Which systemic condition is a recognized cause of macroglossia (tongue enlargement)?

Amyloidosis is a systemic condition characterized by extracellular deposition of amyloid fibrils in various organs and tissues. In the oral cavity, amyloid deposition in the tongue causes macroglossia — one of the classic oral manifestations of systemic amyloidosis. Other causes of macroglossia include acromegaly, hypothyroidism (myxedema), Down syndrome, vascular malformations (hemangioma/lymphangioma), Beckwith-Wiedemann syndrome, and neoplastic infiltration. Scleroderma does not typically cause macroglossia; it tends to cause microstomia and a firm, bound-down tongue appearance.