A study on the effect of duration of Type 2 diabetes mellitus on nerve conduction velocity and amplitude

Background: Diabetic peripheral neuropathy (DPN) is a frequent complication of diabetes mellitus and a common cause of foot ulcers and non-traumatic lower limb amputations. The duration of diabetes increases the likelihood of developing DPN, and many individuals have subclinical neuropathy without any symptoms. Electrophysiological assessment of nerve conduction is a simple, objective, and easily reproducible technique to detect DPN and to assess its progression with diabetes duration. Aims and Objectives: This study was done to determine the effect of Type 2 diabetes duration on nerve conduction velocity and amplitude. Materials and Methods: A total of 40 patients with Type 2 diabetes were chosen for the study. The subjects were divided into two groups: Group 1 with diabetes duration <7 years, and Group 2 with diabetes duration more than 7 years. The nerve conduction study is done using RMS EMG Medicare systems in the right median nerve (motor component) in both groups of subjects. Results: There was a significant reduction (P = 0.05) in both nerve conduction velocity (48.53 ± 4.95 m/s) and amplitude (3.33 ± 1.15 mv) in diabetic patients with diabetes duration >7 years when compared with nerve conduction velocity (51.69 ± 4.64 m/s) and amplitude (4.05 ± 0.92 mv) in diabetic patients with diabetes duration <7 years. Conclusion: With increase in duration of diabetes, there is a reduction in a nerve conduction velocity and amplitude.

Nerve Conduction Study Findings in Ulnar-Median Nerve Intercommunications in the Upper Limb: A Short Review

Intercommunications between ulnar and median nerves in the forearm and hand are a commonly encountered phenomenon. Clinicians should be aware of these communications for better diagnosis and management of the patient, as the clinical presentation can often be misleading. Surgeons should be aware of these anastomoses so as to prevent any iatrogenic injury during the course of treatment. Furthermore, these intercommunications can distort the findings on nerve conduction studies, leading to misinterpretation and misdiagnosis. In the forearm region, there are two prominent median-ulnar anastomoses, namely, Martin–Gruber anastomosis (MGA) and reverse MGA (Marinacci anastomosis). Similarly, in the palm too, there are two major anastomoses, namely, Riche–Cannieu anastomosis and Berrittini anastomosis. Here, in this review, we would like to emphasize on electrophysiological findings that can be observed in the presence of such anastomoses.

Nerve Conduction Study In Different Clinical Grades Of Diabetic Foot

Background:Diabetic neuropathy is one of the commonest late complications of diabetes. Diabetic neuropathy can be either peripheral or autonomic. Nerve conduction study (NCS) is the recording and measurement of the compound nerve and muscle action potentials elicited in response to an electrical stimulus. Currently, the principal uses of NCV(Nerve Conduction velocity) study are to evaluate paresthesias (numbness, tingling, burning) and /or weakness of arms or legs.Methods:All patients diagnosed as diabetic foot were sent for Nerve Conduction Study after obtaining their written informed consent. Three nerves were studied; two motor nerves, Common peroneal and Tibial nerves, and one purely sensory nerve, Sural nerve.Results:Mixed type neuropathy with bilateral lower limb involvement was the most common type encountered.Interpretation and Conclusion:Mixed type of neuropathy was the most common in my study with respect to sensory and motor types of neuropathy; and also axonal and demyelinating types of neuropathy.Number of patients with bilateral neuropathy detected by NCVstudy in my study is more than that detected clinically and the difference is significant by applying the test of significance. Hence, NCVis a better study to detect nerve conduction abnormalities than clinical examination in diabetic foot

Study on Prognostic Value of Electrophysiological Tests in Bell’s Palsy

Introduction: Bell’s palsy is an idiopathic peripheral disease of the seventh cranial nerve. More than 70% of patients attaincomplete clinical recovery, with no noticeable residua. Electrophysiological tests may offer valuable information in defining theseverity of nerve injury and a possible subsequent dysfunction.Aim: This study aims to assess the prognostic value of electrophysiological tests in the management of Bell’s palsy.Materials and Methods: All the patients with Bell’s palsy and without clinical evidence of other cranial nerve damage or centralnervous system diseases were included in the study. Nerve conduction study was performed on the 14th day or on the firstvisit of the patient to the hospital.Results: In 101 patients, majority of patients come under Grade IV (43.6%) and next comes Grade V (31.7%). Eighty-twopatients (81.2%) had normal latency, among these, 73 cases recovered within 6 months. Of 17 who had prolonged latency,seven patients recovered fully.Conclusions: Electrophysiological studies can predict the duration of the clinical recovery and the outcome of the illness. Theamplitude ratio of compound muscle action potential is the most reliable parameter in assessing the prognosis.

