Walter Marget and a brief history of paediatric infectious diseases in Munich, Germany.

Theodor Escherich (1857-1911) was one of the key players in early paediatric infectious diseases (PID). In fact, he can be regarded as the first paediatric infectious diseases physician and the founder of this subspecialty. During his long years in service for children, he spent 6 years at the Dr von Hauner children's hospital (1884-1890), laying the foundations for PID clinical care and research in Munich. Walter Marget, founder of this journal and co-founder of the German Society for Infectious Diseases (DGI) graduated from medical school in 1946 and practised in Munich since 1967. His tireless efforts went into establishing close links between clinical paediatrics and microbiological diagnostics culminating in the foundation of the Department of Antimicrobial Therapy and Infection Epidemiology at the Dr von Hauner children's hospital. Walter Marget was a key figure for PID in Germany having trained and supported many clinician scientists who followed in his footsteps. This article gives a brief overview of the history of PID in Munich while commemorating Walter Marget and his achievements in this field and for INFECTION.

Microbiologic diagnostics and pathogen spectrum in infective endocarditis of surgically treated patients: a five-year, retrospective, monocentric study.

PURPOSE: The spectrum of causative organisms in infective endocarditis (IE) has changed significantly in the last decades. Reliable pathogen detection is crucial for appropriate antimicrobial therapy for IE. The aim of the study was to evaluate the diagnostic value of microbiological methods for detecting the causative microorganism of IE and to analyze the spectrum of pathogens. METHODS: A total of 224 cases (211 unique patients, some with multiple surgeries) were included into this retrospective study. Patients were diagnosed with IE according to the modified Duke criteria from January 2016 to July 2021 and underwent heart valve surgery in a tertiary hospital. Pathogen detection was performed by blood culture, microbiological culture and 16S rDNA PCR of explanted heart valve material. RESULTS: A causative pathogen of IE was detected in 95.5% (n = 214) of cases. Blood cultures were positive in 83.3%, while a pathogen in the examined heart valve samples was identified in 32.6% by culture and in 88.2% by 16S rDNA PCR. A microorganism was identified by 16S rDNA PCR in 61.1% of blood culture negative cases but only in 19.4% by heart valve culture. The most common pathogens were Staphylococcus aureus (27%), viridans group streptococci (20%), enterococci (19%) and coagulase-negative staphylococci (CoNS 8%). Cutibacterium acnes (7%) was detected in prosthetic valve IE cases only. CONCLUSION: Blood culture as a comparatively non-invasive and straightforward technique remains an important and reliable method for initial detection of the causative organism in IE. Diagnostic stewardship programs should broadly emphasize proper collection of blood cultures, particularly sampling prior to any antibiotic treatment. Additionally, molecular testing using 16S rDNA tissue PCR can be used with culture techniques to increase the diagnostic yield, especially in the case of a negative blood culture.

Evaluation of two different semi-automated homogenization techniques in microbiological diagnosis of periprosthetic joint infection: disperser vs. bead milling method.

BACKGROUND: In microbiological diagnosis of periprosthetic joint infection (PJI) there is no consensus regarding the most suitable and optimal number of specimens to be cultured or the most effective technique of tissue processing. This comparative study analysed the accuracy of two semi-automated homogenization methods with special focus on the volume and exact origin of each sample. METHODS: We investigated a total of 722 periprosthetic tissue samples. PJI was defined according to the new scoring system for preoperative and intraoperative criteria. We compared the performance of our routinely used single tissue processing by disposable high-frequency disperser with the bead milling method. RESULTS: Eighty patients were included. Among forty classified PJIs, 34 patients yielded positive culture results. In 23 cases (68%) exact concordant results were generated with both techniques. However, in seven cases (20%) processing by the disperser and in four cases (12%) by bead milling provided additional positive samples, but without significant difference since the major definition criteria were met in all cases. The percentage of positive results was influenced by the volume and origin of the tissue samples. Results for small tissue samples tended to be better using the bead milling method. This might lead to improved preoperative arthroscopic diagnosis, as the volume of biopsies is generally limited. Six patients had negative results due to previous antimicrobial therapy. Forty other patients were classified as aseptic failures. Neither procedure resulted in any contamination. CONCLUSION: Both methods enable reliable processing of tissue samples for diagnosis of PJI and are suitable for routine use.

Corynebacterium spp. - problematic pathogens of the human respiratory tract (review of literature).

