Quantified sensory abnormalities in early genetically verified transthyretin amyloid polyneuropathy

• Published in: Muscle & nerve 2007-02, Vol.35 (2), p.189-195
• Main Authors: Heldestad, Victoria, Nordh, Erik
• Format: Article
• Language: English
• Subjects: Adult; Age Factors; Amyloid Neuropathies - complications; Amyloid Neuropathies - genetics; Amyloid Neuropathies/complications/genetics; amyloidosis; Biological and medical sciences; Cranial nerves. Spinal roots. Peripheral nerves. Autonomic nervous system. Gustation. Olfaction; Diseases of striated muscles. Neuromuscular diseases; Female; Humans; Male; Medical sciences; Methionine - genetics; Nervous system (semeiology, syndromes); Neurology; Peripheral Nerves - physiopathology; Prealbumin - genetics; QST; quantitative sensory testing; Sensory Thresholds - physiology; small-fiber neuropathy; Somatosensory Disorders - etiology; Somatosensory Disorders - genetics; Somatosensory Disorders/etiology/genetics; Temperature; thermal thresholds; transthyretin; Valine - genetics
• ISSN: 0148-639X; 1097-4598; 1097-4598
• DOI: 10.1002/mus.20689

Transthyretin amyloid neuropathy of type 1 (Swedish–Portuguese type) is an autosomally inherited progressive disease with a Val30Met mutation, causing generalized sensory‐motor polyneuropathy. Quantitative sensory testing (QST) quantifies thermal threshold changes in patients with manifest general polyneuropathy, but its applicability at an early clinical stage of a strict biochemically defined disease has not yet been shown. Thermal QST was performed in 23 patients having a positive Val30Met marker and clinical symptoms of peripheral small‐fiber neuropathy but normal electrophysiological findings and compared to a reference group of 43 healthy volunteers, both subdivided into age groups ≤45 and >45 years. Significant differences between patients and controls were found at all test sites in both age groups, except for warm thresholds at the medial lower leg in those >45 years. QST thus demonstrated elevated thermal thresholds before the development of electrophysiological abnormalities, which indicate large‐fiber involvement. These findings confirm that QST is a useful method for documentation of developing polyneuropathy. Muscle Nerve, 2006