ACTA ENDOCRINOLOGICA (BUC)

Objective. The mechanisms underlying the development of diabetic neuropathic pain (NeP) are still unknown. The aim of the study was to evaluate painful diabetic neuropathy in Type II diabetic patients with Leeds Assessment of Neuropathic Symptoms and Signs Scale (LANSS), thermal and vibratory Quantitative Sensory Testing (QST) and, EMG supported Diabetic Neuropathy Score (DNS) and to evaluate the differences in patients with and without neuropathic pain. Methods. Eighty three Type II diabetic patients (26 males, 57 females) were investigated. Patients with pain were assessed by the LANSS pain scale and a score of ≥12 was classified as NeP. All patients underwent nerve conduction studies (NCS) to obtain EMG supported diabetic neuropathy score (DNS). Cold and warm sensation thresholds and cold pain and heat pain thresholds were obtained for evaluation of A-delta and C type fibers. Vibratory perception thresholds were recorded for evaluation of thickly myelinated fibers. Results. The percentage of NeP (LANSS score ≥12) was 15.7 %. QST revealed significantly lower cold detection, higher warm detection and higher heat pain thresholds at the feet in patients with NeP compared with patients without NeP. Although small fiber dysfunction has been revealed in all patients with NeP, the percentages of the presence of small fiber neuropathy and EMG supported diabetic neuropathy were not significantly different among patients with NeP and without NeP. Conclusions. We concluded that QST is a useful and a noninvasive tool to detect small fiber dysfunction in Type II diabetic patients. QST revealed increased severity of small fiber dysfunction in patients with NeP. Although small fiber neuropathy has been revealed in all Type II diabetic patients with neuropathic pain the absence of pain does not predict preserved small fiber function.