[Amyloid goiter].

Amyloid goitre, defined as diffuse hyperplasia of the thyroid due to infiltration of amyloid substance, has been rarely reported as in confirmed by the latest reviews of the literature. This paper reports the case of a 23-year-old patient with a long history of systemic amyloidosis probably secondary to a Mediterranean fever with diffuse lymphoadenopathy, hepatosplenomegaly and chronic renal insufficiency, who was referred to our attention due to a struma which had increased in volume over the past few years. Aspirated needle biopsy showed the presence of amyloid and the patient underwent total thyroidectomy; the histological test confirmed amyloid struma. The postoperative evolution was normal and characterised by a slight but transient deterioration of renal function. The authors stress the importance of cytological tests using aspirated needle biopsy under polarised light and after Congo Red staining; this is the only test which enables a preoperative diagnosis to be made, thus conditioning the choice of surgery, even if full thyroidectomy is almost certain given the size of the goitre and the systemic pathogenesis of amyloidosis.