Estimating the effect of COVID-19 vaccination and prior infection on Ct values as a proxy of SARS-CoV-2 viral load.

Objectives: SARS-CoV-2 viral load could be an important parameter for transmission potential. Here, we use RT-qPCR cycle threshold (Ct) values as a proxy for viral load. We assess the effect of COVID-19 vaccination and prior infection status on Ct value, while accounting for the virus variant.

Inconsistency in ferritin reference intervals across laboratories: a major concern for clinical decision making.

Objectives: Iron deficiency anemia is a significant global health concern, diagnosed by measuring hemoglobin concentrations in combination with plasma ferritin concentration. This study investigated the variability in ferritin reference intervals among laboratories in the Netherlands and examined how this affects the identification of iron-related disorders.

Methods: Ferritin reference intervals from 52 Dutch ISO15189-certified medical laboratories were collected.

Description of a nationwide structure for monitoring nosocomial outbreaks of (highly resistant) microorganisms in the Netherlands: characteristics of outbreaks in 2012-2021.

Background: Before 2012, established national surveillance systems in the Netherlands were not able to provide a timely, comprehensive epidemiological view on nosocomial outbreaks. The Healthcare-associated Infections and AntiMicrobial Resistance Monitoring Group (SO-ZI/AMR) was initiated in 2012 for timely national nosocomial outbreak monitoring and risk assessment. This paper aims to describe the achievements of the SO-ZI/AMR by presenting characteristics of outbreaks reported in 2012-2021.

Higher risk of SARS-CoV-2 Omicron BA.4/5 infection than of BA.2 infection after previous BA.1 infection, the Netherlands, 2 May to 24 July 2022.

BackgroundIn summer 2022, SARS-CoV-2 Omicron BA.5 became dominant in Europe. In vitro studies have shown a large reduction of antibody neutralisation for this variant.

Protection of COVID-19 vaccination and previous infection against Omicron BA.1, BA.2 and Delta SARS-CoV-2 infections.

Given the emergence of the SARS-CoV-2 Omicron BA.1 and BA.2 variants and the roll-out of booster COVID-19 vaccination, evidence is needed on protection conferred by primary vaccination, booster vaccination and previous SARS-CoV-2 infection by variant.

Shorter serial intervals in SARS-CoV-2 cases with Omicron BA.1 variant compared with Delta variant, the Netherlands, 13 to 26 December 2021.

The SARS-CoV-2 Omicron variant has a growth advantage over the Delta variant because of higher transmissibility, immune evasion or shorter serial interval. Using S gene target failure (SGTF) as indication for Omicron BA.1, we identified 908 SGTF and 1,621 non-SGTF serial intervals in the same period.

Increased risk of infection with SARS-CoV-2 Omicron BA.1 compared with Delta in vaccinated and previously infected individuals, the Netherlands, 22 November 2021 to 19 January 2022.

Infections with the Omicron SARS-CoV-2 variant are rapidly increasing worldwide. Among 174,349 SARS-CoV-2-infected individuals (≥ 12 years), we observed an increased risk of S gene target failure, predictive of the Omicron variant, in vaccinated (odds ratio (OR): 3.6; 95% confidence interval (CI): 3.

Effectiveness of professional and patient-oriented strategies in reducing vitamin D and B12 test ordering in primary care: a cluster randomised intervention study.

Background: Vitamin tests are increasingly ordered by GPs, but a clinical and evidence-based indication is often lacking. Harnessing technology (that is, decision support tools and redesigning request forms) have been shown to reduce vitamin requests.

Aim: To investigate whether the number of vitamin tests may be reduced by providing a multi-level intervention programme based on training, monitoring, and feedback.

Comparative genomics of ESBL-producing Escherichia coli (ESBL-Ec) reveals a similar distribution of the 10 most prevalent ESBL-Ec clones and ESBL genes among human community faecal and extra-intestinal infection isolates in the Netherlands (2014-17).

Introduction: The human gut microbiota is an important reservoir of ESBL-producing Escherichia coli (ESBL-Ec). Community surveillance studies of ESBL-Ec to monitor circulating clones and ESBL genes are logistically challenging and costly.

Objectives: To evaluate if isolates obtained in routine clinical practice can be used as an alternative to monitor the distribution of clones and ESBL genes circulating in the community.

Nitrofurantoin Failure in Elderly Men: A Retrospective Observational Study.

Urinary tract infections in the elderly are common. Treatment with nitrofurantoin in men may not be sufficient if concomitant tissue involvement is present, resulting in treatment failure. The aim of this study is to determine the prevalence of nitrofurantoin failure in the elderly, and to assess the effect of gender and age.

Folate reference interval estimation in the Dutch general population.

Background: Folate functions as an enzyme co-factor within the one-carbon metabolic pathway, providing key metabolites required for DNA synthesis and methylation. Hence, insufficient intake of folate can negatively affect health. As correct interpretation of folate status is dependent on a well-established reference interval, we set out to perform a new estimation following the restandardization of the Roche folate assay against the international folate standard.

