Acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis (ADEM), which is classified as a demyelinating disease of the central nervous system (CNS), is a condition that may be regarded as a bridge linking neurology and the infectious diseases. According to the classic definition, ADEM is a monophasic disease that can arise spontaneously; in most cases, however, it is triggered by systemic viral infections or, more rarely, by vaccinations. As the most recent publications on this topic have shown, ADEM can present a relapsing course, being described as "recurrent" if the affected districts are always the same, or "multiphasic" if there is a dissemination in space and time of the lesions, together with a more or less marked association with polyradiculoneuritis. The clinical features and history of the disease create difficulties in differential diagnosis both with encephalomyelitis caused by infectious agents and with noninfectious inflammatory diseases (other demyelinating syndromes, vasculitis, nonvasculitic autoimmune encephalopathies). This paper describes the main features of ADEM, focusing in particular particular on the factors that influence its outcome and can guide the process of differential diagnosis.

Varicella zoster virus meningo-encephalo-myelitis in an immunocompetent patient.

OBJECTIVE: To describe clinical, MRI and cerebrospinal fluid (CSF) features of a varicella zoster virus (VZV) related meningo-encephalo-myelitis (MEM) without rash in an immunocompetent female. PATIENT: An 85 year old immunocompetent woman with mild hyperthermia and acute, severe MEM. INTERVENTION: Serum antibodies and CSF PCR were searched for several viruses. Brain and spinal cord MRI were performed. Immunological profile. TREATMENTS: i.v. acyclovir 30 mg/kg/day; i.v. 6-MP 125 mg/day. RESULTS: Marked CSF lymphomonocytic pleocytosis, blood-brainbarrier damage, and PCR detection of 3.05 X 10 6 copies of VZV DNA. MRI revealed lesions of the meninges, brain and spinal cord. No evidence of immunosuppression. CONCLUSION: We highlight the importance of considering the possibility of VZV related MEM, even in immunocompetent patients. We also provide a MRI description of VZV related multifocal myelitis, not previously available. As supported by other reports, we underline the necessity of a prompt therapeutic intervention in this life-threatening condition.