Corynebacterium spp. - representatives of the normal microflora of the human body, but their role in the development of diseases in both immunocompromised and immunocompetent patients is known. Corynebacterim spp. (C. pseudodiphtheriticum, C. striatum, C. amycolatum, C. accolens, C. argentoratense, etc.) is associated with diseases of the respiratory tract: tracheitis, pharyngitis, rhinosinusitis, bronchitis, etc. They can be transmitted by airborne droplets, household contact, and possibly by hematogenic pathways. Corynebacterim spp. toxins do not produce, but are capable of adhesion and invasion, biofilm formation, production of neuraminidase, hyaluronidase, and hemolysin. It is necessary to take into account not so much the species, but the strain affiliation of isolates of Corynebacterium spp., since among the representatives of one species of non-diphtheria corynebacteria (for example, C. pseudodiphtheriticum), colonizing the respiratory tract, there may be strains that can exhibit not only pathogenic properties, but also probiotic activity. Microbiological diagnostics is based on their quantitative determination in biological material, phenotypic (culture study, test systems for biochemical identification, Vitek 2 automated systems) and genotypic (16SpRNA gene sequencing and rpoB) methods. It is possible to use mass spectrometric analysis (MALDI-ToF-MS). The greatest activity against Corynebacterium spp. in vitro studies preserve vancomycin, teicoplanin, and linezolid. Successful therapy with at least two of the following antimicrobial agents (AMP) has been reported: vancomycin, rifampicin, linezolid, and daptomycin. The sensitivity of isolates of Corynebacterium spp. to AMP is not related to the species, but is due to strain differences, and therefore it is necessary to test each isolated strain. Continuous monitoring of the sensitivity of Corynebacterium spp. strains to AMP is necessary due to the observed variability of these traits. Of particular importance is the identification of multidrug-resistant isolates that are currently considered highly pathogenic. When compiling the review, the databases Scopus, Web of Science, The Cochrane Library, CyberLeninka, RSCI were used.

[Is the discipline associated with self-confidence in handling rational antibiotic prescription? : Results from the MR2 study in German hospitals]. / Ist die Fachrichtung assoziiert mit der Selbstsicherheit im Umgang mit rationaler Antibiotikaverordnung? : Ergebnisse der MR2-Studien an deutschen Kliniken.

BACKGROUND: Besides public awareness and specialist knowledge and training of physicians, their self-confidence plays a key role for clinical decision-making in the respective area. OBJECTIVE: This exploratory study investigated the influence of the discipline on differences in self-confidence in dealing with antibiotics and in the self-rated knowledge. METHODS: In 2015 the multi-institutional reconnaissance of practice with multiresistant bacteria (MR2) questionnaire containing items on antibiotic prescription and multiresistant pathogens was sent out to 1061 physicians working in departments for internal medicine, general surgery, gynecology and obstetrics and urology. In 2017 a similar MR2 survey was sent to 1268 specialist and assistant physicians in anesthesiology in Germany. Besides demographic data 4 items on self-confidence in the use of antibiotic treatment and 11 items concerning self-rated knowledge about rational antibiotic therapy and multiresistant pathogens were included in the present analysis. Logistic regression analysis, the χ2-test and the Kruskal-Wallis test were used for statistical analysis of the influence of the discipline on these items. RESULTS: The response rates were 43% (456 out of 1061) from the non-anesthetists and 56% (705 out of 1268) from the anesthetists. Of the non-anesthetists 44% and 57% of the anesthetists had had no advanced training on antibiotic stewardship during the year before the study. In the overall analysis anesthetists (mean±SD: 2.53±0.54) were significantly less self-confident about antibiotics than colleagues from other departments (internal medicine: 3.10±0.50, general surgery: 2.97±0.44, gynecology and obstetrics: 3.12±0.42 and urology: 3.15±0.44) in the unadjusted (all p<0.001) and adjusted comparison. The analysis of self-rated knowledge about rational antibiotic prescription showed similar results. Senior consultant status and advanced training in infectiology were significantly associated with self-confidence and self-rated knowledge about antibiotics. CONCLUSION: Anesthetists showed significantly less self-confidence in dealing with antibiotics than colleagues from other disciplines. Advanced training on a rational prescription of antibiotics was associated with a greater self-confidence, so that the implementation of compulsory courses on rational antibiotic stewardship in the respective residency curriculum needs to be considered.

[Etiology of severe community - acquired pneumonia in adults: results of the first Russian multicenter study].

