Cerebral amyloid angiopathy (CAA) can occasionally present with encephalopathy, unsteadiness and seizures, as a result of an inflammatory response to the deposition of beta–amyloid within the cerebral blood vessels and leptomeninges. In this case report, we describe a patient who has responded very favourably to immunosuppression. A previously fully independent 67 year old lady presented with a short history of confusion, worsening unsteadiness and self neglect. Neurologically, she was disorientated, dyspraxic with limb weakness and ataxia. MRI showed extensive bilateral white matter change and oedema throughout both hemispheres with numerous grey–white interface microhaemorrhages. These radiological findings were suggestive of an unusual form of cerebral amyloid angiopathy and related leukoencephalopathy. The patient received pulsed intravenous methylprednisolone, followed by regular oral prednisolone. Three weeks later, she began a slow but steady clinical improvement. She relapsed when the prednisolone was tapered off, but currently, she is well maintained on prednisolone and azathioprine, and regained her independence. Although CAA related inflammation is rare, it should be thought of in the differential for extensive leukoencephalopathy and a trial of steroids should be considered early to promote recovery.