European Association of Urology Guidelines on Urological Infections: Summary of the 2024 Guidelines.

BACKGROUND AND OBJECTIVE: Urological infections significantly impact the wellbeing and quality of life of individuals owing to their widespread occurrence and diverse clinical manifestations. The objective of the guidelines panel was to provide evidence-based guidance on the diagnosis, treatment, and prevention of urinary tract infections (UTIs) and male accessory-gland infections, while addressing crucial public health aspects related to infection control and antimicrobial stewardship. METHODS: For the 2024 guidelines on urological infections, new and relevant evidence was identified, collated, and appraised via a structured assessment of the literature. Databases searched included Medline, EMBASE, and the Cochrane Libraries. Recommendations within the guidelines were developed by the panel to prioritise clinically important care decisions. The strength of each recommendation was determined according to a balance between desirable and undesirable consequences of alternative management strategies, the quality of the evidence (including the certainty of estimates), and the nature and variability of patient values and preferences. KEY FINDINGS AND LIMITATIONS: Key recommendations emphasise the importance of a thorough medical history and physical examination for patients with urological infections. The guidelines stress the role of antimicrobial stewardship to combat the rising threat of antimicrobial resistance, providing recommendations for antibiotic selection, dosing, and duration on the basis of the latest evidence. CONCLUSIONS AND CLINICAL IMPLICATIONS: This overview of the 2024 EAU guidelines offers valuable insights into managing urological infections and are designed for effective integration into clinical practice. PATIENT SUMMARY: The European Association of Urology has issued an updated guideline on urological infections. The guidelines provide recommendations for diagnosis, treatment, and prevention, with a particular focus on minimising antibiotic use because of the increasing global threat of antimicrobial resistance.

The Diagnosis, Treatment, and Prevention of Recurrent Urinary Tract Infection.

BACKGROUND: Urinary tract infection has a one-year prevalence of 11% in women and ranges among the most common reasons for consulting a primary care physician and for receiving a prescription for antibiotics. In the case of recurrent urinary tract infection (rUTI), there are questions about the further work-up, treatment, and preventive measures. METHODS: The systematic literature search performed for the update of the German clinical practice guideline on uncomplicated urinary tract infection (043-044) (up to February 2022) was supplemented with a selective search for clinical trials (up to August 2023). RESULTS: Urine culture and ultrasonography are reasonable steps in the diagnostic evaluation of rUTI. Further invasive testing is suggested for men but is not routinely indicated for women. Antibiotics are among the most effective preventive measures (risk ratio [RR] 0.15, 95% confidence interval [0.1; 0.3]) but carry a high risk of side effects. Non-antibiotic preparations such as cranberry juice (RR 0.74 [0.5; 0.99]), mannose (RR 0.23 [0.14; 0.37]), and vaginal estrogen (RR, 0.42 [0.30; 0.59]) can also reduce the infection rate, with a low risk of side effects. Increased daily fluid intake has been shown to lower infection rates in the short term (odds ratio [OR] 0.13 [0.07; 0.25]); the use of hygienically advisable wiping techniques after passing stool or urine has been little studied but can be implemented with no risk. CONCLUSION: rUTI poses a challenge for the treating physician. The measures to be taken must be considered on an individual basis. Vulnerable groups, such as older patients, need special attention.

The EFLM European Urinalysis Guideline 2023.

