Pre-analytical diagnostic differences despite high adherence to guidelines for gestational diabetes mellitus.

Regional variations in the prevalence of gestational diabetes mellitus (GDM) have been found across Denmark. The objectives of this exploratory survey were to evaluate adherence to the national guideline for screening and diagnosing GDM and to identify variations in pre-analytical or analytical factors, which could potentially contribute to variations in GDM prevalence across regions. In a national interview-based survey, obstetric departments and laboratories throughout Denmark handling GDM screening or diagnostic testing were invited to participate. Survey questionnaires were completed through personal interviews. In total, 21 of 22 identified obstetric departments and 44 of 45 identified laboratories participated. Adherence to guideline among obstetric departments ranged 67-100% and uniformity in laboratory procedures was high. However, the gestational age at the time of late diagnostic testing with oral glucose tolerance test (OGTT) varied considerably, with 48% (10/21) of departments testing outside the recommended 24-28 weeks' gestation. Procedural heterogeneity was most pronounced for the parts not described in current guidelines, with choice of laboratory equipment being the most diverse factor ranging 3-39% nationally. In conclusion, the overall adherence to the national guidelines was high across regions, and obstetric departments and laboratories had high uniformity in the procedures for screening and diagnosing GDM. Uniformity was generally high for procedures included in the guideline and low if not included. However, a high proportion of GDM testing was performed outside the recommended gestational window in late pregnancy, which may be a pre-analytical contributor to regional differences in GDM prevalence.

Validation of suPAR turbidimetric assay on Cobas® (c502 and c702) and comparison to suPAR ELISA.

suPAR is a plasma marker of chronic inflammation, and an elevated suPAR is consistently associated with worse outcome in a variety of clinical conditions. Quantification of suPAR is useful for determining patient risk in triage, but there is no fast automatized method for quick determination of suPAR. We developed and validated a rapid latex particle-enhanced turbidimetric immunoassay for quantification of plasma suPAR on the c502 and the c702 Roche Cobas® 8000 measurment systems. The turbidimetric assay was validated against the suPARnostic® ELISA (ViroGates, Denmark). This validation demonstrates suPAR can be analysed by turbidimetry giving very similar results (<15% difference) compared to the ELISA method and the observed correlations (n = 103) were strong, r > 0.95. Roche Cobas® 8000 instruments demonstrated repeatability and repoducibility, CV % at 3.4-4.1 and 5.7-11.4, respectively. The estimated limit of detection was 1.30 µg/L and 1.31 µg/L for the Cobas® c502 and c702, respectively. Dilution tests showed linearity of suPAR from 1.8 to 26.5 µg/L. The acceptable concentrations of Bilirubin, Intralipid and Hemoglobin, were 350 µmol/L, 3.3 g/L and 1.4 g/L, respectively. suPAR can be quantified reproducibly within 10 min using a turbidimetry assay. This assay is faster than ELISA with similar results, making it suitable for clinical routine analysis.

Hygiene of venepuncture tourniquets in Denmark.

Tourniquets are widely used to make the vein more visible prior to blood collection. Venepuncture tourniquets are however a non-sterile and potentially reusable equipment. Several studies have shown that they are colonised by a variety of pathogenic bacteria and consecutively use of the same tourniquet on multiple patients will increase the risk of a nosocomial infection. This matter is however only scarcely studied. The objective of this study was to investigate the nationwide use of disposable and non-disposable venepuncture tourniquets and the standardised procedures for cleaning the tourniquets. A questionnaire concerning use and cleaning of tourniquets was therefore sent to all major Danish clinical biochemistry laboratories (n = 12). All but one laboratory had a local procedure for usage and handling of tourniquets, including structured procedures for cleaning. Despite this, only 75% of laboratories had a guideline for cleaning the tourniquets and only 50% had a specified cleaning program. At the hospitals using non-disposable tourniquets the handling differed considerably and at two hospitals the tourniquets were only cleaned once a week, while one laboratory did not clean the tourniquet before it was visibly stained. Of note, five of the eight hospitals using disposable tourniquets only disposed the tourniquets on a daily basis. In conclusion, there is a lack of guidelines for handling tourniquets in 25-33% of the hospitals and a number of hospitals used both types (disposable and non-disposable), which could confuse the handling of the tourniquets. A national guideline for usage and cleaning of venepuncture tourniquets is therefore strongly recommended.

