Amyloid Goiter as the Initial Manifestation of Systemic Amyloidosis due to Familial Mediterranean Fever with Homozygous MEFV Mutation

Abstract

We describe a case of amyloid goiter revealing a systemic amyloidosis secondary to familial Mediterranean fever (FMF) with homozygous MEFV mutation, and we review the literature. A 45-year-old euthyroid Sephardic man, known to suffer from FMF, developed a goiter with cold nodule, after which a subtotal thyroidectomy was performed. Histologic evaluation revealed diffuse AA amyloid deposition without any associated thyroid neoplasia. At that time, no other organ was found to be affected by amyloidosis. Colchicine and levothyroxine were prescribed. Eight years later, the patient presented with a rapidly growing neck enlargement. He reported that he had discontinued colchicine therapy 2 years earlier. The serum thyrotropin (TSH) and calcitonin levels were normal. Renal, digestive, and salivary gland biopsies confirmed the presence of systemic AA amyloidosis. Despite the reintroduction of colchicine, the onset of compressive symptoms led to the completion of the total thyroidectomy. The histopathology again demonstrated amyloid deposition, and excluded a malignant neoplasm. Nine cases of amyloid goiter associated with FMF have been reported in the literature; none of them had an amyloid goiter as the first manifestation of systemic amyloidosis. To our knowledge, this is the first case of FMF in which an amyloid goiter preceded the development of secondary systemic amyloidosis. The cessation of colchicine therapy may have played a role in local relapse and the secondary spread of amyloid deposits.