Comparative epidemiology of bacteraemia in two ageing populations: Singapore and Denmark.

Burden of bacteraemia is rising due to increased average life expectancy in developed countries. This study aimed to compare the epidemiology and outcomes of bacteraemia in two similarly ageing populations with different ethnicities in Singapore and Denmark. Historical cohorts from the second largest acute-care hospital in Singapore and in the hospitals of two Danish regions included patients aged 15 and above who were admitted from 1 January 2006 to 31 December 2016 with at least 1 day of hospital stay and a pathogenic organism identified. Among 13 144 and 39 073 bacteraemia patients from Singapore and Denmark, similar 30-day mortality rates (16.5%; 20.3%), length of hospital stay (median 14 (IQR: 9-28) days; 11 (6-21)), and admission rate to ICU (15.5%; 15.6%) were observed, respectively. Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus ranked among the top four in both countries. However, Singaporeans had a higher proportion of patients with diabetes (46.8%) and renal disease (29.5%) than the Danes (28.0% and 13.7%, respectively), whilst the Danes had a higher proportion of patients with chronic pulmonary disease (18.0%) and malignancy (35.3%) than Singaporeans (9.7% and 16.2%, respectively). Our study showed that top four causative organisms and clinical outcomes were similar between the two cohorts despite pre-existing comorbidities differed.

Low protection from breakthrough SARS-CoV-2 infection and mild disease course in ocrelizumab-treated patients with multiple sclerosis after three mRNA vaccine doses.

BACKGROUND: Our study investigated the rate of breakthrough SARS-CoV-2 infection and clinical outcomes in a cohort of multiple sclerosis (MS) patients who were treated with the anti-CD20 monoclonal antibody (Ab), ocrelizumab, before first, second and third BNT162b2 mRNA vaccinations. To correlate clinical outcomes with the humoral and cellular response. METHODS: The study was a prospective non-randomised controlled multicentre trial observational study. Participants with a diagnosis of MS who were treated for at least 12 months with ocrelizumab prior to the first BNT162b2 mRNA vaccination were prospectively followed up from January 2021 to June 2022. RESULTS: Out of 54 participants, 32 (59.3%) developed a positive SARS-CoV-2 PCR test in the study period. Mild infection was observed in all infected participants. After the third vaccination, the non-infected participants had higher mean Ab levels compared to the infected participants (54.3 binding antibody unit (BAU)/mL vs 26.5 BAU/mL, p=0.030). The difference in reactivity between spike-specific CD4+ and CD8+ T lymphocytes in the two groups was not significant. CONCLUSION AND RELEVANCE: The study results demonstrate rates of 59% in breakthrough infections after the third SARS-CoV-2 mRNA vaccination in ocrelizumab-treated patients with MS, without resulting in critical disease courses. These findings suggest the need for continuous development of prophylactic treatments when proved important in the protection of severe breakthrough infection.

Sentinel surveillance and epidemiology of Clostridioides difficile in Denmark, 2016 to 2019.

BackgroundSince 2008, Danish national surveillance of Clostridioides difficile has focused on binary toxin-positive strains in order to monitor epidemic types such as PCR ribotype (RT) 027 and 078. Additional surveillance is needed to provide a more unbiased representation of all strains from the clinical reservoir.AimSetting up a new sentinel surveillance scheme for an improved understanding of type distribution relative to time, geography and epidemiology, here presenting data from 2016 to 2019.MethodsFor 2─4 weeks in spring and autumn each year between 2016 and 2019, all 10 Danish Departments of Clinical Microbiology collected faecal samples containing toxigenic C. difficile. Isolates were typed at the national reference laboratory at Statens Serum Institut. The typing method in 2016-17 used tandem-repeat-sequence typing, while the typing method in 2018-19 was whole genome sequencing.ResultsDuring the study period, the sentinel surveillance scheme included ca 14-15% of all Danish cases of C. difficile infections. Binary toxin-negative strains accounted for 75% and 16 of the 20 most prevalent types. The most common sequence types (ST) were ST2/13 (RT014/020) (19.5%), ST1 (RT027) (10.8%), ST11 (RT078) (6.7%), ST8 (RT002) (6.6%) and ST6 (RT005/117) (5.1%). The data also highlighted geographical differences, mostly related to ST1 and temporal decline of ST1 (p = 0.0008) and the increase of ST103 (p = 0.002), ST17 (p = 0.004) and ST37 (p = 0.003), the latter three binary toxin-negative.ConclusionSentinel surveillance allowed nationwide monitoring of geographical differences and temporal changes in C. difficile infections in Denmark, including emerging types, regardless of binary toxin status.

Herpes Simplex Virus Type 1 Pneumonia-A Review.