AIM: to study the etiology of severe community - acquired pneumonia (SCAP) in adults in Russian Federation. SCAP is distinguished by high mortality and socio - economic burden. Both etiology and antimicrobial resistance are essential for appropriate antibiotic choice. MATERIALS AND METHODS: A prospective cohort study recruited adults with confirmed diagnosis of SCAP admitted to multi - word hospitals of six Russian cities in 2014-2018. Etiology was confirmed by routine culture of blood, respiratory (sputum, endotracheal aspirate or bronchoalveolar lavage) and when appropriate, autopsy samples, urinary antigen tests (L. pneumophila serogroup 1, S. pneumoniae); real - time PCR for identification of "atypical" bacterial pathogens (M. pneumoniae, C. pneumoniae, L. pneumophila) and respiratory viruses (influenza viruses A and B, parainfluenza, human metapneumovirus, etc.) was applied. RESULTS: Altogether 109 patients (60.6% male; mean age 50.8±18.0 years old) with SCAP were enrolled. Etiological agent was identified in 65.1% of patients, S. pneumoniae, rhinovirus, S. aureus and K. pneumoniae were the most commonly isolated pathogens (found in 43.7, 15.5, 14.1 and 11.3% of patients with positive results of microbiological investigations, respectively). Bacteriemia was seen in 14.6% of patients and most commonly associated with S. pneumoniae. Co - infection with 2 or more causative agents was revealed in 36.6% of cases. Combination of bacterial pathogens (mainly S. pneumoniae with S. aureus or/and Enterobacterales) prevailed - 57.7% of cases; associations of bacteria and viruses were identified in 38.5% of patients, different viruses - in one case. CONCLUSION: S. pneumoniae was the most common pathogen in adults with SCAP. A high rate of respiratory viruses (mainly rhinovirus and influenza viruses) identification both as mixt infection with bacteria and mono - infection should be taken into account.

Understanding and overcoming the pitfalls and biases of next-generation sequencing (NGS) methods for use in the routine clinical microbiological diagnostic laboratory.

Recent advancements in next-generation sequencing (NGS) have provided the foundation for modern studies into the composition of microbial communities. The use of these NGS methods allows for the detection and identification of ('difficult-to-culture') microorganisms using a culture-independent strategy. In the field of routine clinical diagnostics however, the application of NGS is currently limited to microbial strain typing for epidemiological purposes only, even though the implementation of NGS for microbial community analysis may yield clinically important information. This lack of NGS implementation is due to many different factors, including issues relating to NGS method standardization and result reproducibility. In this review article, the authors provide a general introduction to the most widely used NGS methods currently available (i.e., targeted amplicon sequencing and shotgun metagenomics) and the strengths and weaknesses of each method is discussed. The focus of the publication then shifts toward 16S rRNA gene NGS methods, which are currently the most cost-effective and widely used NGS methods for research purposes, and are therefore more likely to be successfully implemented into routine clinical diagnostics in the short term. In this respect, the experimental pitfalls and biases created at each step of the 16S rRNA gene NGS workflow are explained, as well as their potential solutions. Finally, a novel diagnostic microbiota profiling platform ('MYcrobiota') is introduced, which was developed by the authors by taking into consideration the pitfalls, biases, and solutions explained in this article. The development of the MYcrobiota, and future NGS methodologies, will help pave the way toward the successful implementation of NGS methodologies into routine clinical diagnostics.

Rational application of antibiotics-The influence of anaesthetists' gender on self-confidence and knowledge.

BACKGROUND: High rates of multiresistant pathogens require detailed knowledge about rational utilization of antibiotics. Many physicians consider themselves uncertain about the interpretation of microbiological diagnostics. We examined whether self-confidence, self-rated knowledge, and objective knowledge regarding the use of antibiotics are associated with gender. METHODS: For this survey study, in 2017, anaesthesiologists and residents of 16 anaesthetic departments in Germany were asked to complete the Multiinstitutional Reconnaissance of practice with Multiresistant bacteria (MR2) survey. It consists of 55 items evaluating self-confidence regarding the practical use of antibiotics (n = 6), self-rated theoretical knowledge (n = 16), and objective knowledge (n = 5). Their answers to these items in relation to their gender were analysed using Chi-square, Kruskal-Wallis-H-Tests, and unadjusted as well as adjusted logistic regression models. RESULTS: Six hundred eighty-four (response rate: 53.9 %) questionnaires were returned and were available for analysis. Female doctors (35.5 %) felt less self-confident (P < 0.001). Self-rated knowledge differed in overall mean (P = 0.014) and the unadjusted (odds ratio [OR]: 0.55; P = 0.013) but not in the adjusted logistic regression (OR: 0.84; P = 0.525). Objective knowledge differed after pooling questions (61.2% correct answers vs 65.4%, P = 0.01) but not with respect to single items and the adjusted logistic regression (OR: 0.83, P = 0.356). CONCLUSION: Less self-confidence and a lower self-rated knowledge were found in female anaesthetists; this is consistent to the gender phenomena observed by other researchers. Nevertheless, between the 2 groups objective knowledge did not differ significantly in any item.

