Acute Disseminated Encephalomyelitis

Original Editor - Hagar Ashraf Abdul-Raziq Top Contributors - Hagar Ashraf Abdul-Raziq and Kim Jackson

Introduction

Acute Disseminated Encephalomyelitis (ADEM), a rare disorder of the central nervous system, is an inflammatory demyelinating disorder with multifocal and aggressive neurological impairment associated with a viral infection or vaccination.

In general, young adults in their twenties and thirties are thought to be affected by this illness.

It frequently has a monophasic course and a good functional recovery. Over the course of several weeks, patients progressively improve, with 50–70% achieving full recovery. However, multiphasic and recurrent forms have also been documented.

Clinical Presentation

Encephalopathy (irritability, confusion, somnolence, lethargy, and stupor) and multifocal deficits in the nervous system are the primary signs of ADEM.

Symptoms are classified to typical and atypical

Typical:

• prodromal symptoms (headache, malaise, irritability, fever, nausea, and vomiting)
• Altered mental status
• Focal neurological symptoms (based on the part of the brain that is affected)
• Meningism

Atypical:

• Progressive onset, recurrent seizures (most common in pediatric cases), persistent headaches, stroke-like episodes, dystonia or parkinsonism, and neuropsychiatric symptoms.

Common exam findings also include ataxia, extremity weakness, urinary retention

Children with ADEM also reported feeling more exhausted, having less energy to exercise, and having impaired motor function.

Causes

ADEM is an autoimmune CNS disorder that affects genetically susceptible people and is brought on by a trigger from the environment.

There are numerous pathogens that have been linked to ADEM, including measles, rubella, varicella zoster, influenza, Epstein–Barr virus, herpes simplex virus (HSV), and beta-hemolytic Streptococcus

Multiple cases of ADEM were reported in 2020 as a result of the global pandemic linked to SARS-CoV-2 infection, which caused severe acute respiratory syndrome.

Diagnostic Procedure

Due to the lack of specific biomarkers and the variability of clinical manifestations, ADEM diagnosis is difficult. The initial step of evaluation is a thorough clinical history and neurologic examination, which frequently reveals multifocal symptoms.

Clinical finding that characterizes ADEM are:

• A first polyfocal, clinical CNS event with a suspected inflammatory demyelinating cause
• encephalopathy that is not attributable to postictal symptoms, fever, or a systemic illness.
• Three months after the onset, there are no new findings on magnetic resonance imaging (MRI) or clinical examination.
• Brain MRI abnormalities occur during the acute phase (three months).

Diagnostic tools includes:

• Neuroimaging
  • MRI brain
  • MRI spine
• CSF studies
• Serum studies
• Adjunctive tests for alternative diagnoses, such as vascular, infectious, neoplastic, or disorders related to metabolism, genetics, or mitochondrial abnormalities.

Inpatient therapists and rehabilitation doctors can evaluate a child receiving immunotherapies for deficiencies in gross motor, fine motor, and speech/swallowing function.

Intervention

It is crucial to maintain breathing, heart, and airway function. For patients who are bedridden, preventive measures against venous thromboembolism are also necessary. In order to shorten the illness's duration and severity, it is imperative that therapies aimed at lowering inflammation and immune activation be initiated. these interventions consist of high-dose corticosteroids (first-line therapy), intravenous immunoglobulin (IVIG), and therapeutic plasma exchange (PLEX)

When appropriate, starting physical, occupational, and speech therapy early can promote a quicker and more thorough recovery. Physical therapy modalities can include ADL training, PROM, NDT, PRET, and biofeedback therapy.

Differential Diagnosis

Classified as demyelinating inflammatory diseases affecting the central nervous system, ADEM and MS can be difficult to distinguish at first clinical presentation.

Systemic symptoms, which are generally uncommon in pediatric MS, such as headache, fever, nausea, vomiting, and altered mental status, are present in the majority of patients with pediatric ADEM.

Case Reports

A 30-year-old woman with loss of vision and tetraplegia. The main goals of the physiotherapy program were bed mobility, stretching exercises for all joints, and passive range of motion. The main goals of occupational therapy were environment and home modifications, as well as training in functional abilities through audio-visuo-tactile stimulation. Her motor, cognitive, and functional recovery was notable following a month-long stay in an inpatient rehabilitation facility. She required only minimal assistance to stand and move around.

The 15-year-old boy in this case report underwent physical therapy that included progressive resistance exercise therapy (PRET), bladder training, neurodevelopmental therapy (NDT), striking, balance training, and ADL training. After four months, he was released in a stable state after making steady progress.