BACKGROUND: Pneumonia due to herpes simplex virus (HSV) is uncommon but can be seen in immunocompromised patients and has been associated with poor prognosis in this population. AIM: The aim was to study the results, outcome and mortality of HSV pneumonia in immunocompromised patients and patients receiving mechanical ventilation. Furthermore, it has been unclear whether to initiate prophylactic treatment with acyclovir or not. METHODS: We have conducted a literature search using the keywords herpes simplex pneumonia, critically ill patients and intensive care unit for identification of relevant publications. FINDINGS: HSV pneumonia can cause severe infection or even death in immunocompromised patients and critically ill patients. A clear diagnosis of HSV pneumonia can be difficult to establish. Respiratory condition may improve after initiation of acyclovir but data is scarce. CONCLUSION: HSV pneumonia should be considered in the immunocompromised patient and/or the intensive care patient who continues to deteriorate despite appropriate treatment. The value of prophylactic treatment with acyclovir is unproven but should be considered.

Longitudinal trajectory patterns of plasma albumin and C-reactive protein levels around diagnosis, relapse, bacteraemia, and death of acute myeloid leukaemia patients.

BACKGROUND: No study has evaluated C-reactive protein (CRP) and plasma albumin (PA) levels longitudinally in patients with acute myeloid leukaemia (AML). METHODS: We studied defined events in 818 adult patients with AML in relation to 60,209 CRP and PA measures. We investigated correlations between CRP and PA levels and daily CRP and PA levels in relation to AML diagnosis, AML relapse, or bacteraemia (all ±30 days), and death (─30-0 days). RESULTS: On the AML diagnosis date (D0), CRP levels increased with higher WHO performance score (PS), e.g. patients with PS 3/4 had 68.1 mg/L higher CRP compared to patients with PS 0, adjusted for relevant covariates. On D0, the PA level declined with increasing PS, e.g. PS 3/4 had 7.54 g/L lower adjusted PA compared to PS 0. CRP and PA levels were inversely correlated for the PA interval 25-55 g/L (R = - 0.51, p < 10-5), but not for ≤24 g/L (R = 0.01, p = 0.57). CRP increases and PA decreases were seen prior to bacteraemia and death, whereas no changes occurred up to AML diagnosis or relapse. CRP increases and PA decreases were also found frequently in individuals, unrelated to a pre-specified event. CONCLUSIONS: PA decrease is an important biomarker for imminent bacteraemia in adult patients with AML.

The incidence of laboratory-confirmed cases of enteric pathogens in Denmark 2018: a national observational study.

BACKGROUND: Only a subset of enteric pathogens is under surveillance in Denmark, and knowledge on the remaining pathogens detected in acute gastroenteritis is limited. Here, we present the one-year incidence of all enteric pathogens diagnosed in Denmark, a high-income country, in 2018 and an overview of diagnostic methods used for detection. METHODS: All 10 departments of clinical microbiology completed a questionnaire on test methods and provided 2018-data of persons with positive stool samples with Salmonella species, Campylobacter jejuni/coli, Yersinia enterocolitica, Aeromonas species, diarrheagenic Escherichia coli (Enteroinvasive (EIEC), Shiga toxin-producing (STEC), Enterotoxigenic (ETEC), Enteropathogenic (EPEC), and intimin-producing/attaching and effacing (AEEC)), Shigella species., Vibrio cholerae, norovirus, rotavirus, sapovirus, adenovirus, Giardia intestinalis, Cryptosporidium species, and Entamoeba histolytica. RESULTS: Enteric bacterial infections were diagnosed with an incidence of 229.9 cases/100,000 inhabitants, virus had an incidence of 86/100,000 and enteropathogenic parasites of 12.5/100,000. Viruses constituted more than half of diagnosed enteropathogens for children below 2 years and elderly above 80 years. Diagnostic methods and algorithms differed across the country and in general PCR testing resulted in higher incidences compared to culture (bacteria), antigen-test (viruses), or microscopy (parasites) for most pathogens. CONCLUSIONS: In Denmark, the majority of detected infections are bacterial with viral agents primarily detected in the extremes of ages and with few intestinal protozoal infections. Incidence rates were affected by age, clinical setting and local test methods with PCR leading to increased detection rates. The latter needs to be taken into account when interpreting epidemiological data across the country.

Detection of infections by computerized capture of peaks in longitudinally measured C-reactive protein levels.

We developed four algorithms for the automatic capture of C-reactive protein (CRP) peaks in 296 adult patients with acute myeloid leukemia who had bloodstream infection (BSI) episodes, negative blood cultures (BCs) or possible infections where no BCs were performed. The algorithms detected CRP peaks for 418-446 of the 586 documented BSI episodes (71.3-76.1%) and 2714-3118 of the 4382 negative BCs (61.9-71.2%). The four algorithms captured 382-789 CRP peaks in which there were neither BSI episodes nor negative BCs. We conclude that automatic capture of CRP peaks is a tool for the monitoring of BSI episodes and possibly other infections in patients with acute myeloid leukemia.

