Journal Article

Anti-cN1A Antibodies Are Associated with More Severe Dysphagia in Sporadic Inclusion Body Myositis

Garibaldi, Matteo, Siciliano, Gabriele, Valentino, Maria Lucia, Mirabella, Massimiliano, Tasca, Giorgio, Filosto, Massimiliano, Rodolico, Carmelo, Antonini, Giovanni, Pegoraro, Elena, De Arcangelis, Valeria, Lucchini, Matteo, De Fino, Chiara, Maggi, Lorenzo

2021

Overview

In recent years, an autoantibody directed against the 5′-citosolic nucleotidase1A (cN1A) was identified in the sera of sporadic inclusion body myositis (s-IBM) patients with widely variable sensitivity (33%–76%) and specificity (87%–100%). We assessed the sensitivity/specificity of anti-cN1A antibodies in an Italian cohort of s-IBM patients, searching for a potential correlation with clinical data. We collected clinical data and sera from 62 consecutive s-IBM patients and 62 other inflammatory myopathies patients. Testing for anti-cN1A antibodies was performed using a commercial ELISA. Anti-cN1A antibodies were detected in 23 s-IBM patients, resulting in a sensitivity of 37.1% with a specificity of 96.8%. Positive and negative predictive values were 92.0% and 60.6%, respectively. We did not find significant difference regarding demographic variables, nor quadriceps or finger flexor weakness. Nevertheless, we found that anti-cN1A-positive patients presented significantly lower scores in IBMFRS item 1 (swallowing, p = 0.045) and more frequently reported more severe swallowing problems, expressed as an IBMFRS item 1 score ≤ 2 (p < 0.001). We confirmed the low sensitivity and high specificity of anti-cN1A Ab in s-IBM patients with a high positive predictive value. The presence of anti-CN1A antibodies identified patients with a greater risk of more severe dysphagia.

• Publisher: MDPI AG,MDPI
• Subject: Age / anti-cN1A antibodies / Antibodies / Autoantibodies / Disease / Dysphagia / Immunoglobulins / inclusion body myositis / Inflammation / inflammatory myopathies / Myositis / Quadriceps muscle / Serology / Swallowing