OBJECTIVE: Early differentiation between Parkinson\'s disease (PD) and Multiple system atrophy (MSA), particularly the parkinsonian subtypes (MSA-P), is challenging due to similar clinical symptoms. We aimed to evaluate Sympathetic skin response (SSR) and Cutaneous silent period (CSP) parameters in patients with MSA-P and PD to identify possible biomarkers that could distinguish the two groups of patients in early stage.
METHODS: 22 individuals with early-stage MSA-P, 29 with early-stage PD, and 28 healthy controls were recruited from Guangdong Provincial People\'s Hospital. Demographic data was collected for all participants. Their SSR and CSP were evaluated using clinical electromyography equipment. Data were compared between different groups. The diagnostic accuracy of SSR and CSP parameters was calculated using the ROC curve. Logistic regression was used to produce an integration model to enhance diagnostic utility.
RESULTS: Foot amplitude, CSP end latency and duration distinguished MSA-P from PD with the area under the curve (AUC) 0.770, 0.806, and 0.776, respectively. Foot and hand SSR amplitude distinguished PD from HC with the AUC 0.871 and 0.768, respectively. Foot SSR amplitude, hand SSR amplitude, and CSP end latency distinguished MSA-P from HC with the AUC 0.964, 0.872, and 0.812, respectively. The combination of SSR and CSP parameters differentiation between MSA-P and PD, PD and HC with the AUC 0.829 and 0.879, respectively.
CONCLUSIONS: Analysis of SSR and CSP parameters showed excellent diagnostic accuracy in discriminating patients with early-stage MSA-P from HC and good diagnostic accuracy in discriminating patients with MSA-P from PD with early stages.

BACKGROUND: This study aimed to explore autonomic nervous system involvement in amyotrophic lateral sclerosis (ALS) patients by evaluating sympathetic skin response (SSR).
METHODS: The study included 35 sporadic (ALS) patients (cases), and 35 healthy age and sex-matched participants (controls) aged <60 years. SSR was recorded in the electrophysiology lab of the Neurology Department of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh. Patients with diseases associated with peripheral or autonomic neuropathy were excluded. Prolonged latency (delayed SSR) or an absent response was considered abnormal SSR.
RESULTS: SSR was found to be abnormal in 17 (48.6 %) ALS cases, with an absent response in the upper limbs of six cases (17.1%). Abnormal SSR was more prevalent in the lower limbs, with 33 (94.3%) and 20 (57.1%) cases having a delayed or absent response, respectively. In comparison, SSR was normal in all control participants (P-value <0.05). Abnormal SSR was significantly more common in the lower limbs of ALS cases with bulbar palsy than those without bulbar palsy (P-value=0.04). There was no association of SSR with disease severity and duration.
CONCLUSIONS: ALS is significantly associated with abnormal SSR, indicating autonomic nervous system involvement. There could also be an association between bulbar palsy and abnormal SSR among ALS patients. Further studies should be carried out to determine the association of abnormal SSR with disease severity, duration, and type.

BACKGROUND: There is a limited number of studies assessing the alterations in nerve function impairment (NFI) in leprosy over an extended period of time. To the best of our knowledge, no published study has evaluated neurological state longitudinally during treatment utilizing a combination of clinical, functional (activity limitation), electrophysiological, and patient-reported quality of life (QOL) outcomes.
METHODS: This prospective, observational study included leprosy patients of all spectra. Over 1 year of treatment, cutaneous and neurological examinations were done in addition to a nerve conduction study (NCS) and sympathetic skin response (SSR) assessment. QOL and activity limitation assessments using the World Health Organization Quality of Life brief version (WHOQOL-BREF) and Screening of Activity Limitation and Safety Awareness scale (SALSA), respectively, were also performed.
RESULTS: Out of 63 leprosy patients, loss of sensation was noted in 43 (68.2%) at baseline. At the completion of treatment, proportionate change revealed no change in 18 (28.5%), restored function in 9 (14.2%), improved status in 34 (53.9%), and deteriorated NFI in only 2 (3.1%) cases. The association between NCS-SSR abnormalities was significant for a longer duration of disease at presentation (P = 0.04), in multibacillary cases [OR 9.12 (95% CI, 1.22-67.93)], in those in reaction [OR 3.56 (95% CI, 0.62-20.36)] and in those aged over 40 [OR 1.93 (95% CI, 0.28-13.41)]. There was an improvement in WHOQOL-BREF and SALSA scores at release from treatment (P = 0.005 and P = 0.01, respectively).
CONCLUSIONS: The majority of leprosy patients on treatment show improvement in NFI at the completion of therapy. However, change is influenced by critical factors such as bacillary load, disease duration, age, and the presence of reaction(s).