Urine Flow Cytometry and Dipstick Analysis in Diagnosing Bacteriuria and Urinary Tract Infections among Adults in the Emergency Department-A Diagnostic Accuracy Trial.

Urinary tract infections (UTIs) are a leading infectious cause of emergency department admission. Early UTI diagnosis is challenging, and a faster, preferably point-of-care urine analysis is necessary. We aimed to evaluate the diagnostic accuracy of urine flow cytometry (UFC) and urine dipstick analysis (UDA) in identifying bacteriuria and UTIs. This study included adults suspected of an infection admitted to three Danish emergency departments. UFC and UDA were the index tests, and urine culture and an expert panel diagnosis were the reference tests. We used logistic regression and receiver operator characteristics curves to find each test's optimal model and cut-off. We enrolled 966 patients and performed urine cultures on 786. Urine culture was positive in 337, and 200 patients were diagnosed with a UTI. The UFC model ruled out bacteriuria in 10.9% with a negative predictive value (NPV) of 94.6% and ruled out UTI in 38.6% with an NPV of 97.0%. UDA ruled out bacteriuria in 52.1% with an NPV of 79.2% and UTI in 52.8% with an NPV of 93.9%. Neither UFC nor UDA performed well in ruling out bacteriuria in our population. In contrast, both tests ruled out UTI safely and in clinically relevant numbers.

The Diagnostic Accuracy of Procalcitonin, Soluble Urokinase-Type Plasminogen Activator Receptors, and C-Reactive Protein in Diagnosing Urinary Tract Infections in the Emergency Department-A Diagnostic Accuracy Study.

Background: Urinary tract infections (UTIs) are a leading bacterial infection in the emergency department (ED). Diagnosing UTIs in the ED can be challenging due to the heterogeneous presentation; therefore, fast and precise tests are needed. We aimed to evaluate the diagnostic precision of procalcitonin (PCT), soluble urokinase plasminogen activator receptors (suPARs), and C-reactive protein (CRP) in diagnosing UTIs, grading the severity of UTIs, and ruling out bacteremia. Methods: We recruited adults admitted to three Danish EDs with suspected UTIs. PCT, suPAR, and CRP were used in index tests, while blood cultures, expert panel diagnosis, and severity grading were used in the reference tests. Logistic regression and area under the receiver operator characteristic curves (AUROCs) were utilized to evaluate the models and determine the optimal cut-offs. Results: We enrolled 229 patients. PCT diagnosed UTI with an AUROC of 0.612, detected severe disease with an AUROC of 0.712, and ruled out bacteremia with an AUROC of 0.777. SuPAR had AUROCs of 0.480, 0.638, and 0.605, while CRP had AUROCs of 0.599, 0.778, and 0.646. Conclusions: The diagnostic performance of PCT, suPAR, or CRP for UTIs or to rule out severe disease was poor. However, PCT can safely rule out bacteremia in clinically relevant numbers in ED patients suspected of UTI.

Serum HER-2 predicts response and resistance to trastuzumab treatment in breast cancer.

BACKGROUND: Serum HER2 (S-HER2) was approved in 2003 by the US Food and Drug Administration (FDA) for monitoring trastuzumab treatment in tissue HER2 positive breast cancer patients. Information of the value of S-HER2 is scarce. We hypothesised that S-HER2 would reflect the clinical effect of trastuzumab. METHODS: We followed 48 patients eligible for trastuzumab treatment for up to 6 years or until death. S-HER2 was measured on an ADVIA Centaur System and S-Trastuzumab was measured by an in-house developed fluorescent enzyme immunoassay system on the ImmunoCap 100. RESULTS: A decrease in S-HER2 of ≥ 20% was correlated to no progression in the disease in 20 out of 21 clinical courses (p<0.0001). An increase in S-HER2 of ≥ 20% was correlated to progression in the disease in 40 out of 44 clinical courses (p<0.0001). Patients with no recurrence after trastuzumab treatment (n=18) had a median S-HER2 concentration of 10.5 µg/L, whereas patients alive with recurrence (n=13) had a median S-HER2 of 20.1 µg/L (p=0.002). Patients who died prompted by recurrence (n=17) had a median S-HER2 of 232.4 µg/L at latest measurement before death (p=<0.0001) compared to patients without recurrence. In two patients with S-HER2 values above 1000 µg/L the concentrations of S-trastuzumab were measured below the target trough concentration in serum of 10 mg/L. CONCLUSIONS: Decreasing values of S-HER2 predicts response to treatment whereas increasing levels predict resistance. S-HER2 above 1000 µg/L warns that standard doses of trastuzumab may be insufficient as reflected by low concentrations of S-trastuzumab.