Chronic inflammatory demyelinating polyneuropathy presenting as Guillain–Barre syndrome: A case presentation

Guillain–Barre syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are immune-related neuropathies and differentiated mainly by disease course. GBS is characterized by a monophasic course, with a clinical nadir within 4 weeks of symptom onset, whereas CIDP typically demonstrates a slowly progressive course with gradual worsening over more than an 8-week period. Both may share common features such as demyelinating polyneuropathy, raised protein in cerebrospinal fluid, and conduction delay or block in nerve conduction study. Here, we present a case who was diagnosed and managed as GBS based on history, clinical presentation, and electrodiagnostic criteria on initial visit. Later on, we revised our diagnosis to acute-CIDP when the patient deteriorated after 8 weeks. This subset of the patient (up to 16% of CIDP) may initially present as GBS. Distinguishing between GBS and CIDP is crucial as prognosis and treatment differ.

Mortality Outcome in Patients of Guillian Barre Syndrome. A single Center Study

Introduction: The Guillian Barre syndrome (GBS) is characterised by acute areflexic paralysis with albumincytological dissociation. Study was undertaken to analyze the electrophysiological studies, clinical profile and outcome of GBS at our institute. Material and Methods: This study was a hospital based descriptive and prospective study was conducted on patients admitted in the Medical intensive care unit. Patients with age more than 18 years, irrespective of their sex, diagnosed as GBS, fulfilling the criteria as modified by Asbury were included in the current study. Association between qualitative variables was assessed by Chi-Square test. Quantitative data was represented using mean ± SD, median. Results: Out of 50 enrolled, 21 patients belonged to age 21 to 40. 33 pts were male and 17 pts were female, 7 patients expired. Two peak of occurrence of GBS was found in age one in age group 21 to 41years and another in age more than 51 years.13 patients had history of antecedent infection. 35 patients had albumin-cytological dissociation. As per the results of nerve conduction study, patients were categorized in the following 3 groups AMAN-24, AIDP-14 and ASMAN-12. Conclusions: The independent predictors for the need of mechanical ventilation were history of breathlessness on admission, SBC of equal to or less than 10, upper or lower limb power of less than or equal to 2 (P valve <0.01). The predictors of poor outcome were presence of sepsis, need for mechanical ventilation, VAP, SBC of < 10 and lower limb power < 2.

A Study On Carboplatin –PACLITAXEL Induced Peripheral Neuropathy In Cancer Patients

Background: Peripheral neuropathy is a common treatment related adverse effect and affects long term quality of life. AIM: To study the Carboplatin–Paclitaxel induced peripheral neuropathy in patients with lung or ovarian cancer. Methods: The study was carried out in the Department of Oncology, Government Rajaji Hospital, Madurai, after obtaining clearance from Institutional ethical committee, Government Rajaji Hospital, Madurai.Thirty newly diagnosed patients suffering from Lung or ovarian cancer attending Oncology department were selected. After satisfying inclusion and exclusion criteria,Patient received Injection Carboplatin AUC 6 and Injection Paclitaxel 175mg/m2 . Nerve conduction study was done to assess the peripheral neuropathy. It was done before starting the chemotherapy.Patients with grade 0 neuropathy were included for the study.Nerve conduction study was repeated after each cycle. The time taken to develop peripheral neuropathy was assessed using Cancer Institute – Common Toxicity Criteria version 3.0. The data were analyzed with SPSS statistical software package (Version 16.0 SPSS Inc., Chicago, USA ). Results: There is a statistically significant reduction in sensory nerve (sural) amplitude (SNAP) and latency (p<0.05) indicating significant axonal damage. The time taken to develop peripheral neuropathy was 4 Cycles with Grade 2/4. Conclusions: In this present study , the neurotoxicity induced by Carboplatin–Paclitaxel in patients with lung or ovarian carcinoma was observed. More effective dosing– schedules of treatment decreases the incidence of long lasting peripheral neurotoxicity thus providing better results withlonger survival rate and less disability.

