Small fiber neuropathy associated with hyperlipidemia: utility of cutaneous silent periods and autonomic tests.

Background. Established electrophysiological methods have limited clinical utility in the diagnosis of small fiber neuropathy. The cutaneous silent period (CSP) may be useful as a method for the evaluation of smaller and unmyelinated fiber dysfunctions. Hyperlipidemia is a very rare cause of small fiber neuropathy. In this study, hyperlipidemia and small fiber neuropathy in symptomatic patients with normal nerve conduction studies were evaluated with autonomic tests and cutaneous silent periods. Methods. Twenty-five patients with clinically suspected small fiber neuropathy and 23 healthy volunteers were included. CSP latency and duration, as well as CSP latency difference of the upper and lower extremities, were examined. Two tests were used to assess the autonomic nervous system, namely, the R-R interval variation test in basal and profound breath conditions and the sympathetic skin response. Results. Twenty-five patients with clinically suspected small fiber neuropathy and normal nerve conduction studies were compared with 23 controls. In the upper extremities, patients had prolonged CSP latencies (P = 0.034) and shortened CSP durations (P = 0.039), whereas in the lower extremities, patients had shortened CSP durations (P = 0.001). The expiration-to-inspiration ratios were also reduced in patients groups. There was no significant difference between sympathetic skin response latencies and amplitude of the case and control groups. Conclusion. Our findings indicate that CSP may become a useful technique for the assessment of small fiber neuropathy in hyperlipidemic patients.

The role of event related potentials in evaluation of subclinical cognitive dysfunction in epileptic patients.

BACKGROUND/AIM: Cognitive dysfunction in epileptic patients may develop due to the neurophysiological changes related to seizures or antiepileptic drugs. The aim of this study was to evaluate the cognitive dysfunction in epileptic patients under antiepileptic drug therapy by the aid of event related potentials. METHOD: P300 latencies were obtained from Fz, Cz and Pz electrod positions from both epileptic patients (n=40) and age and sex matched control group (n=40). Epileptic patients were classified either idiopathic primary generalized (IPGE) (n=9) or secondary generalized epilepsy (SGE) (n=31) based on the ILAE classification. The effect of epilepsy type, treatment types (monotherapy/polytherapy), daily dosages and serum levels of antiepileptic drugs, age at onset and EEG abnormalities on P300 latencies were studied. RESULTS: P300 latencies were longer in the epileptics when compared to controls (P < 0.05). Besides, our results pointed out that P300 latencies were longer in IPGE when compared to SGE (P < 0.05). No statistically significant difference was determined between ERP parameters neither in monotherapy nor in polytherapy groups (p > 0.05). Antiepileptic drug subgroups revealed variable effects on ERP latencies. CONCLUSION: We believe P300 latencies may have an important role in the evaluation of subclinical cognitive dysfunction in epileptic patients treated with antiepileptic drugs.

Posterior tibial nerve stimulation for faecal incontinence after partial spinal injury: preliminary report.

BACKGROUND: This study evaluated the possible effects of posterior tibial nerve stimulation in two patients with faecal incontinence due to partial spinal cord injury. METHODS: Posterior tibial nerve stimulation was performed for 30 min, every other day for 4 weeks, and was then repeated every 2 months for three months. Clinical examination, anorectal physiological work-up, faecal incontinence severity index, and quality of life assessments were performed before and after the treatment. RESULTS: After posterior tibial nerve stimulation, patients showed improvement in rectal sensory threshold, pudendal nerve terminal motor latency, Wexner faecal incontinence score, faecal incontinence severity index, faecal incontinence quality of life scales, resting pressure, and maximum squeeze pressure measurements. CONCLUSIONS: Posterior tibial nerve stimulation can be an effective method for the treatment of faecal incontinence caused by partial spinal cord injury.

Cyclosporine-A induced neurotoxicity after renal transplantation.

Cyclosporine-A is a highly potent immunosuppressive agent for solid organ transplantation, but has many side effects including nephrotoxicity, hypertension, gum hyperplasia, hepatotoxicity, and neurotoxicity. Neurotoxicity is a less known toxic effect. The pathogenesis of this effect is unclear. However, it has been postulated that hypomagnesemia, hypocholesterolemia, corticosteroids, and/or neurotoxic substances can induce this syndrome. Also, it has been suggested that the endothelial damage caused by Cyclosporine-A may contribute to neuropeptide-mediated ischemia in the brain and lead to the development of neurological symptoms. In this report, we present a case with reversible neurologic deficits whose symptoms returned to normal after the cessation of cyclosporine-A.