Moyamoya syndrome after bacterial meningitis

Numerous small collateral blood vessels were found within the base of the brain and distal middle cerebral arteries (Figure B). Information about three previously reported MMS cases Case Number Pathogen Gender/Age (years) Progression of clinical manifestation Progression of vasculopathy Follow‐up time/Outcomes Case 1 H. influenzae F/51 6 weeks: headache, episode of left‐side numbness; 2 months: severe headache; 7 months: headache improved 2 months: normal in angiography; 7 months: stenosis in bilateral; supraclinoid segment of the ICA, bilateral Ml, left intracranial VA, right P1; 9 months: primary stenosis progressing, proliferation of lenticulostriate collateral vessels 3 years/ no headache, improvement in the degree of stenosis and persistence of collateral vessels Case 2 S. pneumoniae M/55 3 months: headache, hemiplegia 3 months: stenosis‐occlusion in bilateral supraclinoid segment of the ICA, bilateral A1, M1, VA‐BA system, appearance of collateral vessels lenticulostriate collaterals 0.5 years / hemiplegic symptom improved, no relapses had occurred, motor improvement Case 3 S. pneumoniae F/20 9 days: hemiplegia 48 days: headache, and CT shows evolution of the previously noted infarcts 118 days: language problem 139 days: cortical Blindness and MRI shows new occipital infarction 260 days: a large left basal ganglion hemorrhage and died 12 days: moderate stenosis of distal bilateral VA and BA, mild stenosis of left M1, left A1 150 days: severe stenosis in the BA and VA, progressing of left M1, new stenosis of the A1, appearance of lenticulostriate collaterals. 237 days: proliferation of posterior penetrating vessels, further proliferation of lenticulostriate collaterals 0.7 years / a large left basal ganglion hemorrhage and died The base pathophysiology of MMS is stenosis/occlusion in the terminal portions of the internal carotid artery and its main branches, where the stenosis or occlusion of arteries leads to reduced blood flow in the anterior circulation of the brain and the subsequent development of compensatory collateral vessels. [...]the symptoms of MMS can be classified into two categories: brain ischemia (i.e., stroke, transient ischemic attacks [TIAs], and seizures) and compensatory collateral vessels (i.e., hemorrhage). According to the literature, other possible pathogeneses for post‐infective vasculopathy include reactive vasospasm and residual organic stenosis due to infection, autoimmune processes, and host susceptibility to autoimmune d