BACKGROUND: The EFLM Task and Finish Group Urinalysis has updated the ECLM European Urinalysis Guidelines (2000) on urinalysis and urine bacterial culture, to improve accuracy of these examinations in European clinical laboratories, and to support diagnostic industry to develop new technologies. RECOMMENDATIONS: Graded recommendations were built in the following areas. MEDICAL NEEDS AND TEST REQUISITION: Strategies of urine testing are described to patients with complicated or uncomplicated urinary tract infection (UTI), and high or low-risk to kidney disease. SPECIMEN COLLECTION: Patient preparation, and urine collection are supported with two quality indicators: contamination rate (cultures), and density of urine (chemistry, particles). CHEMISTRY: Measurements of both urine albumin and α1-microglobulin are recommended for sensitive detection of kidney disease in high-risk patients. Performance specifications are given for urine protein measurements and quality control of multiproperty strip tests. PARTICLES: Procedures for microscopy are reviewed for diagnostic urine particles, including urine bacteria. Technologies in automated particle counting and visual microscopy are updated with advice how to verify new instruments with the reference microscopy. BACTERIOLOGY: Chromogenic agar is recommended as primary medium in urine cultures. Limits of significant growth are reviewed, with an optimised workflow for routine specimens, using leukocyturia to reduce less important antimicrobial susceptibility testing. Automation in bacteriology is encouraged to shorten turn-around times. Matrix assisted laser desorption ionization time-of-flight mass spectrometry is applicable for rapid identification of uropathogens. Aerococcus urinae, A. sanguinicola and Actinotignum schaalii are taken into the list of uropathogens. A reference examination procedure was developed for urine bacterial cultures.

Genitourinary Tuberculosis: A Brief Manual for Urologists on Diagnosis and Treatment from the European Association of Urology Urological Infections Panel.

Although tuberculosis (TB) ranks among the most frequent infectious diseases worldwide, one of its extrapulmonary (EP) manifestations, genitourinary (GU) TB, is often underestimated by urologists, particularly in areas such as Europe where TB is not endemic. The aim of this review is to give urologists a concise overview of GUTB as a supplement to the more comprehensive European Association of Urology 2023 update on urological infections guidelines. EPTB can develop in 16% of TB cases. GUTB accounts for 4.6% of EPTB and is often asymptomatic or nonspecific, so it can be confused with other urogenital diseases. GUTB can be highly destructive, leading to failure of urogenital organs. Diagnosis is via microbiological, molecular, and histological testing for urine, genital secretions, or genitourinary tissue, supported by imaging. A 6-mo combinational medical regimen is the first-line treatment for GUTB. However, surgical interventions are also frequently required for the treatment of GUTB complications. Therefore, it is important to keep GUTB in mind for differential diagnosis. PATIENT SUMMARY: We reviewed scientific studies on the occurrence, diagnosis, and treatment of tuberculosis in the genitourinary tract. Our aim is to raise awareness among urologists from countries where this disease does not occur frequently, as urogenital tuberculosis can occur without any symptoms or with unspecific symptoms that can be confused with other diseases.

A retrospective evaluation of the Euroarray STI-11 multiplex system for the detection of eight STI causing agents.

With an incidence of more than > 1,000,000/day, sexually transmitted diseases remain a major challenge for health care systems worldwide. To reduce disease burden, complications, and spread, rapid diagnosis permitting early therapy is pivotal. The range of pathogens is wide and co-infections are common. This complicates pre-analytics, which are based on different laboratory techniques with potentially long turnaround times, e.g., cultivation and multistep serologies. Multiplex PCR provides the opportunity to overcome these limitations. In this study, we evaluated a novel assay, the Euroarray STI-11 microarray (EA; Euroimmun Medizinische Labordiagnostika), for the detection of eight obligate or facultative pathogens. Three-hundred-thirteen clinical specimens, which had been tested and pre-characterized for STI causing agents as part of routine diagnostics, were used as cases and controls in this retrospective study. The EA detected 34/44 Chlamydia trachomatis, 48/50 HSV-1, 50/50 HSV-2, 48/48 Mycoplasma hominis, 45/47 Neisseria gonorrhoeae, 9/11 Treponema pallidum, 46/46 Ureaplasma parvum, and 49/49 Ureaplasma urealyticum infections, respectively. 293 samples were EA positive, with polymicrobial infections (positive for two to six microbial or viral agents) detected in 130/293 cases. Specificities were 100% in the respective control groups (n = 18-48 depending on targeted pathogen) except for N. gonorrhoeae (25/26) and U. urealyticum (44/45). The broad spectrum of obligate and facultative pathogens targeted by the EA makes it a valuable tool in the setting of STI diagnostics and surveillance. The test has the potential to diagnose diseases neglected or overlooked in routine clinical practice. Besides a low sensitivity for C. trachomatis, the EA demonstrated high performance for all analyzed parameters. Further studies are warranted in order to capture a larger variety of the tested pathogens.