Persistence of Porphyromonas gingivalis is a negative predictor in patients with moderate to severe periodontitis after nonsurgical periodontal therapy.

OBJECTIVES: The aim of this study was to evaluate the quality of prediction for stable results after nonsurgical periodontal therapy by several microbiological variables of the subgingival biofilm and biomarkers of gingival crevicular fluid or oral lavage. MATERIAL AND METHODS: Forty-six individuals with moderate or severe chronic periodontitis receiving nonsurgical periodontal therapy were monitored for clinical variables, selected microorganisms, and biomarkers at baseline and 3 and 6 months thereafter. Logistic regression analysis and general linear model (GLM) were applied for analysis of variance and covariance. RESULTS: At 6 months, 20 patients showed a high response (HR) to treatment (at least 60 % of reduction of numbers of sites with PD >4 mm), whereas 26 did not (low response, LR). All clinical variables were significantly improved at 3 and 6 months within each group (p < 0.001, each compared with baseline). Modeling the impact of Porphyromonas gingivalis, Treponema denticola, and median of MMP-8 on to the response to treatment as continuous variables by GLM showed a significant influence of these variables (p = 0.045) with the strongest influence of P. gingivalis (p = 0.012) followed by T. denticola (p = 0.045) and no association with MMP-8 (p = 0.982). Samples tested positively for P. gingivalis decreased only in HR (3 months: p = 0.003; 6 months: p = 0.002). Calprotectin levels in GCF were lower in the HR group compared with the LR group at 3 months (p = 0.008) and at 6 months (p = 0.018). CONCLUSION: Persistence of P. gingivalis combined with a high GCF level of calprotectin may have a negative predictive value on response to periodontal therapy. CLINICAL RELEVANCE: Microbiological diagnostics for P. gingivalis before and 3 months after SRP may have a predictive value on response to periodontal therapy. The combination with MMP-8 in oral lavage or preferably calprotectin in GCF might give additional information.

Improving Diagnostic of Pulmonary Tuberculosis in HIV Patients by Bronchoscopy: A Cross Sectional Study.

BACKGROUND: diagnostic of pulmonary TB in HIV patients is a problem due to non specific clinical features, or radiological appearance. HIV patients with CD4≤200 cells/mL infected with M. tuberculosis have less capacity in containing M. tuberculosis, developing granulomas, casseous necrosis, or cavities. This condition is caused by weakend inflammatory which later reduced sputum production and may cause false negative result. This study aimed to assess differences in the positivity level of acid fast bacilli (AFB) and cultures of M. tuberculosis from non-bronchoscopic sputum (spontaneous and induced sputum) compared to bronchoscopic sputum (bronchoalveolar lavage) in HIV positive patients suspected pulmonary tuberculosis with CD4<200 cells/µL. METHODS: this cross sectional study was conducted in adult HIV patients treated in Hasan Sadikin Hospital with CD4≤200 cells/µL suspected with pulmonary tuberculosis by using paired comparative analytic test. All patients expelled sputum spontaneously or with sputum induction on the first day. On the next day, bronchoalveolar lavage (BAL) was performed. The two samples obtained from two methods were examined by AFB examination with staining Ziehl Neelsen (ZN) and cultured of M. tuberculosis on solid media Ogawa on all patients. Positivity, sensitivity and increased sensitivity of AFB and culture of M. tuberculosis in the non bronchoscopic and bronchoscopic groups were compared. RESULTS: there were differences in the positivity level of AFB with ZN staining between non-bronchoscopic and bronchoscopic groups which were 7/40 (17.5%) vs 20/40 (50.0%) (p<0.001). The differences between the cultures of non-bronchoscopic and bronchoscopic groups were 16/40 (40.0%) vs 23/40 (57.5%) (p=0.039). Bronchoscopic sputum increased the positivity level of the ZN AFB examination by 32.5% (from 17.5% to 50.0%) as well as on culture examination by 17.5% (from 40.0% to 57.5%). CONCLUSION: Bronchoalveolar lavage can improve the positivity level of smears and cultures in patients suspected of pulmonary TB in HIV patients with CD4<200 cells/µL.

