Diagnostic Accuracy of Clinical Signs and Biochemical Parameters for External Ventricular CSF Catheter-Associated Infection.

Background and Objectives: Few prospective well-designed diagnostic accuracy studies have been performed to study the parameters of infection in patients suspected for external ventricular catheter-associated infection. Our objective was to analyze the diagnostic accuracy of clinical characteristics and biochemical and microbiological parameters in diagnosing external ventricular CSF catheter-associated infection. Methods: From 2014 to 2017, we performed a single-center cohort study in consecutive patients at the intensive care unit who required an external ventricular CSF catheter in the Hague, the Netherlands. CSF was sampled and analyzed daily. Ventricular catheter-associated infection was defined according to the 2017 Infectious Diseases Society of America's Clinical Practice Guidelines. We compared clinical characteristics and biochemical parameters between patients with and without infection from 3 days before to 3 days after the day the CSF sample was collected that grew bacteria. Results: A total of 103 patients were included of whom 15 developed a catheter-associated infection (15%). The median day cultures were positive was 3 days after CSF collection (interquartile range [IQR] +2 to +4). On day 0, none of the tests could differentiate between patients with and without infection. The CSF leukocyte count was increased in patients with ventricular catheter-associated infection as compared with patients without on days +2 and +3. The difference was most prominent on day +2 (1,703 × 106/L [IQR 480-6,296] vs 80 × 106/L [IQR 27-251]; p < 0.001; area under the curve [AUC] 0.87 [95% confidence interval (CI) 0.71-1.00]). Sensitivity for the CSF leukocyte count at a cutoff level >1,000 × 106/L was 67% (95% CI 30-93), and specificity was 100% (95% CI 90-100); the positive predictive value was 100%, and the negative predictive value was 92% (95% CI 83-97). The percentage of polymorphonuclear cells (PMNs) was higher in patients with infection on days +1 and +2 (day +2 89% [IQR 78-94] vs 59% [IQR 39-75]; p < 0.01; AUC 0.91 [95% CI 0.81-1.0]). Discussion: An elevated CSF leukocyte count and increased percentage of PMNs are the strongest indicators for external catheter-associated infections on the days before culture positivity. New CSF markers of drain-associated infection should be studied to enable earlier diagnosis and treatment in patients with an infection and reduce antibiotic treatment in those with no infection. Classification of Evidence: This study provides Class I evidence that in individuals requiring an external ventricular CSF catheter, an elevated CSF leukocyte count and an increased percentage of PMNs are the strongest indicators of catheter-associated infections in the days before CSF culture positivity.

Diagnostic accuracy of four different D-dimer assays: A post-hoc analysis of the YEARS study.

INTRODUCTION: For exclusion of pulmonary embolism (PE) clinical decision rules in combination with a D-dimer assay are applied. Currently available D-dimer assays are not standardized and it is unknown whether these differences have an impact on diagnostic management of suspected PE. Therefore, the aim is to explore differences between D-dimer assays and their impact on diagnostic outcome. METHODS: Data from all patients included in the YEARS study were collected. The YEARS study is a prospective, multicentre, cohort outcome study evaluating 3462 patients with suspected PE in which four different D-dimer assays were applied (Liatest, Innovance, Tinaquant, Vidas). Median D-dimer concentrations were calculated for each D-dimer assay. Sensitivity, specificity, PPV and NPV for detection of PE of all four assays were determined in patients without YEARS items and in those with ≥1 YEARS items (i.e. symptomatic deep vein thrombosis, haemoptysis, and whether PE is the most likely diagnosis). RESULTS: A total of 1323, 1100, 768 and 271 D-dimer concentrations were collected using the Liatest Innovance, Tinaquant and Vidas assay, respectively. Median D-dimer concentrations differed significantly between assays, with lowest values in the Tinaquant assay. In patients without YEARS items using a cutoff level of 1000 ng/mL, the NPV varied from 99,5 to 100%. In patients with ≥1 YEARS items using a 500 ng/mL cutoff, the NPV varied from 97,0 to 100% depending on the assay. CONCLUSIONS: The overall high NPV for all assays demonstrates the clinical value of the D-dimer assay. However, these results confirm differences between D-dimer assays, which have an impact on follow-up imaging. This emphasizes the need for standardization of D-dimer assays.

[Metformin, renal function and lactate: the MetClear Study]. / Metformine, nierfunctie en lactaat: het MetClear-onderzoek.

