Chronic kidney disease and risk of bloodstream infections and sepsis: a 17-year follow-up of the population-based Trøndelag Health Study in Norway.

PURPOSE: Bloodstream infections (BSI) and sepsis are important causes of hospitalization, loss of health, and death globally. Targetable risk factors need to be identified to improve prevention and treatment. In this study, we aimed to evaluate the association of chronic kidney disease (CKD) and risk of and mortality from BSI and sepsis in the general population during a 22-year period. METHODS: We conducted a prospective cohort study among participants in the population-based Norwegian HUNT Study, where 68,438 participated. The median follow-up time was 17.4 years. The exposures were estimated glomerular filtration rate (eGFR) and albumin-creatinine ratio (ACR) in urine. The outcomes were hazard ratios (HR) of hospital admission or death due to BSI or sepsis. The associations were adjusted for age, sex, diabetes, obesity, systolic blood pressure, smoking status, and cardiovascular disease. RESULTS: Participants with eGFR < 30 ml/min/1.732 had HR 3.35 for BSI (95% confidence intervals (CI) 2.12-5.3) and HR 2.94 for sepsis (95% CI 1.82-4.8) compared to normal eGFR (≥ 90 ml/min/1.732). HRs of death from BSI and sepsis were 4.2 (95% CI 1.71-10.4) and 4.1 (95% CI 1.88-8.9), respectively. Participants with severely increased albuminuria (ACR > 30 mg/mmol) had HR 3.60 for BSI (95% CI 2.30-5.6) and 3.14 for sepsis (95% CI 1.94-5.1) compared to normal albumin excretion (ACR < 3 mg/mmol). HRs of death were 2.67 (95% CI 0.82-8.7) and 2.16 (95% CI 0.78-6.0), respectively. CONCLUSION: In this large population-based cohort study, CKD was clearly associated with an increased risk of BSI and sepsis and related death.

Incidence of invasive infections with Group B streptococcus in adults in Norway 1996-2019: a nationwide registry-based case-control study.

PURPOSE: Group B streptococcus (GBS) colonizes the gastrointestinal and vaginal mucosa in healthy adults, but has also become an increasing cause of invasive infection. The aims of this study were to describe the incidence and factors associated with the occurrence of invasive GBS disease in adults in Norway. METHODS: We performed a nationwide retrospective case-control study of invasive GBS infections during 1996-2019, with two control groups; invasive Group A streptococcal disease (GAS) to control for changes in surveillance and diagnostics, and a second representing the general population. RESULTS: A total of 3710 GBS episodes were identified. The age-standardized incidence rate increased steadily from 1.10 (95% CI 0.80-1.50) in 1996 to 6.70 (95% CI 5.90-7.50) per 100,000 person-years in 2019. The incidence rate had an average annual increase of 6.44% (95% CI 5.12-7.78). Incidence rates of GAS varied considerably, and there was no evidence of a consistent change over the study period. GBS incidence was highest among adults > 60 years of age. Cardiovascular disease, cancer, and diabetes were the most common comorbid conditions. There was a shift in the distribution of capsular serotypes from three dominant types to more equal distribution among the six most common serotypes. CONCLUSIONS: The incidence of invasive GBS disease in adults increased significantly from 1996 to 2019. The increasing age of the population with accompanying underlying comorbid conditions might contribute to the increasing burden of invasive GBS disease. Interestingly, type 1 diabetes was also associated with the occurrence of invasive GBS disease.

Chronic HIV Infection Increases Monocyte NLRP3 Inflammasome-Dependent IL-1α and IL-1ß Release.

