Brainstem neuropathology in two cases of COVID-19: SARS-CoV-2 trafficking between brain and lung.
INTRODUCTION
SARS-CoV-2 might spread through the nervous system, reaching respiratory centers in the brainstem. Because we recently reported neurophysiological brainstem reflex abnormalities in COVID-19 patients, we here neuropathologically assessed structural brainstem damage in two COVID-19 patients.


MATERIALS AND METHODS
We assessed neuropathological features in two patients who died of COVID-19 and in two COVID-19 negative patients as controls. Neuronal damage and corpora amylacea (CA) numbers /mm2 were histopathologically assessed. Other features studied were the immunohistochemical expression of the SARS-CoV-2 nucleoprotein (NP) and the Iba-1 antigen for glial activation.


RESULTS
Autopsies showed normal gross brainstem anatomy. Histopathological examination demonstrated increased neuronal and CA damage in Covid-19 patients' medulla oblongata. Immunohistochemistry disclosed SARS-CoV-2 NP in brainstem neurons and glial cells, and in cranial nerves. Glial elements also exhibited a widespread increase in Iba-1 expression. Sars-Co-V2 was immunohistochemically detected in the vagus nerve fibers.


DISCUSSION
Neuropathologic evidence showing SARS-CoV-2 in the brainstem and medullary damage in the area of respiratory centers strongly suggests that the pathophysiology of COVID-19-related respiratory failure includes a neurogenic component. Sars-Co-V2 detection in the vagus nerve, argues for viral trafficking between brainstem and lung.
['Bulfamante|Gaetano|G|', 'Bocci|Tommaso|T|', 'Falleni|Monica|M|', 'Campiglio|Laura|L|', 'Coppola|Silvia|S|', 'Tosi|Delfina|D|', 'Chiumello|Davide|D|', 'Priori|Alberto|A|']
D001933:Brain Stem D000086382:COVID-19 D006801:Humans D008168:Lung D009422:Nervous System Diseases D000086402:SARS-CoV-2
Brainstem Neuropathology COVID-19 SARS-CoV-2 Medulla oblongata Neurological COVID-19