One Day in Denmark: Comparison of Phenotypic and Genotypic Antimicrobial Susceptibility Testing in Bacterial Isolates From Clinical Settings.

Antimicrobial susceptibility testing (AST) should be fast and accurate, leading to proper interventions and therapeutic success. Clinical microbiology laboratories rely on phenotypic methods, but the continuous improvement and decrease in the cost of whole-genome sequencing (WGS) technologies make them an attractive alternative. Studies evaluating the performance of WGS-based prediction of antimicrobial resistance (AMR) for selected bacterial species have shown promising results. There are, however, significant gaps in the literature evaluating the applicability of WGS as a diagnostics method in real-life clinical settings against the range of bacterial pathogens experienced there. Thus, we compared standard phenotypic AST results with WGS-based predictions of AMR profiles in bacterial isolates without preselection of defined species, to evaluate the applicability of WGS as a diagnostics method in clinical settings. We collected all bacterial isolates processed by all Danish Clinical Microbiology Laboratories in 1 day. We randomly selected 500 isolates without any preselection of species. We performed AST through standard broth microdilution (BMD) for 488 isolates (n = 6,487 phenotypic AST results) and compared results with in silico antibiograms obtained through WGS (Illumina NextSeq) followed by bioinformatics analyses using ResFinder 4.0 (n = 5,229 comparisons). A higher proportion of AMR was observed for Gram-negative bacteria (10.9%) than for Gram-positive bacteria (6.1%). Comparison of BMD with WGS data yielded a concordance of 91.7%, with discordant results mainly due to phenotypically susceptible isolates harboring genetic AMR determinants. These cases correspond to 6.2% of all isolate-antimicrobial combinations analyzed and to 6.8% of all phenotypically susceptible combinations. We detected fewer cases of phenotypically resistant isolates without any known genetic resistance mechanism, particularly 2.1% of all combinations analyzed, which corresponded to 26.4% of all detected phenotypic resistances. Most discordances were observed for specific combinations of species-antimicrobial: macrolides and tetracycline in streptococci, ciprofloxacin and ß-lactams in combination with ß-lactamase inhibitors in Enterobacterales, and most antimicrobials in Pseudomonas aeruginosa. WGS has the potential to be used for surveillance and routine clinical microbiology. However, in clinical microbiology settings and especially for certain species and antimicrobial agent combinations, further developments in AMR gene databases are needed to ensure higher concordance between in silico predictions and expected phenotypic AMR profiles.

Impact of C-reactive protein and albumin levels on short, medium, and long term mortality in patients with diffuse large B-cell lymphoma.

Objectives and study design: In this population-based study of 602 patients, we amended C-reactive protein (CRP) and plasma albumin (PA) levels around the diagnosis of diffuse large B-cell lymphoma (DLBCL) to the International Prognostic Index (IPI) and assessed 0-90, 91-365, and +365-day survival.Results: The CRP did not contribute to the IPI's prognostic or discriminatory ability, regardless of time period, particularly not in models with PA. In contrast, the PA was an important contributor, especially in the 0-90 day period, but also up to one year after the diagnosis. For day 0-90, the model with the IPI only had an Area Under the Receiver Operating Characteristics (AUROC) of 0.742, whereas the IPI with PA as a continuous variable rendered an AUROC of 0.841. Especially the lower PA quartile (18-32 g/L) contributed to the worse prognosis.Conclusions: The amendment of PA to the IPI may significantly improve the short-term prognostic and discriminative ability.Key messagesThe amendment of the plasma albumin (PA) level to the International Prognostic Index significantly improved the prediction of mortality up to one year after the diagnosis of diffuse large B-cell lymphoma.It was especially the lower quartile of the PA level (18-32 g/L) that contributed to the worse prognosis.

One Day in Denmark: Nationwide point-prevalence survey of human bacterial isolates and comparison of classical and whole-genome sequence-based species identification methods.

OBJECTIVES: Implementing whole-genome sequencing (WGS) technologies in clinical microbiology laboratories can increase the amount and quality of information available for healthcare practitioners. In this study, we analysed the applicability of this method and determined the distribution of bacterial species processed in clinical settings in Denmark. METHODS: We performed a point-prevalence study of all bacterial isolates (n = 2,009) processed and reported in the Clinical Microbiology Laboratories in Denmark in one day in January 2018. We compared species identification as performed by classical methods (MALDI-TOF) and by bioinformatics analysis (KmerFinder and rMLST) of WGS (Illumina NextSeq) data. We compared the national point-prevalence of bacterial isolates observed in clinical settings with the research attention given to those same genera in scientific literature. RESULTS: The most prevalent bacterium was Escherichia coli isolated from urine (n = 646), followed by Staphylococcus spp. from skin or soft tissues (n = 197). The distribution of bacterial species throughout the country was not homogeneous. We observed concordance of species identification for all methods in 95.7% (n = 1,919) of isolates, furthermore obtaining concordance for 99.7% (n = 1,999) at genus level. The number of scientific publications in the country did not correlate with the number of bacterial isolates of each genera analysed in this study. CONCLUSIONS: WGS technologies have the potential to be applied in clinical settings for routine diagnostics purposes. This study also showed that bioinformatics databases should be continuously improved and results from local point-prevalence surveys should not be applied at national levels without previously determining possible regional variations.

