A new screening tool for early recognition of ATTRv polyneuropathy in clinical practice: AmyloScan^®

Hereditary transthyretin (ATTRv) amyloidosis is a progressive multisystem disorder, mainly characterized by cardiac dysfunction and polyneuropathy. Due to its rarity and heterogeneous presentation, diagnosis is often delayed, which has a direct impact on the initiation of treatment and, therefore, span and quality of life. To facilitate early disease recognition, we aimed to develop and validate a new screening tool for early identification of ATTRv amyloidosis with polyneuropathy (AmyloScan^®). Potential disease characteristics were identified via literature screening, interviews and detailed examination of ATTRv amyloidosis patients (n = 10) and controls (CIDP: chronic inflammatory demyelinating polyneuropathy, n = 15; diabetic polyneuropathy, n = 15) using validated questionnaires, and autonomic and sensory testing. The preliminary AmyloScan® was developed and validated in patients with polyneuropathy caused by ATTRv amyloidosis (n = 21), CIDP (n = 19), or others (n = 43). By sensitivity and discriminant analyses, we determined the most characteristic item combinations for ATTRv amyloidosis. Cut-off values were defined by Receiver Operator Curves. The final AmyloScan® includes 12 questions and two sensory bedside tests. All items require simple yes/no answers, resulting in a total score of 0-14 points and two cut-off values: A value of ≥ 4 indicates an increased chance (sensitivity: 95.2%, specificity: 72.6%); a value of ≥ 6 indicates a high chance of ATTRv polyneuropathy (sensitivity: 81.0%, specificity: 93.5%). The AmyloScan^® is a simple time- and cost-efficient screening tool with a high discriminative value. Regular use in clinical practice might enable an earlier diagnosis with impact on treatment considerations and quality of life.