Antiretroviral treatment (ART) has converted HIV from a lethal disease to a chronic condition, yet co-morbidities persist. Incomplete immune recovery and chronic immune activation, especially in the gut mucosa, contribute to these complications. Inflammasomes, multi-protein complexes activated by innate immune receptors, appear to play a role in these inflammatory responses. In particular, preliminary data indicate the involvement of IFI16 and NLRP3 inflammasomes in chronic HIV infection. This study explores inflammasome function in monocytes from people with HIV (PWH); 22 ART-treated with suppressed viremia and 17 untreated PWH were compared to 33 HIV-negative donors. Monocytes were primed with LPS and inflammasomes activated with ATP in vitro. IFI16 and NLRP3 mRNA expression were examined in a subset of donors. IFI16 and NLRP3 expression in unstimulated monocytes correlated negatively with CD4 T cell counts in untreated PWH. For IFI16, there was also a positive correlation with viral load. Monocytes from untreated PWH exhibit increased release of IL-1α, IL-1ß, and TNF compared to treated PWH and HIV-negative donors. However, circulating monocytes in PWH are not pre-primed for inflammasome activation in vivo. The findings suggest a link between IFI16, NLRP3, and HIV progression, emphasizing their potential role in comorbidities such as cardiovascular disease. The study provides insights into inflammasome regulation in HIV pathogenesis and its implications for therapeutic interventions.

Coding practice for sepsis 2008-21. / Kodepraksis ved sepsis 2008­21.

Background: Sepsis has a high incidence and mortality rate. Accurate data are needed for health service planning and for research, and there is a need to identify coding practices in Norway. Material and method: All patients over 17 years of age who had been admitted to Norwegian hospitals with sepsis in the period 2008-21 were identified using diagnostic codes for infection plus organ failure, and specific codes for sepsis, from the Norwegian Patient Registry. Results: There were 317 705 admissions with diagnostic codes for sepsis, of which 210 391 (66.2 %) were sepsis with a known focus, 77 627 (24.4 %) were of unknown focus and 29 687 (9.3 %) were codes for both a known and unknown focus. The percentage of sepsis episodes coded with a known focus varied between the health regions. The highest percentage was in the Western Norway Regional Health Authority (72.1 %, 95 % confidence interval (CI): 71.8 to 72.5), and the lowest was in the Central Norway Regional Health Authority (59.2 %, 95 %, CI 58.7 to 59.7). The use of codes with a known focus increased each year on average by 3.2 % (95 % CI 2.7 to 3.6, from 47.5 % in 2008 to 82.3 % in 2021), while the use of codes with an unknown focus decreased by 2.3 % (95 % CI -2.7 to -1.9) from 37.8 % in 2008 to 13.0 % in 2021. Known and unknown focus combined also decreased by 0.9 % per year on average (95 % CI -1.0 to -0.8) from 14.3 % in 2008 to 4.1 % in 2021. Interpretation: The coding of sepsis in Norwegian hospitals has become more uniform.

The causal role of C-reactive protein and interleukin-6 on anxiety and depression symptoms and life satisfaction: Mendelian randomisation analyses in the HUNT study.

BACKGROUND: Serum levels of C-reactive protein (CRP) and interleukin-6 (IL-6) have been associated with anxiety and depression in cross-sectional and Mendelian randomisation studies, but results regarding the effect size and direction have been mixed. A recent Mendelian Randomisation (MR) study suggested that CRP may decrease and IL-6 may increase anxiety and depression symptoms. METHODS: Among 68 769 participants of the population-based Trøndelag Health Study (HUNT), we performed cross-sectional observational and one-sample MR analyses of serum CRP and two-sample MR analysis of serum IL-6. The main outcomes were symptoms of anxiety and depression assessed using the Hospital Anxiety and Depression Scale (HADS) and life satisfaction assessed using a seven-level ordinal questionnaire where higher scores indicate lower life satisfaction. RESULTS: In cross-sectional observational analyses, a doubling in serum CRP level was associated with 0.27% (95% CI -0.20 to 0.75) difference in HADS depression score (HADS-D), -0.77% (95% CI -1.24 to -0.29) difference in HADS anxiety score (HADS-A) and -0.10% (95% CI -0.41 to 0.21) difference in life satisfaction score. In one-sample MR analyses, a doubling in serum CRP was associated with 2.43% (95% CI -0.11 to 5.03) higher HADS-D, 1.94% (95% CI -0.58 to 4.52) higher HADS-A, and 2.00% (95% CI 0.45 to 3.59) higher life satisfaction score. For IL-6, causal point estimates were in the opposite direction, but imprecise and far from conventional criteria for statistical significance. CONCLUSIONS: Our results do not support a major causal role of serum CRP on anxiety and depression symptoms and life satisfaction, but provides weak evidence that serum CRP may modestly increase anxiety and depression symptoms and reduce life satisfaction. Our findings do not support the recent suggestion that serum CRP may lower anxiety and depression symptoms.

