When Surgical Intervention Becomes a Risk: Severe Drug-Induced Gingival Overgrowth and Clinical Decision-Making in Alpers-Huttenlocher Syndrome.

INTRODUCTION: Alpers-Huttenlocher syndrome (AHS) is an ultra-rare, autosomal recessive mitochondrial encephalopathy caused by pathogenic POLG variants, characterized by refractory epilepsy, hepatic dysfunction, and progressive neurodegeneration. Drug-induced gingival overgrowth (DIGO) is a recognized complication of anticonvulsant and immunosuppressive therapy, particularly in medically complex patients. This report describes severe DIGO in a child with genetically confirmed AHS and explores the implications for multidisciplinary dental management. METHODS: A CARE-compliant case analysis was conducted in a five-year-old girl with AHS, status post living-donor liver transplantation, chronically hospitalized in a long-term intensive care unit. Clinical findings, pharmacologic exposures, multidisciplinary decision-making, and conservative oral management strategies were systematically documented. RESULTS: The patient, ventilator-dependent and gastrostomy-fed, had prolonged exposure to phenytoin, sodium valproate, topiramate, and tacrolimus without prior dental surveillance. Examination revealed severe fibrotic maxillary gingival overgrowth, delayed tooth eruption, and functional compromise. Given her profound systemic fragility, gingivoplasty under general anesthesia was contraindicated. A structured conservative protocol including 0.12% chlorhexidine, mucosal care, and continuous dental follow-up was implemented to reduce inflammatory and infectious burden. CONCLUSION: This case underscores the necessity of integrating dental care into the multidisciplinary management of rare mitochondrial disorders and represents, to our knowledge, the first reported association between AHS and severe DIGO.