BACKGROUND: Parkinson\'s disease (PD), and other parkinsonian syndromes are known to cause striatonigral dopaminergic system dysfunction and autonomic disturbances, including the vasomotor and sudomotor nervous systems. The detection of 123I-FP-CIT SPECT (DaT scan) imaging and autonomic dysfunction helps differentiate PD from multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). The sympathetic skin response (SSR) is a simple, non-invasive electrophysiological test that assesses the sympathetic sudomotor nervous system. It is reported that the SSR is impaired in patients with PD, MSA, and PSP.
OBJECTIVE: To study the relationship between SSR, 123I-metaiodobenzylguanidine (MIBG) cardiac scintigraphy and DaT scan imaging parameters in patients with PD, MSA, and PSP.
METHODS: The study included 62, 25, and 19 patients with PD, MSA, and PSP, respectively. The SSR, MIBG cardiac scintigraphy, and DaT scan imaging were examined. The amplitude and latency of the SSR were measured in all limbs and were compared with the results of MIBG cardiac scintigraphy and DAT scan imaging.
RESULTS: The SSR amplitudes were lower than reported normal subjects\' reference values in PD, MSA, and PSP. The SSR amplitude only correlated with MIBG cardiac scintigraphy and DaT scan imaging parameters in PD. Multiple regression analyses also showed a significant relationship between the amplitudes of SSR and DaT scan imaging in PD.
CONCLUSIONS: Unlike MSA, and PSP, the sudomotor nervous system is parallelly involved with cardiac sympathetic and central dopaminergic dysfunction from the early stage of PD.

UNASSIGNED: Boron effects on reproduction and growth have been extensively studied in animals. Electrodermal activity (EDA) reflects the activity of eccrine sweat glands stimulated by the release of acetylcholine from sympathetic nerves.
UNASSIGNED: In the presen study, it was aimed to examine the effect of boron, which was turned into cream, on sweat glands.
UNASSIGNED: A cream form mixed with thyme oil was prepared for EDA recording. Our groups were formed as EDA recording gel (Group 1), cream with thyme oil (Group 2), cream containing 10% boron (Group 3) and cream containing 30% boron (Group 4). In each group, 3 months old, 10 male rats were used, and creams were applied to the soles of the hind extremities of the rats, EDA was recorded from this region after half an hour, and skin conductivity levels (SCL) were recorded as tonic (at rest) and phasic (with auditory sound stimulation).
UNASSIGNED: EDA results recorded in the morning were analysed with tonic and phasic recordings. In the morning SCL measurements, tonic SCL value of Group 4 was higher than the other groups (P < 0.001). Although the phasic SCL value was measured, it was significantly higher in Group 4 than in all groups (P < 0.0s).
UNASSIGNED: EDA measurements showed that boron increased sweat gland activity by increasing sympathetic nerve activity.

