Antimicrobial activity of ceftazidime-avibactam and comparators against Pseudomonas aeruginosa and Enterobacterales collected in Croatia, Czech Republic, Hungary, Poland, Latvia and Lithuania: ATLAS Surveillance Program, 2019.

Antimicrobial susceptibility of clinical isolates collected from sites in central Europe in 2019 was tested by CLSI broth microdilution method and EUCAST breakpoints. Most active were amikacin, ceftazidime-avibactam and colistin; respectively, susceptibility rates among P. aeruginosa (n = 701) were 89.2%, 92.2% and 99.9%; difficult-to-treat (DTR) isolates, 62.5%, 37.5% and 100%; multidrug-resistant (MDR) isolates, 68.3%, 72.9% and 99.5%; meropenem-resistant (MEM-R), metallo-ß-lactamase-negative (MBL-negative) isolates, 72.8%, 78.6% and 100%. Among Enterobacterales (n = 1639), susceptibility to ceftazidime-avibactam, colistin and tigecycline was ≥ 97.9%; MDR Enterobacterales, 96.8%, 94.4% and 100%, respectively; DTR isolates, ≥ 76.2% to ceftazidime-avibactam and colistin; MEM-R, MBL-negative isolates, ≥ 90.0% to ceftazidime-avibactam and colistin.

Microbiological diagnostics of bloodstream infections in Europe-an ESGBIES survey.

OBJECTIVES: High-quality diagnosis of bloodstream infections (BSI) is important for successful patient management. As knowledge on current practices of microbiological BSI diagnostics is limited, this project aimed to assess its current state in European microbiological laboratories. METHODS: We performed an online questionnaire-based cross-sectional survey comprising 34 questions on practices of microbiological BSI diagnostics. The ESCMID Study Group for Bloodstream Infections, Endocarditis and Sepsis (ESGBIES) was the primary platform to engage national coordinators who recruited laboratories within their countries. RESULTS: Responses were received from 209 laboratories in 25 European countries. Although 32.5% (68/209) of laboratories only used the classical processing of positive blood cultures (BC), two-thirds applied rapid technologies. Of laboratories that provided data, 42.2% (78/185) were able to start incubating BC in automated BC incubators around-the-clock, and only 13% (25/192) had established a 24-h service to start immediate processing of positive BC. Only 4.7% (9/190) of laboratories validated and transmitted the results of identification and antimicrobial susceptibility testing (AST) of BC pathogens to clinicians 24 h/day. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry from briefly incubated sub-cultures on solid media was the most commonly used approach to rapid pathogen identification from positive BC, and direct disc diffusion was the most common rapid AST method from positive BC. CONCLUSIONS: Laboratories have started to implement novel technologies for rapid identification and AST for positive BC. However, progress is severely compromised by limited operating hours such that current practice of BC diagnostics in Europe complies only partly with the requirements for optimal BSI management.

How to: identify non-tuberculous Mycobacterium species using MALDI-TOF mass spectrometry.

BACKGROUND: The implementation of MALDI-TOF MS for microorganism identification has changed the routine of the microbiology laboratories as we knew it. Most microorganisms can now be reliably identified within minutes using this inexpensive, user-friendly methodology. However, its application in the identification of mycobacteria isolates has been hampered by the structure of their cell wall. Improvements in the sample processing method and in the available database have proved key factors for the rapid and reliable identification of non-tuberculous mycobacteria isolates using MALDI-TOF MS. AIMS: The main objective is to provide information about the proceedings for the identification of non-tuberculous isolates using MALDI-TOF MS and to review different sample processing methods, available databases, and the interpretation of the results. SOURCES: Results from relevant studies on the use of the available MALDI-TOF MS instruments, the implementation of innovative sample processing methods, or the implementation of improved databases are discussed. CONTENT: Insight about the methodology required for reliable identification of non-tuberculous mycobacteria and its implementation in the microbiology laboratory routine is provided. IMPLICATIONS: Microbiology laboratories where MALDI-TOF MS is available can benefit from its capacity to identify most clinically interesting non-tuberculous mycobacteria in a rapid, reliable, and inexpensive manner.

Microbiological criteria in non-tuberculous mycobacteria pulmonary disease: a tool for diagnosis and epidemiology.

SETTING: The value of microbiological criteria in diagnosing non-tuberculous mycobacteria pulmonary disease (NTM-PD) and monitoring its epidemiology is unknown. OBJECTIVES: To correlate the rate of NTM-PD based on microbiological criteria (American Thoracic Society/Infectious Diseases Society of America [ATS/IDSA] or stricter microbiological criteria) compared with the full ATS/IDSA criteria, to assess the positive predictive value (PPV) of different microbiological criteria in predicting NTM-PD, and to evaluate the clinical relevance of different NTM species. DESIGN: Retrospective study of all patients with pulmonary NTM isolates in Croatia during an 8-year period. NTM species were divided into low, intermediate and high clinical relevance groups for additional analyses. RESULTS: Good correlation between both microbiological and full ATS/IDSA criteria was observed. The PPV of stricter and ATS/IDSA microbiological criteria was respectively 93.3% and 59.8%. The usefulness of microbiological criteria varied between groups. ATS/IDSA microbiological criteria had a PPV of 89.8% in the high relevance group, while in the intermediate relevance group, the PPV of stricter and ATS/IDSA microbiological criteria was respectively 94.3% and 63.4%. CONCLUSIONS: Microbiological criteria are useful in detecting NTM-PD, allowing laboratory-based monitoring. Stricter criteria should be used for species of low clinical relevance, and less stringent criteria for species of high relevance in the local setting.

Direct identification of mycobacteria from smear-positive samples using real-time polymerase chain reaction.

The aim of the present study was to investigate whether real-time polymerase chain reaction (PCR) has a low identification rate for samples with low acid-fast bacilli (AFB) grades, including those obtained using bronchoscopy. When 50 smear-positive samples were compared by AFB score and PCR result, PCR was 100% successful in identifying AFB 2+ and AFB 3+ samples. However, only 14 of 26 (52%) AFB 1+ samples were identified. In paucibacillary smear-positive samples, PCR is not reliable enough to exclude tuberculosis, but in smear-positive patients with high AFB grades PCR can immediately change the clinical management of the disease.

Comparative analysis of azithromycin and clarithromycin efficacy and tolerability in the treatment of chronic prostatitis caused by Chlamydia trachomatis.

A total of 123 patients, older than 18 years of age, with symptoms of chronic prostatitis and inflammatory findings as well as the presence of Chlamydia trachomatis confirmed by DNA/RNA DIGENE hybridization method in expressed prostatic secretion or in voided bladder urine collected immediately after prostatic massage, were examined. The patients were randomized to receive a total of 4.5 g of azithromycin for 3 weeks, given as a 3-day therapy of 1 x 500 mg weekly or clarithromycin 500 mg b.i.d. for 15 days. Patients' sexual partners were treated at the same time. Clinical and bacteriological efficacy were evaluated 4-6 weeks after the end of therapy. In the group of patients with chronic chlamydial prostatitis the eradication rates (azithromycin 37/46, clarithromycin 36/45) and the clinical cure rates (azithromycin 32/46, clarithromycin 32/45) were not significantly different with regards to the administered drug (p > 0.05). In the group of patients with asymptomatic chlamydial prostatitis the eradication rates (azithromycin 11/16, clarithromycin 10/15) were not significantly different with regards to the administered drug (p = 1.00, OR = 1.1).