FIG 1:-MRI of brain showing T2 AND FLAIR view of temporo-parietal region
So she was diagnosed as case of ADEM and was treated accordingly with
i/v methylprednisolone 20mg/kg body weight for 5 days followed by oral
corticosteroids in tapering dose for 6 weeks.
Discussion
ADEM commonly referred to as post infectious encephalomyelitis affects
the central nervous system and is characterised by demylination of the
brain and spinal cord. (1) A rare autoimmune disorder known to be
affecting 1 in 1,25,000-1,50,000 population most commonly affects the
younger age group (2),presents with symptoms ranging initially from non
specific such as fever, nausea, vomiting, fatigue, lethargy,
irritability, malaise, nausea, weight loss, confusion, stupor and
coma.(9)The specific neurological symptoms comprise of leg/arm weakness,
tingling or numbness, Seizures,altered mental status, vision loss as it
occasionally involves the optic nerve(1,9).The extent of presentations
vary between the affecting individuals depending on the age of onset and
the location of the lesions (9).
In the later stages the patients can also present with ataxia, slurring
of speech and cranial nerve dysfunction.(1,2,9)
Our patient presented with fever, headache and one episode of seizure
with altered mental status, loss of consciousness, reduced GCS , signs
of meningeal irritation bilateral plantar extensor mimicking
meningoencephalitis.She was treated with empirical antibiotics and
antiviral for meningoencephalitis. According to Suvasini sharma et
al(10) headache and vomiting are reported in 38 to 52% of the patients,
seizure in 13 to 47% , meningismus in 5 to 43%. Fever and seizure are
more frequently associated with ADEM as compared to other demyelinating
syndromes.(10) Seizures are common ranging from focal
togeneralised(7).The exact pathophysiology isn’t understood but it is
most commonly considered to be associated with immune response following
infections or vaccination .(1,2,9) There is no specific diagnostic
criteria, a good history, clinical examination and relevant examination
findings helps the establishment of the diagnosis. In two third of
patients abnormal CSF findings are seen i.e. moderate pleocytosis with
raised proteins and absence of oligoclonal bands.(7)
MRI of the brain shows hyperintense lesion on T2 weighted, FLAIR, proton
density and echo planar trace diffusion free sequences.(1)ADEM can also
present as space occupying lesion( SOL) (7) involvement can be present
either as a single lesion or in the form of multiple lesions .(1).
Our patient’s CSF findings were normal but the MRI of brain showed
multiple abnormal T2 hyperintense signal in both parieto-frontal white
matter.Treatment Options include high dose corticosteroids preferably
methylprednisolone and dexamethasone.Intravenous immunoglobulin(IVIG)
can be considered if the patient doesn’t respond to steroids.Clinical
trials also suggest plasmapheresis to be considered as one of the
treatment Options. Rehabilitation therapy should be considered for those
having cognitive or speech impairment, epilepsy , visual and motor
problems (7).
We started high dose IV methylprednisolone for our patient and she
showed dramatic improvement following the treatment which was later
followed by oral steroids.
Clinical progress of ADEM is rapidly progressive with rapid
deterioration within 2 to 5 days.Rarely owing to brain stem involvement,
respiratory failure may occur (10)
Children usually have a good prognosis but severe cases may have
residual abnormalities, one fourth of the cases havea poor
prognosis(8).
On the first follow up our patient had mild generalised weakness
otherwise she was normal.on the 2nd follow up after 2 weeks , she was
completely fine with no any residual
abnormalities.
Conclusion
Though ADEM is a rare autoimmune neurological disorder with a incidence
of 1 in 125,000 -250,000 it still can be treated by early diagnosis and
treatment. The main goal of the authors here is to highlight a case of
ADEM and where eary diagnosis and treatment was beneficial for the
patient. Children are the ones who are affected by ADEM so it is very
much crucial to suspect ADEM for early and diagnosis and treatment.
After covid-19 and its vaccination cases of ADEM are increasing so we
must keep in mind it can be ADEM if there will be presentation like that
of this case.
Conflict of interest-None to disclose
Fundings-The authors didn’t receive any fundings for the paper.
Author contribution- The first author contributed to writing the first
draft of manuscript and literature review and all the other authors
contributed to critically reviewing and revising for the final
publication.
References
1. Anilkumar, A. C., Foris, L. A., & Tadi, P. (2023). Acute
Disseminated Encephalomyelitis . StatPearls Publishing.Available from:
https://www.ncbi.nlm.nih.gov/books/NBK430934/