[P2-1~135] Poster Presentation 2

[P2-20] An atypical case of acute disseminated encephalomyelitis misdiagnosed as intracranial infection

^○Qianyun CAI^{1, 2} (1.Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China, 2.Key Laboratory of Birth Defects and Obstetric & Gynecologic and Pediatric Diseases of Ministry of Education, Sichuan University, Chengd, Sichuan, China)

We aimed to describe an atypical case of acute disseminated encephalomyelitis (ADEM) misdiagnosed as intracranial infection. A ten-year-old boy presented with irritability, malaise, dysuria, and blurred vision but without fever, convulsion or disturbance of consciousness. Lumbar puncture showed a mild pleocytosis (100 cell/mm3) and a mild increase in protein (87 mg/dl). MRI documented multiple lesions in cortex, white matter, corpus callosum, brain stem, cerebellum and cervical spinal cord on T2/FLAIR sequences. The lesion in the rostrum of corpus callosum was prominent and had mass effect. The patient was successively diagnosed as viral or bacterial encephalitis, and cryptococcal meningitis. However, after the treatment of acyclovir, meropenem, and amphotericin B, his symptoms worsened and he developed high fever, cerebral hernia and central respiratory failure. After consultation of pediatric neurologist, ADEM was considered although the involvement of corpus callosum was atypical. Twelve days after admission, the patient received pulse methylprednisolone and IVIg treatment. High fever and intracranial hypertension gradually relieved but autonomous respiration was not restored. Following second pulse therapy of intravenous methylprednisolone, the patient was weaned from mechanical ventilation. When discharged, he could not walk due to reduced muscle strength of lower limbs. At follow-up after 3 months, the patient was fully ambulatory and MRI showed resolution of brain and spinal cord lesions. To avoid further misdiagnosis, we suggest physicians of emergency department and intensive care unit as well as neurosurgeons should take ADEM into consideration when handling patients with encephalopathy and be familiar with its typical and atypical MRI manifestations.
Key words: acute disseminated encephalomyelitis (ADEM); misdiagnosis; intracranial infection; corpus callosum; MRI