolated. The antibiotic susceptibility of 30 isolated B. fragilis strains was tested using E tests. All studied strains were sensitive to imipenem, clindamycin and penicillin/tazobactam. Sensitivity to penicillin and cefoxitin was variable among these strains. One strain resistant to metronidazole (MIC--256 mg/L) and 3 strains with increased MIC to metronidazole were detected. Most of isolated strains were beta-lactamase producers.

[Surveillance of hospital infections in Poland--current condition and prospects]. / Nadzór nad zakazeniami szpitalnymi w Polsce--stan aktualny i mozliwosci rozwoju.

This paper outlines the current achievements in the control of hospital acquired infections in modern countries as well as in Poland in recent years. Studies related to the incidence of hospital-acquired infections have been conduced in western Europe, Scandinavia, the United States, and many other countries around the world. Because of these already completed studies, we are able to develop epidemiologic analysis specifically centered upon the incidence and increased costs involved with hospital-acquired infections. In Poland this type of surveillance was unable to be attained until long after its institution. However, over the past few years, the Polish Society of Hospital-Acquired Infection, has worked to bring recognition of the seriousness of this problem to a representative group of Polish hospitals. One of the most important conclusions reached was lack of departmental control which, using standards previously agreed upon by modern countries, could provide the necessary surveillance over hospital-acquired infections. Currently, surveillance is carried out by treating physicians without the help of specially-trained infection control nurses, epidemiologists and medical microbiologists. The basic challenge for the Polish health service is that of the development and realization of a professional infection control team. This professional team would work develop guidelines for the protection of patients and hospital personnel from hospital-acquired infections.

[Hospital acquired pneumonia--analysis of frequency and etiology in Polish hospitals in 1998]. / Szpitalne zapalenia pluc--analiza czestosci wystepowania oraz czynników etiologicznych tego zakazenia w Polskich szpitalach w 1998 roku.

Hospital-acquired pneumonia (HAP) is one of the most frequently occurring hospital infections in the world. This study describes the incidence of HAP in Poland, as well as the specific risk factors leading to this type of infection in Polish hospitals; including those of patient age, length of hospitalization, and use of mechanical ventilation. The epidemiology of HAP as well as treatment resistance of various causal organisms was studied. Data for this study was acquired from the Registry of Hospital-acquired Infectious Diseases for the year 1998. Out of 329,608 hospital-acquired infections in all patients except newborns, 920 were found to be HAP. This study showed that of every 1000 hospital admissions three patients developed HAP (0.3%). Death occurred in 260 of 920 HAP cases or 30%; and HAP found to be the direct cause of death in 66 of the 260 cases (25%). The greatest incidence of HAP was found to occur in patients older than 75 years, was directly related to the length of hospital stay, and was higher in patients on mechanical ventilation longer than 10 days. The most frequently isolated causal agents were the Gram-negative rods (Pseudomonas aeruginosa, Acinetobacter sp., Klebsiella sp., Enterobacter sp.), and Staphylococcus aureus. Streptococcus pneumoniae and Haemophilus influenzae were found in only 2% and 4% of cases, respectively, and thus were the least likely causes of HAP in this population. It was found that the percentage of methicillin-resistant strains of Staphylococcus aureus was very high (55% to 60%); vancomycin-resistant enterococci were only found in patients who did not undergo surgery. The isolated strains of Pseudomonas aeruginosa showed marked resistance to chinolones (58-76%) and to imipen (approximately 20%). In the Enterobacteriaceae family, Klebsiella sp. was found to be resistant to third-generation cephalosporins (56-73%) and Enterobacter sp. resistant in 55% to 81% of the isolates.

[Dominant etiological factors of urinary tract infections in various hospital departments and their resistance to chemotherapeutic agents]. / Czynniki etiologiczne zakazen ukladu moczowego dominujace na róznych oddzialach szpitalnych i ich opornosc na chemioterapeutyki.

PURPOSE: The purpose of this study was the determination of the incidence of urinary tract infection (UTI) in patients hospitalized in specific wards, and the analysis of the factors influencing the incidence of infection. METHODS: 329,608 hospital infection registration cards taken from the Polish national program for registration of hospital infections were analysed. This programme is based on a unified registration card system and on the definitions of particular types of hospital-acquired infections provided by the CDC (Centers for Disease Control, Atlanta, Georgia, USA). Statistical analysis was performed using the Statistica programme. RESULTS: 1,422 cases of hospital-acquired UTI, making up 21% of total hospital-acquired infections, were found. Six hundred sixty-six microbes were isolated from this total number of cases. The dominant pathogens were: Escherichia coli (31%), followed by Pseudomonas aeruginosa (13%), and Enterococcus sp. (12%). Hospital-acquired UTI occurred most often in maternity wards, gynaecology departments and intensive care units. Microbiological confirmation was obtained for only 45% of the clinically diagnosed cases of UTI. A disquieting increase of Pseudomonas aeruginosa resistant to chinolones was observed as well as extremely high resistance to aminoglycosides in Enterococcus sp. CONCLUSIONS: Urinary tract infections (UTIs) are the second most common form of hospital-acquired infection. Causal agents of hospital-acquired UTIs differed, depending upon the specific ward to which the patient is admitted. The most frequently isolated pathogens were Escherichia coli, Pseudomonas aeruginosa and Enterococcus sp. Microbiological confirmation of the clinically diagnosed cases of urinary tract infection is absolutely necessary, as well as a better cooperation between practicing physicians and microbiologists in the detection of hospital-acquired infection and interpretation of results.

