Evaluation of the BioFire® FilmArray® Pneumonia plus Panel for Detecting Bacterial Etiological Agents of Lower Respiratory Tract Infections in an Oncologic Hospital. Comparison with Conventional Culture Method.

Conventional methods used to determine pneumonia pathogens are characterized by low sensitivity and long turnaround times. Introducing new tests with better parameters in patients at higher risk of infections is highly anticipated. The results of the conventional quantitative culture method (CM) in determining the bacterial etiology of pneumonia were compared with the results of the Pneumonia plus Panel test (PNP; BioFire® Diagnostics, USA) in 79 samples of bronchoalveolar lavage (BAL). Materials were collected from 79 patients with suspected pneumonia treated in an oncologic hospital due to solid tumors. Only 16/79 BAL samples (20.3%) were true positive (TP) for bacterial etiology in CM vs. 27/79 samples (34.2%) true positive in the PNP test. The total agreement between methods of interpreting the result (positive or negative) was 84.8%. The most prevalent pathogens in both methods were Staphylococcus aureus, followed by Escherichia coli, Pseudomonas aeruginosa, and Haemophilus influenzae. The PNP test identified several respiratory pathogens that were not grown in culture. The semiquantitative value reported by the PNP test was higher than that reported by culture. The PNP test vs. combined test (PNP test and CM methods) demonstrated positive predictive value (PPV) and negative predictive value (NPV) values of 100.0% and 98.1%, and the sensitivity and specificity were 96.4% and 100.0%. The PNP test is a good tool for determining the etiology of bacterial pneumonia and may support the care of an oncologic patient. However, further large-sample studies are needed to research in strictly defined groups of oncologic patients.

Occurrence of Beta-Lactamases in Colistin-Resistant Enterobacterales Strains in Poland - a Pilot Study.

Sixty-five colistin-resistant Enterobacterales isolates recovered from different clinical specimens were analyzed. The strains were collected in 12 hospitals all over Poland within a period of nine months. Strains were analyzed for eight genes from the mcr family. The presence of mcr-1 gene was detected in three Escherichia coli strains. The 45/65 isolates were identified as ESBL producers. CTX-M-1-like enzymes were the most common ESBLs (n = 40). One E. coli and seven Klebsiella pneumoniae strains produced carbapenemases, with the NDM being produced by five isolates. Among all the strains tested, four and five were resistant to new drugs meropenem/vaborbactam and ceftazidime/avibactam, respectively.

Clinical and Molecular Findings of Infections Caused by Extended-Spectrum ß-Lactamase-Producing Enterobacterales in Patients with Solid Tumors: A Single-Center Study.

Infectious complications caused by multidrug-resistant bacteria are a serious clinical and therapeutic problem. Our study aimed to analyze the genetic characteristics of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-E) that cause multidrug-resistant infections in patients with solid tumors. Identification of ESBL-encoding genes was performed by polymerase chain reaction (PCR) and sequencing. The clonal relationship of the isolates was evaluated by pulsed-field gel electrophoresis. Multilocus sequence typing (MLST) was carried out for selected Escherichia coli and Klebsiella pneumoniae isolates. All E. coli strains were classified into phylogenetic groups using the PCR-based approach. There were 735 patients with clinical symptoms of infections tested, of which 44 (6.0%) were positive for ESBL-E on genotypic testing. The most frequent organism was E. coli (n = 24, 54.5%), followed by K. pneumoniae (n = 13, 29.5%), Proteus mirabilis (n = 3, 6.8%), Enterobacter cloacae cplx (n = 2, 4.5%), and Klebsiella oxytoca (n = 2, 4.5%). Overall, 31 (70.5%) of the ESBL-E isolates carried only blaCTX-M-1-like genes, and the genes were found to be blaCTX-M-15 (n = 30, 68.2%) or blaCTX-M-3 (n = 1, 2.3%). Eleven strains (25%) had blaCTX-M-9-like genes, mostly blaCTX-M-27 (n = 10, 22.7%) and unique blaCTX-M-65 (n = 1, 2.3%). One isolate possessed both blaCTX-M-15 and blaCTX-M-27 genes, and another one produced TEM-12 ESBL. MLST analysis revealed E. coli sequence type (ST) 131 and ST361, and K. pneumoniae ST16, ST307, and ST437. Among E. coli isolates, the B2 phylogenetic group was predominant. Most of the strains showed resistance to third-generation cephalosporins and fluoroquinolones, and susceptibility to aminoglycosides and carbapenems. Patients with solid cancer and ESBL-E infections require special management since they are a population with a high threat of antibiotic-resistant infections. Carbapenems and aminoglycosides remain active antibiotics against these infections.

