ENO2 and autonomic neuropathy: This study addresses these critical knowledge gaps by providing comprehensive validation of NSE as a biomarker for diabetic neuropathy in an Indian population. This study aims to assess the correlation between serum neuron-specific enolase (NSE) levels and the presence and severity of peripheral neuropathy, while also exploring its potential association with autonomic neuropathy as evaluated through standardised cardiovascular autonomic reflex tests.