The use of rapid test QuikRead go® Strep A in bacterial pharyngotonsillitis diagnosing and therapeutic decisions.

Group A Streptococci (GAS) are the main causative agents of bacterial pharyngitis, which require antibiotic therapy. Rapid diagnostic tests detecting GAS combined with Centor/McIsaac score enable accurate differential diagnosis (viral vs. bacterial) and prompt commencement of targeted treatment. The aim of this study was to assess the specificity, sensitivity, PPV and NPV of QuikRead go® Strep A (Orion Diagnostica Oy, Finland) recommended for the detection of GAS in pharyngeal swabs. Quick diagnostic test results were compared with physical examination findings, Centor/McIsaac score and results of reference testing (conventional microbial cultures). The study group of 96 participants consisted of 44 women (46%) and 52 men (54%); children aged 3-14 years constituted 46% of the patients. S. pyogenes were cultured from 43 of 96 pharyngeal swabs. Almost half of all positive samples (47%, n = 20) were collected from children aged 3 to 14 years. Positive GAS cultures were confirmed in 33% of patients with Centor/McIsaac score of 2 points, 48% of patients with score of 3, and 50% of patients with score of 4-5. Microbial cultures confirmed the positive results of QuikRead go® Strep A test in 83% of cases. Test specificity and sensitivity were calculated for the entire study group, which were 85% and 91%, respectively. The PPV of the test was 83% and its NPV was 92%. Using quick tests to detect GAS antigens appears a good alternative to conventional microbial diagnosis of strep throat, as it enables making a diagnosis and deciding on treatment plan in one appointment.

Etiology and antibiotic susceptibility of bacterial pathogens responsible for community-acquired urinary tract infections in Poland.

Urinary tract infections (UTIs) are some of the most common infections in both community and hospital settings infections. With their high rate of incidence, recurrence, complications, diverse etiologic agents, as well as growing antibiotic resistance, UTIs have proven to be a serious challenge for medical professionals. The aim of this study was to obtain data on the susceptibility patterns of pathogens responsible for UTIs in Poland to currently used antibiotics. A total of 396 bacterial isolates were collected between March and May 2013 from 41 centers in all regions of Poland. The majority of isolates were from adult patients (96.2 %); 144 (37.8 %) patients were diagnosed with uncomplicated UTI, while the remaining 237 (62.2 %) had a complicated infection. The most prevalent pathogen was Escherichia coli (71.4 %), followed by Klebsiella spp. (10.8 %) and the Proteae group (7.6 %). Escherichia coli was responsible for 80.6 % of cases of uncomplicated and 65.8 % of complicated infections. Only 65.8 % of E. coli isolates were susceptible to ciprofloxacin (uncomplicated 75.9 %, complicated 58.3 %), 64.0 % to nitrofurantoin (67.2 %, 62.8 %), 65.1 % to trimethoprim/sulfamethoxazole (68.1 %, 62.8 %), and 66.4 % to fosfomycin (77.6 %, 62.2 %). Among E. coli isolates from all UTIs, only 43.4 % were susceptible to ampicillin, with 47.4 % from uncomplicated compared with 40.4 % from complicated infections; 88.2 % to amoxicillin/clavulanic acid (91.4 % vs. 85.9 % complicated); 90.1 % to cefuroxime (93.1 %, 87.8 %); and 94.1 % to cefotaxime (98.2 %, 91.0 %). Thirty-five strains (10.4 %) were capable of producing extended-spectrum ß-lactamases (ESBLs). This study demonstrates an increase in multidrug-resistant strains, especially among the leading pathogens associated with UTIs, including E. coli, Klebsiella spp., and Proteus spp.

Streptococcus suis in invasive human infections in Poland: clonality and determinants of virulence and antimicrobial resistance.