A Review of Major Danish Biobanks: Advantages and Possibilities of Health Research in Denmark.

Biobank research may lead to an improved understanding of disease etiology and advance personalized medicine. Denmark (population ~5.9 million) provides a unique setting for population-based health research. The country is a rich source of biobanks and the universal, tax-funded healthcare system delivers routinely collected data to numerous registries and databases. By virtue of the civil registration number (assigned uniquely to all Danish citizens), biological specimens stored in biobanks can be combined with clinical and demographic data from these population-based health registries and databases. In this review, we aim to provide an understanding of advantages and possibilities of biobank research in Denmark. As knowledge about the Danish setting is needed to grasp the full potential, we first introduce the Danish healthcare system, the Civil Registration System, the population-based registries, and the interface with biobanks. We then describe the biobank infrastructures, comprising the Danish National Biobank Initiative, the Bio- and Genome Bank Denmark, and the Danish National Genome Center. Further, we briefly provide an overview of fourteen selected biobanks, including: The Danish Newborn Screening Biobank; The Danish National Birth Cohort; The Danish Twin Registry Biobank; Diet, Cancer and Health; Diet, Cancer and Health - Next generations; Danish Centre for Strategic Research in Type 2 Diabetes; Vejle Diabetes Biobank; The Copenhagen Hospital Biobank; The Copenhagen City Heart Study; The Copenhagen General Population Study; The Danish Cancer Biobank; The Danish Rheumatological Biobank; The Danish Blood Donor Study; and The Danish Pathology Databank. Last, we inform on practical aspects, such as data access, and discuss future implications.

Macro-TSH: A Diagnostic Challenge.

INTRODUCTION: Analytical problems should be considered in case of a discrepancy between the results of biochemical tests and the clinical findings. Macro-hormones often artefactually elevate biochemical tests. CASE PRESENTATION: A young male was referred with persistently elevated TSH (148 mIU/L) measured by a sandwich electrochemiluminescence immunoassay, ECLIA (Cobas; Roche, Basel, Switzerland). The patient's complaints were unspecific, and he appeared clinically euthyroid. The plasma levels of free T4 and free T3 were within the normal range, thyroid autoantibodies were negative, and thyroid ultrasonography was normal. During a short trial of thyroid hormone substitution, the level of TSH decreased to near-normal levels, but hyperthyroid symptoms emerged. TSH analysed by a different immunoassay (Architect; Abbott, Chicago, IL, USA) yielded similar results. In addition, serial dilutions were performed showing linearity, without detection of heterophilic antibody interference. Gel filtration chromatography confirmed the presence of macro-TSH. CONCLUSION: The patient harboured macro-TSH, which is a rare condition. The complex binding of TSH to other plasma proteins, most often immunoglobulins, results in elevated plasma TSH. However, the biologically active fraction of TSH is normal, reflected by clinical and biochemical euthyroidism.

Improved diagnostics of infectious diseases in emergency departments: a protocol of a multifaceted multicentre diagnostic study.

BACKGROUND: The major obstacle in prescribing an appropriate and targeted antibiotic treatment is insufficient knowledge concerning whether the patient has a bacterial infection, where the focus of infection is and which bacteria are the agents of the infection. A prerequisite for the appropriate use of antibiotics is timely access to accurate diagnostics such as point-of-care (POC) testing.The study aims to evaluate diagnostic tools and working methods that support a prompt and accurate diagnosis of hospitalised patients suspected of an acute infection. We will focus on the most common acute infections: community-acquired pneumonia (CAP) and acute pyelonephritis (APN). The objectives are to investigate (1) patient characteristics and treatment trajectory of the different acute infections, (2) diagnostic and prognostic accuracy of infection markers, (3) diagnostic accuracy of POC urine flow cytometry on diagnosing and excluding bacteriuria, (4) how effective the addition of POC analysis of sputum to the diagnostic set-up for CAP is on antibiotic prescriptions, (5) diagnostic accuracy of POC ultrasound and ultralow dose (ULD) computerized tomography (CT) on diagnosing CAP, (6) diagnostic accuracy of specialist ultrasound on diagnosing APN, (7) diagnostic accuracy of POC ultrasound in diagnosing hydronephrosis in patients suspected of APN. METHODS AND ANALYSIS: It is a multifaceted multicentre diagnostic study, including 1000 adults admitted with suspicion of an acute infection. Participants will, within the first 24 hours of admission, undergo additional diagnostic tests including infection markers, POC urine flow cytometry, POC analysis of sputum, POC and specialist ultrasound, and ULDCT. The primary reference standard is an assigned diagnosis determined by a panel of experts. ETHICS, DISSEMINATION AND REGISTRATION: Approved by Regional Committees on Health Research Ethics for Southern Denmark, Danish Data Protection Agency and clinicaltrials.gov. Results will be presented in peer-reviewed journals, and positive, negative and inconclusive results will be published. TRIAL REGISTRATION NUMBERS: NCT04661085, NCT04681963, NCT04667195, NCT04652167, NCT04686318, NCT04686292, NCT04651712, NCT04645030, NCT04651244.

