Clinical usefulness of fully automated chemiluminescent immunoassay for quantitative antibody measurements in COVID-19 patients.

Since December 2019, we have been in the battlefield with a new threat to the humanity, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), characterized by viral pneumonia. It may be asymptomatic or cause various symptoms, ranging from flu-like symptoms to acute respiratory distress syndrome and eventually death. At present, the only reliable test for COVID-19 diagnosis is quantitative reverse transcriptase-polymerase chain reaction. Assessing the immune response against SARS-CoV-2 could increase the detection sensitivity of infected population. Hereby, we report the performances of a fully automated chemiluminescent immunoassay (CLIA) on 276 serum samples. One hundred samples obtained from COVID-19 negative subjects (COVID-19 free) were analyzed to evaluate the diagnostic specificity of antibody (Ab) detection. Thereafter, 176 samples obtained from 125 patients with confirmed COVID-19 (COVID-19 patients) were selected to assess the diagnostic sensitivity of the CLIA. All samples were analyzed on MAGLUMI 800 platform. All COVID-19 free samples had Ab levels below the cutoff values. Hence, the diagnostic specificity was estimated at 100% (95% confidence interval [CI] = 96.3-100.0; positive predictive value = 100%). By the 18th day from the onset of symptoms, we reached an optimal diagnostic sensitivity (more than 95.0%) In fact, the diagnostic sensitivity increased over time and between 15 and 25 days after symptoms onset, reached 95.5% (95% CI = 84.9-99.2). The new automated CLIA analyzer appeared to be a robust and reliable method to measure specific Ab against COVID-19 at high throughput. Our data suggest that combining Ab and nucleic acid detection could increase diagnostic sensitivity.

Outcome of Patients with Surgical Site Infection after Craniotomy.

Background: The management of surgical site infection (SSI) after craniotomy remains challenging with few existing recommendations. Patients and Methods: We reviewed the medical files of patients who underwent surgery between 2009 and 2018 to manage infection after craniotomy at our tertiary hospital. The Cox proportional hazards model and the Renyi test were used to investigate the association between relapse or all-cause mortality and selected variables. We compared infections with and without intra-cranial involvement using the Fisher test and the Wilcoxon rank sum test. Results: Seventy-seven episodes of infection were identified in 58 patients. The proportion of relapse was estimated to be 32.2% (± standard deviation [SD] 6.9) at five years. Intra-cranial infection was present in 15.6% of the cases (n = 12). Bone flap was removed in the majority of cases (93.5%) and the overall median duration of antibiotic therapy was six weeks (interquartile range [IQR] 6-12 weeks). Staphylococcus aureus was associated with a higher risk of relapse (p = 0.037). The administration of parenteral antibiotic agents (p = 0.012) and bone flap removal (p = 0.0051) were correlated with less relapse. In contrast, immunosuppressive drug use and radiotherapy were correlated with a higher risk of relapse (p = 0.014 and p = 0.031, respectively) and a higher all-cause mortality (p = 0.0093 and p < 0.0001, respectively). We found no difference between infections with and without intra-cranial involvement. Conclusions: Bone flap removal and parenteral antibiotic agents remain important in the management of SSI after craniotomy and were associated with less relapse in our study. More studies are needed to better determine the optimal treatment of this infection.