OBJECTIVE: To map the relation between metformin prescription and renal function in an outpatient setting. To investigate whether there is an association between renal function, metformin concentration and lactate concentration. DESIGN: Pilot for a prospective observational cohort study. METHOD: We included outpatients with diabetes mellitus type 2 who were treated with metformin. At inclusion, we determined the HbA1c, lactate, metformin and creatinine concentrations and the estimated glomerular filtration rate (eGFR). Information on the prescribed dosage of metformin was acquired from patient files. Our primary outcome measure was the number of patients in whom the dose was not adjusted to the renal function. Our secondary outcome measure was the difference in median lactate concentration between patients with a normal (≤ 2.5 mg/l) and an increased (> 2.5 mg/l) metformin concentration. RESULTS: Eighty-eight patients were included, 12 (14%) of whom had an eGFR ≤ 30, 31 (36%) an eGFR of 30-50 and 44 (50%) an eGFR > 51 ml/min/1.73 m2. In 27 (31%) of all patients, the daily dose of metformin exceeded the dose recommended in the practice guidelines. The 28 patients with an increased metformin concentration had a significantly higher median lactate concentration: 2.3 mmol/l compared to 1.5 mmol/l for the 60 patients with a normal metformin concentration (p < 0.0001). CONCLUSION: Our study shows that in outpatient practice, the metformin dose is not sufficiently adjusted to a reduced renal function in 31% of the patients. The accumulation of metformin appears to be associated with an increased lactate concentration and a reduced renal function. Extra attention to the dose of metformin in reduced renal clearance is therefore recommended.

Cost-effectiveness analysis of cardiovascular risk factor screening in women who experienced hypertensive pregnancy disorders at term.

OBJECTIVES: To assess the cost-effectiveness of post-partum screening on cardiovascular risk factors and subsequent treatment in women with a history of gestational hypertension or pre-eclampsia at term. STUDY DESIGN: Two separate Markov models evaluated the cost-effectiveness analysis of hypertension (HT) screening and screening on metabolic syndrome (MetS), respectively, as compared to current practice in women with a history of term hypertensive pregnancy disorders. Analyses were performed from the Dutch health care perspective, using a lifetime horizon. One-way sensitivity analyses and Monte Carlo simulation evaluated the robustness of the results. RESULTS: Both screening on HT and MetS in women with a history of gestational hypertension or pre-eclampsia resulted in increase in life expectancy (HT screening 0.23year (95% CI -0.06 to 0.54); MetS screening 0.14years (95% CI -0.16 to 0.45)). The gain in QALYs was limited, with HT screening and MetS screening generating 0.04 QALYs (95% CI -0.12 to 0.20) and 0.03 QALYs (95% CI -0.14 to 0.19), resulting in costs to gain one QALY of €4228 and €28,148, respectively. Analyses for uncertainty showed a chance of 74% and 75%, respectively, that post-partum screening is cost-effective at a threshold of €60,000/QALY. CONCLUSIONS: According to the available knowledge post-partum screening on cardiovascular risk factors and subsequent treatment in women with a history of gestational hypertension or pre-eclampsia at term is likely to be cost-effective.

Cardiovascular risk factors in women who had hypertensive disorders late in pregnancy: a cohort study.

OBJECTIVE: The purpose of this study was to determine cardiovascular risk factors in women with a history of hypertensive pregnancy disorders at term (HTP) 2.5 years after pregnancy. STUDY DESIGN: In a multicenter cohort study in The Netherlands from June 2008 through November 2010, cardiovascular risk factors were compared between women with a history of HTP (HTP cohort, n = 306) and women with a history of normotensive pregnancies at term (NTP cohort, n = 99). HTP women had participated in a randomized, longitudinal trial assessing the effectiveness of induction of labor in women with hypertensive pregnancy disorders at term. All women were assessed 2.5 years after pregnancy for blood pressure, anthropometrics, glucose, glycosylated hemoglobin, insulin, homeostatic model assessment score, total cholesterol, high-density lipoprotein cholesterol, triglycerides, high-sensitivity C-reactive protein, and microalbumin and metabolic syndrome. RESULTS: After a mean follow-up period of 2.5 years, hypertension (HTP, 34%; NTP, 1%; P < .001) and metabolic syndrome (HTP, 25%; NTP, 5%; P < .001) were more prevalent in HTP women compared with NTP women. HTP women had significantly higher systolic and diastolic blood pressure, higher body mass index, and higher waist circumference. Glucose, glycosylated hemoglobin, insulin, homeostatic model assessment score, total cholesterol, triglycerides, and high-sensitivity C-reactive protein levels were significantly higher and high-density lipoprotein cholesterol was significantly lower in HTP women. CONCLUSION: In women with a history of HTP, hypertension and metabolic syndrome are more common, and they have higher levels of biochemical cardiovascular risk factors 2.5 years after pregnancy.