PT - JOURNAL ARTICLE AU - Abdel-Aziz, K AU - Benson, R AU - Manohar, R AU - White, R P AU - Barborie, A TI - POC03 Vanishing gliomatosis or two separate pathologies? AID - 10.1136/jnnp.2010.226340.73 DP - 2010 Nov 01 TA - Journal of Neurology, Neurosurgery & Psychiatry PG - e35--e35 VI - 81 IP - 11 4099 - http://jnnp.bmj.com/content/81/11/e35.3.short 4100 - http://jnnp.bmj.com/content/81/11/e35.3.full SO - J Neurol Neurosurg Psychiatry2010 Nov 01; 81 AB - A 51-year-old presented with subacute headache, right facial weakness and numbness. MRIB showed widespread enhancing hemispheric lesions with a focal lesion of the right CN VII nucleus. CSF protein 0.84 g/l; CSF lymphs 10×106/l. A diagnosis of ADEM was made and symptoms resolved soon after steroids. Five months later, he developed a progressively ataxic gait, leg weakness and dysarthria. Second CSF showed 12×106/l lymphs and protein of 0.95 g/l. CSF cytology showed nonspecific, active, chronic inflammation. MRIB revealed minimally enhancing lesions within the internal capsules, lentiform nuclei extending into the cerebral peduncles. Notably, the CN VII nuclear lesion completely disappeared. MRS suggested an infiltrative process and a diagnosis of grade 2 astrocytoma was made following brain biopsy. It has been proposed that dexamethasone modifies disruptions to the BBB and previous authors report resolution of radiological enhancement in glioma following steroids. We found two cases of high grade gliomas vanishing after dexamethasone, only to recur at the same site within 3–20 weeks. Our patient showed progression of the hemispheric lesions but the focal CN VII nuclear lesion vanished on the interval scan performed 11 months after steroids. Our case may represent disappearing glioma or dual pathology. Radiological resolution of lymphoma after steroids is recognised but is not usually associated with glioma. Clinicians may need to be aware of this when considering timing of brain biopsies.