NEURO-SPECIFIC BLOOD PROTEINS IN THE DIAGNOSIS OF PRECLINICAL FORMS OF DIABETIC DISTAL POLYNEUROPATHY

Objective: to assess the information value of laboratory markers of nervous tissues to diagnose preclinical variants of distal diabetic polyneuropathy. Material and methods. We examined patients (n = 181) who were divided into 2 groups: the main group (n = 81) with the verified diagnosis of diabetes mellitus (DM) and the comparison group (n=100) without any endocrine pathology. The results having obtained in the main group were compared depending on the preclinical form of distal diabetic polyneuropathy detected on the basis of the electroneuromyography data: sensory form (group 1, n = 49) and sensor-motor form (group 2, n = 32). The levels of neuro-specific proteins: neuron-specific enolase (NSE), protein S 100 were determined in the blood of the patients. Results. It has been found that the NSE level in the patients of the main group was mainly within 0.17 and 2 ng/ml and, more rarely, within 2.07 and 6.93 ng/ml. The range of normal NSE values in the patients of the comparison group was mainly within 8.01 and 12.0 ng/ml. The ranges of S 100 protein values did not differ in patients with DM or without DM. The threshold value of NCE = 1.04 ng/ml has been found, which makes it possible to perform a differential diagnosis of the preclinical forms of distal diabetic polyneuropathy (groups 1 and 2) with sensitivity and specificity of 85.7%; (± 95% CI: 72.8-94.1) and 78.1% (± 95% CI: 60.0-90.7), respectively. Conclusion The level of NSE is a sensitive marker of distal diabetic polyneuropathy which allows to detect the development of distal diabetic polyneuropathy during the preclinical stage, as well as to perform a differential diagnosis of sensory and sensor-motor preclinical forms.