A study on cisplatin -paclitaxel induced peripheral neuropathy in cancer patients

Background: Chemotherapy induced peripheral neuropathy is a significant disability after the treatment of large number of cancers and they have an impact on quality of life. The aim of the present endeavour was to study the cisplatin-paclitaxel induced peripheral neuropathy in patients with lung or ovarian cancerMethods: The study was carried out in the Department of Oncology, Government Rajaji Hospital, Madurai, after obtaining clearance from Institutional ethical committee, Government Rajaji Hospital, Madurai. Thirty newly diagnosed patients suffering from Lung or ovarian cancer attending Oncology department were selected. After satisfying inclusion and exclusion criteria. Patient received injection cisplatin 60 mg/m2 and injection paclitaxel 175 mg/m2. Nerve conduction study was done to assess the peripheral neuropathy. It was done before starting the chemotherapy. Patients with grade 0 neuropathy were included for the study. Nerve conduction study was repeated after each cycle. The time taken to develop peripheral neuropathy was assessed using Cancer Institute - Common Toxicity Criteria version 3.0. The data were analyzed with SPSS statistical software package (Version 16.0 SPSS Inc., Chicago, USA ).Results: There is a statistically significant reduction in sensory nerve (sural) amplitude (SNAP) and latency (p <0.05) indicating significant axonal damage. The time taken to develop peripheral neuropathy was 3 cycles with grade 3/4.Conclusions: In this present study, the neurotoxicity induced by cisplatin-paclitaxel in patients with lung or ovarian carcinoma was observed, so that early intervention can prevent the permanent neurotoxicity.

Motor nerve conduction study parameters in healthy individuals: effect of limb dominance

Background: Nerve conduction study (NCS) is useful for evaluation of nerve, muscle, and/or neuromuscular function. Neurophysiologist interprets NCS with consideration of various anthropometric and technical parameters viz. age, gender, height, temperature etc. apart from the underlying pathology. Fewer studies have reported the effect of limb dominance on NCS. Moreover, the findings are controversial. Therefore, author aimed to investigate the effect of limb dominance on motor nerve conduction study parameters.Methods: This cross-sectional comparative study included sixty healthy individuals (44 right and 16 left handed) of either sex with age 18 to 30 years. The NCS parameters of median and ulnar nerves were assessed by stimulating it and recording from the muscle and skin overlying the nerve respectively using Digital Nihon Kohden machine. The obtained data were analyzed using independent sample t-test.Results: Right ulnar nerve onset latency was significantly longer in left-handed individuals (1.85±0.508 ms vs 1.62±0.195 ms, p=0.012). The left ulnar nerve F wave minimum latency (25.88±0.74 ms vs 24.46±2.64 ms, p=0.002) was significantly longer in left-handed individuals. Likewise, right ulnar nerve distal latency (2.45±0.76 ms vs 2.14±0.39 ms, p=0.044), and right ulnar nerve F wave minimum (25.9±1.21 ms vs 24.85 ms±1.74, p=0.030) were significantly high in left-handed individuals.Conclusions: NCS parameters in terms of latencies were longer in left-handed individuals. Therefore, limb dominance seems to be an important factor one should pay attention during bilateral comparison of obtained data in neurophysiological reporting of referred cases.

Could Ultrasound-Guided Stimulation of Sural Nerve Affect Nerve Conduction Study?

OBJECTIVE: To determine anatomical variation of the sural nerve (SN) by ultrasonography (US) and compare sensory nerve action potential (SNAP) of the SN obtained by a control method to that obtained with adjusted method using US. METHODS: Eighty legs of 40 healthy volunteers were enrolled. The location and formation of SN were investigated through US. Two methods of nerve conduction study (NCS) were then performed. In the control method, the cathode was placed 14 cm proximal to the lateral malleolus and the greatest SNAP amplitude was obtained by moving the cathode medially or laterally from just lateral to the calf-mid line. In adjusted NCS, the exact SN union site was stimulated in type 1. In other SN types, the stimulation was done directly over the nerve and the distance from the lateral malleolus was set to be 14 cm. RESULTS: It was found that 73.8% of the SNs were type 1, 22.5% were direct continuation of MSCN (type 2), and 3.8% were MSCN and LSCN without communicating (type 4). However, type 3 was not found. The union point in type 1 SN was 12.6±2.5 cm proximal to the lateral malleolus and 1.4±0.7 cm lateral to the calf-midline. After stimulation adjustment, SNAP amplitude in type 1 SN was significantly increased (20.7±5.5 μV vs. 27.1±6.7 μV). CONCLUSION: Anatomical variation of SN and its location were verified by US. US provides additional information for conducting sural NCS and helps obtain more accurate results.

