Pseudotumor inflamatorio: diagnóstico diferencial de los tumores del IV ventrículo

Abstract

An inflammatory pseudotumour is a condition of unknown origin and inflammatory nature. It is rarely found in the CNS. We report a case of inflammatory pseudotumour localized to the IV ventricle and review the clinical characteristics of previously reported cases in order to outline the clinical profile of this condition. A 40 year old man was admitted to hospital complaining of a subacute condition involving difficulty in speaking and in moving his right arm and leg. On examination he had ocular deviation on initial gaze, a complete right Horner's syndrome, right supranuclear facial palsy, dyssynergy-asymmetry on the right finger-nose test and a dissociated sensitivity disorder of the left arm. On MR of the brain there was a space occupying lesion, nodular in form and fixed to the roof of the fourth ventricle. The histopathological report on the specimen removed by surgery stated it to be an inflammatory pseudotumour. On a MEDLINE search for reported cases of inflammatory pseudotumour of the CNS, 27 were found since 1967. Four cases, including ours, involved masses growing into the interior of the fourth ventricle. Inflammatory pseudotumour of the CNS is a condition affecting young adults, with a slight male predominance and some association with clinical and analytical data suggesting autoimmune dysfunction. The intraventricular site, particularly within the fourth ventricle, is relatively common (4/28) and is usually associated with clinical features of dysfunction of the posterior fossa and/or intracranial hypertension. We consider that inflammatory pseudotumour should be included in the differential diagnosis of tumours of the fourth ventricle.