Fast and accurate prediction of positive and negative urine cultures by flow cytometry.

BACKGROUND: Urinary tract infection (UTI) is a widespread infectious disease in humans. Urine culture, a huge workload in the microbiology laboratory, is still the standard diagnostic test for UTI, but most of the cultures are negative. A reliable screening method could reduce unnecessary cultures and quicken reporting of negative results. METHODS: We evaluated the usefulness of a flow cytometry (FC) screening method in the prediction of positive urine culture to reduce the number of urine cultures. The urine specimens sent to the laboratory for culture were tested with the flow cytometer Accuri C6. FC bacterial counts were compared to standard urine culture results to assess the best cut-off values. RESULTS: Two hundred nine urine samples were included, of which 79 (37.8 %) were culture positive. On comparing the culture and the FC data in the ROC curve, the FC bacterial counts of ≥10(6) bacteria/mL provided a reliable screening for bacteriuria with a sensitivity and specificity of 99 and 58 %, respectively. All negative FC results (<10(6) bacteria/mL) showed a negative predictive value of 99 % with a negative likelihood ratio of 0.02. The FC bacterial counts of ≥10(8)/mL showed a positive predictive value of 99 % with a positive likelihood ratio of 60.9. CONCLUSIONS: Counting bacteria in human urine samples by the FC is a fast, accurate and cost-effective screening method for bacteriuria. Our results showed that FC is able to rule out UTI, which can lead to a substantial reduction (36 %) of urine cultures. It also demonstrated that this method predicts positive cultures accurately.

Dutch dairy farmers' need for microbiological mastitis diagnostics.

Although several microbiological mastitis diagnostic tools are currently available, dairy farmers rarely use them to base treatment decisions on. In this study, we conducted a telephone interview among 195 randomly selected Dutch dairy farmers to determine their current use of and their need for microbiological diagnostics for clinical mastitis (CM), subclinical mastitis (SCM), and dry-cow treatment (DCT), followed by the test characteristics they consider important. A structured questionnaire was used, based on face-to-face interviews previously held with other farmers. The answers were registered in a database and analyzed using descriptive statistics and univariable and multivariable models. Antimicrobial treatment decisions for CM, SCM, and DCT were mainly based on clinical signs and somatic cell count. In case of CM, 34% of farmers indicated that they currently submit milk samples for bacteriological culture (BC). This would increase to 71% if an on-farm test resulting in treatment advice within 12 h were available. For SCM, use would increase from 22 to 55%, and for DCT, from 7 to 34%, if the same 12-h test were available. For CM and DCT, the preferred test outcome was advice on which antibiotic to use, according to 58 and 15% of the farmers, respectively. For SCM, the preferred test outcome was the causative bacterium for 38% of the farmers. Farmers who currently submit CM milk samples for BC were 13.1 times more likely to indicate, as the preferred test outcome, advice on which antibiotic to use, compared with farmers who do not currently submit CM milk samples for BC. Fourteen percent of the farmers indicated not being interested at all in microbiological mastitis diagnostics for CM. For SCM and DCT, 27 and 55%, respectively, were not interested in microbiological mastitis diagnostics. Regarding test characteristics that farmers considered important, reliability was most often indicated (44-51% of the farmers). Additionally, a preferred time-to-result of ≤8 h for CM and ≤20 to 24 h for SCM and DCT and ≤7% false test outcomes were indicated as desired characteristics of microbiological mastitis diagnostics. Overall, a need seems to exist for microbiological mastitis diagnostic tests among Dutch dairy farmers, specifically for CM, and resulting in a treatment advice. The availability of a reliable diagnostic test, with a suitable time-to-result, will likely increase the use of microbiological mastitis diagnostics and eventually optimize antibiotic usage.

Adherence to Antibiotic Prescription Guidelines in Four Community Hospitals in Germany.

