Atypical Presentation of Acute Disseminated Encephalomyelitis (ADEM) in a Middle-Aged Adult

Abstract

Patient: Male, 47 Final Diagnosis: Acute disseminated encephalomyelitis (ADEM) Symptoms: Spastic paresis Medication: Methylprednisolone Clinical Procedure: — Specialty: General and Internel Medicine Objective: Rare disease Background: Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease that usually presents in pediatric patients, usually following a viral or bacterial infection. The clinical findings in ADEM include acute neurologic decline that typically presents with encephalopathy, with some cases progressing to multiple sclerosis. An atypical case of ADEM is reported that presented in a middle-aged adult. Case Report: A 46-year-old Caucasian man, who had recently emigrated to the US from Ukraine, presented with gait abnormalities that began four days after he developed abdominal cramps. Magnetic resonance imaging (MRI) of the brain with contrast, fluid-attenuated inversion recovery (FLAIR), and T2-weighting showed contrast-enhancing, patchy, diffuse lesions in both cerebral hemispheres. Cerebrospinal fluid (CSF) was negative for oligoclonal bands. On hospital admission, the patient was treated with intravenous (IV) methylprednisolone, 500 mg twice daily. He responded well and was discharged from hospital after a week, with resolution of his presenting symptoms and signs. Conclusions: This report is of an atypical presentation of ADEM in a middle-aged patient who presented with spastic paresis. Although there are no set guidelines for the diagnosis of ADEM in adults, this diagnosis should be considered in patients with acute onset of demyelinating lesions in cerebral MRI. As this case has shown, first-line treatment is with high-dose steroids, which can be rapidly effective.

Insights from neuroradiology in acute disseminated encephalomyelitis

“…MS lesions tend to appear in both the subcortical white matter and the periventricular margin [9] . On the other hand, MRI scans of ADEM show patchy, increased signal intensity on conventional T2-weighted imaging and FLAIR MRI [6] . ADEM lesions are predominantly located in the subcortical white matter, with relatively spared periventricular white matter [9] .…”

“…When comparing ADEM with MS on MRI, MS lesions typically exhibit better demarcation compared to the less distinct lesions found in ADEM. Additionally, T1-weighted MRI scans with findings such as the black hole sign are more indicative of MS [6] . MS lesions tend to appear in both the subcortical white matter and the periventricular margin [9] .…”

“…In a case described by Liardino et al. [ 6 ], a 47-year-old male presented to the emergency department with bilateral lower extremity weakness and a spastic gait. He had experienced diffuse abdominal cramping pain four days prior.…”

“…Typically, ADEM follows a monophasic clinical course, and instances of relapsing ADEM are rare [5] . Due to a limited understanding of the disease, ADEM is sometimes mistaken for multiple sclerosis (MS) or other demyelinating diseases [2 , 6] .…”

“…ADEM cases in adults are infrequent, and the clinical course within this age group remains mostly unknown [7] . Although 50%-75% of adult cases recover, around 20% progress to multiple sclerosis [6] . In this report, we present the case of an 18-year-old who developed ADEM and experienced recovery after receiving a trial of IV methylprednisolone.…”