RELAPSING ACUTE DISSEMINATED ENCEPHALOMYELITIS (ADEM)

Karuna Thapar; Gaurav Dhawan

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Karuna Thapar, Gaurav Dhawan.

Department of Pediatrics, Government Medical College, Amritsar.

ADDRESS FOR CORRESPONDENCE
Dr Karuna Thapar, Department of Pediatrics, Government Medical College, Amritsar, India.
Email: kthapar2000@yahoo.com

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Introduction

ADEM is immunologically mediated inflammatory demyelinating disease of CNS. Highest prevalence is seen in prepubertal boys. Clinical manifestations include abrupt development of irritability and neurological signs in children recovering from a viral prodrome. Changes in long tract signs and mental status are commonly observed. We report a case of ADEM with relapse treated effectively with corticosteroid therapy.

Case Report

A 7 years old male child presented with intermittent fever for 25 days, headache for 15 days, irritability, excessive crying, vomiting, and pain abdomen for 5 days. On examination vitals were normal, neck rigidity was present, pupils were bilaterally reacting, tone was normal and reflexes were present. Hemogram, renal functions, liver functions, Electrocardiogram and Chest X-ray were normal. CSF analyses including viral cultures were normal. MRI revealed few small hyper intense lesions in the sub cortical white matter of cerebral hemispheres, left caudate nucleus and rostrum of corpus callosum on right side suggestive of acute disseminated encephalomyelitis. He was treated with intravenous methyl prednisolone for 3 days with which he showed slight improvement and was discharged on oral steroids. The child was readmitted within three months with complaints of decreased vision for 15 days, headache for 10 days, difficulty in micturition for 4 days and irrelevant talks for 1 day. MRI brain revealed that the previous lesions had increased in number and size with involvement of the basal ganglia and the brainstem. The child was given intravenous methyl prednisolone (30mg/kg/day) for three days and then started on oral methyl prednisolone (1mg/kg/day) for two weeks. The child showed dramatic improvement to this therapy and led to resolution of all his neurological deficits. Follow up for 12 months revealed no neurological deterioration.

Discussion

ADEM is an uncommon disease. In most patients it follows a viral illness but has been reported after bacterial infection, immunizations, and drug and serum administration (1,2,3).

The clinical syndrome is variable but can range from focal neurological deficits to coma and death. Typically, ADEM is characterized by an abrupt onset of fever, obtundation, seizures, and focal neurological signs (2). Obtundation may progress to coma and up to 20% of patients die.

The diagnosis is often confirmed by MRI, which shows multifocal white matter lesions corresponding to the abnormal neurological findings (4,5,6,7). Diagnosis in this case was made on the basis of clinical picture and MRI features.

Although ADEM is a monophasic disease, relapses have been described mainly as case reports (8-13). To qualify as definite relapse, the new clinical episode required at least an interval of 1 month from the initial symptom (14), in addition to different symptoms and radiologic evidence of new lesions at a different site (11,14). The concept of definite relapse was considered to differentiate biphasic ADEM (10-12,15,16) from patients with steroid dependence that shows reactivation of the same lesions (13,16,17). The authors think that the presented case qualifies for a relapse as new clinical episode occurred at an interval of more than 1 month, with some different symptoms, and radiologic evidence of new lesions at new site.

Differential diagnosis of Multiple Sclerosis (MS) was also kept by the authors but male predominance, relapse timing of less than 6 months, occurring shortly after cessation of corticosteroids, only one relapse observed, and MRI findings of hyperintense lesions, grey matter involvement pointed more towards biphasic ADEM than MS (18).

There is no standard treatment for ADEM though corticosteroid is the most frequently reported therapy, improving recovery in most patients (8,19). Clinical response is usually evident within hours of initiation of treatment, particularly after pulsed IV corticosteroids (20). Many patients have shown rapid improvement with prednisone. The rationale for corticosteroid use is their ability to reduce inflammation, decrease edema, and seal the blood-brain barrier, which should decrease the further influx of active immune cells and humoral factors, contributing to demyelination. The main therapeutic options for ADEM are corticosteroids, plasma exchange, and intravenous immunoglobulin. Plasma exchange and intravenous immunoglobulins were not used in our patient because the patient showed dramatic improvement with corticosteroids.

We think our patient represents a rare case of relapsing (biphasic) ADEM treated effectively with corticosteroids.

