Myxedema Coma in Neuronal Ceroid Lipofuscinosis Type 6: a life-threatening complication in a rare disease

Background Myxedema coma is a rare endocrine emergency with high mortality. Its occurrence in adolescents is exceptionally rare. Neuronal Ceroid Lipofuscinosis Type 6 (CLN6), commonly known as Batten disease, is a fatal genetic pediatric neurodegenerative disorder. While neurological symptoms dominate, associated endocrinopathies are not well-characterized. This report describes the first case of myxedema coma in an adolescent with CLN6 disease. Case presentation A 16-year-old male with end-stage CLN6 disease (confirmed homozygous CLN6 deletion), ventilator-dependent and in a persistent vegetative state, was transferred with acute abdominal distension, facial swelling, bradycardia (58 bpm), and hypothermia (36.2°C). He had known central hypothyroidism. Admission labs confirmed profound hypothyroidism (TSH 0.015 mIU/L, fT4 7.7 pmol/L). Abdominal CT revealed colonic pseudo-obstruction. A diagnosis of myxedema coma was made. He was treated successfully with intravenous levothyroxine and stress-dose hydrocortisone, the latter due to a borderline ACTH stimulation test suggesting adrenal insufficiency. Conclusions This case illustrates that patients with severe neurodegenerative disorders like CLN6 are at risk for life-threatening endocrine emergencies. Central hypothyroidism in this context can precipitate myxedema coma, a diagnosis complicated by the patient's underlying neurological baseline. Proactive endocrine surveillance is crucial in this population to prevent catastrophic outcomes.