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Background: CD4 measurement is pivotal in the management of advanced HIV disease. VISITECT® CD4 Advanced Disease (AccuBio Limited, Alva, UK; VISITECT) is an instrument-free, point-of-care, semi-quantitative test allowing visual identification of a CD4 ≤200 cells/µl, or >200 cells/µl from finger-prick or venous blood., Methods: As part of a diagnostic accuracy study of FUJIFILM SILVAMP TB LAM (clinicaltrials.gov: NCT04089423), people living with HIV of ≥18 years old were prospectively recruited in seven countries from outpatient departments if a tuberculosis symptom was present, and from inpatient departments. Participants provided venous blood for CD4 measurement using flow cytometry (reference standard) and finger-prick blood for VISITECT (index text), performed at point-of-care. Sensitivity, specificity, and positive and negative predictive values of VISITECT to determine a CD4 ≤200 cells/µl were evaluated., Results: Among 1604 participants, the median flow cytometry CD4 was 367 (IQR 128-626) cells/µl and 521 (32.5%) had a CD4 ≤200 cells/µl. VISITECT sensitivity was 92.7% (483/521, 95% CI 90.1-94.7%) and specificity was 61.4% (665/1083, 95% CI 58.4-64.3%). For participants with a CD4 between 0-100, 101-200, 201-300, 301-500, and >500 cells/µl, VISITECT misclassified 4.5% (95% CI 2.5-7.2%), 12.5 (95% CI 8.0-18.2%), 74.1% (95% CI 67.0-80.5%), 48.0% (95% CI 42.5-53.6%), and 22.6% (95% CI 19.3-26.3%), respectively., Conclusions: VISITECT's sensitivity, but not specificity, met the World Health Organization's minimal sensitivity and specificity threshold of 80% for point-of-care CD4 tests. VISITECT's quality needs to be assessed and its accuracy optimized. VISITECT´s utility as CD4 triage test should be investigated., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Objectives: Prosthesis-patient mismatch (PPM) after surgical aortic valve replacement (SAVR) for severe aortic valve stenosis (AVS) is common, but less common after transcatheter aortic valve replacement (TAVR) in patients considered at high risk for death after surgery. The objectives of this study were to determine incidence and clinical effect of PPM after SAVR and TAVR in a primarily low-risk patient group., Methods: Patients 70 years or older with severe isolated AVS, regardless of predicted operative mortality risk, were consecutively randomized 1:1 to TAVR using a self-expandable bioprosthesis (n = 145) or SAVR (n = 135). Post-procedure PPM was graded after 3 months as follows: Not present-mild, if indexed effective orifice area (iEOA) >0.85 cm 2 /m 2 , moderate, if 0.65 cm 2 /m 2 < iEOA ≤ 0.85 cm 2 /m 2 and severe, if iEOA ≤0.65 cm 2 /m 2 . Outcomes were major adverse cardiac and cerebrovascular events (MACCE, e.g. composite rate of all-cause death, stroke, myocardial infarction or valve reintervention), cardiac-related hospitalizations and New York Heart Association (NYHA) functional class after 2 years., Results: The incidence and the severity of PPM were significantly lower after TAVR compared with SAVR (severe, moderate, none-mild 14.0, 35.5, 50.4 vs 33.9, 36.7, 29.4%; P<0.001). PPM resulted in similar higher mean valve gradients at 3 months for both groups. Baseline characteristics related to severe PPM were younger age, absence of diabetes mellitus, lower mortality-risk score for TAVR, and younger age and higher body mass index for SAVR. At 2 years, there were numerical but no statistically significant differences between both TAVR and SAVR patients with severe and no severe PPM for MACCE (0.0 vs 12.8% for TAVR; P = 0.13, and 13.5 vs 7.0% for SAVR; P = 0.27), number of cardiac-related hospitalizations (mean ± standard deviation 0.4 ± 0.6 vs 0.6 ± 0.8; P = 0.23, and 0.4 ± 0.8 vs 0.5 ± 0.9; P = 0.70) and NYHA functional class (Class I/II/III/IV: 64.7/29.4/5.9/0.0 vs 62.1/34.7/3.2/0.0%, respectively; P = 0.91, and 71.4/25.7/2.9/0.0 vs 72.9/22.9/4.3/0.0%, respectively; P = 0.92)., Conclusions: The incidence of PPM was lower and less severe after TAVR compared with SAVR in intermediate- and low-risk patients with severe AVS. There were no significant differences in MACCE, cardiac-related hospitalizations or NYHA class after 2 years for patients with versus those without severe PPM., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

The performance characteristics of the Tandem-MP Ostase assay, a new microplate immunoassay for bone-specific alkaline phosphatase (bone ALP; EC 3.1.3.1) in human sera, are described. Bone ALP is bound to streptavidin-coated microwells by a single biotinylated anti-bone ALP monoclonal antibody. Antigen is detected by the addition of p-nitrophenyl phosphate. The assay is performed at room temperature in <90 min. Imprecision was 2.3-6.1% with a detection limit of 0.6 microg/L. Method comparison of bone ALP measurements with the Tandem-MP Ostase assay and the mass-based Tandem-R Ostase assay (n = 285) indicated regression statistics of Tandem-MP Ostase = 1.03 Tandem-R Ostase + 0.22 microg/L, S(y/x) = 4.0 microg/L, r = 0.97. Serum bone ALP values in apparently healthy men and in pre- and postmenopausal women were also similar between the two Ostase assay formats. Liver ALP reactivity determined using the slope and heat inactivation methods was similar in both Ostase assays. Liver ALP reactivity ranged from 3 microg/L (heat inactivation) to 6 microg/L (slope method) per 100 U/L of liver ALP activity, whereas bone ALP reactivity was 37 microg/L per 100 U/L of bone ALP activity, indicating a liver ALP relative reactivity of 8.1-16.2%. Similar results were obtained with the Alkphase-B bone ALP immunoassay. The Tandem-MP Ostase bone ALP assay demonstrated increased concentrations of serum bone ALP in conditions where bone metabolism is increased and showed a rapid, temporal decrease in serum bone ALP in Paget disease patients on bisphosphonate therapy. In conclusion, the Tandem-MP Ostase assay for serum bone ALP is a rapid, simple, robust nonisotopic alternative to the Tandem-R Ostase immunoradiometric assay that provides an accurate and sensitive assessment of bone turnover.