Compliance with Ethical Standards

Funding None

Conflict of Interest None

References

Chang CM, Ng HK, Chan YW, et al. Post infectious myelitis, encephalitis and encephalomyelitis. Clin Exp Neurol 1992;29:250-262. [PubMed]
Johnson RT, Griffin DE , Gendelman HE. Post infectious encephalomyelitis. Semin Neurol 1985;5:180-190. [CrossRef]
Nasralla CAW, Pay N, Goodpasture HC, et al. Post infectious encephalopathy in a child following Campylobacter jejuni enteritis. AJNR Am J Neuroradiology 1993;14:444-448. [PubMed]
Atlas SW, Grossman RI , Goldberg HI, et al. MR diagnosis of acute disseminated encephalomyelitis. J Compute Assisted Tomogr 1986;10:798-801. [CrossRef]
Dunn V, Bale JF Jr, Zimmerman RA, et al. MRI in children with post infectious disseminated encephalomyelitis. Magn Reson Imaging 1986;4:25-32. [CrossRef]
Epperson LW, Whitaker JN, Kapila A. Cranial MRI in acute disseminated encephalomyelitis. Neurology 1988;38:332-333. [CrossRef] [PubMed]
Kesselring J, Miller DH, Robb SA, et al. Acute disseminated encephalomyelitis. MRI findings and distinction from multiple sclerosis. Brain 1990;113:291-302. [CrossRef] [PubMed]
Rust RS. Multiple sclerosis, acute disseminated encephalomyelitis and related conditions. Semin Pediatr Neurol. 2000; 7: 66-90. [CrossRef] [PubMed]
Tenembaum S, Galicchio S, Granana N, Ferrea M, Chamoles N, Fejerman N. Multiphasic disseminated encephalomyelitis and multiple sclerosis in children: diagnostic clues. J Neurol Sci. 1997; 150 (suppl): S230. Abstract. [CrossRef]
Suwa K, Yamagata T, Momoi MT , et al. Acute relapsing encephalopathy mimicking acute necrotizing encephalopathy in a 4-year-old boy. Brain Dev. 1999; 21: 554-558. [CrossRef]
Shoji H, Kusuhara T, Honda Y, et al. Relapsing acute disseminated encephalomyelitis associated with chronic Epstein-Barr virus infection: MRI findings. Neuroradiology. 1992; 34: 340-342. [CrossRef] [PubMed]
Khan S, Yaqub BA, Poser CM, Al Deeb SM, Bohlega S. Multiphasic disseminated encephalomyelitis presenting as alternating hemiplegia. J Neurol Neurosurg Psychiatry. 1995; 58: 467-470. [CrossRef] [PubMed] [PMC free article]
Tsai ML, Hung KL. Multiphasic disseminated encephalomyelitis mimicking multiple sclerosis. Brain Dev. 1996; 18: 412-414. [CrossRef]
Revel-Vilk S, Hurvitz H, Klar A, Virozov Y, Korn-Lubetzki I. Recurrent acute disseminated encephalomyelitis associated with acute cytomegalovirus and Epstein-Barr virus infection. J Child Neurol. 2000; 15: 421-424. [CrossRef] [PubMed]
Poser CM. The epidemiology of multiple sclerosis: a general overview (review). Ann Neurol. 1994; 36 (suppl 2): S180-193. [CrossRef] [PubMed]
Hahn JS, Siegler DJ, Enzmann D. Intravenous gammaglobulin therapy in recurrent acute disseminated encephalomyelitis. Neurology. 1996; 46: 1173-1174. [CrossRef] [PubMed]
Apak RA, Anlar B, Saatci I. A case of relapsing acute disseminated encephalomyelitis with high dose corticosteroid treatment. Brain Dev. 1999; 21: 279-282. [CrossRef]
L Bennetto, N Scolding. Inflammatory/post-infectious encephalomyelitis. J. Neurol. Neurosurg. Psychiatry 2004; 75; 22-28. [CrossRef] [PMC free article]
Pasternak JF, De Vivo DC, Prensky AL. Steroid-responsive encephalomyelitis in childhood. Neurology. 1980; 30: 481-486. [CrossRef] [PubMed]
Straub J, Chofflon M, Delavelle J. Early high-dose intravenous methylprednisolone in acute disseminated encephalomyelitis: a successful recovery. Neurology. 1997; 49: 1145-1147. [CrossRef] [PubMed]