Interpretation of Electrodiagnostic Tests in Chronic Inflammatory Demyelinating Polyneuropathy: Classification Using Nerve Conduction Study / 대한신경근육질환학회지

Electrodiagnostic tests (EDX) is essential for the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP). EDX could provide information about demyelinating pathology in the peripheral nerves. According to phenotypes, CIDP could be classified several phenotypes, which has different clinical manifestations, EDX could present a different distribution pattern of demyelinating lesions. In addition, EDX could be useful markers for predicting treatment response of prognosis of CIDP.

Clinical and electrophysiological correlation of peripheral neuropathy in newly diagnosed type 2 diabetes mellitus

Background: The study was undertaken to evaluate the prevalence of peripheral neuropathy in newly diagnosed type2 Diabetes mellitus (DM) by clinical examination and nerve conduction study (NCS), and to correlate them with risk factors.Methods: Eighty newly detected cases of type2DM of age ≥18 years attending Endocrinology Department of Gauhati Medical College and Hospital, Assam, India were evaluated. Grading of symptoms and signs was done using the Neuropathy Symptoms Score (NSS) and Neuropathy Disability Score (NDS) respectively followed by NCS. Neuropathy was diagnosed based on abnormal NSS, NDS or NCS.Results: Prevalence of peripheral neuropathy was 68.75 % based on abnormal NCS/NDS/NCS. The most common symptom was presence of paraesthesia in 70.9%, followed by weakness in lower limbs in 16.36%. The most common sign was impairment of vibration perception in 76.3%, followed by absent ankle reflex in 56.36%. Abnormal NCS finding was seen in 55% of patients with neuropathy. Of all the patients with neuropathy, only 2.5% had subclinical neuropathy that is abnormal NCS finding in absence of sign and symptoms. Peripheral neuropathy had significant association with age at diagnosis, presence of hypertension, fasting plasma glucose(FPG), HbA1c, serum creatinine and estimated glomerular filtration rate(eGFR) (p<0.05). On multiple linear regression analysis, only age at diagnosis and FPG were independently associated with neuropathy (p<0.05).Conclusions: Patients with type 2DM have a high prevalence of peripheral neuropathy at diagnosis and very few of them harbour subclinical neuropathy. This study has shown that clinical examination still remains the main tool for detection of neuropathy.

Comparative study of detection of diabetic neuropathy by clinical and nerve conduction study in type 2 diabetes mellitus patients

Background: Diabetes mellitus is known for its complications such as retinopathy, neuropathy and nephropathy. Diabetic neuropathy is one of the devastating complication associated with diabetes mellitus. The objective of this study was to detect sensory motor neuropathy in type 2 Diabetes mellitus by clinical examination and nerve conduction study and to correlate clinical features of peripheral neuropathy with nerve conduction study in Type 2 Diabetes mellitus.Methods: This study was undertaken to study types of neuropathy in type 2 diabetes and to correlate clinical features of peripheral neuropathy with nerve conduction study in type 2 diabetes mellitus.100 patients with diabetes whose onset of diabetes mellitus after age of 30 years and duration of diabetes 5 years or more visiting SGRDIMSR, Vallah, Amritsar were subjected to nerve conduction study to find out peripheral neuropathy.Results: Eight four percentage patients were found to have neuropathy on NCS whereas only 61% of patients were found to have neuropathy on clinical examination and detection rate with NCS was statistically significant (p <0.001) as compared to clinical examination.Conclusions: NCS helps in early detection of neuropathy and most common form of diabetic neuropathy is distal symmetrical polyneuropathy.

Neuropathy in cases of Hypothyroidism as Confirmed by Motor Nerve Conduction Studies: A Prospective Study in a Tertiary Care Hospital

Background: Thyroid hormone play important role in development of Central Nervous System and in myelination of neurons. Patients of hypothyroidism may suffer from peripheral nervous dysfunction. Aim of our study is to find out the neuropathy in hypothyroidism. Methods: This prospective study was conducted on 40 subjects, out of which n=20 were euthyroid control and n=20 were hypothyroid. The Study was performed in the Medicine department of Saraswathi Institute of Medical Sciences, Hapur in collaboration with the department of Physiology at G.S. Medical College, Hapur. MNCV and latency of Median, Ulnar, and Common Peroneal nerve of both upper and lower limb were done in patients of Hypothyroidism and in Control subjects. Results: Significant bilateral decrease is observed in the MNCV of the Median Nerve in Hypothyroid subjects as compared to the control subjects. Also, there  is Significant  bilateral  increase  in the  Motor Latency of the Median Nerve in Hypothyroid subjects as compared to the control subjects. Conclusion: Hypothyroidism cause significant decrease in MNCV of Median Nerve as well as increase in Motor latency in Median Nerve.