Validation of GWAS-Identified Variants for Anti-TNF Drug Response in Rheumatoid Arthritis: A Meta-Analysis of Two Large Cohorts.

We aimed to validate the association of 28 GWAS-identified genetic variants for response to TNF inhibitors (TNFi) in a discovery cohort of 1361 rheumatoid arthritis (RA) patients monitored in routine care and ascertained through the REPAIR consortium and DANBIO registry. We genotyped selected markers and evaluated their association with response to TNFi after 6 months of treatment according to the change in disease activity score 28 (ΔDAS28). Next, we confirmed the most interesting results through meta-analysis of our data with those from the DREAM cohort that included 706 RA patients treated with TNFi. The meta-analysis of the discovery cohort and DREAM registry including 2067 RA patients revealed an overall association of the LINC02549rs7767069 SNP with a lower improvement in DAS28 that remained significant after correction for multiple testing (per-allele ORMeta=0.83, PMeta=0.000077; PHet=0.61). In addition, we found that each copy of the LRRC55rs717117G allele was significantly associated with lower improvement in DAS28 in rheumatoid factor (RF)-positive patients (per-allele ORMeta=0.67, P=0.00058; PHet=0.06) whereas an opposite but not significant effect was detected in RF-negative subjects (per-allele ORMeta=1.38, P=0.10; PHet=0.45; PInteraction=0.00028). Interestingly, although the identified associations did not survive multiple testing correction, the meta-analysis also showed overall and RF-specific associations for the MAFBrs6071980 and CNTN5rs1813443 SNPs with decreased changes in DAS28 (per-allele ORMeta_rs6071980 = 0.85, P=0.0059; PHet=0.63 and ORMeta_rs1813443_RF+=0.81, P=0.0059; PHet=0.69 and ORMeta_rs1813443_RF-=1.00, P=0.99; PHet=0.12; PInteraction=0.032). Mechanistically, we found that subjects carrying the LINC02549rs7767069T allele had significantly increased numbers of CD45RO+CD45RA+ T cells (P=0.000025) whereas carriers of the LINC02549rs7767069T/T genotype showed significantly increased levels of soluble scavengers CD5 and CD6 in serum (P=0.00037 and P=0.00041). In addition, carriers of the LRRC55rs717117G allele showed decreased production of IL6 after stimulation of PBMCs with B burgdorferi and E coli bacteria (P=0.00046 and P=0.00044), which suggested a reduced IL6-mediated anti-inflammatory effect of this marker to worsen the response to TNFi. In conclusion, this study confirmed the influence of the LINC02549 and LRRC55 loci to determine the response to TNFi in RA patients and suggested a weak effect of the MAFB and CNTN5 loci that need to be further investigated.

Elevated zinc concentrations in a 5 months old infant: A case report.

Pre-analytical errors account for the majority of laboratory-associated errors. In a 5 months old infant hospitalised with lung dysfunction due to prematurity, a routine measurement of zinc revealed an unexpected elevated concentration of 20.2 µmol/L (reference interval 10.0 - 19.0 µmol/L) compared to 11.6 µmol/L five days earlier. Zinc measurement was repeated two days later and had further increased to 42.4 µmol/L. Of note, there were no clinical signs of the increased zinc concentrations. Performance data for the zinc analysis (performed by inductively coupled plasma mass spectrometry) was found satisfactory. A thorough review of the patient´s medication and nutrition supplements revealed no relevant zinc content. The blood was obtained through capillary blood sampling, and anything at the skin puncture site containing zinc could therefore potentially contribute to the elevated zinc results. It was investigated if any ointment containing zinc had been applied at the puncture site, which revealed that the mother had applied vitamin E ointment containing zinc-oxide at the infant's heel. A capillary sample obtained from the opposite heel, where no vitamin E ointment had been applied, revealed a zinc concentration of 14.3 µmol/L. In conclusion, pre-analytical contamination with ointments must be considered in case of unexpected measurements from capillary blood.