Trends in mortality after a sepsis hospitalization: a nationwide prospective registry study from 2008 to 2021.

BACKGROUND: Few studies have reported on mortality beyond one year after sepsis. We aim to describe trends in short- and long-term mortality among patients admitted with sepsis, and to describe the association between clinical characteristics and mortality for improved monitoring, treatment and prognosis. METHODS: Patients ≥ 18 years admitted to all Norwegian hospitals (2008-2021) with a first sepsis episode were identified using Norwegian Patient Registry and International Classification of Diseases 10th Revision codes. Sepsis was classified as implicit (known infection site plus organ dysfunction), explicit (unknown infection site), or COVID-19-related sepsis. The outcome was all-cause mortality. We describe age-standardized 30-day, 90-day, 1-, 5- and 10-year mortality for each admission year and estimated the annual percentage change with 95% confidence interval (CI). The association between clinical characteristics and all-cause mortality is reported as hazard ratios (HRs) adjusted for age, sex and calendar year in Cox regression. RESULTS: The study included 222,832 patients, of whom 127,059 (57.1%) had implicit, 92,928 (41.7%) had explicit, and 2,845 (1.3%) had COVID-19-related sepsis (data from 2020 and 2021). Trends in overall age-standardized 30-day, 90-day, 1- and 5-year mortality decreased by 0.29 (95% CI - 0.39 to - 0.19), 0.43 (95% CI - 0.56 to - 0.29), 0.61 (95% CI - 0.73 to - 0.49) and 0.66 (95% CI - 0.84 to - 0.48) percent per year, respectively. The decrease was observed for all infections sites but was largest among patients with respiratory tract infections. Implicit, explicit and COVID-19-related sepsis had largely similar overall mortality, with explicit sepsis having an adjusted HR of 0.980 (95% CI 0.969 to 0.991) and COVID-19-related sepsis an adjusted HR of 0.916 (95% CI 0.836 to 1.003) compared to implicit sepsis. Patients with respiratory tract infections have somewhat higher mortality than those with other infection sites. Number of comorbidities was positively associated with mortality, but mortality varied considerably between different comorbidities. Similarly, number of acute organ dysfunctions was strongly associated with mortality, whereas the risk varied for each type of organ dysfunction. CONCLUSION: Overall mortality has declined over the past 14 years among patients with a first sepsis admission. Comorbidity, site of infection, and acute organ dysfunction are patient characteristics that are associated with mortality. This could inform health care workers and raise the awareness toward subgroups of patients that needs particular attention to improve long-term mortality.

Return to work after hospitalization for sepsis: a nationwide, registry-based cohort study.

BACKGROUND: Sepsis survivors commonly experience functional impairment, which may limit return to work. We investigated return to work (RTW) of patients hospitalized with sepsis and the associations with patient and clinical characteristics. METHODS: Working-age patients (18-60 years) admitted to a Norwegian hospital with sepsis between 2010 and 2021 were identified using the Norwegian Patient Registry and linked to sick-leave data from the Norwegian National Social Security System Registry. The main outcome was proportion of RTW in patients hospitalized with sepsis at 6 months, 1 year, and 2 years after discharge. Secondary outcomes were time trends in age-standardized proportions of RTW and probability of sustainable RTW (31 days of consecutive work). The time trends were calculated for each admission year, reported as percentage change with 95% confidence interval (CI). Time-to-event analysis, including crude and adjusted hazard risk (HRs), was used to explore the association between sustainable RTW, characteristics and subgroups of sepsis patients (intensive care unit (ICU) vs. non-ICU and COVID-19 vs. non-COVID-19). RESULTS: Among 35.839 hospitalizations for sepsis among patients aged 18-60 years, 12.260 (34.2%) were working prior to hospitalization and included in this study. The mean age was 43.7 years. At 6 months, 1 year, and 2 years post-discharge, overall estimates showed that 58.6%, 67.5%, and 63.4%, respectively, were working. The time trends in age-standardized RTW for ICU and non-ICU sepsis patients remained stable over the study period, except the 2-year age-standardized RTW for non-ICU patients that declined by 1.51% (95% CI - 2.22 to - 0.79) per year, from 70.01% (95% CI 67.21 to 74.80) in 2010 to 57.04% (95% CI 53.81-60.28) in 2019. Characteristics associated with sustainable RTW were younger age, fewer comorbidities, and fewer acute organ dysfunctions. The probability of sustainable RTW was lower in ICU patients compared to non-ICU patients (HR 0.56; 95% CI 0.52-0.61) and higher in patients with COVID-19-related sepsis than in sepsis patients (HR 1.31; 95% CI 1.15-1.49). CONCLUSION: Absence of improvement in RTW proportions over time and the low probability of sustainable RTW in sepsis patients need attention, and further research to enhance outcomes for sepsis patients is required.

