Delayed cerebral thrombosis complicating bacterial meningitis.

Background: Delayed cerebral thrombosis has been described as a potential cause of cerebrovascular complications in patients with bacterial meningitis. We report a case of delayed cerebral thrombosis in a 63-year-old woman admitted for pneumococcal meningitis. Initially, there was a good clinical evolution under treatment with steroids and antibiotics. On day 8 after admission, she was found with a decreased level of consciousness. Her neurological condition gradually worsened. Repeated brain imaging showed extensive ischemic lesions. Despite treatment with high-dose corticosteroids, the patient died.
Methods: A literature search was conducted. Data on patient characteristics, diagnosis, treatment and outcome were collected.
Results: To date, 28 cases with delayed cerebral thrombosis following bacterial meningitis have been reported. Streptococcus pneumoniae was the pathogen in 89% of cases. Clinical deterioration occurred in all patients, with a duration varying from 5 to 40 days between admission and deterioration. Most common symptom was altered consciousness (83%), followed by hemiparesis (52%). Brain imaging typically shows new infarctions (96%). Fifty-six percent of patients were treated with corticosteroids after deterioration. Outcome was poor with mortality rate of 46%.
Conclusion: Delayed cerebral thrombosis presents as a clinical deterioration, typically a sudden decline in consciousness, more than 5 days after meningitis onset. Brain imaging shows new widespread ischemic lesions. Diagnosis should be made carefully, based on clinical findings and brain imaging, after excluding endocarditis. The underlying etiology remains unknown. When delayed cerebral thrombosis is suspected, high-dose corticosteroids should be started empirically. The prognosis remains poor with high mortality rates.