Point-of-care C-reactive protein to assist in primary care management of children with suspected non-serious lower respiratory tract infection: a randomised controlled trial.

Background: Overprescription of antibiotics for lower respiratory tract infections (LRTIs) in children is common, partly due to diagnostic uncertainty, in which case the addition of point-of-care (POC) C-reactive protein (CRP) testing can be of aid.

Aim: To assess whether use of POC CRP by the GP reduces antibiotic prescriptions in children with suspected non-serious LRTI.

Design & Setting: An open, pragmatic, randomised controlled trial in daytime general practice and out-of-hours services.

International definition of a point-of-care test in family practice: a modified e-Delphi procedure.

Background: The use of point-of-care tests (POCTs) in family practice is increasing, and the term POCT is often used in medical literature and clinical practice. Yet, no widely supported definition by several professional fields exists.

Objective: To reach consensus on an international definition of a POCT in family practice.

Influence of point-of-care C-reactive protein testing on antibiotic prescription habits in primary care in the Netherlands.

Background: Bacterial resistance to antibiotics represents a serious global challenge that is associated with high morbidity and mortality. One of the most important causes of this threat is antibiotic overuse. The Dutch College of General Practitioners (DCGP) recommends the use of point-of-care (POC) testing for C-reactive protein (CRP) in two guidelines ('Acute Cough' and 'Diverticulitis') to achieve a more sensible prescription pattern of antibiotics.

The added value of C-reactive protein measurement in diagnosing pneumonia in primary care: a meta-analysis of individual patient data.

Background: C-reactive protein (CRP) is increasingly being included in the diagnostic work-up for community-acquired pneumonia in primary care. Its added diagnostic value beyond signs and symptoms, however, remains unclear. We conducted a meta-analysis of individual patient data to quantify the added value of CRP measurement.

Evaluation of the performance of a point-of-care method for total and differential white blood cell count in clozapine users.

Introduction: We evaluated the performance of the HemoCue WBC DIFF, a point-of-care device for total and differential white cell count, primarily to test its suitability for the mandatory white blood cell monitoring in clozapine use.

Method: Leukocyte count and 5-part differentiation was performed by the point-of-care device and by routine laboratory method in venous EDTA-blood samples from 20 clozapine users, 20 neutropenic patients, and 20 healthy volunteers. From the volunteers, also a capillary sample was drawn.

Analysis of recruitment in a pragmatic observational study on C-reactive protein point-of-care testing in primary care.

Introduction: Failure to recruit all eligible study patients can lead to biased results. Little is known on selective patient recruitment in studies on implementation of diagnostic devices.

Objectives: The aim of this observational study was to measure recruitment of patients in an implementation study in primary care on use of point-of-care (POC) C-reactive protein (CRP) and to evaluate recruitment bias and its impact on the study endpoint.

C-reactive protein point-of-care testing and associated antibiotic prescribing.

Background: In clinical trials, the potential of point-of-care (POC) C-reactive protein (CRP) tests was demonstrated in decreasing antibiotic prescribing in adults with acute cough in general practice, but effects of implementation are unknown.

Objective: To determine the overall effect of POC CRP testing on antibiotic prescribing rate in general practice.

Methods: In an observational study, GPs were instructed to use POC CRP in adults with acute cough following current guidelines.

External Validation of Prediction Models for Pneumonia in Primary Care Patients with Lower Respiratory Tract Infection: An Individual Patient Data Meta-Analysis.

Background: Pneumonia remains difficult to diagnose in primary care. Prediction models based on signs and symptoms (S&S) serve to minimize the diagnostic uncertainty. External validation of these models is essential before implementation into routine practice.

Instructions for clinical and biomarker monitoring in the Summary of Product Characteristics (SmPC) for psychotropic drugs: Overview and applicability in clinical practice.

The Summary of Product Characteristics (SmPC) for psychotropic drugs includes instructions for clinical and biomarker monitoring intended to optimise effectiveness and minimise harm. The present study evaluated which monitoring instructions are given in the SmPCs, and assessed whether instructions are informative enough to be applicable in clinical practice. Monitoring instructions were collected from complete SmPCs for psychotropic drugs (n=70).

Serum biomarkers for the early diagnosis of TIA: The MIND-TIA study protocol.

Background: A Transient Ischaemic Attack (TIA) bears a high risk of a subsequent ischaemic stroke. Adequate diagnosis of a TIA should be followed immediately by the start of appropriate preventive therapy, including antiplatelets. The diagnosis of a TIA based on symptoms and signs only is notoriously difficult and biomarkers of brain ischaemia might improve the recognition, and target management and prognosis of TIA patients.

Analytical performance, agreement and user-friendliness of six point-of-care testing urine analysers for urinary tract infection in general practice.

Objective: Various point-of-care testing (POCT) urine analysers are commercially available for routine urine analysis in general practice. The present study compares analytical performance, agreement and user-friendliness of six different POCT urine analysers for diagnosing urinary tract infection in general practice.

Setting: All testing procedures were performed at a diagnostic centre for primary care in the Netherlands.