Diagnostic stewardship aiming at expectorated or induced sputum promotes microbial diagnosis in community-acquired pneumonia.

PURPOSE: Studies on aetiology of community-acquired pneumonia (CAP) vary in terms of microbial sampling methods, anatomical locations, and laboratory analyses, since no gold standard exists. In this large, multicentre, retrospective, regional study from Norway, our primary objective was to report the results of a strategic diagnostic stewardship intervention, targeting diagnostic yield from lower respiratory tract sampling. The secondary objective was to report hospitalized CAP aetiology and the diagnostic yield of various anatomical sampling locations. METHODS: Medical records from cases diagnosed with hospitalized CAP were collected retrospectively from March throughout May for three consecutive years at six hospitals. Between year one and two, we launched a diagnostic stewardship intervention at the emergency room level for the university teaching hospital only. The intervention was multifaceted aiming at upscaling specimen collection and enhancing collection techniques. Year one at the interventional hospital and every year at the five other emergency hospitals were used for comparison. RESULTS: Of the 1280 included cases of hospitalized CAP, a microbiological diagnosis was established for 29.1% among 1128 blood cultures and 1444 respiratory tract specimens. Blood cultures were positive for a pathogenic respiratory tract microbe in 4.9% of samples, whereas upper and lower respiratory tract samples overall provided a probable microbiological diagnosis in 21.3% and 47.5%, respectively. Expectorated or induced sputum overall provided aetiology in 51.7% of the samples. At the interventional hospital, the number of expectorated or induced sputum samples were significantly increased, and diagnostic yield from expectorated or induced sputum was significantly enhanced from 41.2 to 62.0% after the intervention (p = 0.049). There was an over-representation of samples from the interventional hospital during the study period. Non-typeable Haemophilus influenza and Streptococcus pneumoniae accounted for 25.3% and 24.7% of microbiologically confirmed cases, respectively. CONCLUSION: Expectorated or induced sputum outperformed other sampling methods in providing a reliable microbiological diagnosis for hospitalized CAP. A diagnostic stewardship intervention significantly improved diagnostic yield of lower respiratory tract sampling.

Antimicrobial therapy of community-acquired pneumonia during stewardship efforts and a coronavirus pandemic: an observational study.