Rapid Antibiotic Susceptibility Testing of Gram-Negative Bacteria Directly from Urine Samples of UTI Patients Using MALDI-TOF MS.

Urinary tract infections (UTIs) are one of the most common human infections and are most often caused by Gram-negative bacteria such as Escherichia coli. In view of the increasing number of antibiotic-resistant isolates, rapidly initiating effective antibiotic therapy is essential. Therefore, a faster antibiotic susceptibility test (AST) is desirable. The MALDI-TOF MS-based phenotypic antibiotic susceptibility test (MALDI AST) has been used in blood culture diagnostics to rapidly detect antibiotic susceptibility. This study demonstrates for the first time that MALDI AST can be used to rapidly determine antibiotic susceptibility in UTIs directly from patients' urine samples. MALDI-TOF MS enables the rapid identification and AST of Gram-negative UTIs within 4.5 h of receiving urine samples. Six urinary tract infection antibiotics, including ciprofloxacin, cotrimoxazole, fosfomycin, meropenem, cefuroxime, and nitrofurantoin, were analyzed and compared with conventional culture-based AST methods. A total of 105 urine samples from UTI patients contained bacterial isolates for MALDI AST. The combination of ID and AST by MALDI-TOF allowed us to interpret the result according to EUCAST guidelines. An overall agreement of 94.7% was found between MALDI AST and conventional AST for the urinary tract pathogens tested.

Quantitative proteomic analysis of cerebrospinal fluid from patients with idiopathic facial nerve palsy.

BACKGROUND AND PURPOSE: Idiopathic facial palsy (IFP) accounts for over 60% of peripheral facial palsy (FP) cases. The cause of IFP remains to be determined. Possible etiologies are nerve swelling due to inflammation and/or viral infection. In this study, we applied an integrative mass spectrometry approach to identify possibly altered protein patterns in the cerebrospinal fluid (CSF) of IFP patients. METHODS: We obtained CSF samples from 34 patients with FP. In four patients, varicella-zoster virus was the cause (VZV-FP). Among the 30 patients diagnosed with IFP, 17 had normal CSF parameters, five had slightly elevated CSF cell counts and normal or elevated CSF protein, and eight had normal CSF cell counts but elevated CSF protein. Five patients with primary headache served as controls. All samples were tested for viral pathogens by PCR and subjected to liquid chromatography tandem mass spectrometry and bioinformatics analysis and multiplex cytokine/chemokine arrays. RESULTS: All CSF samples, except those from VZV-FP patients, were negative for all tested pathogens. The protein composition of CSF samples from IFP patients with normal CSF was comparable to controls. IFP patients with elevated CSF protein showed dysregulated proteins involved in inflammatory pathways, findings which were similar to those in VZV-FP patients. Multiplex analysis revealed similarly elevated cytokine levels in the CSF of IFP patients with elevated CSF protein and VZV-FP. CONCLUSIONS: Our study revealed a subgroup of IFP patients with elevated CSF protein that showed upregulated inflammatory pathways, suggesting an inflammatory/infectious cause. However, no evidence for an inflammatory cause was found in IFP patients with normal CSF.

Cerebrospinal fluid analysis in emergency patients with suspected infection of the central nervous system.

