[Primary acute disseminated encephalomyelitis in the adult. Study of 6 year follow-up of 2 patients].

INTRODUCTION

The relationship between acute disseminated encephalomyelitis (ADEM), a monophasic disease, and multiple sclerosis (MS), a potentially progressive disease with periods of recurrence or remission, remains debatable. In a large number of patients, the diagnosis initially retained is that of ADEM, whilst the progression is subsequently towards a defined MS. This has incited some authors to consider that there is a continuum between these two diseases and to underline the frailty of the criteria retained for the diagnosis of ADEM. Further interest has presently been paid to this subject and the question of whether a basic treatment of MS should be started after the first episode has been raised, although such a treatment is obviously not justified if the diagnosis retained is an ADEM.

OBJECTIVES

Two cases observed in adults, followed-up for 6 years, contribute to the validation of a number of clinical, biological and radiological arguments which are all in favor of the diagnosis of ADEM versus that of an initial episode of MS.

CLINICAL ARGUMENTS

These are the absence of any neurological past history, the existence of a multi-focal neurological symptomatology right from the start and, particularly in children, the presence of a meningeal syndrome.

BIOLOGICAL ARGUMENTS

Presence in the cephalo-spinal liquid, of an increase in cells and cervicospinal proteins to levels not usually found in MS.

RADIOLOGICAL ARGUMENTS

MRI reveals multi-focal, extensive and bilateral lesions, beneath the cortex rather than peri-ventricular, which may extensively involve the thalamus and the bone marrow; these lesions are of the same age and often regress.