BACKGROUND: Community-acquired pneumonia (CAP) is the most frequent infection diagnosis in hospitals. Antimicrobial therapy for CAP is depicted in clinical practice guidelines, but adherence data and effect of antibiotic stewardship measures are lacking. METHODS: A dedicated antibiotic team pointed out CAP as a potential target for antimicrobial stewardship (AMS) measures at a 1.000-bed, tertiary care, teaching university hospital in Norway from March until May for the years 2016 throughout 2021. The aim of the AMS program was to increase diagnostic and antimicrobial therapy adherence to national clinical practice guideline recommendations through multiple and continuous AMS efforts. Descriptive statistics were retrospectively used to delineate antimicrobial therapy for CAP. The primary outcomes were proportions that received narrow-spectrum beta-lactams, and broad-spectrum antimicrobial therapy. RESULTS: 1.112 CAP episodes were identified. The annual proportion that received narrow-spectrum beta-lactams increased from 56.1 to 74.4% (p = 0.045). Correspondingly, the annual proportion that received broad-spectrum antimicrobial therapy decreased from 34.1 to 17.1% (p = 0.002). Trends were affected by the coronavirus pandemic. Mortality and 30-day readmission rates remained unchanged. De-escalation strategies were frequently unutilized, and overall therapy duration exceeded clinical practice guideline recommendations substantially. Microbiologically confirmed CAP episodes increased from 33.7 to 56.2% during the study period. CONCLUSION: CAP is a suitable model condition that is sensitive to AMS measures. A continuous focus on improved microbiological diagnostics and antimicrobial therapy initiation is efficient in increasing adherence to guideline recommendations. There is an unmet need for better antimicrobial de-escalation strategies.

The Role of FER rs4957796 in the Risk of Developing and Dying from a Bloodstream Infection: A 23-Year Follow-up of the Population-based Nord-Trøndelag Health Study.

BACKGROUND: Bloodstream infection and sepsis are major causes of health loss worldwide, and it is important to identify patients at risk of developing and dying from these conditions. The single-nucleotide polymorphism most strongly associated with sepsis mortality is FER rs4957796. However, it is not known how this variant is associated with bloodstream infection incidence and mortality. METHODS: We used prospective data from 1995-2017 from the population-based HUNT Study. Genotypes were ascertained from blood samples, and additional genotypes were imputed. Information on bloodstream infection and diagnosis codes at hospitalization were collected through record linkage with all hospitals in the area. RESULTS: A total of 69 294 patients were included. Patients with the rs4957796 CC genotype had an increased risk of developing a bloodstream infection compared with the TT genotype (hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.00-1.43). However, there was a protective additive effect of the C allele in terms of mortality in the total study population (HR, 0.77; 95% CI, .64-.92 per copy of the C allele) and among bloodstream infection patients (odds ratio, 0.70; 95% CI, .58-.85 per copy of the C allele). The results did not appear to be affected by selection bias. CONCLUSIONS: The rs4957796 CC genotype was associated with an increased risk of contracting a bloodstream infection but with a reduced risk of dying from one. The latter finding is in line with studies of sepsis case fatality, while the former expands our understanding of the immunoregulatory role of this polymorphism.

Epidemiological and clinical characteristics of immunocompromised patients infected with Pneumocystis jirovecii in a twelve-year retrospective study from Norway.

BACKGROUND: Pneumocystis pneumonia (PCP) severely menaces modern chemotherapy and immunosuppression. Detailed description of the epidemiology of Pneumocystis jirovecii today is needed to identify candidates for PCP-prophylaxis. METHODS: We performed a 12-year retrospective study of patients with P. jirovecii detected by polymerase chain reaction in Central Norway. In total, 297 patients were included. Comprehensive biological, clinical and epidemiological data were abstracted from patients' medical records. Regional incidence rates and testing trends were also assessed. RESULTS: From 2007 to 2017 we found a 3.3-fold increase in testing for P. jirovecii accompanied by a 1.8-fold increase in positive results. Simultaneously, regional incidence rates doubled from 5.0 cases per 100,000 person years to 10.8. A majority of the study population had predisposing conditions other than human immunodeficiency virus (HIV). Hematological (36.0%) and solid cancers (25.3%) dominated. Preceding corticosteroids were a common denominator for 72.1%. Most patients (74.4%) presented with at least two cardinal symptoms; cough, dyspnea or fever. Main clinical findings were hypoxia, cytopenias and radiological features consistent with PCP. A total of 88 (29.6%) patients required intensive care and 121 (40.7%) suffered at least one complication. In-hospital mortality was 21.5%. Three patients (1.0%) had received prophylaxis. CONCLUSIONS: P. jirovecii is re-emerging; likely due to increasing immunosuppressants use. This opportunistic pathogen threatens the life of heterogenous non-HIV immunosuppressed populations currently at growth. Corticosteroids seem to be a major risk factor. A strategy to increase prophylaxis is called for.

