Background A wide range of neurological manifestations has been described in COVID-19. Methods In this nationwide retrospective observational study, patients in Tunisia diagnosed with COVID-19 between the 2nd of March and the 16th of May 2020 were contacted by telephone. We collected demographic and clinical data and specified characteristics and evolution of main neurological symptoms. Results Of 1034 confirmed COVID-19 patients, 646 were included (mean age 42.17 years old) and 466 (72.1%) had neurological symptoms. Neurological symptoms were isolated 22.7% ( n = 106). Headache was the most frequent neurological symptom ( n = 279, 41.1%): mainly frontotemporal ( n = 143, 51.1%) and mild or moderate ( n = 165, 59.1%). When associated with fever ( n = 143, 51.3%), headache was more likely to be severe and present at onset. Recovery was reported in 83.2%. Smell and taste impairment were found in 37.9% ( n = 245) and 36.8% ( n = 238) respectively. Among them, 65.3% (156/239) were anosmic and 63.2% (146/231) were ageusic. A complete improvement was found in 72.1% (174/240) of smell impairment and in 76.8% (179/233) of taste impairment. Myalgia ( n = 241, 37.3%) and sleep disturbances ( n = 241, 37.3%) were also frequent. Imported cases had more neurological symptoms ( p = 0.001). In 14.5%, neurological symptoms preceded the respiratory signs (RS). RS were associated with more frequent ( p = 0.006) and numerous ( p < 0.001) neurological symptoms. Conclusions Neurological symptoms in COVID-19 are frequent, can be isolated and present at onset. A total recovery is the most recorded outcome. RS are predictive of neurological symptoms. Studies in to virus and host genetics should be considered to understand the different phenotypes.

Mesenchymal cells are an essential cell type because of their role in tissue support, their multilineage differentiation capacities and their potential clinical applications. They play a crucial role during lung development by interacting with airway epithelium, and also during lung regeneration and remodeling after injury. However, much less is known about their function in lung disease. In this review, we discuss the origins of mesenchymal cells during lung development, their crosstalk with the epithelium, and their role in lung diseases, particularly in chronic obstructive pulmonary disease.