The purpose of this study was to perform an analysis of Streptococcus suis human invasive isolates, collected in Poland by the National Reference Centre for Bacterial Meningitis. Isolates obtained from 21 patients during 2000-2013 were investigated by phenotypic tests, multilocus sequence typing (MLST), analysis of the TR9 locus from the multilocus variable number tandem repeat (VNTR) analysis (MLVA) scheme and pulsed-field gel electrophoresis (PFGE) of SmaI-digested DNA. Determinants of virulence and antimicrobial resistance were detected by polymerase chain reaction (PCR) and analysed by sequencing. All isolates represented sequence type 1 (ST1) and were suggested to be serotype 2. PFGE and analysis of the TR9 locus allowed the discrimination of four and 17 types, respectively. Most of the isolates were haemolysis- and DNase-positive, and around half of them formed biofilm. Genes encoding suilysin, extracellular protein factor, fibronectin-binding protein, muramidase-released protein, surface antigen one, enolase, serum opacity factor and pili were ubiquitous in the studied group, while none of the isolates carried sequences characteristic for the 89K pathogenicity island. All isolates were susceptible to penicillin, cefotaxime, imipenem, moxifloxacin, chloramphenicol, rifampicin, gentamicin, linezolid, vancomycin and daptomycin. Five isolates (24 %) were concomitantly non-susceptible to erythromycin, clindamycin and tetracycline, and harboured the tet(O) and erm(B) genes; for one isolate, lsa(E) and lnu(B) were additionally detected. Streptococcus suis isolated in Poland from human invasive infections belongs to a globally distributed clonal complex of this pathogen, enriched in virulence markers. This is the first report of the lsa(E) and lnu(B) resistance genes in S. suis.

Evaluation of the BD Phoenix automated identification and susceptibility testing system in clinical microbiology laboratory practice.

The Phoenix Automated Microbiology System (BD Biosciences, USA) is a new, fully automated system for the rapid identification and antimicrobial susceptibility testing of gram-positive and gram-negative bacteria. The objective of this study was to evaluate the quality of performance of the Phoenix system in the identification and antimicrobial susceptibility testing of 260 gram-negative ( n=174) and gram-positive ( n=86) isolates collected from Polish hospitals in recent years. Two Phoenix panel types for identification/antimicrobial susceptibility testing, NMIC/ID-5 for gram-negative rods and PMIC/ID-4 for gram-positive cocci, were used in the analysis according to the manufacturer's recommendations. The results produced by the system were compared with data obtained by reference or conventional microbiological methods. A high rate of agreement between the Phoenix and the conventional methods was observed for identification, ranging from 100% for gram-positive cocci to 96.0% for gram-negative nonfermenters and 92.5% for members of the family Enterobacteriaceae. Similarly, a high level of agreement characterized the antimicrobial susceptibility data obtained with the Phoenix and by the agar dilution method (2,361 test results). For staphylococci, enterococci and Enterobacteriaceae, the methods were 100% concordant in determining the category of susceptibility of isolates to the majority of the antimicrobial agents tested. A category agreement value of below 90% was found for the susceptibility of enterococci and gram-negative nonfermenters to ciprofloxacin (84.6% and 88.5%, respectively) and for susceptibility of Stenotrophomonas maltophilia to trimethoprim-sulfamethoxazole (80.0%).

Outbreak of mupirocin-resistant staphylococci in a hospital in Warsaw, Poland, due to plasmid transmission and clonal spread of several strains.

An outbreak of mupirocin-resistant (MuR) staphylococci was investigated in two wards of a large hospital in Warsaw, Poland. Fifty-three MuR isolates of Staphylococcus aureus, S. epidermidis, S. haemolyticus, S. xylosus, and S. capitis were identified over a 17-month survey which was carried out after introduction of the drug for the treatment of skin infections. The isolates were collected from patients with infections, environmental samples, and carriers; they constituted 19.5% of all staphylococcal isolates identified in the two wards during that time. Almost all the MuR isolates were also resistant to methicillin (methicillin-resistant S. aureus and methicillin-resistant coagulase-negative staphylococci). Seven of the outbreak isolates expressed a low-level-resistance phenotype (MuL), whereas the remaining majority of isolates were found to be highly resistant to mupirocin (MuH). The mupA gene, responsible for the MuH phenotype, has been assigned to three different polymorphic loci among the strains in the collection analyzed. The predominant polymorph, polymorph I (characterized by a mupA-containing EcoRI DNA fragment of about 16 kb), was located on a specific plasmid which was widely distributed among the entire staphylococcal population. All MuR S. aureus isolates were found to represent a single epidemic strain, which was clonally disseminated in both wards. The S. epidermidis population was much more diverse; however, at least four clusters of closely related isolates were identified, which suggested that some strains of this species were also clonally spread in the hospital environment. Six isolates of S. epidermidis were demonstrated to express the MuL and MuH resistance mechanisms simultaneously, and this is the first identification of such dual MuR phenotype-bearing strains. The outbreak was attributed to a high level and inappropriate use of mupirocin, and as a result the dermatological formulation of the drug has been removed from the hospital formulary.