Outcome of liver transplantation for transthyretin amyloidosis: follow-up of Japanese familial amyloidotic polyneuropathy patients.

Since 1990, liver transplantation for familial amyloidotic polyneuropathy (FAP) has been carried out world-wide, and the outcome of the procedure seems to be promising. FAP is inherited systemic disease caused by mutated transthyretin. The most common cause is the valine to methionine substitution at position 30 (Met30). We have developed a scoring system for FAP Met30 that takes into account a variety of clinical symptoms of the disease. Six patients with FAP Met30 underwent extensive examinations according to our scoring system before and after transplantation. All patients survived the procedure and are alive after transplantation. Improvements of sensory and autonomic disturbances were observed during the initial 12 months after the procedure only, thereafter the patients' status remained unchanged. Following transplantation, no improvement of motor function and visceral organ damage were observed, but the modified body mass index improved in four of six patients after the operation. These results suggest that liver transplantation of FAP patients stops the progress of the disease, and that minor improvements are noted in several patients after the procedure. However, transplantation should be performed early after the onset of the disease in order to preserve the patients' functional status.