Laryngotracheal aspiration test reduce the false negative rate in patients with suspected SARS-COV-2 pneumonia despite a negative nasopharyngeal swab.

BACKGROUND: In the emergency department (ED) definitive diagnosis of SARS-COV-2 pneumonia is challenging as nasopharyngeal swab (NPS) can give false negative results. Strategies to reduce false negative rate of NPS have limitations. Serial NPSs (24-48 h from one another) are time-consuming, sputum can not be collected in the majority of patients, and bronchoalveolar lavage (BAL), the most sensitive test, requires specific expertise. Laryngotracheal aspiration (LTA) is easy to perform and showed a similar accuracy to BAL for diagnosis of other pulmonary diseases, however it was not studied to diagnose SARS-COV-2 pneumonia. OBJECTIVE: An observational cross-sectional study was performed to evaluate the negative predictive value of LTA in patients with suspected SARS-COV-2 pneumonia despite a negative NPS. METHODS: In the EDs of two university hospitals, consecutive patients with suspected SARS-COV-2 pneumonia despite a negative NPS underwent LTA performed with a nasotracheal tube connected to a vacuum system. Final diagnosis based on all respiratory specimen tests (NPS, LTA and BAL) and hospital data was established by two reviewers and in case of discordance by a third reviewer. RESULTS: 117 patients were enrolled. LTA was feasible in all patients and no patients experienced adverse events. Fifteen (12.7%) patients were diagnosed with community-acquired SARS-COV-2 pneumonia: 13 LTA positive and only 2 (1.7%) LTA negative. The negative predictive value of NPS and LTA was 87.3% (79.9% - 92.7%) and 98.1% (93.3%99.8%) respectively. CONCLUSIONS: LTA resulted feasible, safe and reduced false negative rate in patients with suspected SARS-COV-2 pneumonia despite a negative NPS.

Particulate Air Pollution, Clock Gene Methylation, and Stroke: Effects on Stroke Severity and Disability.

Circadian rhythm disturbances have been consistently associated with the development of several diseases, particularly cardiovascular diseases (CVDs). A central clock in the brain maintains the daily rhythm in accordance with the external environment. At the molecular level, the clock is maintained by "clock genes", the regulation of which is mainly due to DNA methylation, a molecular mechanism of gene expression regulation, able to react to and be reprogrammed by environmental exposure such as exposure to particulate matter (PM). In 55 patients with a diagnosis of acute ischemic stroke, we showed that PM2.5 exposure experienced before the event influenced clock genes methylation (i.e., circadian locomotor output cycles protein kaput CLOCK, period 2 PER2, cryprochrome 1 CRY1, Neuronal PAS Domain Protein 2 NPAS2), possibly modulating the patient prognosis after the event, as cryptochrome 1 CRY1 and period 1 PER1 methylation levels were associated with the Rankin score. Moreover, if PM2.5 annual average was low, CRY1/CRY2 methylation levels were positively associated with the National Institutes of Health Stroke Scale (NIHSS) score, whereas they were negatively associated if PM2.5 exposure was high. Whether epigenetic changes in clock genes need to be considered as a prognostic marker of stroke or rather a causal agent in stroke development remains to be determined. Further studies are needed to determine the role of clock gene methylation in regulating the response to and recovery after a stroke event.

Cardiac Autonomic Derangement is Associated with Worse Neurological Outcome in the Very Early Phases of Ischemic Stroke.

BACKGROUND: Acute ischemic stroke (AIS) is associated with autonomic dysfunction. We evaluated the prognostic value of heart rate variability (HRV) and the role of stroke localization and reperfusion treatment (RT) on autonomic control. METHODS: Patients with AIS and sinus rhythm were enrolled in the emergency department. Autonomic parameters were recorded at the onset and after a potential RT. Neurological deficit was assessed using the National Institute of Health Stroke Scale (NIHSS) at the onset and residual disability with modified Rankin Scale (mRS) at 3 months. Two analyses were used to assess HRV. Low frequency (LF) and high frequency (HF) are, respectively, markers of sympathetic and respiratory vagal modulation in spectral analysis. Symbolic analysis provides pattern with no variation (0V%) as an index of sympathetic modulation and pattern with two like variations (2LV%) and pattern with two unlike variations (2UV%) as markers of vagal modulation. RESULTS: We enrolled 41 patients. Twenty-seven underwent RT. A prevalent parasympathetic modulation was found in patients with NIHSS ≥14. The group with mRS 3-6 exhibited a higher 2UV% and lower 0V%. Right-sided strokes were associated with a higher respiratory vagal control. RT had no effects on HRV parameters. CONCLUSIONS: In the very early phases of AIS, a decreased 0V% and an increased 2UV% may reflect a loss of sympathetic oscillation, predicting a poorer 3 month-outcome.