Characteristics of ESBL-Producing Enterobacterales Colonizing the Gastrointestinal Tract in Patients Admitted to the Oncological Hospital.

We analyzed the prevalence and genetic characteristics of the extended-spectrum ß-lactamases (ESBLs)-producing Enterobacterales isolated from adult patients hospitalized in the oncological center in 2019. Out of 9372 patients admitted to the hospital, 1373 had been in various medical facilities during the last year, which was an indication to perform a screening test for ESBL-producing Enterobacterales colonizing their gastrointestinal tract. In eighty-three patients (6.1%), 85 ESBL producers were detected. These isolates included the following: Escherichia coli (n = 67; 78.8%), Klebsiella pneumoniae (n = 14; 16.5%), Enterobacter cloacae cplx (n = 3; 3.5%), and Klebsiella oxytoca (n = 1; 1.2%). CTX-M-1-like enzymes were the most common ESBLs (n = 67; 78.8%). Two K. pneumoniae isolates (2/85; 2.4%) additionally produced New Delhi-metallo-ß-lactamases (NDM). All isolates, except for K. oxytoca, were typed by pulsed-field gel electrophoresis (PFGE) and demonstrated high genetic diversity. The most prevalent phylogroups of E. coli were B2 group (n = 30; 44.8%), followed by A group (n = 25; 37.3%). These observations have motivated us to investigate the link between ESBL-E colonization and infection among patients with solid tumors.

Colistin Resistance in Enterobacterales Strains - A Current View.

Colistin is a member of cationic polypeptide antibiotics known as polymyxins. It is widely used in animal husbandry, plant cultivation, animal and human medicine and is increasingly used as one of the last available treatment options for patients with severe infections with carbapenem-resistant Gram-negative bacilli. Due to the increased use of colistin in treating infections caused by multidrug-resistant (MDR) bacteria, the resistance to this antibiotic ought to be monitored. Bacterial resistance to colistin may be encoded on transposable genetic elements (e.g. plasmids with the mcr genes). Thus far, nine variants of the mcr gene, mcr-1 - mcr-9, have been identified. Chromosomal resistance to colistin is associated with the modification of lipopolysaccharide (LPS). Various methods, from classical microbiology to molecular biology methods, are used to detect the colistin-resistant bacterial strains and to identify resistance mechanisms. The broth dilution method is recommended for susceptibility testing of bacteria to colistin.Colistin is a member of cationic polypeptide antibiotics known as polymyxins. It is widely used in animal husbandry, plant cultivation, animal and human medicine and is increasingly used as one of the last available treatment options for patients with severe infections with carbapenem-resistant Gram-negative bacilli. Due to the increased use of colistin in treating infections caused by multidrug-resistant (MDR) bacteria, the resistance to this antibiotic ought to be monitored. Bacterial resistance to colistin may be encoded on transposable genetic elements (e.g. plasmids with the mcr genes). Thus far, nine variants of the mcr gene, mcr-1 ­ mcr-9, have been identified. Chromosomal resistance to colistin is associated with the modification of lipopolysaccharide (LPS). Various methods, from classical microbiology to molecular biology methods, are used to detect the colistin-resistant bacterial strains and to identify resistance mechanisms. The broth dilution method is recommended for susceptibility testing of bacteria to colistin.

Activity of dalbavancin against gram-positive cocci isolated from skin and soft tissue infections in Poland.

A total of 368 Gram-positive cocci from ABSSI were included in the study. S. aureus and S. pyogenes were susceptible to dalbavancin with MIC50 0.016 mg/L and MIC90 0.032 mg/L for MSSA and MIC50 0.032 mg/L and MIC90 0.047 mg/L for MRSA; MICs for S. pyogenes were ≤0.002-0.008 mg/L; for E. faecalis and E. faecium, ranging 0.016-0.12 mg/L and 0.012-≥32 mg/L, respectively; MICs for VRE were 0.032-0.125 mg/L.