This retrospective study aimed to assess and compare guideline adherence and treatment costs in the management of urinary tract infections (UTIs) and bloodstream infections (BSIs) in German tertiary hospitals from January 2019 to December 2020. The study analyzed 586 patient records, with 65% diagnosed with UTIs and 35% with BSIs. Antibiotic treatment was given to 98% of patients, but only 65% received microbiological diagnostics. Bacterial growth was observed in 86% of patients with cultures taken, with Escherichia coli being the leading pathogen. The treatment was intravenous in 63% of cases, with Ceftriaxone as the leading antibiotic agent. The guideline adherence was found to be low, at 33%. Multivariable logistic regression analysis revealed that patients with urogenital risk factors (OR = 1.589; p < 0.001) and increasing age (OR = 1.01; p = 0.007) were significantly more likely to receive guideline-concordant treatment for UTIs and BSIs. Additionally, complicating factors such as diabetes and renal dysfunction were associated with higher adherence rates, underscoring the importance of targeted antibiotic stewardship interventions.

New variant strain of Streptococcus canis with Lancefield group C isolated from canine otitis externa.

Every basic course in microbiology teaches us, Streptococcus canis always tests positive for Lancefield group G. Surprisingly, we identified a strain of S. canis with Lancefield group C, cultured from a dog with otitis externa after lateral ear canal resection. Whole genome sequencing data and analysis points towards a horizontal gene transfer event between S. canis and S. dysgalactiae. Although these species are closely related, gene transfer in this region of the genome of S. canis has not been described before. The value of technologies as MALDI-TOF MS and sequencing in microbiological diagnostics will grow as more diverse streptococci arise that do not always conform anymore to the classical Lancefield group typing.

Bloodstream Infections by Pantoea Species: Clinical and Microbiological Findings from a Retrospective Study, Italy, 2018-2023.

(1) Background: The widespread use of MALDI-TOF coupled to mass spectrometry has improved diagnostic accuracy by identifying uncommon bacteria. Among Enterobacterales, Pantoea species have been seen to be implicated in several human infections, but their clinical and microbiological framework is currently based on a few anecdotal reports. (2) Methods: We conducted this five-year (2018-2023) single-center study aimed at investigating the prevalence and clinical and microbiological findings of Pantoea species bloodstream infections. (3) Results: Among the 4996 bloodstream infection Gram-negative isolates collected during the study period, Pantoea species accounted for 0.4% (n = 19) of isolates from 19 different patients, 5 of them being pediatric cases. Among Pantoea species isolates, P. agglomerans was the most frequently detected (45%; n = 9) followed by P. eucrina (30%; n = 6) and P. septica (15%; n = 3). Malignancy (35.7%) in adults and malignancy (40%) and cerebrovascular disease following meconium aspiration (40%) in pediatric patients as comorbidities and shivering and/or fever following parenteral infusion (36.8%) as a symptom/sign of Pantoea species bloodstream infection onset were the most frequently observed clinical features. Among adults, primary bloodstream infection was the most frequent (50%), whereas among pediatric patients, the most commonly identified sources of infection were catheter-related (40%) and the respiratory tract (40%). Overall, Pantoea species bloodstream infection isolates displayed high susceptibility to all the antibiotics except for ampicillin (63.2%), fosfomycin (73.7%), and piperacillin/tazobactam (84.2%). Targeted antibiotic treatment was prescribed as monotherapy for adults (71.4%) and combination therapy for pediatric patients (60%). The most prescribed antibiotic regimens were piperacillin/tazobactam (21.4%) in adults and meropenem- (40%) and aminoglycoside-containing (40%) antibiotics in pediatric patients. The overall 28-day all-cause mortality rate was 5.3% (n = 1). (4) Conclusions: The prevalence and 28-day mortality rate of Pantoea species bloodstream infections were low. The prescription of targeted therapy including broad-spectrum antibiotics could indicate an underestimation of the specific involvement of the Pantoea species in the onset of the disease, warranting further studies defining their pathogenic potential.

Trends from the Last Decade with Nontuberculous Mycobacteria Lung Disease (NTM-LD): Clinicians' Perspectives in Regional Center of Pulmonology in Bydgoszcz, Poland.

