GAD2 and autoimmune disease: Among the 40 IMCAs with definite etiology, 14 patients (25.9%) were identified as anti-NSAbs associated CAs, followed by PCD (13 patients, 24.1%), anti-GAD65-Ab-associated CAs (7 patients, 13.0%), and autoimmune disease-associated CAs (6 patients, 11.1%) (Table 1).