OBJECTIVE: To evaluate the sensitivity of sympathetic skin response (SSR) and compare it with scintigraphy in patients with complex regional pain syndrome diagnosed according to the Budapest criteria.
METHODS: Twenty-two patients with complex regional pain syndrome who attended the Rehabilitation and Physical Medicine Department between January-2018 and May-2022 have been prospectively evaluated. The scintigraphy was considered positive if in the 1st-2nd phase slight asymmetric and diffuse uptake was observed, or when in the 3rd phase marked periarticular radioisotope uptake was observed. SSR was abnormal if: a) no response after 20 stimuli; b) lack of habituation with permanence of the stimuli greater than 67.2%.
RESULTS: Age 55.4±8.57 years. Complex regional pain syndrome was more frequent in women (90.9%), more common in upper limbs (68.2%) than lower limbs (31.8%). In SSR, we have observed normal response (<67.2%) in 2 patients (11.1%), lack of SSR in 2 patients (11.1%) and lack of habituation (>67.2%) in 14 patients (77.8%). In total, 16 patients presented abnormal or absent responses (88.8%). The diagnostic sensitivity of scintigraphy is similar to that of SSR (89.5% vs 88.8%), with no statistical difference (P=.6721).
CONCLUSIONS: Scintigraphy has shown similar sensitivity to SSR, although the simplicity, security, low cost, non-ionizing and non-invasiveness of the latter technique suggest that it could be more cost-effective. The lack of habituation and the absence of response could identify response patterns and localize the involvement in the afferent, central, efferent or post-ganglionic pathways.

BACKGROUND: Diabetic peripheral neuropathy (DPN) and diabetic nephropathy (DN) are common complications of type 2 diabetes mellitus (T2DM). Although nerve conduction studies (NCS) and sympathetic skin response (SSR) can detect DPN, the more sensitive method for early diagnosis remains unclear. Furthermore, whether DPN can be used as a predictor for diabetic nephropathy needs clarification.
METHODS: We evaluated nerve conduction studies, sympathetic skin response, and the diabetic nephropathy indicator microalbuminuria (MAU) in 192 patients with type 2 diabetes mellitus and 50 healthy controls.
RESULTS: Patients with type 2 diabetes mellitus showed a lower sensory nerve conduction velocity (SCV), sensory active nerve potential (SNAP), motor nerve conduction velocity (MCV), and compound motor action potential (CMAP) than the controls on NCS. Abnormal rates for nerve conduction studies and sympathetic skin response were 75.0% and 83.3%, respectively, in patients with type 2 diabetes mellitus. Interestingly, 54.2% of patients with normal nerve conduction studies had an abnormal sympathetic skin response. Moreover, we found a positive correlation between sympathetic skin response and microalbuminuria for the first time. The abnormal rate of microalbuminuria was 53.8%, lower than that of abnormal nerve conduction studies or sympathetic skin response patients.
CONCLUSIONS: Sympathetic skin response is a more sensitive method than nerve conduction studies for the early diagnosis of diabetic peripheral neuropathy. Abnormal sympathetic skin response might serve as an indicator for early diabetic nephropathy. Additionally, diabetic peripheral neuropathy may occur earlier than diabetic nephropathy in the development of type 2 diabetes mellitus.

The morbidity of type 1 diabetes mellitus (T1DM) in children is increasing and diabetic peripheral neuropathy (DPN) is one of the main microvascular complications of T1DM. The aim of this study was to explore sympathetic skin response (SSR) characteristics in children with T1DM and analyze the value of early diagnosis and follow-up in T1DM complicated with DPN.
Our prospective study enrolling 85 participants diagnosed with T1DM and 30 healthy controls (HCs) in the Children\'s Hospital of Hebei Province from 2017 to 2020. Compared the outcomes of SSR and nerve conduction study (NCS) in T1DM, and evaluated the variations in SSR and NCS of different durations, as well as changes after six months of therapy.
SSR latency of T1DM group showed statistical difference as compared to HCs (p < 0.05). The SSR test was more sensitive than the NCS test in the early diagnosis of T1DM with DPN (p < 0.05). The abnormal rates of SSR and NCS in long duration of disease were higher than those in short duration of disease (p < 0.05). Among 65 participants with diabetic neuropathy, the onset latencies of SSR were shortened and the NCS were improved after treatment (p < 0.05).
SSR could provide the accurate early diagnosis and follow-up of pediatric diabetic peripheral neuropathy.

