We report on a 38 year old woman of Portuguese origin with peripheral ascending polyneuropathy for several years. Her family history was positive for hereditary systemic amyloidosis. A familial amyloidotic polyneuropathy with a Portuguese type I variant (Val→Met30) of the transthyretin molecule (prealbumin) was diagnosed. In the following months, symptoms worsened, the gait became stepping, and urinary incontinence increased. In order to prevent disease …