Rhodopsin in plasma from patients with diabetic retinopathy - development and validation of digital ELISA by Single Molecule Array (Simoa) technology.

BACKGROUND: Diabetic retinopathy (DR) is the most frequent cause of blindness among younger adults in the western world. No blood biomarkers exist to detect DR. Hypothetically, Rhodopsin concentrations in blood has been suggested as an early marker for retinal damage. The aim of this study was therefore to develop and validate a Rhodopsin assay by employing digital ELISA technology, and to investigate whether Rhodopsin concentrations in diabetes patients with DR are elevated compared with diabetes patients without DR. METHODS: A digital ELISA assay using a Simoa HD-1 Analyzer (Quanterix©, Lexington, MA 02421, USA) was developed and validated and applied on a cohort of diabetes patients characterised with (n=466) and without (n=144) DR. RESULTS: The Rhodopsin assay demonstrated a LOD of 0.26ng/l, a LLOQ of 3ng/l and a linear measuring range from 3 to 2500ng/l. Total CV% was 32%, 23%, 19% and 17% respectively at the following Rhodopsin concentrations: 1, 3, 5 and 13ng/l. Recovery was 17%, 34%, 51% and 55% respectively at Rhodopsin concentrations of 2, 10, 50 and 250ng/l. There was no statistically significant difference in the plasma concentration of Rhodopsin between the diabetes patients with or without DR, but significantly increased number of DR patients having concentrations above the LOD. CONCLUSION: We developed and validated a digital ELISA method for quantification of Rhodopsin in plasma but found no statistically significant difference in the plasma concentration of Rhodopsin between diabetes patients with DR compared to diabetes patients without DR, though significantly more DR patients had values above the LOD.

Vejle Diabetes Biobank - a resource for studies of the etiologies of diabetes and its comorbidities.

AIMS: Carefully designed and established biobanks are considered one of the most essential resources to foster biomedical research as they provide cost-effective and rapid access to a vast variety of biological materials and related anthropometrics allowing for testing of various biomarkers as well as numerous original and pertinent bioclinical hypotheses related to human disease etiology and prognosis. The objective of the present study was to present the baseline data, design, and methods used for the establishment of the Vejle Diabetes Biobank. Further aims included assessment of the prevalence of diabetes and quality of diabetes treatment in a specified Danish region. METHODS: The Vejle Diabetes Biobank was established from 2007 to 2010 as a regional Biobank containing blood, DNA, and urine samples from patients with diabetes and a gender- and age-matched control population aged 25-75 years. Anthropometrics were obtained by physical examination, questionnaires, and interviews at the time of inclusion into the Biobank. The cohort was linked to the Danish Civil Registration System, the Danish National Patient Registry, and the Danish National Prescription Registry. RESULTS: In total, 4,255 nondiabetic individuals and 3,320 patients with diabetes were included. Type 2 diabetes (T2D) patients had a higher body mass index (30 kg/m2) than type 1 diabetes (T1D) patients (25 and 26 kg/m2 in women and men, respectively) and control subjects (25 and 27 kg/m2 in women and men, respectively). Fasting levels of plasma triglycerides and blood pressure were higher in T2D patients (1.5 mmol/L and 148/85 mmHg, respectively) compared with T1D patients (0.9 mmol/L and 139/81 mmHg, respectively), whereas glycated hemoglobin (HbA1c), plasma high density lipoprotein, low density lipoprotein, and total cholesterol were lower in T2D patients (51 mmol/mol, 1.2 mmol/L, 2.2 mmol/L, and 4.2 mmol/L, respectively) compared with findings in T1D patients (61 mmol/mol, 1.6 mmol/L, 2.3 mmol/L, and 4.4 mmol/L, respectively). At the time of inclusion into the Biobank, 56% of the T2D patients and 25% of T1D patients had an HbA1c <7% (53 mmol/mol). Only 28% and 34% of the T2D patients, respectively, reached treatment target for blood pressure and lipids. CONCLUSION: The Vejle Diabetes Biobank represents one of the largest open diabetes case-control cohorts in Denmark. The Biobank invites collaborative investigations of diabetes and diabetes complication etiologies as well as studies of prognostic or predictive biomarkers.