OBJECTIVE: To explore the value of sympathetic skin response (SSR) in the early diagnosis and prognostic evaluation of Guillain-Barre syndrome (GBS) in children.
METHODS: A retrospective analysis was conducted on the clinical data of 25 children with GBS who were diagnosed from October 2018 to November 2022, and 30 children who were diagnosed with Tourette\'s syndrome during the same period were selected as the control group. The characteristics of SSR were compared between the two groups, and the association of SSR with autonomic dysfunction (AD), disease severity, and prognosis was analyzed.
RESULTS: The GBS group had a significantly higher abnormal rate of SSR than the control group during the acute phase (P<0.001). SSR combined with early nerve conduction (within 2 weeks after onset) had a sensitivity of 84%, a specificity of 100%, and an accuracy of 93% in the diagnosis of GBS. There were no significant differences in the proportion of AD cases, as well as the Hughes scores during the disease peak, between the abnormal and normal SSR groups (P>0.05). All 7 children with poor short-term prognosis (at 1 month after onset) had abnormal SSR.
CONCLUSIONS: SSR can be used for the early diagnosis of GBS and the monitoring of treatment response in children.
目的: 探讨交感皮肤反应（sympathetic skin response, SSR）对儿童吉兰-巴雷综合征（Guillain-Barré syndrome, GBS）早期诊断及预后评估的价值。方法: 回顾性收集2018年10月—2022年11月收治的25例GBS患儿的临床资料，选取同期诊断为抽动障碍的30例患儿作为对照组，比较两组患儿间SSR的特点，并分析SSR与自主神经功能障碍（autonomic dysfunction, AD）、疾病严重程度及预后的关系。结果: GBS组患儿急性期SSR异常率高于对照组（P<0.001）。联合SSR和神经传导早期（发病2周内）诊断GBS的灵敏度、特异度和准确度分别为84％、100％和93％。SSR异常患儿AD比例及疾病高峰时Hughes评分与SSR正常患儿比较差异均无统计学意义（P>0.05）。短期（发病1个月）预后不良患儿SSR测定全部（7/7）异常。结论: SSR可以用于早期辅助诊断儿童GBS和监测疾病治疗情况。.

Modulated autonomic responses to noxious stimulation have been reported in experimental and clinical pain. These effects are likely mediated by nociceptive sensitization, but may also, more simply reflect increased stimulus-associated arousal. To disentangle between sensitization- and arousal-mediated effects on autonomic responses to noxious input, we recorded sympathetic skin responses (SSRs) in response to 10 pinprick and heat stimuli before (PRE) and after (POST) an experimental heat pain model to induce secondary hyperalgesia (EXP) and a control model (CTRL) in 20 healthy females. Pinprick and heat stimuli were individually adapted for pain perception (4/10) across all assessments. Heart rate, heart rate variability, and skin conductance level (SCL) were assessed before, during, and after the experimental heat pain model. Both pinprick- and heat-induced SSRs habituated from PRE to POST in CTRL, but not EXP (P = 0.033). Background SCL (during stimuli application) was heightened in EXP compared with CTRL condition during pinprick and heat stimuli (P = 0.009). Our findings indicate that enhanced SSRs after an experimental pain model are neither fully related to subjective pain, as SSRs dissociated from perceptual responses, nor to nociceptive sensitization, as SSRs were enhanced for both modalities. Our findings can, however, be explained by priming of the autonomic nervous system during the experimental pain model, which makes the autonomic nervous system more susceptible to noxious input. Taken together, autonomic readouts have the potential to objectively assess not only nociceptive sensitization but also priming of the autonomic nervous system, which may be involved in the generation of distinct clinical pain phenotypes.NEW & NOTEWORTHY The facilitation of pain-induced sympathetic skin responses observed after experimentally induced central sensitization is unspecific to the stimulation modality and thereby unlikely solely driven by nociceptive sensitization. In addition, these enhanced pain-induced autonomic responses are also not related to higher stimulus-associated arousal, but rather a general priming of the autonomic nervous system. Hence, autonomic readouts may be able to detect generalized hyperexcitability in chronic pain, beyond the nociceptive system, which may contribute to clinical pain phenotypes.