Early recognition of diabetic neuropathy: evaluation of a simple outpatient procedure using thermal perception.

OBJECTIVE To determine the effectiveness of Tip-therm, a temperature discriminator, in making an early diagnosis of distal symmetrical polyneuropathy in diabetic patients and to compare its effectiveness with the Semmes-Weinstein monofilament and biothesiometry, which are established methods of diagnosing neuropathy in diabetic patients. PATIENTS AND METHODS From the diabetic subjects who came to the hospital for review, 910 consecutive cases were selected. All were tested with the Semmes-Weinstein monofilament (10 g monofilament) and biothesiometry and also by using the Tip-therm for comparison. RESULTS Out of the 241 patients who had no sensation to the monofilament only four (1.7%) felt Tip-therm whereas 237 (98.3%) patients could not feel Tip-therm. Among 298 patients diagnosed as having neuropathy by biothesiometry, only eight (2.7%) patients exhibited sensation with Tip-therm while 290 (97.3%) patients could not feel it. CONCLUSION A simple device, Tip-therm, which tests for temperature discrimination, was compared with two validated methods for detection of neuropathy-a monofilament and biothesiometry. Tip-therm appears to be an inexpensive, highly sensitive, and specific device for detection of diabetic neuropathy when compared with biothesiometry and a monofilament.