Electroneuromyographic Features in Fabry Disease: A Retrospective Review.

INTRODUCTION: Fabry disease (FD) is an X-linked recessive inherited disorder characterized by lysosomal alpha-galactosidase deficiency. The purpose of our study was to assess and compare the electroneuromyographic (ENMG) findings of 15 patients with Fabry disease and the electroneurographic (ENG) findings of 15 healthy controls. We have not encountered any similar study in the medical literature of our country. Therefore, we believe that our study will contribute to national literature. METHODS: Fifteen patients with Fabry disease, 13 females and 2 males and 15 healthy controls, 13 females and 2 males, were included in the study. The definite diagnosis of patients with Fabry disease was made based on the enzyme level and genetic mutation. The patients with Fabry disease were examined with ENMG, while the healthy control group was examined with ENG. In the patients with a normal ENMG examination, neuropathic pain was attributed to the small fiber involvement. RESULTS: Patients with Fabry disease had neuropathic pain (LANSS score≥12). While neurological examination was normal in eight patients, glove- and stocking-type hypoesthesia and decreased deep tendon reflexes were observed in five and two patients, respectively. Axonal polyneuropathy was detected in one patient. The ENMG examinations of the other patients were normal. Enzyme replacement therapy could not be initiated in one patient because of pregnancy. The neurological examination of the healthy control group was normal. There was no statistically significant difference between the ENMG features of both groups (p>.05). As in other studies, a routine ENMG examination was normal in our patients with early-stage Fabry disease. Neuropathic pain, seen in patients with Fabry disease in literature, is thought to be due to small fiber involvement. CONCLUSION: Fabry disease should be considered in the differential diagnosis of patients with neuropathic pain at young ages. It should be kept in mind that ENMG examination can be normal at the early stages. Quantitative sensory test, autonomic tests (R-R interval and sympathetic skin response) and skin biopsy should be performed in such cases. In our country, pediatric physicians work on Fabry disease more than physicians dealing with Fabry disease in adults. Therefore, in this retrospective study, we aimed to draw adult and pediatric neurologists' attention to Fabry disease.

Visual evoked potentials in differential diagnosis of multiple sclerosis and neurobehcet's disease.

Behcet's disease, a multisystemic vascular inflammatory disorder of unknown origin, is relatively rare and central nervous system involvement is seen in 5% of affected individuals. This form of the disease, called as neurobehcet's disease (NB), can be misdiagnosed as multiple sclerosis (MS), a demyelinating disorder of central nervous system, so their differential diagnosis is important. In this study, to identify the parameters of electrophysiological testing that might be useful in their differential diagnosis, we performed evoked potentials (EPs) and electroneuromyography (ENMG) on patients with MS and NB, and on normal volunteers. A total of 95 persons, 55 MS patients, 20 NB patients and 20 normal volunteers between ages 31 and 55, were studied electrophysiologically. Visual evoked potential (VEP), brainstem auditory evoked potential (BAEP), posterior tibial somatosensory evoked potential (SEP) and nerve conduction and needle electromyography studies were performed on all patients and volunteers. All parameters of EPs were compared among the groups. The results of the BAEP and SEP studies did not show statistically significant difference between NB and MS. However, the VEP study indicated that the amplitude values of cortical VEP potentials (P100) in the NB and MS groups were lower than those of the normal group (p < 0.01), and that the amplitudes in the NB group were lower than for the MS group (p < 0.05). Therefore, P100 amplitude measured from peak to peak seems to be more reliable and thus should be used in the differential diagnosis of MS and NB.

Hypothyroid myopathy with manifestations of Hoffman's syndrome and myasthenia gravis.

Although hypothyroid myopathy is seen frequently and the relationship with autoimmune hypothyroidism and myasthenia gravis is well known, specific forms of hypothyroid myopathy such as Hoffman's syndrome (HS) are rarely described. Here we describe a 40-year-old patient with Hashimoto thyroiditis showing symptoms and signs of two discrete forms of hypothyroid myopathy (HS and myasthenic syndrome) together. To our knowledge this is the first reported case with features of both of these syndromes. We discuss the diagnosis, speculate whether this patient may represent a unique form of hypothyroid myopathy, and report the 6-month follow-up of the patient both clinically and electrophysiologically.