BACKGROUND AND PURPOSE: Meningitis and encephalitis are potentially life-threatening diseases that require fast and accurate diagnostics and therapy. The value of polymerase chain reaction (PCR) multiplex testing in clinical practice is still a matter of debate. This study aims to evaluate its benefits and limitations in emergency patients. METHODS: We assessed the value of a meningoencephalitis PCR array in the clinical routine of an emergency department. RESULTS: Of 1578 emergency patients who received a lumbar puncture, 43% received it for a clinically suspected central nervous system (CNS) infection. After initial workup for cerebrospinal fluid (CSF) cell count, protein and glucose, a CNS infection was still considered likely in 307 patients. In these patients, further microbiologic workup was performed. A total of 230 samples were examined by PCR and a pathogen was detected in 66 of these samples. In the case of a positive microbiologic result, a comparison between PCR array and standard method was available for 59 samples, which demonstrated an overcall agreement of 80% (n = 47/59). Of interest, exclusively array-positive results were observed for patients with meningitis found to be positive for Streptococcus pneumoniae; four out of five patients had been treated with antibiotics before the lumbar puncture. In samples with normal CSF cell count only two positive array results were obtained, both for human herpesvirus 6, and these were not clinically relevant. CONCLUSION: Our data suggest that the array substantially contributes to a detection of pathogens in patients with suspected CNS infection and seems of particular interest in patients with acute bacterial meningitis under empiric antibiotic treatment. In CSF samples with normal cell count, it might be dispensable.

Performance of Multiplex PCR and ß-1,3-D-Glucan Testing for the Diagnosis of Candidemia.

Bloodstream infections caused by Candida yeasts (candidemia) are associated with high morbidity and mortality. Diagnosis remains challenging, with the current gold standard­isolation from blood culture (BC)­being limited by low sensitivity and long turnaround time. This study evaluated the performance of two nonculture methods: PCR and ß-1,3-D-glucan (BDG) testing. The sera of 103 patients with BC-proven candidemia and of 46 controls were analyzed with the Fungiplex Candida Real-Time PCR and the Wako ß-Glucan Test. The BDG assay demonstrated higher sensitivity than the multiplex PCR (58% vs. 33%). This was particularly evident in ICU patients (60% vs. 28%) and in C. albicans candidemia (57% vs. 37%). The earlier prior to BC sampling the sera were obtained, the more the PCR sensitivity decreased (46% to 18% in the periods of 0−2 and 3−5 days before BC, respectively), while BDG testing was independent of the sampling date. No positive PCR results were obtained in sera sampled more than five days before BC. Specificities were 89% for BDG and 93% for PCR testing. In conclusion, BDG testing demonstrated several advantages over PCR testing for the diagnosis of candidemia, including higher sensitivity and earlier diagnosis. However, BC remains essential, as BDG does not allow for species differentiation.

Ecological effects of selective oral decontamination on multidrug-resistance bacteria acquired in the intensive care unit: a case-control study over 5 years.

PURPOSE: This case-control study investigated the long-term evolution of multidrug-resistant bacteria (MDRB) over a 5-year period associated with the use of selective oropharyngeal decontamination (SOD) in the intensive care unit (ICU). In addition, effects on health care-associated infections and ICU mortality were analysed. METHODS: We investigated patients undergoing mechanical ventilation > 48 h in 11 adult ICUs located at 3 campuses of a university hospital. Administrative, clinical, and microbiological data which were routinely recorded electronically served as the basis. We analysed differences in the rates and incidence densities (ID, cases per 1000 patient-days) of MDRB associated with SOD use in all patients and stratified by patient origin (outpatient or inpatient). After propensity score matching, health-care infections and ICU mortality were compared. RESULTS: 5034 patients were eligible for the study. 1694 patients were not given SOD. There were no differences in the incidence density of MDRB when SOD was used, except for more vancomycin-resistant Enterococcus faecium (0.72/1000 days vs. 0.31/1000 days, p < 0.01), and fewer ESBL-producing Klebsiella pneumoniae (0.22/1000 days vs. 0.56/1000 days, p < 0.01). After propensity score matching, SOD was associated with lower incidence rates of ventilator-associated pneumonia and death in the ICU but not with ICU-acquired bacteremia or urinary tract infection. CONCLUSIONS: Comparisons of the ICU-acquired MDRB over a 5-year period revealed no differences in incidence density, except for lower rate of ESBL-producing Klebsiella pneumoniae and higher rate of vancomycin-resistant Enterococcus faecium with SOD. Incidence rates of ventilator-associated pneumonia and death in the ICU were lower in patients receiving SOD.