[Mortality associated with hospital acquired infections. Analysis based upon data from the Polish National Program for Control of Infection in 1998]. / Smiertelnosc zwiazana z zakazeniami szpitalnymi. Analiza oparta na danych uzyskanych w ramach ogólnopolskiego programu kontroli zakazen w 1998 roku.

OBJECTIVE: The purpose of this study was to analyse patient mortality connected with hospital acquired infections in Polish hospitals during the year 1998. METHODS: Data was taken from 96 hospitals involved in the National Programme for the Registration of Hospital-Acquired Infections which was established in 1998. The data concerning the presence or absence of 19 specific infection forms was gathered using the passive method. RESULTS: The mortality of patients during 1998 in which hospital acquired infections were the direct or indirect cause of death was 6.9% Pneumonia and blood stream infections were the most frequent causes of death in patients hospitalised in Intensive Care Units. The most important risk factors for the development of hospital acquired infections, included old age, mechanical ventilation and urinary bladder catheterization. CONCLUSIONS: Selected epidemiological indicators for mortality rate were similar to those reported in countries with high quality infection control. A marked difference, however, was seen when comparing dating involving blood stream infections. The level of morbidity was found to be less in Poland than in developed countries. The authors feel that this low morbidity may be secondary to the decreased frequency of blood culture testing in Poland.

[Bacterial flora of the respiratory tract in artificially ventilated patients]. / Flora bakteryjna dróg oddechowych u chorych sztucznie wentylowanych.

Patients treated in ICUs are at particular risk for nosocomial infections. Within this group a ventilator-associated pneumonia still constitutes a major problem. Highly virulent hospital strains, existing in ICUs, can colonize patients' upper respiratory tract. Therefore this study aimed at analysing the organisms found in patients who required mechanical ventilation in ICUs. The same types of bacteria with the same (high) rate colonized upper airways, trachea and stomach of patients treated at the intensive Care Unit. It is suggested that the presence of Gram negative bacilli may serve as a marker of possible pneumonia in artificially ventilated patients. It is also important to check whether the organisms isolated from the larynx or trachea are only colonizing agents or are representative for the etiologic factors of pneumonia. Antibiotic therapy based on the sensitivity tests could be inadequate.

[Bacterial flora of the vagina and the effect of endogenous and exogenous factors on its changes]. / Flora bakteryjna pochwy i wplyw czynników egzo- i endogennych na jej zmiany.

The paper describes composition of the bacterial vaginal flora and its basic mechanisms enabling coexistence of different bacterial species residing in this region. A role of the dominant bacteria in maintaining stability of the microflora was stressed. Also various factors influencing ecological balance of the vaginal flora were presented.

[Effect of vaginal tampons on bacterial flora of the lower genitalia]. / Wplyw tamponów dopochwowych na flore bakteryjna dolnego odcinka dróg rodnych.

A constant risk of genitary tract infections, especially during menstrual bleeding, poses several questions concerning and effect of various protective measures used during menstruation. Such measures, especially vaginal tampons, have direct contact with vaginal mucosa, and may affect normal flora. One of the most frequent causes of complaints are infections or changes in the normal flora. Several studies indicate that the intervaginal tampons did not markedly change normal flora composition due to the introduction of bacteria from the environment. However, inflammatory states of genitary tract related to the use of intravaginal tampons is merely due to irritative action of fibers used for manufacture of such tampons. Currently used raw materials are not producing any pathologies. Several authors have shown that the health hazards produced by such tampons related to toxic shock during menstruation have been due to highly absorbable fibers used for their manufacture. Actually such materials are not used anymore. Tampons used according to manufactures' recommendations are safe, and do not produce inflammatory states.

Nasal carriage of Staphylococcus aureus and its influence on hospital infections caused by methicillin-resistant strains.

A short review of the literature on the actual epidemiological situation related to nosocomial infections caused by methicillin-resistant Staphylococcus aureus and the importance of the nasal carriage of this pathogen is given together with selected data derived from our own studies on these problems.

Effect of mupirocin on nasal carriage of Staphylococcus aureus.

Mupirocin eliminates nasal carriage of Staphylococcus aureus among medical and surgical personnel for periods varying from several weeks up to one year. In persons recolonized after therapy densities of S. aureus populations in nares were much lower than in the same persons before therapy.

[Piglets as a model for studying the activity of staphylococcal shock syndrome toxin (TSST-1)]. / Miniaturowe swine jako model dzialania gronkowcowej toksyny wstrzasu toksycznego (TSST-1).

In this study the influence of toxic shock syndrome toxin produced by Staphylococcus aureus on the organism of piglets of Minnesota race is presented. Animals were tested in two groups: conventional and gnotobiotic and they were given the toxin intradermally in two doses 10 and 100 micrograms/kg of body weight. It was shown that piglets are sensitive to the toxin which induced rise of body temperature, various clinical symptoms and in functional changes of several organs as shown by analytical studies. Gnotobiotic animals showed lower susceptibility to the toxin as compared to conventional piglets what suggest a participation of endotoxin in pathologic process.