Postinfectious inflammatory disorders: subgroups based on prospective follow-up

Area of Science:

• Neurology
• Immunology
• Infectious Diseases

Background:

• Acute disseminated encephalomyelitis (ADEM) is typically a monophasic inflammatory disease of the central nervous system (CNS).
• However, relapsing and site-restricted variants, sometimes involving the peripheral nervous system (PNS), are observed without a clear classification.
• This study addresses the lack of systematic classification for ADEM variants.

Purpose of the Study:

• To characterize a cohort of postinfectious ADEM patients.
• To propose a classification system for ADEM based on clinical and instrumental findings.
• To identify prognostic factors and patient subgroups with distinct outcomes.

Main Methods:

• A 5-year retrospective study of inpatients diagnosed with postinfectious CNS syndrome.
• Patients were classified based on lesion distribution and clinical presentation.
• Outcomes were assessed over a follow-up period of 24 months to 7 years.

Main Results:

• Of 75 enrolled patients, 60 met ADEM criteria. Variants included encephalitis, myelitis, encephalomyelitis, encephalomyeloradiculoneuritis, and myeloradiculoneuritis.
• Fifty percent of patients had a favorable outcome; 25% experienced a relapsing course.
• Poor outcomes were associated with older age, female gender, elevated CSF proteins, and spinal cord/PNS involvement.

Conclusions:

• A significant prevalence of atypical ADEM variants with CNS and PNS involvement was identified.
• Prognosis and response to steroid treatment were generally favorable, with exceptions in specific subgroups.
• Intravenous immunoglobulin (IVIG) demonstrated a beneficial effect in patients with PNS involvement who did not respond to steroids.