Tình trạng này được gây ra bởi amoebae sống của các loài Naegleria fowleri. Họ sống trong đất ẩm và hầu hết các trường hợp đã được báo cáo ở trẻ em đã được bơi lội hoặc chơi trong nước trì trệ. | NEUROLOGICAL EMERGENCIES Primary amoebic encephalitis This condition is caused by free living amoebae of the species Naegleria fowleri. They live in moist soil and most cases have been reported in children who have been swimming or playing in stagnant water. Amoebae enter the nasal cavity cross the nasal epithelium and ascend to the brain along olfactory nerves and blood vessels to frontal and basal meninges and spread causing a florid necrotising inflammation. Clinically the presentation is of a sudden onset of severe meningitis indistinguishable from bacterial The clue to diagnosis is the history of exposure to warm stagnant water. CSF examination reveals pleocytosis in which polymorphs predominate raised protein and reduced glucose. No organisms are seen on the gram stain and special examination of fresh warm specimens of CSF will show motile trophozoites. Most patients die rapidly despite treatment but survival following treatment with amphotericin B has been described 141 and this should be given in the highest tolerated dose parenterally reinforced by intracisternal injection and by rifampicin and tetracycline which have some activity against Acanthamoeba spp. tend to cause a subacute granulomatous meningoencephalitis. Brain abscess and subdural empyema Intracranial abscesses remain a diagnostic and therapeutic challenge despite the considerable advances that have taken place in recent decades in imaging techniques neurosurgical practice bacteriological isolation of causal organisms and the introduction of more potent 144 They frequently present as emergencies and as with all forms of cerebral infection delay in diagnosis and implementation of treatment and inappropriate investigation adversely affect the The incidence of brain abscess is 1-3 per 100 000 person-years and this has fallen in recent years. Brain abscesses account for approximately 1 in 10 000 admissions in the United Both brain
