|Year : 2022 | Volume
| Issue : 1 | Page : 335
Infantile-onset myasthenia: Is it always congenital?
Vinit Banga1, Bhanudeep Singanamalla2, Lokesh Saini3
1 Department of Neurology and Neurovascular Intervention, Medanta, The Medcity, Sriganganagar, Rajasthan, India
2 Pediatric Neurology Unit, Department of Pediatrics, KIMS Cuddles, Kondapur, Hyderabad, India
3 Pediatric Neurology Unit, Department of Pediatrics, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
|Date of Web Publication||07-Jan-2022|
Dr. Lokesh Saini
Pediatric Neurology Unit, Department of Pediatrics, All India Institute of Medical Sciences, Jodhpur, Rajasthan
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Banga V, Singanamalla B, Saini L. Infantile-onset myasthenia: Is it always congenital?. Indian J Ophthalmol Case Rep 2022;2:335
A 1-year-old infant presented with complaints of drooping of the left eyelid initially for 2 days, followed by the right eyelid for past 10 days. There was no history of squint, fatiguability, cataract, and similar history in the mother. Examination revealed bilateral ptosis [Figure 1]a, normal pupillary reactions, normal deep tendon reflexes, without motor weakness and meningeal signs. In view of asymmetric onset of ptosis, an initial possibility of oculomotor paresis or myasthenia (congenital vs acquired) was kept. Neuroimaging (magnetic resonance imaging brain) was normal. Repetitive nerve stimulation test of left orbicularis oculi demonstrated a significant decremental response (21%). Serum acetylcholine receptor binding (AChR) antibodies were grossly elevated (4.38 nmol/L; normal: <0.4 nmol/L) which confirmed the diagnosis of acquired autoimmune ocular myasthenia gravis. The infant was started on pyridostigmine (2 mg/kg/day) along with oral prednisolone (1 mg/kg) and the ptosis improved dramatically within one month of follow-up [Figure 1]b. Myasthenia gravis refers to the neuromuscular disorder of autoimmune aetiology, affecting skeletal muscles. The onset can vary from 1 month of life to 19 years of age, depending on the racial differences and geographical locations., Typically, if the onset is less than 2 years, it is called infantile myasthenia and juvenile myasthenia gravis (JMG) thereafter. Differentiation between congenital myasthenic syndrome and early-onset JMG becomes challenging, whenever onset of symptoms occur in first 2 years of life. Another concern is false negativity of AChR antibodies in early onset JMG. Certain clues such as asymmetric onset of ptosis, no familial occurrence, presence of autoimmune antibodies, and response to acetylcholinesterase inhibitors point toward autoimmune etiology. To conclude, JMG must be ruled out in any child presenting with ptosis, regardless of age.
|Figure 1: a) Clinical photograph of the child showing ptosis of the bilateral eyelids. b) Clinical photograph of the same child showing improvement of the ptosis after administration of pyridostigmine|
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The authors thank the parents of the patient for images and adding to the literature.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
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