Genome-Wide Linkage Analysis of the Risk of Contracting a Bloodstream Infection in 47 Pedigrees Followed for 23 Years Assembled From a Population-Based Cohort (the HUNT Study).

OBJECTIVES: Bloodstream infection is an important cause of death worldwide. The main objective of this study was to identify genetic loci linked to risk of contracting a bloodstream infection. DESIGN: Genome-wide linkage analysis. SETTING: Population-based, Norwegian cohort, followed between 1995 and 2017. SUBJECTS: Among 69,423 genotyped subjects, there were 47 families with two or more second-degree relatives with bloodstream infection in the follow-up period. There were 365 subjects in these families, of which 110 were affected. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The cohort was genotyped using Illumina HumanCoreExome (Illumina, San Diego, CA) arrays. Before linkage analysis, single-nucleotide polymorphisms were pruned and clumped. In nonparametric linkage analysis using an exponential model, we found three loci with a suggestive linkage to bloodstream infection, all on chromosome 4, at 46.6 centimorgan (logarithm of odds, 2.3), 57.7 centimorgan (logarithm of odds, 3.2), and 70.0 centimorgan (logarithm of odds, 2.1). At the peak of the lead region are three genes: TLR10, TLR1, and TLR6. CONCLUSIONS: Variations in the TLR10/1/6 locus appear to be linked with the risk of contracting a bloodstream infection.

Correction to: Monitoring quality of care for peripheral intravenous catheters; feasibility and reliability of the peripheral intravenous catheters mini questionnaire (PIVC-miniQ).

An amendment to this paper has been published and can be accessed via the original article.

Use of peripheral venous catheters in two Norwegian hospitals. / Bruk av perifere venekatetre ved to norske sykehus.

BACKGROUND: Most patients in Norwegian hospitals are routinely given one or more peripheral venous catheters. A peripheral venous catheter is considered to be a benign device but may entail a risk of local infection with resulting bloodstream infection and sepsis. Good practice in the insertion and care of these catheters is essential to prevent infection. MATERIAL AND METHOD: This study presents Norwegian data from the 'One Million Global Catheters Study', which evaluated practice in relation to peripheral venous catheters in 419 hospitals in 51 countries. Two Norwegian hospitals collected data from medical and surgical wards on a single day in November 2014 (Levanger Hospital) and a single day in February 2015 (St Olavs Hospital). Professional development nursing specialists recorded observations of peripheral venous catheters such as insertion site, dressing, documentation and indication. RESULTS: We evaluated 136 peripheral venous catheters in a total of 121 patients. We found 44 (32.4 %) catheters associated with various clinical problems such as pain, redness or swelling around the insertion site, catheter dislocation, or blood in the infusion set. Altogether 50 peripheral venous catheters (36.8 %) were not in use for either medications or fluid on the day in question. In 93 of 131 cases (71.0 %), there was no documentation of venous catheter assessment in the previous 24 hours. INTERPRETATION: Care and monitoring of venous catheters could be significantly improved. There was considerable incidence of unused peripheral venous catheters, and lack of documentation was widespread.

Monitoring quality of care for peripheral intravenous catheters; feasibility and reliability of the peripheral intravenous catheters mini questionnaire (PIVC-miniQ).