The Usefulness of Chromogenic Media for Qualitative and Semi-Quantitative Diagnostic of Urinary Tract Infections.

The aim of this study was to evaluate the usefulness of chromogenic media for isolation of bacteria from urine and direct identification of UTI pathogens. A total of 100 urine specimens were inoculated on blood agar and MacConkey agar as a reference method and on the following media to be tested: chromID® CPS® Elite (CPSE, bioMérieux), CHROMagarTM Orientation (BioMaxima), BD CHROMagar Orientation Medium (ORI, Becton Dickinson), CHROMagarTM Orientation (ORIE, Graso) and Brillance UTI Clarity Agar (UTI C, Oxoid). After a 24-hour incubation period, 47 Gram-positive cocci and 62 Gram-negative rods were observed. The specificity and sensitivity of all chromogenic media was 97.3% and 93.5% respectively for qualitative diagnostic; and 81.9% and 81.3% respectively for semi-quantitative diagnostic. The mean PPV and NPV of the chromogenic media were 98.7% and 87.7% for qualitative UTI diagnostic, and 90.9% and 71.9% respectively for semi-quantitative diagnostic.

Streptococcus anginosus (milleri) Group Strains Isolated in Poland (1996-2012) and their Antibiotic Resistance Patterns.

Streptococcus anginosus, Streptococcus intermedius and Streptococcus constellatus form a group of related streptococcal species, namely the Streptococcus Anginosus Group (SAG). The group, previously called "milleri" had been rarely described until 1980/1990 as source of infections. Nowadays SAG bacteria are often described as pathogens causing predominantly purulent infections. The number of infections is highly underestimated, as SAG strains are often classified in the microbiology laboratory as less virulent "viridans streptococci" Epidemiological situation regarding SAG infections in Poland has been unrecognized, therefore we performed a retrospective analysis of strains isolated between 1996 and 2012. Strains suspected of belonging to SAG were re-identified using an automated biochemical approach (Vitek2) and MALDI-TOF MS. We performed first analysis of antibiotic resistance among SAG strains isolated in Poland using automated methods (Vitek2), disk diffusion tests and E-Tests. We also performed PCR detection of resistance determinants in antibiotic resistant strains. Clonal structure of analyzed strains was evaluated with PFGE and MLVF methods. All three species are difficult to distinguish using automated diagnostic methods and the same is true for automated MIC evaluation. Our analysis revealed SAG strains are rarely isolated in Poland, predominantly from purulent infections. All isolates are very diverse on the genomic level as estimated by PFGE and MLVF analyses. All analyzed strains are sensitive to penicillin, a substantial group of strains is resistant to macrolides and the majority of strains are resistant to tetracycline.

Usefulness of CHROMagar Candida Medium, Biochemical Methods--API ID32C and VITEK 2 Compact and Two MALDI-TOF MS Systems for Candida spp. Identification.

This study was conducted to compare of the yeasts identification results obtained with two new systems using the MALDI-TOF MS technique with the ones obtained using the routine identification methods of Candida spp. in clinical microbiology laboratories. All 124 Candida spp. isolates were recovered from the routine examination of clinical specimens in microbiological laboratories and collected in the Centre of Quality Control in Microbiology in Warsaw (Poland). Our findings confirm the high agreement (98%) of fungal identification using the standard, biochemistry laboratory methods and mass spectrometry technique.

[Severe sepsis after dog bite caused by Capnocytophaga canimorsus]. / Ciezka sepsa wywolana przez Capnocytophaga canimorsus po pogryzieniu przez psa.

We describe a case of a life-threatening septicemia resulting from a previous dog bite wound. The isolated bacterium was Capnocytophaga canimorsus, a slow-growing Gram-negative bacillus commonly found in dog saliva. Known risk factors for invasive C. canimorsus infections are alcohol abuse, cigarette smoking, splenectomy or other forms of immunosuppression. Any clinician seeing patients with a history of a dog bite should consider this pathogen as a causative agent and take detailed history regarding exposure to animals.

