Clinical, genetic characteristics and follow-up in 14 patients with transthyretin familial amyloid polyneuropathy / 中华神经科杂志

ABSTRACT

Objective:To summarize the clinical and genetic characteristics in patients with transthyretin familial amyloid polyneuropathy (TTR-FAP).Methods:Fourteen unrelated TTR-FAP patients diagnosed at Xuanwu Hospital, Capital Medical University from September 2014 to February 2022 were retrospectively reviewed. The clinical manifestation, electrophysiology, cardiac function, biopsy and gene mutation were analyzed.Results:In the 14 patients (13 males, 1 female) diagnosed as TTR-FAP, the mean age at onset was 53.9 years (range 33.0-71.0 years), with a mean course from symptom-onset to diagnosis of 4.1 years. The late-onset type occurred in 9 cases. Seven patients had a family history of TTR-FAP. Distal paresthesia of lower limbs was the commonest initial symptom (8 cases), with sensorimotor neuropathy and autonomic dysfunction seen initially in 4 and 2 cases, respectively. Cardiac involvement occurred in 6/8 of the patients. Nerve conduction studies indicated extremely axonal impairment with demyelinating features. Sural nerve biopsies showed moderate to severe axonal loss of myelinated fibers and the positive rate of Congo red staining was 8/14. Of 8 different TTR mutations detected, V50M was the most common (appearing in 5 cases). No obvious neuropathy progression was seen in the 5 patients who received tafamidis and 2 patients died of dyscrasia. Conclusions:TTR-FAP is more common in males, with sensorimotor axonal polyneuropathy, autonomic dysfunction and cardiac subclinical damage as the predominant symptoms. V50M is the commonest mutation. Tafamidis can delay the progression of disability.