P15.4 Microneurographic evaluation of sympathetic activity in small fiber neuropathy

14th ECCN / 4th ICTMS/DCS Results: All patients presented a SOREMP and stages 1, 2 and 3 NREM sleep whereas only 3 patients displayed stage 4 NREM sleep. The mean total time of SOREMP was 8.3±4.4 minutes whereas for stage 1, 2, 3 and 4 were 6.3±0.6, 12.6±9.3, 3.4±1.5 and 7.8±9.6 minutes respectively. Compared to wakefulness before sleep all patients showed a decrease of MSNA with unchanged BP and HR during SOREMP whereas during stages 1, 2, 3 and 4 MSNA, BP and HR showed a continuous further decrease. Conclusions: These preliminary findings showed that autonomic changes during SOREMP differ from normal REM sleep. These data suggested that SOREMP should not be simple considered as a REM sleep intrusion but the underlying pathogenetic mechanism is probably more complex. P15.2 Sympathetic activity evaluated by microneurography in patients with Ross syndrome V. Donadio1 , M.P. Giannoccaro1 , M. Nolano2 , V. Di Stasi1 , P. Cortelli1 , A. Baruzzi1 , R. Liguori1 1 Department Neurlogical Sciences, Bologna, Italy, 2 Department of Neurology, Salvatore Maugeri Foundation, IRCCS, Telese Terme (BN), Italy Objective: Ross syndrome (RS) is characterized by tonic pupil, areflexia and anhidrosis and the underlying lesion affects postganglionic skin sympathetic nerve fibers whereas postganglionic muscle sympathetic branch is usually spared. Microneurography allows to explore both skin and muscle peripheral sympathetic branches. In chronic dysautonomic syndromes such as pure autonomic syndrome (PAF) microneurography usually did not disclose peripheral sympathetic outflow in both branches. The aim of this study is to confirm the selective involvement of postganglionic skin sympathetic nerve fibers in RS. Methods: We studied 8 patients (50±16 years, 4 males) with typical clinical picture and skin biopsy findings. They underwent to microneurography from peroneal nerve with the recording of muscle sympathetic nerve activity (MSNA), skin sympathetic nerve activity (SSNA) and the corresponding organ effector responses (skin sympathetic response-SSR and skin vasomotor response-SVR) in the same innervation field. The absence of sympathetic bursts was established after exploring at least 3 different corresponding nerve fascicles (i.e. skin for SSNA and muscle for MSNA). Thirty age and sex-matched healthy subjects served as controls. Results: RS patients complained of anhidrosis, abnormalities of accommodation due to tonic pupils and they showed areflexia. All patients displayed absent SSNA, SSR and SVR whereas MSNA was always recorded showing normal characteristics. Conclusions: Microneurographic study of sympathetic activity confirmed the selective involvement of skin sympathetic activity in RS. Microneurography is an useful functional tool contributing to the RS diagnosis. P15.3 Subclinical autonomic neuropathy in infant-juvenile diabetes. A community-based study I. Benavente1 , M.J. Pablo1 , P. Tamargo1 , P. Lalaguna2 , F. Romero1 , M. Ferrer3 1 Department of Clinical Neurophysiology, San Jorge Hospital, Huesca, Spain, 2 Department of Pediatrics, Barbastro Hospital, Barbastro, Spain, 3 Department of Pediatrics, San Jorge Hospital, Huesca, Spain Introduction: Autonomic dysfunction contributes to the morbidity and mortality associated with diabetes. Data regarding the prevalence of the subclinical form in infant-juvenile diabetes are scarce. Some researchers state that autonomic dysfunction appears early and recommend a routine evaluation of autonomic function. Objective: To investigate the prevalence of subclinical autonomic dysfunction in infant-juvenile diabetes in Huesca, a province northern Spain, in order to evaluate the suitability of routinely testing of autonomic function from the early stages of diabetes, and to compare this prevalence with that of subclinical somatic neuropathy. The study is still in progress. We report preliminary results of a five-year follow-up. Methods: From 2006, all patients aged 5 to 19 diagnosed with diabetes, living in this area, are included. So far, we have studied prospectively 45 patients. Since their diagnosis, they are being examined once a year until they reach 19. Forty healthy boys and girls were included as the control group. We evaluate autonomic function by measuring basal heart rate variability, and during deep breathing, standing and in response to