Characterization of Rhodococcus equi isolates from submaxillary lymph nodes of wild boars (Sus scrofa), red deer (Cervus elaphus) and roe deer (Capreolus capreolus).

Rhodococcus equi is a soil saprophyte and an opportunistic pathogen causing infections in animals, and rarely in humans. The presence of R. equi in tissues and faeces of some wild animal species was demonstrated previously. In this study we characterized R. equi isolates from submaxillary lymph nodes of free-living wild boars (n=23), red deer (n=2) and roe deer (n=2). This is the first description of R. equi strains isolated from tissues of the Cervidae. All isolates were initially recognized as R. equi based on the phenotypic properties. Their identification was confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, detection of the choE gene and by sequence analysis of the 16S rRNA and rpoB genes. The presence of three plasmidic genes (traA, vapA and vapB) associated with R. equi virulence was investigated by PCR. In 16 wild boar isolates the traA and vapB genes were detected and they were located on virulence plasmids type 5, 7 or 11. The isolates from cervids and the remaining wild boar isolates were classified as avirulent based on a genotype traA(-)/vapA(-)B(-). In summary, these results confirm that wild boars can be a source of intermediately virulent R. equi strains, and indicate that red deer and roe deer can be a reservoir of avirulent R. equi strains.

New selective and differential chromogenic agar medium, chromID VRE, for screening vancomycin-resistant Enterococcus species.

This study aimed to evaluate the usefulness of a novel differential culture medium, chromID VRE agar, for the isolation of VRE in a clinical laboratory. It was shown that ChromID VRE agar may be useful for rapid and selective isolation of VRE especially after inclusion of broth enrichment step.

Heart rate variability and left ventricular mass in slim children and young adults with hypertension.

INTRODUCTION: Uncontrolled arterial hypertension brings direct and long-term sequelae in adult age, such as stroke, ischaemic heart disease with myocardial infarction, left ventricular hypertrophy or cardiac arrhythmia. AIM: To assess heart rate variability (HRV) spectral parameters and left ventricular mass in slim children with arterial hypertension, and to search for correlations between these two parameters. METHODS: 35 children aged 14.4+/-3.1 with idiopathic untreated arterial hypertension were enrolled. The control group included 30 age- and gender-matched healthy children (aged 14.1+/-2.9 years). In all analysed subjects an analysis of HRV parameters (high frequency (HF) and low frequency (LF) components) during 10-minute waking state and sleeping time was performed and left ventricular mass (LVM) as well as the left ventricular mass index (LVMI, g/m) were assessed based on echocardiographic measurements. RESULTS: There was no difference in LF during the waking state and sleep HF between the two groups, whereas HF values during the waking state were significantly lower (p<0.05) in children with hypertension. The LF/HF index from both registration intervals was significantly higher in the group of children with hypertension. In children with hypertension, LVM and LVMI correlated significantly with LF (r=0.32, p<0.05 and r=0.39, p<0.01). LVM and LVMI correlated positively with the LF/HF index during night hours (r=0.45, p<0.004 and r=0.49, p<0.002). No significant correlations were found between the analysed parameters in children from the control group. CONCLUSIONS: The increase of sympathetic activity during sleep correlates significantly with left ventricular mass and corrected left ventricular mass index in children with arterial hypertension.

Susceptibility testing and resistance phenotypes detection in bacterial pathogens using the VITEK 2 System.

A set of well characterized strains, collected in Polish hospitals, including Gram-negative (n = 93) and Gram-positive (n = 90) isolates was used in the study. The VITEK 2 AST-cards were used in the analysis according to the manufacturer's recommendations. Comparison of the susceptibility data obtained by the standard method and by VITEK 2 cards proved concordant in 99% of cases. Clinically important mechanisms were revealed by the VITEK 2 AES with >95% agreement with reference data including methicillin resistance in staphylococci (98%), high-level aminoglycoside resistance in enterococci (100%), VanA and VanB phenotypes in enterococci (100%), and ESBLs in Enterobacteriaceae (93.8%). The VITEK 2 AES System appears a reliable tool for the detection and interpretive reading of clinically important mechanisms of resistance and can be recommended for routine work.