Dados do Trabalho

Título

A long-term follow-up of Brazilian patients with transthyretin familial amyloid polyneuropathy after liver transplant

Resumo

Introduction: Transthyretin familial amyloid polyneuropathy (ATTRv-pn) is an inherited neuropathy, with over 140 mutations identified in the transthyretin (TTR) gene. ATTRv-pn is a severe length-dependent sensorimotor/autonomic neuropathy, which if untreated, leads to death in approximately 10 years (y). The liver produces 98% of the TTR circulating in the blood, and it was thought that liver transplant (LT) would stop disease progression. However, subsequent studies showed that the results were not good in late-onset patients (≥ 50y), those who were malnourished, with advanced disease and/or had non-V50M mutations. It proved to be very effective in controlling the neuropathic manifestations, but less effective in controlling cardiac manifestations. Objective: To describe the long term follow up of a series of ATTRv Brazilian patients with polyneuropathy who underwent LT. Method: We have reviewed the medical records of all patients (8) with ATTRv-pn who underwent LT and were followed in our institution. The diagnosis was made by genetic testing. We have used the Composite Autonomic Symptom Score 31 (COMPASS 31) for quantitative measure of autonomic symptoms. Results: All patients had the ATTRv-pn V50M variant. The mean age at symptoms onset was 31,2y. All patients had neuropathic pain before LT, and 2 of them experienced complete pain relief after it. All patients have clinical dysautonomia and the mean of the last COMPASS 31 was 52,6. 50% have confirmed cardiomyopathy; 37,5% are still under investigation and 12,5% do not have it. 87,5% have some arrhythmia or conduction-system disease and 50% needed pacemaker implantation between 2002 and 2022. The mean time from symptoms onset to diagnosis was 2y and from symptoms onset to LT was 5,37y. 6 patients are fully ambulants - Coutinho stage (CS) 1 -, 1 patient needs one walking aid - CS 2 - and 1 patient became wheelchair-bound - CS 3 - in the last 2y. The mean time from symptoms onset to the last clinical evaluation (2022) was 18,2y (8-23y), and from LT to the last clinical evaluation (2022) was 13,5y (6-18y). Conclusion: Our patients have most of the factors for good prognosis cited in the literature, as V50M mutation, early-onset and early-stage disease when they underwent LT. The 20-y patient survival rate was 62,5%, higher than the average in the literature (55,3%). The mean time from symptoms onset to diagnosis was lower than it is in Brazil (5,9y).

Palavras Chave

Transthyretin familial amyloid polyneuropathy; liver transplant