Targeted AntiBiotics for Chronic pulmonary diseases (TARGET ABC): can targeted antibiotic therapy improve the prognosis of Pseudomonas aeruginosa-infected patients with chronic pulmonary obstructive disease, non-cystic fibrosis bronchiectasis, and asthma? A multicenter, randomized, controlled, open-label trial.

BACKGROUND: Pseudomonas aeruginosa infection is seen in chronic pulmonary disease and is associated with exacerbations and poor long-term prognosis. However, evidence-based guidelines for the management and treatment of P. aeruginosa infection in chronic, non-cystic fibrosis (CF) pulmonary disease are lacking. The aim of this study is to investigate whether targeted antibiotic treatment against P. aeruginosa can reduce exacerbations and mortality in patients with chronic obstructive pulmonary disease (COPD), non-CF bronchiectasis, and asthma. METHODS: This study is an ongoing multicenter, randomized, controlled, open-label trial. A total of 150 patients with COPD, non-CF bronchiectasis or asthma, and P. aeruginosa-positive lower respiratory tract samples will be randomly assigned with a 1:1 ratio to either no antibiotic treatment or anti-pseudomonal antibiotic treatment with intravenous beta-lactam and oral ciprofloxacin for 14 days. The primary outcome, analyzed with two co-primary endpoints, is (i) time to prednisolone and/or antibiotic requiring exacerbation or death, in the primary or secondary health sector, within days 20-365 from study allocation and (ii) days alive and without exacerbation within days 20-365 from the study allocation. DISCUSSION: This trial will determine whether targeted antibiotics can benefit future patients with chronic, non-CF pulmonary disease and P. aeruginosa infection in terms of reduced morbidity and mortality, thus optimizing therapeutic approaches in this large group of chronic patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT03262142 . Registered on August 25, 2017.

SARS-CoV-2 seroprevalence among 7950 healthcare workers in the Region of Southern Denmark.

OBJECTIVE: Healthcare workers (HCWs) carry a pronounced risk of acquiring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The aim of this study was to determine the seroprevalence and potential risk factors of SARS-CoV-2 infection among HCWs in the Region of Southern Denmark after the first pandemic wave in the spring of 2020. METHODS: This was an observational study conducted between May and June 2020. SARS-CoV-2 IgG and IgM antibodies were measured in plasma. Participants were asked to complete a questionnaire consisting of demographic information, risk factors, and COVID-19-related symptoms. RESULTS: A total of 7950 HCWs participated. The seroprevalence of SARS-CoV-2 antibodies was 2.1% (95% confidence interval (CI) 1.8-2.4%). Seropositive participants were significantly older (mean age 48.9 years vs 46.7 years in seronegative participants, P = 0.022) and a higher percentage had experienced at least one symptom of COVID-19 (P < 0.001). The seroprevalence was significantly higher among HCWs working on dedicated COVID-19 wards (3.5%; OR 2.02, 95% CI 1.44-2.84). Seroprevalence was significantly related to 11-50 close physical contacts per day outside work (OR 1.54, 95% CI 1.07-2.22). CONCLUSIONS: The prevalence of SARS-CoV-2 antibodies was low in HCWs. However, the occupational risk of contracting the infection was found to be higher for those working on dedicated COVID-19 wards. Further, the results imply that attention should be paid to occupational risk factors in planning pandemic preparedness.

Danish Whole-Genome-Sequenced Candida albicans and Candida glabrata Samples Fit into Globally Prevalent Clades.

Candida albicans and Candida glabrata are opportunistic fungal pathogens with increasing incidence worldwide and higher-than-expected prevalence in Denmark. We whole-genome sequenced yeast isolates collected from Danish Clinical Microbiology Laboratories to obtain an overview of the Candida population in the country. The majority of the 30 C. albicans isolates were found to belong to three globally prevalent clades, and, with one exception, the remaining isolates were also predicted to cluster with samples from other geographical locations. Similarly, most of the eight C. glabrata isolates were predicted to be prevalent subtypes. Antifungal susceptibility testing proved all C. albicans isolates to be susceptible to both azoles and echinocandins. Two C. glabrata isolates presented azole-resistant phenotypes, yet all were susceptible to echinocandins. There is no indication of causality between population structure and resistance phenotypes for either species.