A Yersiniabactin-producing Klebsiella aerogenes Strain Causing an Outbreak in an Austrian Neonatal Intensive Care Unit.

BACKGROUND: Yersiniabactin, a siderophore with a high affinity to iron, has been described as a potential virulence factor in Enterobacteriaceae. Klebsiella aerogenes is a Gram-negative rod known to cause invasive infection in very low birth weight infants but is an unusual pathogen to cause outbreaks in neonatal intensive care units (NICU). METHODS: We performed a retrospective analysis of all patients colonized with K. aerogenes in our NICU from September to December 2018. Each infant with an occurrence of K. aerogenes in any microbiological culture was defined as a case. Clinical data were taken from medical charts. K. aerogenes isolates were genotyped using whole-genome sequencing combined with core genome multilocus sequencing type analysis. Yersiniabactin production was evaluated by luciferase assay. RESULTS: In total 16 patients were colonized with K. aerogenes over the 3-month period and 13 patients remained asymptomatic or developed late-onset neonatal sepsis from another pathogen. Three patients developed necrotizing enterocolitis, 2 complicated by sepsis and 1 of them died. All symptomatic patients were premature infants with low birth weight. Genetic sequencing confirmed an outbreak with the same strain, all samples expressed the high-pathogenicity island, necessary for the production of yersiniabactin. Six exemplary cases were proven to produce yersiniabactin in vitro. CONCLUSION: This is the first report of an outbreak of a yersiniabactin-producing K. aerogenes strain causing invasive infection in preterm infants. We hypothesize that, due to improved iron uptake, this strain was associated with higher virulence than non-yersiniabactin-producing strains. Extended search for virulence factors and genetic sequencing could be pivotal in the management of NICU outbreaks in the future.

Two Polyketides Intertwined in Complex Regulation: Posttranscriptional CsrA-Mediated Control of Colibactin and Yersiniabactin Synthesis in Escherichia coli.

Bacteria have to process several levels of gene regulation and coordination of interconnected regulatory networks to ensure the most adequate cellular response to specific growth conditions. Especially, expression of complex and costly fitness and pathogenicity-associated traits is coordinated and tightly regulated at multiple levels. We studied the interconnected regulation of the expression of the colibactin and yersiniabactin polyketide biosynthesis machineries, which are encoded by two pathogenicity islands found in many phylogroup B2 Escherichia coli isolates. Comparative phenotypic and genotypic analyses identified the BarA-UvrY two-component system as an important regulatory element involved in colibactin and yersiniabactin expression. The carbon storage regulator (Csr) system controls the expression of a wide range of central metabolic and virulence-associated traits. The availability of CsrA, the key translational regulator of the Csr system, depends on BarA-UvrY activity. We employed reporter gene fusions to demonstrate UvrY- and CsrA-dependent expression of the colibactin and yersiniabactin determinants and confirmed a direct interaction of CsrA with the 5' untranslated leader transcripts of representative genes of the colibactin and yersiniabactin operons by RNA electrophoretic mobility shift assays. This posttranscriptional regulation adds an additional level of complexity to control mechanisms of polyketide expression, which is also orchestrated at the level of ferric uptake regulator (Fur)-dependent regulation of transcription and phosphopantetheinyl transferase-dependent activation of polyketide biosynthesis. Our results emphasize the interconnection of iron- and primary metabolism-responsive regulation of colibactin and yersiniabactin expression by the fine-tuned action of different regulatory mechanisms in response to variable environmental signals as a prerequisite for bacterial adaptability, fitness, and pathogenicity in different habitats. IMPORTANCE Secondary metabolite expression is a widespread strategy among bacteria to improve their fitness in habitats where they constantly compete for resources with other bacteria. The production of secondary metabolites is associated with a metabolic and energetic burden. Colibactin and yersiniabactin are two polyketides, which are expressed in concert and promote the virulence of different enterobacterial pathogens. To maximize fitness, they should be expressed only in microenvironments in which they are required. Accordingly, precise regulation of colibactin and yersiniabactin expression is crucial. We show that the expression of these two polyketides is also interconnected via primary metabolism-responsive regulation at the posttranscriptional level by the CsrA RNA-binding protein. Our findings may help to optimize (over-)expression and further functional characterization of the polyketide colibactin. Additionally, this new aspect of concerted colibactin and yersiniabactin expression extends our knowledge of conditions that favor the expression of these virulence- and fitness-associated factors in different Enterobacterales members.