S127 Valsalva maneuver, and by pupilometry. Nerve conduction study is also performed. Results: Five patients had abnormalities in one autonomic test, although none of them met the criteria for subclinical autonomic dysfunction. Three patients fulfilled the criteria for subclinical somatic neuropathy. Conclusion: Preliminary results show a lower prevalence of subclinical autonomic and somatic dysfunction compared with the series reported. Different diagnostic criteria applied and the fact that our patients come from the general population and not from specialized services, could account for these results. Accordingly, in our community, routinely testing the autonomic nervous system from the early stages of diabetes would not be justified. P15.4 Microneurographic evaluation of sympathetic activity in small fiber neuropathy M.P. Giannoccaro1 , V. Donadio1 , V. Di Stasi1 , F. Pizza1 , P. Cortelli1 , A. Baruzzi1 , P. Montagna1 , R. Liguori1 1 Department of Neurological Science, University of Bologna, Bologna, Italy Introduction: Small fiber neuropathy (SFN) may involve somatic and autonomic fibers. Assessment of somatic epidermal nerve fiber density (ENFs) is considered the gold standard test in the diagnosis of SFN. By contrast, autonomic involvement is more difficult to ascertain. Objective: We investigate peripheral sympathetic outflow by microneurography in patients with selective SFN of different origin with and without autonomic symptoms to ascertain the ability of microneurography and the corresponding skin organ effector responses (sympathetic skin activity-SSR and skin vasomotor reflex-SVR) to disclose autonomic involvement. Methods: We studied 59 patients with SFN because of reduced leg ENFs and normal conduction studies. Thirty patients reported only burning paresthesia (somatic SFN) whereas twenty-nine patients complained of additional autonomic dysfunctions (autonomic SFN). They underwent to microneurography from peroneal nerve with the recording of muscle sympathetic nerve activity (MSNA), skin sympathetic nerve activity (SSNA) and the corresponding SSR and SVR in the same innervation field. Thirty age and sex-matched healthy subjects served as controls. Results: Autonomic SFN patients mainly complained of loss of sweating. They showed a significant absence of indirect (SSR and SVR) and direct (MSNA and SSNA) sympathetic tests compared to somatic SFN patients and controls. SSNA, SSR and SVR were more often absent than MSNA. In addition, SSR and SVR were absent in all patients with no recordable SSNA but no significant relationship was found with MSNA recording. Conclusions: SSR and SVR, simple indirect tests of sympathetic activity, could help to disclose autonomic involvement in SFN with a good sensitivity as microneurography which additionally contribute to express the extension of autonomic involvement. Our data pointed out that the skin sympathetic branch is more often involved than the muscle sympathetic branch in SFN. P15.5 Familial primary focal hyperhidrosis: neurophysiological assessment of cardiovascular autonomic function F. Del Sorbo1 , G. De Joanna2 , G. Lauria3 , A. Albanese4 Neurologia I, IRCCS Istituto Neurologico Carlo Besta, Milan, Italy, 2 Dipartimento di Neurologia, Azienda Ospedaliera Cardarelli, Naples, a Malattie Neuromuscolari, IRCCS Istituto Neurologico Carlo Italy, 3 Unit` Besta, Milan, Italy, 4 Neurologia I IRCCS Istituto Neurologico Carlo Besta, Universit` a Cattolica del Sacro Cuore, Milan, Italy

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Introduction: Cardiovascular dysautonomia has been recently identified in sporadic primary focal hyperhidrosis (PFH), but no data are available on this topic in familial PFH. Objective: To investigate cardiovascular autonomic function of a large Italian family affected by PFH with autosomal dominant transmission. Methods: All available family members underwent full assessment of autonomic symptoms and cardiovascular autonomic reflex examination. The proband had electromyography (EMG), nerve conduction study (NCS) and punch skin biopsies. Results: We investigated 9 family members, of whom 6 were clinically diagnosed with PFH. Hyperhidrosis was characterized by early onset and bilateral involvement of multiple areas. Cardiovascular autonomic tests were abnormal in all affected family members and in one unaffected