Established electrophysiological methods have limited clinical utility in the diagnosis of small‐fiber neuropathy (SFN). In this study, diabetic patients with clinically diagnosed SFN were evaluated with autonomic tests and cutaneous silent periods (CSPs). Thirty‐one diabetic patients with clinically suspected SFN and normal nerve conduction studies were compared with 30 controls. In the upper extremities (UE), the CSP parameters did not differ statistically between the patient and control groups, whereas, in the lower extremities (LE), patients had prolonged CSP latencies (P = 0.018) and shortened CSP durations (P < 0.001). The sensitivity of the CSP duration was 32.6%, and the specificity was 96.7%. The expiration‐to‐inspiration ratios and amplitudes of the sympathetic skin responses in the lower extremities were also reduced. Our findings indicate that the diagnostic utility of CSPs was higher than that of the autonomic tests to support the clinically suspected diagnosis of SFN. Muscle Nerve, 2011

Pandysautonomia is a severe and rare clinical condition characterized by widespread sympathetic and parasympathetic dysfunction. Consideration of whether symptoms and presentation are acute, subacute, or chronic is often helpful in establishing a differential diagnosis. The underlying mechanisms leading to pure pandysautonomia are unclear; however, there is some evidence suggestive of an immune-mediated pathogenesis. Herein, we report a case with pandysautonomia as a paraneoplastic manifestation of non-small cell lung cancer that had an excellent response to symptomatic and supportive treatments, as well as IVIG therapy.

objective: Clinical utility of nerve conduction studies (NCS) of the medial plantar and dorsal sural nerves in the early detection of polyneuropathy have already been shown separately. However, at present, there is no data about the combined assessment of these two nerves in distal sensory neuropathy. In the present study, we aimed to evaluate the medial plantar and dorsal sural NCS in a group of diabetic patients with distal sensory neuropathy (DSN) and in healthy controls.Methods: Thirty healthy and 30 diabetic adult patients were included. In all subjects, peripheral motor and sensory NCS were performed bilaterally with surface electrodes on the lower limbs including medial plantar and dorsal sural nerves. In addition, motor and sensory nerves were studied unilaterally on the upper limb.Results: In all patients, nerve action potential (NAP) amplitudes of sural and superficial peroneal nerves were within normal ranges, but in the patient group mean value was significantly lower than in the controls. Among clinically defined 30 DSN patients, medial plantar NAP amplitude was abnormal in 18 (60%) and dorsal sural nerve amplitude was abnormal in 13 (40%) of the patients bilaterally. Additionally, the onset NCV of the dorsal sural nerve was significantly slower in patients than controls (P = 0.038). Evaluation of both of these nerves increased the sensitivity up to 70% in the detection of neuropathy.Conclusions: Bilateral NCS assessment of both of the medial plantar and dorsal sural nerves together increases the rate of diagnosis of diabetic distal sensory neuropathy compared to assessment of either of these nerves.Significance: Assessment of medial plantar in addition to dorsal sural NCS together increases the sensitivity in the detection of neuropathy and allows earlier diagnosis, especially when routine NCS are normal. (c) 2008 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.