BACKGROUND: Peripheral intravenous catheters (PIVCs) account for a mean of 38% of catheter associated bloodstream infections (CABSI) with Staphylococcus aureus, which are preventable if deficiencies in best practice are addressed. There exists no feasible and reliable quality surveillance tool assessing all important areas related to PIVC quality. Thus, we aimed to develop and test feasibility and reliability for an efficient quality assessment tool of overall PIVC quality. METHODS: The Peripheral Intravenous Catheter- mini Questionnaire, PIVC-miniQ, consists of 16 items calculated as a sum score of problems regarding the insertion site, condition of dressing and equipment, documentation, and indication for use. In addition, it contains background variables like PIVC site, size and insertion environment. Two hospitals tested the PIVC-miniQ for feasibility and inter-rater agreement. Each PIVC was assessed twice, 2-5 min apart by two independent raters. We calculated the intraclass correlation coefficient (ICC) for each hospital and overall. For each of the 16 items, we calculated negative agreement, positive agreement, absolute agreement, and Scott's pi. RESULTS: Sixty-three raters evaluated 205 PIVCs in 177 patients, each PIVC was assessed twice by independent raters, in total 410 PIVC observations. ICC between raters was 0.678 for hospital A, 0.577 for hospital B, and 0.604 for the pooled data. Mean time for the bedside assessment of each PIVC was 1.40 (SD 0.0007) minutes. The most frequent insertion site symptom was "pain and tenderness" (14.4%), whereas the most prevalent overall problem was lack of documentation of the PIVC (26.8%). Up to 50% of PIVCs were placed near joints (wrist or antecubital fossae) or were inserted under suboptimal conditions, i.e. emergency department or ambulance. CONCLUSIONS: Our study highlights the need for PIVC quality surveillance on ward and hospital level and reports the PIVC-miniQ to be a reliable and time efficient tool suitable for frequent point-prevalence audits.

Expression of neutrophil gelatinase-associated lipocalin (NGAL) in the gut in Crohn's disease.

The antimicrobial glycoprotein neutrophil gelatinase-associated lipocalin (NGAL) is strongly expressed in several infectious, inflammatory and malignant disorders, among these inflammatory bowel disease (IBD). Fecal and serum NGAL is elevated during active IBD and we have recently shown that fecal NGAL is a novel biomarker for IBD with a test performance comparable to the established fecal biomarker calprotectin. This study examines expression of NGAL in the healthy gut and in Crohn's disease (CD), with emphasis on the previously unexplored small intestine. Pinch biopsies were taken from active and inactive CD in jejunum, ileum and colon and from the same sites in healthy controls. Microarray gene expression showed that the NGAL gene, LCN2, was the second most upregulated among 1820 differentially expressed genes in terminal ileum comparing active CD and controls (FC 5.86, p = 0.027). Based on immunohistochemistry and in situ hybridization findings, this upregulation most likely represented increased expression in epithelial cells. Double immunofluorescence showed NGAL expression in 49% (range 19-70) of Paneth cells (PCs) in control ileum with no change during inflammation. In healthy jejunum, the NGAL expression in PCs was weak to none but markedly increased during active CD. We further found NGAL also in metaplastic PCs in colon. Finally, we show for the first time that NGAL is expressed in enteroendocrine cells in small intestine as well as in colon.

Anxiety and Depression Symptoms in a General Population and Future Risk of Bloodstream Infection: The HUNT Study.

OBJECTIVE: We examined whether anxiety and depression symptoms constitute increased risk of bloodstream infection (BSI), as a proxy for sepsis. METHODS: A general population with self-reported anxiety and depression symptoms was followed prospectively for hospital-verified BSI. Using multivariable Cox regression analysis, we estimated hazard ratios (HR) with 95% confidence intervals (CI) of BSI and BSI mortality, with and without statistical adjustment for comorbidities, BMI, and life-style factors that may confound or mediate the associations. RESULTS: During 14.8 years median follow-up of 59,301 individuals, 1578 (2.7%) experienced BSI and 328 (0.55%) participants died within 30 days after a BSI. Severe depression symptoms were associated with a 38% increased risk of BSI, adjusted for age, sex, and education (HR = 1.38, 95% CI = 1.10-1.73). The HR was attenuated to 1.23 (0.96-1.59) after adjustment for comorbidities and to 1.15 (0.86-1.53) after additional adjustment for BMI and life-style factors. For severe anxiety symptoms, the corresponding HRs were 1.48 (1.20-1.83), 1.35 (1.07-1.70), and 1.28 (0.99-1.64). Moderate symptoms of depression and anxiety were not associated with increased BSI risk. The analysis of BSI mortality yielded imprecise results but suggested an increased risk of BSI mortality in participants with moderate depression symptoms. CONCLUSIONS: Severe depression and anxiety symptoms were associated with a moderately increased risk of BSI. The association may, at least in part, be confounded or mediated by comorbidities, BMI, and life-style. Future research should investigate whether interventions targeting improved BMI and life-style may reduce the risk of BSI and sepsis in people with depression and anxiety symptoms.

