A compound score to screen patients with hereditary transthyretin amyloidosis

• Published in: Journal of neurology Vol. 269; no. 8; pp. 4281 - 4287
• Main Authors: Tozza, Stefano, Severi, Daniele, Spina, Emanuele, Di Paolantonio, Andrea, Iovino, Aniello, Guglielmino, Valeria, Aruta, Francesco, Nolano, Maria, Sabatelli, Mario, Santoro, Lucio, Luigetti, Marco, Manganelli, Fiore
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2022; Springer Nature B.V
• Subjects: Amyloidosis; Carpal tunnel syndrome; Medicine; Medicine & Public Health; Nerves; Neurology; Neuroradiology; Neurosciences; Original Communication; Patients; Peripheral neuropathy; Polyneuropathy; Transthyretin; TTR amyloidosis; Carpal tunnel syndrome; Screening tool; Neuropathy; Neurophysiology
• ISSN: 0340-5354; 1432-1459; 1432-1459
• DOI: 10.1007/s00415-022-11056-4

Background Hereditary transthyretin amyloidosis (ATTRv) is a rare, debilitating and fatal disease, mostly characterized by progressive axonal peripheral neuropathy. Diagnosis is still challenging and diagnostic delay in non-endemic area is about 3–4 years. The aim of this study was to arrange a clinical and electrophysiological score to select patients with axonal neuropathy that deserve screening for TTR mutation. Methods Thirty-five ATTRv patients and 55 patients with chronic idiopathic axonal polyneuropathy (CIAP) were retrospectively analyzed. Clinical and electrophysiological findings at first evaluation were collected. Based on significant results between the two groups, a compound (clinical and electrophysiological) score was arranged, and ROC analysis was performed to identify the ideal cut-off able to discriminate between the two groups. Results ATTRv patients presented a later age at onset, more frequent muscle weakness and carpal tunnel syndrome history. On the other hand, electrophysiological analysis showed that ATTRv patients had lower CMAP and SAP amplitude in all examined nerves. We arranged a compound score constituted by 7 total items, ranging from 0 to 12. ROC analysis showed an Area Under the Curve = 0.8655 and we set the cut-off ≥ 5 points to discriminate ATTRv patients with a sensitivity of 96.6% and a specificity of 63.6%. Conclusion Our study demonstrated that our compound score with cut-off ≥ 5 allows to discriminate ATTRv patients among subject affected by axonal polyneuropathy with a sensitivity > 95%. Thus, our compound score is a quick, easy and effective screening tool.