Microbleed patterns in critical illness and COVID-19

Area of Science:

• Neurology
• Critical Care Medicine
• Infectious Diseases

Background:

• Cerebral microbleeds are increasingly noted in critically ill patients with respiratory failure requiring mechanical ventilation or ECMO.
• These microbleeds typically affect juxtacortical white matter and the corpus callosum.
• A similar pattern has been observed in COVID-19 patients with respiratory failure.

Observation:

• This study identified two cases of cerebral microbleeds in critically ill COVID-19 patients with respiratory failure.
• One patient presented with typical critical illness-associated microbleed patterns.
• A second patient exhibited a novel pattern of widespread cortico-juxtacortical microbleeds, primarily in the anterior vascular territory.

Findings:

• The novel pattern involved relative sparing of deep gray matter, corpus callosum, and infratentorial structures.
• Potential etiologies include hypoxia, hemorrhagic diathesis, brain endothelial erythrophagocytosis, and cytokinopathies.
• The direct association between this new microbleed pattern and COVID-19 requires further investigation.

Implications:

• These findings highlight the diverse neurological manifestations of severe COVID-19.
• Further research is needed to understand the specific mechanisms and clinical significance of these microbleeds.
• Systematic investigation of microbleed patterns in COVID-19 patients with neurological impairment is crucial.