Performance evaluation of the Access anti-HBc Total assay on the DxI 9000 Access Immunoassay Analyzer.

This study evaluated the diagnostic and analytical performances of the Access anti-HBc Total assay on the DxI 9000 Access Immunoassay System (Beckman Coulter Inc.). The multicenter study involved both prospective and retrospective sample collection from non-selected blood donors, hospitalized patients, or presumed anti-HBc Total positive individuals. Fresh/previously-frozen samples were tested with the Access and comparator assays to determine concordance; discrepant samples were tested with a second CE-marked assay. Among the 5983 non-selected fresh blood donor samples deemed anti-HBc Total negative, clinical specificity of the Access assay was 99.58% (95%CI: 99.38-99.72%). Clinical specificity was 99.27% (97.37-99.80%) among 273 anti-HBc Total negative hospitalized patient samples. Clinical sensitivity on 450 anti-HBc Total positive samples was 99.78% (98.75-99.96%). Evaluation in seroconversion panels revealed an average 1.4-day earlier detection versus a comparator assay. The Access assay demonstrated excellent clinical and analytical performances comparable to existing CE-marked anti-HBc Total assays. NCT04904835.

Performance evaluation of the Access HBsAg and Access HBsAg confirmatory assays on the DxI 9000 Access Immunoassay Analyzer.

Introduction: This study evaluated the clinical and analytical performances of the Access HBsAg and the Access HBsAg Confirmatory assays on the DxI 9000 Access Immunoassay Analyzer (Beckman Coulter, Inc.). Materials and methods: Diagnostic specificity and sensitivity of the Access HBsAg and Access HBsAg Confirmatory assays were evaluated by comparing the Access assays to the final HBsAg sample status determined using the Architect, PRISM, or Elecsys HBsAg assays, along with Architect or PRISM HBsAg Confirmatory assays. Imprecision, sensitivity on seroconversion panels, analytical sensitivity on WHO, and recognition of HBV variants were also evaluated. Results: A total of 7534 samples were included in the analysis (6047 blood donors, 1032 hospitalized patients, 455 positive patients' samples). Access HBsAg assay sensitivity and specificity were at 100.00% (99.19-100.0) and 99.92% (99.82-99.97), respectively. Sensitivity of Access HBsAg Confirmatory assay was 100.00% (99.21-100.0) on the 464 HBsAg positive samples. The use of a high positive algorithm for the Access HBsAg assay, wherein samples with S/CO ≥ 100.00 were considered positive without requiring repeat or confirmatory testing, was successfully evaluated with all 450 specimens with S/CO greater than 100.00 (sensitivity 100.00%; 99.19-100.0). Access HBsAg assay demonstrated good analytical performance, equivalent recognition of seroconversion panels compared to Architect assay, and an analytical sensitivity between 0.022 and 0.025 IU/mL. All HBV genotypes, subtypes and mutants were well detected without analytical sensitivity loss. Conclusion: Access HBsAg and Access HBsAg Confirmatory assays demonstrated robust performances. They provide low samples volume requirements and a simplified process, no systematic retesting for high positive samples.

Procalcitonin guidance in patients with lower respiratory tract infections: a systematic review and meta-analysis.

Although effective for bacterial lower respiratory tract infections (LRTIs), antibiotic treatment is often incorrectly prescribed for non-bacterial LRTIs. Procalcitonin has emerged as a promising biomarker to diagnose bacterial infections and guide antibiotic treatment decisions. As part of a regulatory submission to the U.S. Food and Drug Administration, this systematic review and meta-analysis summarizes the effects of procalcitonin-guided antibiotic stewardship on antibiotic use and clinical outcomes in adult LRTI patients. PubMed and the Cochrane Database of Systematic Reviews were searched for English-language randomized controlled trials published between January 2004 and May 2016. Random and fixed effects meta-analyses were performed to study efficacy (initiation of antibiotics, antibiotic use) and safety (mortality, length of hospital stay). Eleven trials were retained, comprising 4090 patients. Procalcitonin-guided patients had lower odds of antibiotic initiation (odds ratio: 0.26; 95% confidence interval [CI]: 0.13-0.52) and shorter mean antibiotic use (weighted mean difference: -2.15 days; 95% CI: -3.30 to -0.99) compared to patients treated with standard care. Procalcitonin use had no adverse impact on mortality (relative risk: 0.94; 95% CI: 0.69-1.28) and length of hospital stay (weighted mean difference: -0.15 days; 95% CI: -0.60 to 0.30). Procalcitonin guidance reduces antibiotic initiation and use among adults with LRTIs with no apparent adverse impact on length of hospital stay or mortality.

Efficacy and Safety of Procalcitonin Guidance in Patients With Suspected or Confirmed Sepsis: A Systematic Review and Meta-Analysis.

OBJECTIVE: Sepsis is a leading cause of mortality in noncoronary ICUs. Although immediate start of antibiotics reduces sepsis-related mortality, antibiotics are often administered for too long, leading to suboptimal treatment and, importantly, contributes to antimicrobial resistance. Prior literature suggests that procalcitonin correlates with infection and thus may help to guide the decision on when to stop antibiotic treatment. This study was conducted as part of a regulatory submission to the U.S. Food and Drug Administration and aimed to summarize the evidence of procalcitonin guidance on efficacy and safety outcomes in adult patients with sepsis. DATA SOURCES: PubMed and the Cochrane Database of Systematic Reviews. STUDY SELECTION: English-language randomized controlled trials evaluating procalcitonin use among adult patients with suspected or confirmed sepsis published between January 2004 and May 2016. DATA EXTRACTION: Inverse-variance weighting fixed and random effects meta-analyses were performed on the following efficacy and safety endpoints: antibiotic duration, all-cause mortality, and length of ICU stay. Two reviewers independently extracted data elements from identified studies and measured risk of bias with the Cochrane Risk of Bias Tool. DATA SYNTHESIS: From a total of 369 potentially eligible articles, 10 randomized controlled trials containing 3,489 patients were used for analysis. Procalcitonin-guided patients had shorter antibiotics duration compared with controls (7.35 vs. 8.85 d; weighted mean difference, -1.49 d; 95% CI, -2.27 to -0.71; p < 0.001). Procalcitonin use had no adverse impact on mortality (risk ratio, 0.90; 95% CI, 0.79-1.03; p = 0.114) and length of ICU stay (11.09 d vs. 11.91 d; weighted mean difference, -0.84 d; 95% CI, -2.52 to 0.84; p = 0.329). CONCLUSIONS: In adult patients with suspected or confirmed sepsis, procalcitonin guidance reduces antibiotics duration with no observed adverse effects on patient outcomes.