Prevalence and determinants of serum antibodies to SARS-CoV-2 in the general population of the Gardena valley.

Estimating the spread of SARS-CoV-2 infection in communities is critical. We surveyed 2244 stratified random sample community members of the Gardena valley, a winter touristic area, amidst the first expansion phase of the COVID-19 pandemic in Europe. We measured agreement between Diasorin and Abbott serum bioassay outputs and the Abbott optimal discriminant threshold of serum neutralisation titres with recursive receiver operating characteristic curve. We analytically adjusted serum antibody tests for unbiased seroprevalence estimate and analysed the determinants of infection with non-response weighted multiple logistic regression. SARS-CoV-2 seroprevalence was 26.9% (95% CI 25.2-28.6) by June 2020. The bioassays had a modest agreement with each other. At a lower threshold than the manufacturer's recommended level, the Abbott assay reflected greater discrimination of serum neutralisation capacity. Seropositivity was associated with place and economic activity, not with sex or age. Symptoms like fever and weakness were age-dependent. SARS-CoV-2 mitigation strategies should account for context in high prevalence areas.

Comparison of the Results of Proficiency Testing in Seven Medical Laboratories - a Benchmark Project to Define a Uniform Key Performance Indicator.

BACKGROUND: In medical laboratories, it is mandatory to ensure the analytical quality of the measurement procedures by proficiency testing (PT). The aim of this study was to evaluate whether the PT results of seven medical laboratories in South Tyrol - as a measure of the analytical performance - were different. METHODS: As a measure for the analytical performance of the individual laboratories, we used the PT results (RIQAS, Randox international quality assessment scheme) of one year for 34 analytes. We calculated annual 'total scores' of each analyte for all participating laboratories and compared them statistically. RESULTS: In 2018, there was a highly significant difference between the seven laboratories in the 'total scores' for the 34 analytes (p < 0.001). The laboratories had a 'cumulative, annual total score' of 75 - 91% of the maximum achievable values. Essentially, two groups could be distinguished. Laboratories 1 - 3 achieved better results (90 - 91%) than laboratories 4 - 7 (77 - 82%). In particular, the non-participation of the laboratories 4 - 7 in several PT cycles in 2018 and the registration in the wrong homogeneous group for some analytes in the laboratories 4 and 5 seem to be responsible for the worse results. CONCLUSIONS: The analytical performance as assessed by the PT results was different across the seven participating laboratories of the South Tyrolean Medical Service. Based on our study results, we defined a uniform key performance indicator for the seven laboratories with a limit value for the 'cumulative, annual total score' of > 80%.

Effect of a liberal versus a restrictive pre-donation blood pressure policy on whole-blood donor adverse reactions.

BACKGROUND AND OBJECTIVES: The role of pre-donation blood pressure (BP) as independent contributor to post-donation vasovagal reactions (VVRs) is still debated. Differences between a liberal (i.e., inclusion of hypotensive donors) and a restrictive policy (i.e., not accepting hypotensive donors) should be investigated. This study aims to investigate the consequences of a liberal policy in development of VVRs after whole-blood donations. MATERIALS AND METHODS: We compared the incidence of VVRs between 2015 (restrictive policy) and 2016 (liberal policy) and the associated risk factors. We evaluated respectively 22 789 vs. 21 676 blood donations obtained from 18 001 blood donors (12 501 donated in both years). RESULTS: Comparing the results we obtained between 2015 and 2016, donations showed an overlap of the cohorts. Two hundred fifteen VVRs (incidence rate 0·48%) were observed, 104 (0·46%) of which in 2015, and 111 (0·51%) in 2016. A preliminary univariate analysis showed that donors with systolic BP <110 mm Hg had a two-fold risk of VVRs compared to normotensive donors (VVR/donation rate of 0·99% vs. 0·46%; P = 0·001). The subsequent multivariable logistic regression model showed that VVRs were highly associated with weight, site of collection, age and number of donations, excluding a role for systolic and diastolic BP. CONCLUSION: A liberal pre-donation BP policy seems to be safe for blood donors. Our analysis confirms that older donors with higher body-weight who already had donated blood are unlikely to experience VVRs.

Inborn-like errors of metabolism are determinants of breast cancer risk, clinical response and survival: a study of human biochemical individuality.

Breast cancer remains a leading cause of morbidity and mortality worldwide yet methods for early detection remain elusive. We describe the discovery and validation of biochemical signatures measured by mass spectrometry, performed upon blood samples from patients and controls that accurately identify (>95%) the presence of clinical breast cancer. Targeted quantitative MS/MS conducted upon 1225 individuals, including patients with breast and other cancers, normal controls as well as individuals with a variety of metabolic disorders provide a biochemical phenotype that accurately identifies the presence of breast cancer and predicts response and survival following the administration of neoadjuvant chemotherapy. The metabolic changes identified are consistent with inborn-like errors of metabolism and define a continuum from normal controls to elevated risk to invasive breast cancer. Similar results were observed in other adenocarcinomas but were not found in squamous cell cancers or hematologic neoplasms. The findings describe a new early detection platform for breast cancer and support a role for pre-existing, inborn-like errors of metabolism in the process of breast carcinogenesis that may also extend to other glandular malignancies. Statement of Significance: Findings provide a powerful tool for early detection and the assessment of prognosis in breast cancer and define a novel concept of breast carcinogenesis that characterizes malignant transformation as the clinical manifestation of underlying metabolic insufficiencies.