Risk of transmission of systemic transthyretin amyloidosis after domino liver transplantation.

Recent reports of the transmission of systemic transthyretin (TTR) amyloidosis after domino liver transplantation (DLT) using grafts from patients with familial amyloid polyneuropathy (FAP) have raised concerns about the procedure. The aim of this study was to evaluate the transmission incidence of systemic TTR amyloidosis after DLT with a complete clinical, neurological, and pathological assessment. At our institution, DLT has been performed 31 times with livers from patients with FAP. Seventeen of the 19 patients still alive in 2008 agreed to enter the study. This cross-sectional study of this cohort of patients included clinical assessments, rectal biopsy, and electroneuromyography (as well as sural nerve biopsy when it was indicated). The mean follow-up at the time of the study was 62.6 ± 2.9 months. Clinically, 3 patients complained of weak dysesthesia. When a focused study was performed, 8 patients reported some kind of neurological and/or gastrointestinal disturbance. Six of the rectal biopsy samples showed amyloid deposits (TTR-positive). Electromyography (EMG) showed signs of mild sensorimotor neuropathy in 3 cases and moderate to severe sensorimotor neuropathy in 1 case. Only 2 of the 4 patients with EMG signs of polyneuropathy showed amyloid deposits in their rectal biopsy samples. Sural nerve biopsy revealed amyloid deposits (TTR-positive) in all 4 patients with EMG signs of polyneuropathy. Two patients with normal EMG findings had TTR-positive amyloid deposits in their sural nerve biopsy samples. In conclusion, de novo systemic amyloidosis after DLT may be more frequent and appear earlier than was initially thought. In our opinion, however, the graft shortage still justifies DLT in selected patients, despite the risk of de novo systemic amyloidosis. Sural nerve biopsy with EMG and clinical correlation is mandatory for confirming the disease. Indeed, other causes of neuropathy should be excluded.