BACKGROUND: Nontuberculous mycobacteria (NTM) are the cause of chronic lung disease called NTM lung disease (NTM-LD). There are about 180 known species of NTM. Nowadays the number of NTM-LD is increasing. OBJECTIVE: To evaluate the clinical significance of NTM isolated from specimens and assess the frequency and clinical relevance of isolation of NTM in the Regional Center of Pulmonology in Bydgoszcz, hospital of Northern Poland. DESIGN: Clinical, radiological, and microbiological data were collected from all patients from whom NTM was isolated between 2013 and 2022. Data were reviewed retrospectively. Diagnostic criteria for NTM-LD published by the American Thoracic Society (ATS) were used to determine clinical relevance. MATERIAL AND METHODS: The study comprised 81,985 clinical specimens submitted for mycobacterial culture in the Department of Microbiology at the Regional Center of Pulmonology in Bydgoszcz between 2013 and 2022. Clinical specimens were processed according to the standard procedure in mycobacteria laboratories in Poland. NTM strains were identified using analysis of mycolic acids by chromatography as well as GenoType NTM-DR, GenoType Mycobacterium AS, and GenoType Mycobacterium CM. RESULTS: There were 395 patients with NTM strains between 2013 and 2022. Out of them, 149 cases met the diagnostic criteria of NTM-LD and were classified as definite cases. M. kansasii (n = 77) was the most common species in the group (51.68%), followed by M. avium complex (n = 46). Patients with NTM-LD were 22-88 years old (median age was 60 years). There were 81 men and 68 women. The most common symptoms were cough, hemoptysis, and fever. Radiological X-ray images were dominated by infiltrative lesions in the upper and middle lobe of the right lung with cavities; the changes were in the upper lobe of the left lung and on both sides of the chest. They were smokers in 61%. The most common concomitant diseases were chronic obstructive pulmonary disease (COPD), diabetes mellitus, pulmonary carcinoma, and human immunodeficiency virus (HIV) infection, and other immunodeficiencies. The most common treatment was isoniazid, ethambutol, rifampicin, and ofloxacin for 18 months with a minimum of 12 months of culture negativity. CONCLUSIONS: NTM-LD infections are present with other pulmonary illnesses and extrapulmonary diseases and may be connected to primary immunologic deficiencies. These diseases concern patients of all ages and have various clinical manifestations. M. kansasii and MAC are the most prevalent NTM isolates among respiratory samples in Northern Poland. In addition, an increase in MAC and a decrease in M. kansasii both in cultivation and the cause of NTM-LD were reported.

Knowledge, Attitude and Practice Regarding Staphylococcus pettenkoferi.

Staphylococcus pettenkoferi is a coagulase-negative staphylococcus, first described in 2002. Using medical databases, i.e., Scopus, Web of Science, Pubmed, and Embase, we identified and analysed research, reports, and opinions dealing with S. pettenkoferi. Published data allow us to conclude that S. pettenkoferi is a human commensal, opportunistic bacterium and may be isolated from the environment and animals. The involvement of S. pettenkoferi in bloodstream infection and osteomyelitis has been described, but its clinical relevance is not fully understood, so far. This work summarizes knowledge about S. pettenkoferi and reveals the difficulties and rules for interpreting the results of microbiological tests, when S. pettenkoferi has been identified in the blood sample. Clinical and laboratory criteria, recommended by Centers for Disease Control and Prevention (CDC) and the third international consensus definitions of sepsis and septic shock (Sepsis-3), are important to determine whether the presence of bacteria in the sample is a consequence of an infection, contamination from the environment, or translocation of the bacteria outside the place of its natural existence. The precise identification of bacteria from the blood sample and recognizing the true bacteraemia are critical to implement the appropriate procedures and make decisions concerning the patient's medical care.

From NTM (Nontuberculous mycobacterium) to Gordonia bronchialis-A Diagnostic Challenge in the COPD Patient.

In patients with chronic obstructive pulmonary disease, respiratory infections are of various aetiology, predominantly viral and bacterial. However, due to structural and immunological changes within the respiratory system, such patients are also prone to mycobacterial and other relatively rare infections. We present the 70-year old male patient with chronic obstructive pulmonary disease (COPD) and coexisting bronchial asthma, diagnosed due to cough with purulent sputum expectoration lasting over three months. The first microbiological investigation of the sputum sample revealed the growth of mycobacteria. The identification test based on protein MPT64 production indicated an organism belonging to NTM (nontuberculous mycobacterium). However, further species identification by genetic testing verified the obtained culture as not belonging to the Mycobacterium genus. Based on observed morphology, the new characterisation identified an aerobic actinomycete, possibly a Nocardia spp. The isolated strain was recultured on standard microbiological media. The growth of colonies was observed on Columbia blood agar plates and solid Löewenstein-Jensen medium. The Gram and Zhiel-Nielsen stains revealed the presence of Gram-positive acid-fast bacilli. The extraction protocol and identification were performed in two repetitions; the result was G. bronchialis, with a confidence value of 99% and 95%, respectively. The gene sequencing method was applied to confirm the species affiliation of this isolate. The resulting sequence was checked against the 16S ribosomal RNA sequences database (Bacteria and Archaea). The ten best results indicated the genus Gordonia (99.04-100%) and 100% similarity of the 16S sequenced region was demonstrated for Gordonia bronchialis. The case described indicates that the correct interpretation of microbiological test results requires the use of advanced microbiology diagnosis techniques, including molecular identification of gene sequences. From a clinical point of view, Gordonia bronchialis infection or colonization may present a mild course, with no febrile episodes and no significant patient status deterioration and thus, it may remain undiagnosed more often than expected.

