Maternally inherited Leigh syndrome: an unusual cause of infantile apnea.

INTRODUCTION: Leigh Syndrome is an uncommon cause of infantile apnea. CASE SUMMARY: We report a 5-month-old girl with sudden respiratory arrest followed by episodic hyper- and hypo-ventilation, encephalopathy, and persistent lactic acidosis. Computed tomography of the brain revealed symmetric low densities over the basal ganglia, internal capsule, thalami, and midbrain. Cardiac echocardiogram was suggestive of hypertrophic cardiomyopathy. DISCUSSION: Diagnosis of Leigh syndrome due to T8993G mutation was confirmed with polymerase chain reaction and direct DNA sequencing of mitochondrial genome. To our knowledge, this is the first report of proven maternally inherited Leigh syndrome in Hong Kong.