Comparing and analyzing the application value of F wave in the use of electrophysiological examination of diabetic peripheral neuropathy / 中国医师进修杂志

Objective To evaluate the application value of F wave by comparison with quantitative sensory testing(QST)and nerve conduction studies(NCS)in diabetes peripheral neuropathy (DPN). Methods Three hundred and fourteen diabetic patients with symptom of DPN were retrospectively analyzed, who were recruited and divided into four groups according the course of diabetes mellitus: ≤ 3 years group, 4-6 years group, 7-9 years group and >9 years group. The abnormal rates of QST, NCS and F wave were analyzed and compared. Results At earlier course of disease (≤ 3 years group, 4- 6 years group), the abnormal rate of QST [76.54%(62/81), 91.67% (88/96)]>F wave[(48.15%(39/81),64.58%(62/96)]>NCS[(32.10%(26/81),47.92%(46/96)], and there were significant differences(P<0.01).The abnormal rate of QST, F wave and NCS at 7-9 years group and>9 years group had no significant differences(P>0.05).The abnormal rate of QST in 4-6 years group[(91.67%(88/96)]was higher than that in≤3 years group[(76.54%(62/81)],and decreased in 7-9 years group and >9 years group. The abnormal rate of NCS was increased with course of disease, and the range was obviously between close together group. The abnormal rate of F wave was increased with course of disease,but in 4-6 years group the range was obvious and the range was slow down.At earlier course of disease (≤3 years group, 4-6 years group), the abnormal rate of only F wave significantly increased the abnormal rate of NCS + F wave from 30.86%(25/81), 44.79% (43/96)to 46.91%(38/81), 61.46%(59/96)respectively, but in 7-9 years group and>9 years group, the abnormal rate of only F wave increased the abnormal rate of NCS + F wave from 69.44%(50/72), 84.61%(55/65)to 72.22% (52/72),86.15%(56/65).Conclusions Although the abnormal rate of F wave is not as high as QST, it is still remarkable. Detection of F wave shows positive correlations with the course of disease, which can reflect the course of disease objectively and reliably.The added F wave detection can distinctly raise the abnormal rates on the base of NCS.

Low amplitude dorsal ulnar cutaneous nerve sensory nerve action potential from cross over innervation. Can nerve ultrasound help?

The ulnar dorsal aspect of the hand is predominantly innervated by the dorsal ulnar cutaneous nerve with variable input from the superficial radial cutaneous nerve. This cross innervation can cause difficulty in interpreting low amplitude sensory nerve action potential for the dorsal ulnar cutaneous nerve particularly when facing suspected ulnar neuropathyat the elbow. In three subjects with low dorsal ulnar cutaneous sensory nerve action potential amplitude due to cross over with the superficial radial nerve, we compared amplitude with nerve circumference and fascicular count as measured by ultrasound. Dorsal ulnar cutaneous nerve circumference was significantly smaller where there was low sensory nerve action potential amplitude and showed fewer fascicles. Nerve ultrasonography may be a useful additional test modality to determine if low dorsal ulnar cutaneous nerve amplitude is physiological.

Factors Associated with Peripheral Neuropathy in Type 2 Diabetes:Subclinical versus Confirmed Neuropathy / 华中科技大学学报（医学）（英德文版）

