Adult-onset acid maltase deficiency with isolated axial muscle involvement.

INTRODUCTION

We report a patient with acid maltase deficiency who presented with subacute respiratory failure as the first symptom without significant extremity weakness.

METHODS AND

RESULTS

Electromyography of extremities was normal but showed myopathic changes and myotonic discharges limited to axial muscles only. Muscle biopsy confirmed the diagnosis.

CONCLUSION

It is essential to examine axial muscles during electromyography if a patient presents with respiratory failure of unclear etiology even if the clinical examination does not show significant weakness in the extremities and electromyographic findings in the extremities are unremarkable.