From the Guidelines
Meningitis can cause cortical vessel infarctions (strokes) due to inflammation of blood vessels (vasculitis) that supply the cerebral cortex, resulting in thrombosis, narrowing, or occlusion of these vessels. This vascular complication occurs when the infectious or inflammatory process spreads from the meninges to adjacent blood vessels, as seen in patients with bacterial meningitis and meningococcal sepsis 1. The inflammation can lead to a defective endothelial protein C activation pathway, deficiency in protein C, protein S, and antithrombin III, increasing the risk of thrombosis and subsequent stroke 1.
Key factors that contribute to the development of cortical vessel infarctions in meningitis include:
- Inflammation of blood vessels (vasculitis)
- Thrombosis, narrowing, or occlusion of cortical vessels
- Defective endothelial protein C activation pathway
- Deficiency in protein C, protein S, and antithrombin III
The management of meningitis should prioritize control of raised intracranial pressure, normalization of blood pressure, and maintenance of normocarbia and normoglycaemia to prevent mortality and reduce the risk of vascular complications 1. Prompt treatment of the underlying meningitis with appropriate antibiotics and anti-inflammatory measures is essential to reduce the risk of vascular complications. In some cases, anticoagulation might be considered, though this remains controversial due to the risk of hemorrhagic transformation in inflamed vessels.
From the Research
Cerebrovascular Complications of Meningitis
Meningitis can cause cortical vessel infarctions (strokes) due to various mechanisms, including:
- Vasculitis, vasospasm, endocarditis, or intraarterial thrombosis 2
- Inflammatory response produced to eradicate infectious pathogens, leading to damage to the blood-brain barrier and triggering leukocytes to react to the infection 3
- Bacterial virulence factors and pathogen-associated molecular patterns causing direct damage to the blood-brain barrier and triggering an inflammatory response 3
- Cerebral vasculopathy and hypercoagulation of the cerebral blood vessels, leading to cerebral ischemia 3, 4
Types of Cerebrovascular Complications
The types of cerebrovascular complications that can occur in meningitis include:
- Arterial ischemic stroke 2, 4
- Cerebral sinovenous thrombosis 4
- Lacunar infarcts 5
- Vasculitis, vessel wall irregularities, focal dilatations, and occlusions of distal branches of the middle cerebral artery 6
- Thrombosis of the sagittal superior sinus and cortical veins 6
Risk Factors and Outcomes
The risk factors for cerebrovascular complications in meningitis include:
- Increased cerebral blood flow velocity (CBFv) on transcranial Doppler (TCD) 2
- Presence of fever, neck stiffness, positive blood culture, and hydrocephalus on central nervous system imaging 5
- Longer duration of illness, low sensorium at the time of presentation, low Glasgow Coma Scale score, presence of meningeal inflammation, cryptococcomas, and basal exudates in imaging 5 The outcomes of patients with cerebrovascular complications in meningitis are generally unfavorable, with increased mortality and morbidity 2, 5, 6