European Association of Urology Position Paper on the Prevention of Infectious Complications Following Prostate Biopsy.

The transperineal approach is preferred to reduce prostate biopsy (PB)-related infections. Fluoroquinolones are suspended for prophylaxis of PB in the European Union; therefore, alternative antibiotics based on local resistance, or targeted prophylaxis, in conjunction with povidone-iodine rectal preparation are recommended for transrectal PB.

Major role of iron uptake systems in the intrinsic extra-intestinal virulence of the genus Escherichia revealed by a genome-wide association study.

The genus Escherichia is composed of several species and cryptic clades, including E. coli, which behaves as a vertebrate gut commensal, but also as an opportunistic pathogen involved in both diarrheic and extra-intestinal diseases. To characterize the genetic determinants of extra-intestinal virulence within the genus, we carried out an unbiased genome-wide association study (GWAS) on 370 commensal, pathogenic and environmental strains representative of the Escherichia genus phylogenetic diversity and including E. albertii (n = 7), E. fergusonii (n = 5), Escherichia clades (n = 32) and E. coli (n = 326), tested in a mouse model of sepsis. We found that the presence of the high-pathogenicity island (HPI), a ~35 kbp gene island encoding the yersiniabactin siderophore, is highly associated with death in mice, surpassing other associated genetic factors also related to iron uptake, such as the aerobactin and the sitABCD operons. We confirmed the association in vivo by deleting key genes of the HPI in E. coli strains in two phylogenetic backgrounds. We then searched for correlations between virulence, iron capture systems and in vitro growth in a subset of E. coli strains (N = 186) previously phenotyped across growth conditions, including antibiotics and other chemical and physical stressors. We found that virulence and iron capture systems are positively correlated with growth in the presence of numerous antibiotics, probably due to co-selection of virulence and resistance. We also found negative correlations between virulence, iron uptake systems and growth in the presence of specific antibiotics (i.e. cefsulodin and tobramycin), which hints at potential "collateral sensitivities" associated with intrinsic virulence. This study points to the major role of iron capture systems in the extra-intestinal virulence of the genus Escherichia.

Calculated parenteral initial treatment of bacterial infections: Infections of the kidneys and the genito-urinary tract.

This is the eighth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. The chapter deals with the treatment of more severe infections of the kidney and the urogenital tract, including urosepsis. Recommendations for empiric and targeted antibacterial treatment are given.

In vitro efficacy of phytotherapeutics suggested for prevention and therapy of urinary tract infections.

