Myasthenia gravis(MG) is an autoimmune disorder characterized by muscle weakness and fatigability [1,2,3]. It is due to autoantibodies causing receptor depletion at the neuromuscular junction, which results in impaired acetylcholine function [2,4]. It causes impaired nerve function and muscle weakness [1,3,5]. Myasthenia gravis can be generalized or localized as ocular myasthenia gravis [3,4,6].

Juvenile myasthenia gravis (JMG) is a rare condition and is distinct from adult-onset disease [4,7]. Ocular myasthenia is characterized by easy fatigability of extraocular muscles, commoner in females. Diagnosis is the Tensilon test or Neostigmine test, clinically [1,8]. Investigations include acetylcholine receptors autoantibodies titers. Treatment includes the use of anticholinesterase, immunosuppressants, plasmapheresis, and thymectomy when indicated [6,7,9,10].

An 8-year-old boy presented with a history of drooping of upper lids of both eyes for 10 days. It was more in the left eye than the right eye. It was acute in onset and progressive. His mother had noticed that the drooping of upper lids was not constant and was not present as soon as the boy opened his eyes, after his sleep.

It worsened as the day progressed. He also started complaining of double vision for the past 8 days, which was variable and was not present in any particular gaze. He didn’t have any trauma before these symptoms developed. There was no associated fever or headache. His vision was good before and after his illness. He had no difficulty in breathing or swallowing or drooling of saliva. He did all his routine chores by himself and played well.

He didn’t feel tired or the week after exertion. There was no history of pain around the eyes or other facial muscles. There was no history of abnormal jerks or movements of the facial muscles. Pregnancy and neonatal histories were unremarkable. All aspects of motor development were normal. He was doing well academically. There was no similar illness in the family.

On examination, the boy was conscious cooperative, and well oriented to time, place, and person. His vitals were stable.

Fig-2: Extraocular movements were restricted and showed a fluctuating pattern.

Intraocular pressure was done by applanation tonometry was 12mmHg in both the eyes. Clinical diagnosis of Ocular myasthenia gravis was made and an Edrophonium test was done and it showed significant improvement.

Complete blood count, Erythrocyte sedimentation rate, thyroid function test, blood sugar levels were normal. CT chest showed no thymoma. Thyroid function tests (T3, T4, and TSH) done were within the normal range.

Treatment: He was commenced on oral Neostigmine at a dose of 2mg/Kg/ day,4 hourly in divided doses and is on regular follow up and had a good response.

It can occur at any age. It differs from adult-onset except that it frequently improves with age. The most common presentation is ptosis next common is diplopia in MG. these symptoms worsens as the day progresses. Other symptoms of generalized MG are slurred speech, dysphagia, feeling week, dyspnea, dysarthria.

Diagnostic tests are needed to confirm clinical suspicion include anti-AChR antibodies, electromyography (EMG) repetitive nerve stimulation (RNS) test, edrophonium tests [6]. Associated conditions including thymoma and thymic hyperplasia should be ruled out with appropriate investigations such as chest CT scan

Both ocular and generalized myasthenia gravis patients tend to have remissions and exacerbations at regular intervals. Treatment includes both medical and surgical6,8. Medications may include cholinesterase inhibitors such as Mestinon, steroids such as Prednisone, or other immunosuppressants used alone or in combination. Other modalities of treatment include plasmapheresis or IVIG (intravenous immunoglobulin) therapy which can be used either individually or in combination with other treatments [9].

These treatments offer only a temporary improvement and repeated treatments are necessary to sustain the effect. While thymectomy (removal of the thymus gland) is often recommended for patients with generalized MG, it is rarely used in purely ocular MG unless a thymoma is suspected [5,10].

Ocular myasthenia gravis is most likely to progress to generalized myasthenia, so regular follow up is required.

Ethics and consent

Written/ signed informed consent was obtained from the patient for the publication of this case and accompanying images. The patient’s confidentiality was also maintained throughout.