Hospital Urinary Tract Infections in Healthcare Units on the Example of Mazovian Specialist Hospital Ltd.

Microbiological diagnostics is of great importance in limiting the spread of nosocomial infections. The information on etiological agents of infections and their susceptibility to antibiotics enables a quick response in the case of a suspected epidemic outbreak. The aim of this study is to analyze the incidence of nosocomial urinary tract infections among patients hospitalized in hospital wards over a period of 2 years and to determine the predominant etiological agent depending on the method of clinical specimen collection. Data from the Mazovian Specialist Hospital (MSH) in Radom constitute the material for the preparation of this study. Urine was collected using two methods. The first one was the method of collecting urine from the central stream, while the second method was urine collected from patients with a urinary catheter in place. The statistical calculations were conducted using the statistical software. Based on hospital data, it was shown that 5,870 urine tests were performed during the period under review, of which 2,070 were positive. The number of positive results in 2021 decreased by 2.84% compared to that in 2020. On the basis of the statistical analysis, differences in the occurrence of multiple strains were observed between catheter-based and midstream urine collection. Differences were observed especially for Acinetobacter baumannii, Candida albicans, Escherichia coli, and Pseudomonas aeruginosa. A. baumannii, C. albicans, and P. aeruginosa were significantly more frequently found in urine samples collected through the catheter than from the midstream. Furthermore, E. coli (51.56%) and Enterococcus species (25.46%) were more frequent when collected from the middle stream than when urine was collected through a catheter. However, for the strain K. pneumoniae, the results were comparable when urine was collected from catheterized patients (13.83%) and from midstream (13.35%). Urinary tract infection among hospitalized patients of the Mazovian Specialist Hospital in Radom was diagnosed quite frequently. In 2021, 32 more urine cultures were performed than in 2020. In the analyzed period, among all ordered urine cultures, 35.27% of samples were positive.

Phenotypic Variants of Bacterial Colonies in Microbiological Diagnostics: How Often Are They Indicative of Differing Antimicrobial Susceptibility Patterns?

Phenotypic variants (PV) are colonies of the same species in the same specimen with different morphological features. It is controversial whether antimicrobial susceptibility testing (AST) should be done for all PV. The objectives of this study were to quantify the proportion of differing antimicrobial susceptibility patterns (dASP) among PV and to identify species and antimicrobial compounds that are mostly affected. All PV from routine diagnostics (University Hospital Münster, Germany; 1 September 2019 to 31 August 2020) were subjected to species identification (matrix-assisted laser desorption ionization-time of flight mass spectrometry [MALDI-TOF MS]) and AST (Vitek 2). To assess the dASP, only antimicrobial agents were considered for which Vitek-derived MIC were available (interpreted according to the EUCAST clinical breakpoints). The categorical agreement (CA; agreement with the AST categories S [susceptible, standard dosing regimen], I [susceptible, increased exposure], R [resistant]) of the PV was calculated. The PV of Escherichia coli (n = 260), Pseudomonas aeruginosa (n = 86), Klebsiella pneumoniae (n = 47), Enterobacter cloacae complex (n = 45), and Staphylococcus aureus (n = 38) were included. The median CA was 95% (range, 80 to 100%, depending on the species). The colony characteristics (e.g., form/size, color, margin, hemolysis) were not indicative for dASP. PV showed a high categorical agreement in the AST categories. This observation supports a test strategy to perform AST for only one colony of PV. IMPORTANCE Phenotypic variants of bacteria are frequent in routine diagnostics and can display differing antimicrobial susceptibility patterns. We found that the likelihood of different antimicrobial susceptibility is low among PV. To save laboratory resources, only one isolate per PV could be tested to guide the antimicrobial treatment of patients.