PURPOSE: To analyse the therapeutic efficacy of various phytotherapeutics and their antimicrobial compounds with regard to strain specificity and dose dependence. METHODS: A representative strain collection of 40 uropathogenic bacteria isolated from complicated and uncomplicated urinary tract infection was subjected to various virulence assays (bacterial growth, mannose-sensitive agglutination, and motility) to determine the therapeutic impact of various compounds with antimicrobial activity. We tested proanthocyanidins (PAC), D-mannose, rosemary extract (Canephron®), and isothiocyanates (Angocin®). RESULTS: D-mannose efficiently blocked the adhesive properties of all type 1 fimbriae-positive isolates in low concentration (0.2%), but showed no bacteriostatic effect. PAC also actively blocked agglutination, but the concentration varied considerably among isolates. Escherichia coli required the highest concentration (10%), while Enterobacter cloacae responded to low concentrations (0.1%). Allyl isothiocyanates not only impaired agglutination in all tested isolates, but also had a dramatic impact on flagella-mediated motility in Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis (p < 0.001). The administration of rosemary extracts revealed a strong bacteriostatic effect in growth assays. All tested strains were strongly inhibited by the addition of 10 µg/ml or 1 µg/ml of purified rosemary extractions with the exception of Serratia marcescens. Morganella morganii responded only to 10 µg/ml. CONCLUSION: Phytotherapeutics and small-molecular compounds like mannosides have the potential to become an integral part in a multi-modal treatment concept for the treatment and prevention of urinary tract infections. Their efficiency can be optimised when strain specificities and therapeutic concentrations are taken into account.

Identification and Containment of a Cluster of Two Bacillus cereus Infections in a Neonatal Intensive Care Unit.

We report a cluster of invasive Bacillus cereus infections in a neonatal intensive care unit. We describe the clinical course of two infected patients, one of whom died of severe pneumonia after successfully being weaned from ECMO. Environmental analyses failed to yield a common source. Molecular characterization confirmed the homogeneity of both isolates. Rigorous hygiene control and adequate therapy enabled the containment of the cluster.

Whole genome sequencing suggests transmission of Corynebacterium diphtheriae-caused cutaneous diphtheria in two siblings, Germany, 2018.

In September 2018, a child who had returned from Somalia to Germany presented with cutaneous diphtheria by toxigenic Corynebacterium diphtheriae biovar mitis. The child's sibling had superinfected insect bites harbouring also toxigenic C. diphtheriae. Next generation sequencing (NGS) revealed the same strain in both patients suggesting very recent human-to-human transmission. Epidemiological and NGS data suggest that the two cutaneous diphtheria cases constitute the first outbreak by toxigenic C. diphtheriae in Germany since the 1980s.

Outbreak of Yersiniabactin-producing Klebsiella pneumoniae in a Neonatal Intensive Care Unit.

BACKGROUND: The Gram-negative bacterium Klebsiella pneumoniae is a frequent pathogen causing outbreaks in neonatal intensive care units. Some Enterobacteriaceae can acquire the ability to sequester iron from infected tissue by secretion of iron-chelating compounds such as yersiniabactin. Here we describe an outbreak and clinical management of infections because of a highly virulent yersiniabactin-producing, nonmultiresistant K. pneumoniae strain in a neonatal intensive care unit. Outbreak investigation and effectiveness assessment of multidisciplinary infection control measurements to prevent patient-to-patient transmission of highly pathogenic K. pneumoniae were undertaken. METHODS: Outbreak cases were identified by isolation of K. pneumoniae from blood or stool of infants. Clinical data were abstracted from medical charts. K. pneumoniae isolates were genotyped using whole genome sequencing, and yersiniabactin production was evaluated by luciferase assay. RESULTS: Fourteen cases were confirmed with 8 symptomatic and 6 colonized patients. Symptomatic patients were infants of extremely low gestational and chronologic age with fulminant clinical courses including necrotizing enterocolitis and sepsis. Whole genome sequencing for bacterial isolates confirmed the presence of an outbreak. All outbreak isolates produced yersiniabactin. CONCLUSIONS: Yersiniabactin-producing K. pneumoniae can display a high pathogenicity in extremely premature infants with low chronologic age. This outbreak also underlines the considerable potential of today's infection control systems for recognizing and controlling nosocomial infections in highly vulnerable populations.