Transcapillary fluid flux and inflammatory response during neonatal therapeutic hypothermia: an open, longitudinal, observational study.

BACKGROUND: Therapeutic hypothermia is neuroprotective in asphyxiated neonates by counteracting mechanisms contributing to brain injury. Although an initial increased permeability is part of an inflammatory reaction and thereby a natural healing process, an excessive endothelial permeability with edema formation may result in impaired hemodynamics. Reduced permeability may, however, benefit healing. Although plasma and interstitial colloid osmotic pressure are accessible and essential parameters for understanding fluid imbalance, the mechanisms of fluid exchange remain poorly understood. The potential influence of therapeutic hypothermia on plasma and interstitial colloid osmotic pressure, and the relationship between inflammatory markers and colloid osmotic pressure in asphyxiated neonates, was investigated. METHODS: Seventeen neonates with moderate to severe hypoxic ischemic encephalopathy, born after 35 weeks gestation, received servo-controlled whole body cooling before 6 h of age, followed by gradual rewarming after 72 h. All infants were treated according to a national hypothermia protocol. Interstitial fluid in the skin was collected at 7, 13, 25, 49, and 73 h after birth by subcutaneous implantation of multifilamentous nylon wicks with 60 min of implantation time. Biomarkers of inflammation and colloid osmotic pressure were measured in serum and interstitial fluid. RESULTS: A modest decrease in serum and interstitial colloid osmotic pressure was measured, leaving an unaltered difference in colloid osmotic pressure gradient. A decline in mean arterial pressure was observed between 7 and 13 h of life, with a concomitant decrease in positive fluid balance within the same time frame. White blood cell count and leukocyte subclasses dropped significantly throughout treatment, with elevated interstitial interleukin (IL)-1α and decreased serum IL-1RA, IL-6, and IL-10 during treatment time points. CONCLUSIONS: Colloid osmotic pressures measured in serum and interstitial fluid during asphyxia is lower than previously reported, with small alteration of pressure differences across capillaries, reducing vascular filtration. An inherent local and systemic regulation of inflammation together with changes in colloid osmotic pressure may indicate a possible preventive mechanism of edema generation during neonatal asphyxia and therapeutic hypothermia. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01044940 . Date of registration: January 8, 2010.

Keap1 regulates inflammatory signaling in Mycobacterium avium-infected human macrophages.

Several mechanisms are involved in controlling intracellular survival of pathogenic mycobacteria in host macrophages, but how these mechanisms are regulated remains poorly understood. We report a role for Kelch-like ECH-associated protein 1 (Keap1), an oxidative stress sensor, in regulating inflammation induced by infection with Mycobacterium avium in human primary macrophages. By using confocal microscopy, we found that Keap1 associated with mycobacterial phagosomes in a time-dependent manner, whereas siRNA-mediated knockdown of Keap1 increased M. avium-induced expression of inflammatory cytokines and type I interferons (IFNs). We show evidence of a mechanism whereby Keap1, as part of an E3 ubiquitin ligase complex with Cul3 and Rbx1, facilitates ubiquitination and degradation of IκB kinase (IKK)-ß thus terminating IKK activity. Keap1 knockdown led to increased nuclear translocation of transcription factors NF-κB, IFN regulatory factor (IRF) 1, and IRF5 driving the expression of inflammatory cytokines and IFN-ß. Furthermore, knockdown of other members of the Cul3 ubiquitin ligase complex also led to increased cytokine expression, further implicating this ligase complex in the regulation of the IKK family. Finally, increased inflammatory responses in Keap1-silenced cells contributed to decreased intracellular growth of M. avium in primary human macrophages that was reconstituted with inhibitors of IKKß or TANK-binding kinase 1 (TBK1). Taken together, we propose that Keap1 acts as a negative regulator for the control of inflammatory signaling in M. avium-infected human primary macrophages. Although this might be important to avoid sustained or overwhelming inflammation, our data suggest that a negative consequence could be facilitated growth of pathogens like M. avium inside macrophages.