Influence of seasonal and operator variations on diagnostic accuracy of lateral flow devices during the COVID-19 pandemic: a systematic review and meta-analysis.

BACKGROUND: Lateral flow tests (LFT) are point-of-care rapid antigen tests that allow isolation and control of disease outbreaks through convenient, practical testing. However, studies have shown significant variation in their diagnostic accuracy. We conducted a systematic review of the diagnostic accuracy of LFTs for the detection of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) to identify potential factors affecting their performance. METHODS: A systematic search of online databases was carried out to identify studies assessing the sensitivity and specificity of LFTs compared with polymerase chain reaction (PCR) tests. Data were extracted and used to calculate pooled sensitivity and specificity. Meta-regression analysis was conducted to identify covariates influencing diagnostic accuracy. RESULTS: In total, 76 articles with 108,820 test results were identified for analysis. Pooled sensitivity and specificity were 72% (95% confidence interval (CI): 0.68-0.76) and 100% (95% CI: 0.99-1.00), respectively. Staff operation of the LFT showed a statistically significant increase in sensitivity (p=0.04) and specificity (p=0.001) compared with self-operation by the test subjects. The use of LFTs in symptomatic patient subgroups also resulted in higher test sensitivity. CONCLUSION: LFTs display good sensitivity and extremely good specificity for SARS-CoV-2 antigen detection; they become more sensitive in patients with symptoms and when performed by trained professionals.

C-reactive protein and albumin association with mortality of hospitalised SARS-CoV-2 patients: A tertiary hospital experience.

OBJECTIVE: The objective was to study hospitalised COVID-19 patients' mortality and intensive care unit (ICU) admission with covariates of interest (age, gender, ethnicity, clinical presentation, comorbidities and admission laboratory findings). METHODS: Logistic regression analyses were performed for patients admitted to University Hospital, University Hospitals Coventry and Warwickshire NHS Trust, between 24 January 2020 - 13 April 2020. RESULTS: There were 321 patients hospitalised. Median age was 73 years and 189 (59%) were male. Ethnicity was divided between Caucasian (77%), and black, Asian, and minority ethnic (BAME) groups (23%). Commonest symptoms were dyspnoea (62.9%), fever (59.1%) and cough (56%). Gastrointestinal symptoms amounted to 11.8%.Forty-four patients (13.7%) received ICU care. ICU male to female ratio was 3:1 (p=0.027; odds ratio (OR) 2.3; 95% confidence interval (CI) 1.1-4.9), BAME (p=0.008; OR 2.5; 95% CI 1.3-4.9), age >65 years (p=0.026; OR 0.28; 95% CI 0.09-0.93), heart disease (p=0.009; OR 0.2; 95% CI 0.1-0.6) and elevated C-reactive protein (CRP; p<0.001; OR 1.004; 95% CI 1.002-1.008) were associated with ICU admission.One-hundred and four patients (32.4%) died. Age >65 years (p=0.011; OR 5; 95% CI 1.6-21.9), neutrophils (p=0.047), neutrophil:lymphocyte ratio (NLR; p=0.028), CRP (p<0.001) and albumin (p=0.002) were associated with mortality. When analysis adjusted for age, CRP (p<0.001; OR 1.006; 95% CI 1.004-1.008) and albumin (p=0.005; OR 0.94; 95% CI 0.90-0.98) remained associated with mortality. CONCLUSIONS: COVID-19 has high mortality. BAME and male patients were associated with ICU admission. High CRP and low albumin (after correcting for age) were associated with mortality.