Amyloid goiter in cystic fibrosis

Chronic infectious or inflammatory diseases lead to amyloid infiltration and dysfunction of many organs, including the kidney, liver, heart, and gastrointestinal tract. Subclinical amyloid infiltration of the thyroid gland has been described in over 80% of such patients. However, symptomatic involvement of the thyroid gland by amyloid is rare. We describe a euthyroid patient with cystic fibrosis and widespread amyloidosis who presented with a rapidly enlarging goiter and symptoms of local compression that compromised his pulmonary status. Fine needle aspiration of the goiter was nondiagnostic. At surgery he proved to have replacement of the thyroid gland by amyloid. A review of the literature reveals only five previous cases of amyloid goiter in patients with cystic fibrosis. However, as more patients survive into adulthood, amyloid goiter may become a more common complication of cystic fibrosis. In contrast to other patients with reactive amyloidosis and goiter, patients with cystic fibrosis may require thyroid surgery to relieve airway compression that can compromise pulmonary function.