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Familial infantile myasthenia: a diagnostic problem
J W Matthes1, A P Kenna, P R Fawcett
1Department of Paediatrics, Newcastle General Hospital, Newcastle upon Tyne.
Developmental Medicine and Child Neurology
|October 1, 1991
Summary
Diagnosing familial infantile myasthenia is challenging, even with normal nerve studies. Early diagnosis and treatment with pyridostigmine improved one sibling
Area of Science:
- Pediatric Neurology
- Clinical Electrophysiology
- Rare Genetic Disorders
Background:
- Familial infantile myasthenia is a rare neuromuscular disorder presenting with significant diagnostic challenges.
- Recurrent apnoeic attacks in infants can stem from various causes, necessitating comprehensive diagnostic approaches.
Observation:
- Two siblings presented with recurrent apnoeic attacks suggestive of familial infantile myasthenia.
- Standard repetitive nerve stimulation studies were unremarkable in both affected siblings.
- Electromyography revealed subacute neurogenic changes in one sibling, while tracheomalacia was identified in the other.
Findings:
- Diagnostic difficulties were encountered due to normal initial electrophysiological tests.
- A positive decremental response on nerve stimulation was only observed in one sibling after prolonged stimulation.
- One sibling with tracheomalacia unfortunately succumbed to hypoxic brain damage following an apnoeic episode.
Implications:
- This case highlights the diagnostic complexities of familial infantile myasthenia, emphasizing the need for advanced electrophysiological techniques.
- Timely diagnosis and appropriate treatment, such as pyridostigmine, can significantly improve outcomes for affected infants.
- The co-occurrence of tracheomalacia underscores the importance of considering concurrent respiratory and neurological conditions in infants with apnoea.
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