Olfactory impairment in autoimmune encephalitis: another piece of the puzzle.

BACKGROUND: Despite being long neglected, olfaction has recently become a focus of intense research in neuroscience, as smell impairment has been consistently documented in both neurodegenerative and neuroinflammatory diseases. Considering the close anatomo-functional correlations between the limbic system and the central olfactory structures, we investigated olfaction in a population of patients with autoimmune encephalitis (AE). METHODS: Nineteen adult subjects (14 males, median age 64 years) diagnosed with definite (14/19) or possible (5/19) AE and followed for ≥ 6 months were enrolled. The Brief Smell Identification Test (B-SIT), a 12-item, forced-choice, scratch-and-sniff measure, was used to assess the patients' olfactory function in comparison with a group of sex- and age-matched healthy controls (HC). According to the B-SIT score, subjects were classified as anosmic (< 6), hyposmic (6-8) and normal (≥ 9). Electro-clinical, laboratory and neuroimaging findings were reviewed. RESULTS: Smell impairment was revealed in 15/19 patients (9 hyposmic, 6 anosmic), compared with 5/19 HC (p = 0.0029). Age, gender and smoking habits did not affect the participants' performance at B-SIT. Olfactory dysfunction appeared more common among patients with definite AE (p = 0.0374), regardless of autoantibody status. Subjects with higher modified Rankin Scale (mRS) scores at AE onset more likely presented hyposmia/anosmia (p = 0.033), and so did those with bilateral ictal/interictal EEG abnormalities (p = 0.006). CONCLUSIONS: We found olfaction to be impaired in a significantly large proportion of AE cases. Smell deficits appeared more common in subjects with severe AE (as indicated by both definite diagnosis and higher mRS score), and might represent an additional feature of immune-mediated encephalitis.

Effect of the COVID-19 pandemic and the lockdown measures on the local stroke network.

INTRODUCTION: The COVID-19 outbreak highly impacted the acute ischemic stroke care management. The primary end point of the study was to evaluate the impact of the COVID-19 outbreak and the following lockdown measures on our hub-and-spoke network; the secondary end point was to evaluate if the impact of the COVID-19 outbreak was different in hub-and-spoke centers. METHODS: This was a retrospective multicenter observational study conducted at the Stroke Units of Policlinico Gemelli, Ospedale San Filippo Neri, Ospedale di Belcolle, and Ospedale San Camillo de Lellis. We collected clinical reports of all consecutive patients admitted with diagnosis of acute ischemic stroke or transient ischemic attack (TIA) during the phase 1 of the lockdown period (11 March 2020-4 May 2020). As controls, we used all consecutive patients admitted for acute ischemic stroke or TIA in the same period of the previous year. RESULTS: A total of 156 and 142 clinical reports were collected in 2019 and 2020, respectively. During the COVID-19 outbreak, we observed a reduction of number of thrombolysis, a reduction of the length of hospitalization, and an increase of pneumonia. Regarding performance indicators, we observed an increase in onset-to-door time and in door-to-groin time. We did not observe any statistically significant interaction between year (2019 vs 2020) and facility of admission (hub vs spoke) on all variables analyzed. DISCUSSION: Our observational study, involving hub-and-spoke stroke network of a wide regional area, indicates that the COVID-19 outbreak impacted on the acute stroke management. This impact was equally observed in hub as well as in spoke centers.

Neurological Sequelae in Patients with COVID-19: A Histopathological Perspective.

BACKGROUND: Neuroinvasive properties of SARS-CoV-2 have allowed the hypothesis of several pathogenic mechanisms related to acute and chronic neurological sequelae. However, neuropathological correlates have been poorly systematically investigated, being retrieved from reports of single case or limited case series still. METHODS: A PubMed search was carried out to review all publications on autopsy in subjects with "COronaVIrus Disease-19" (COVID-19). Among them, we focused on histological findings of the brain, which were compared with those from the authors' autoptic studies performed in some COVID-19 patients. RESULTS: Only seven studies reported histological evidence of brain pathology in patients deceased for COVID-19, including three with reverse transcription-quantitative polymerase chain reaction evidence of viral infection. All these studies, in line with our experience, showed vascular-related and infection-related secondary inflammatory tissue damage due to an abnormal immune response. It is still unclear, however, whether these findings are the effect of a direct viral pathology or rather reflect a non-specific consequence of cardiovascular and pulmonary disease on the brain. CONCLUSIONS: Notwithstanding the limited evidence available and the heterogeneity of the studies, we provide a preliminary description of the relationship between SARS-CoV-2 and brain sequelae. Systematic autoptic investigations are needed for accurate detection and adequate management of these patients.