Background: Mild traumatic brain injury (mTBI) management in emergency departments is a complex process involving clinical evaluation, laboratory testing, and computerized tomography (CT) scanning. Protein S100B has proven to be a useful blood biomarker for early evaluation of mTBI, as it reduces the required CT scans by one-third. However, to date, the ability of S100B to identify positive abnormal findings in the CT scans of patients suffering from mTBI caused by ski practice has not been investigated. Thus, the primary aim of this study was to investigate the diagnostic performance of S100B as an mTBI management biomarker in patients with ski-related mTBI. Materials and Methods: One hundred and thirty adult mTBI patients presenting to the emergency department of Hôpital du Valais in Sion, Switzerland, with a Glasgow Coma Scale (GCS) score of 13-15 and clinical indication for a CT scan were included in the study. Blood samples for S100B measurement were collected from each patient and frozen in 3-hour post-injury intervals. CT scans were performed for all patients. Later, serum S100B levels were compared to CT scan findings in order to evaluate the biomarker's performance. Results: Of the 130 included cases of mTBI, 87 (70%) were related to ski practice. At the internationally established threshold of 0.1 µg/L, the receiver operating characteristic curve of S100B serum levels for prediction of abnormal CT scans showed 97% sensitivity, 11% specificity, and a 92% negative predictive value. Median S100B concentrations did not differ according to sex, age, or GCS score. Additionally, there was no significant difference between skiers and non-skiers. However, a statistically significant difference was found when comparing the median S100B concentrations of patients who suffered fractures or had polytrauma and those who did not suffer fractures. Kahouadji et al. S100B and Ski-Related mTBI Patient Management Conclusion: The performance of S100B in post-mTBI brain lesion screenings seems to be affected by peripheral lesions and/or ski practice. The lack of neurospecificity of the biomarker in this context does not allow unnecessary CT scans to be reduced by one-third as expected.

Previous studies suggested that ongoing treatment with renin–angiotensin–aldosterone system (RAAS) inhibitor drugs may alter the course of SARS‐CoV‐2 infection and promote the development of more severe forms of the disease. The authors conducted a comparative, observational study to retrospectively analyze data collected from 394 patients admitted to ICU due to SARS‐CoV‐2 pneumonia. The primary aim of the study was to establish an association between the use of RAAS inhibitor drugs and mortality in the ICU. The secondary aims of the study were to establish an association between the use of RAAS inhibitor drugs and clinical severity at ICU admission, the need for tracheal intubation, total days of mechanical ventilation, and the ICU length of stay. The authors found no statistically significant difference in ICU mortality between patients on RAAS inhibitor drugs at admission and those who were not (31.3% versus 26.2% mortality, p ‐value 0.3). However, the group of patients taking RAAS inhibitor drugs appeared to be more critical at ICU admission, and this difference became statistically significant in the subgroup of non‐hypertensive patients. ICU mortality in the subgroup of non‐hypertensive patients treated with RAAS inhibitor drugs also tended to be higher. Overexpression of the angiotensin‐converting enzyme 2 (ACE2) in human cells, induced by RAAS inhibitor drugs, promotes viral entry‐replication of SARS‐CoV‐2 and alters the basal balance of the RAAS, which may explain the findings observed in the present study. These phenomena may be amplified in non‐hypertensive patients treated with RAAS inhibitor therapy.