This study determined the prevalence of diabetic peripheral neuropathy (DPN) and subclinical DPN (sDPN) in patients with type 2 diabetes mellitus (T2DM) using nerve conduction study (NCS) as a diagnostic tool.We also investigated the factors associated with the development of sDPN and compared factors between the sDPN and confirmed DPN (cDPN).This cross-sectional study involved 240 T2DM patients who were successively admitted to the endocrinology wards of Wuhan Union Hospital over the period of January to December 2014.Data on the medical history,physical and laboratory examinations were collected.DPN was diagnosed using NCS.One-way ANOVA with least significant difference (LSD) analysis or chi-square tests was used to compare parameters among DNP-free,sDPN and cDPN patients.Independent factors associated with sDPN were determined using logistic regression.The results showed that 50.8％ of the participants had DPN,and among them,17.1％ had sDPN.sDPN showed significant independent associations with age,height,HbA1c,presence of atherosclerosis and diabetic retinopathy.Patients with DPN differed significantly from those without DPN with respect to age,duration of disease (DOD),HbA1c,presence of atherosclerosis,diabetic retinopathy,nephropathy and hypertension.Patients with cDPN,relative to those with sDPN,had significantly longer DOD and higher prevalence of peripheral artery disease (PAD) and coronary artery disease (CAD).Our study suggests that a significant number of T2DM patients are affected by sDPN,and the development of this condition is associated with advanced age,tall stature,poor glycaemic control,presence of diabetic retinopathy and atherosclerosis.On the other hand,patients with cDPN tend to have a longer DOD and are more likely to suffer from PAD and CAD.

Assessment of Diabetic Peripheral Neuropathy Using Current Perception Threshold / 계명의대학술지

The aim of this study was to compare the current perception threshold (CPT) with a nerve conduction study (NCS) to evaluate the usefulness of CPT in the diagnosis of diabetic Peripheral Neuropathy (DPN). CPT measurement is quantitative method for assessment of peripheral sensory nerve function using electrical impulse. Enrolled in this study were 142 patients with type 2 diabetes who underwent both CPT testing and NCS between January 2013 and April 2016. DPN was diagnosed by NCS. CPT was performed on the right index finger and great toe of each patient. Patients with burning, tingling sensation and with longer history of diabetes tended to have a higher prevalence of DPN. In all frequencies tested (2000, 250, 5 Hz), CPT values of the DPN group were higher than the normal group. After classification in either the normoesthesia or hypoesthesia group according to CPT, the DPN group had a significantly higher prevalence of hypoesthesia than normal group. The receiver operating characteristics curve analysis showed that CPT had a high area under curve value for predicting the presence of DPN. In conclusion, CPT measurement is clinically valuable in detecting nerve dysfunction in patients with type 2 diabetes.

Nerve Conduction Studies In Lower Limb Weakness.

Introduction: Nerve conduction studies (NCS) are an essential part of the work-up of peripheral neuropathies. NCS with EMG allows diagnostic classification, understanding and separation of different neuropathies. Symmetrical lower limb weakness of neurological origin often demands EDX study. Neuropathies may be mixed or motor or sensory. Further it may be either axonal or demyelinating. Aims and objectives: To assess nerve conduction studies in symmetrical lower limb weakness patients with peripheral neuropathies. To estimate prevalence of neuropathies in this cohort. Material methods: Forty cases and equal no of controls underwent NCV study. Tibial peroneal motor and sural sensory nerve conductions were done. Data was stored in excel sheet for analysis. Different NCV variables were compared between the groups. Unpaired t’test was used for comparison of variables. Level of significance was kept at p value <0.05. Results: It was observed that DML, CMAP/SNAP amplitude, and CV of study group were significantly different as compared to control group (p value <0.05). Neuropathy was present in 31 (77.5%) cases. 25 (80.65%) cases were axonal and 6 (19.35%) were demyelinating neuropathies. NCV was normal in 9 (22.5%) cases. Conclusion: NCV study proved an essential tool in diagnosis of neuropathies in lower limb weakness cases. Axonal neuropathies were more prevalent as compared to demyelinating one. Mixed neuropathies were more frequent than isolated motor or sensory neuropathies. Presence of conduction block suggests acquired demyelination.

Clinical and neurophysiological features of the hereditary neuropathy with liability to pressure palsy due to the 17p11. 2 deletion / Aspectos clínicos e neurofisiológicos de pacientes com a neuropatia hereditária com a susceptibilidade à pressão associada à deleção 17p11. 2

ABSTRACT The hereditary neuropathy with liability to pressure palsies (HNPP) is an autossomal dominant disorder manifesting recurrent mononeuropathies. Objective Evaluate its clinical and nerve conduction studies (NCS) characteristics, searching for diagnostic particularities. Method We reviewed the neurological manifestations of 39 and the NCS of 33 patients. Results Family history was absent in 16/39 (41%). The onset complaints were weakness in 24, pain in 6, sensory deficit in 5 and paresthesias in 4. Pain was seen in 3 other patients. The following neuropathy patterns were found: multiple mononeuropathy (26), mononeuropathy (7), chronic sensorimotor polyneuropathy (4), chronic sensory polyneuropathy (1) and unilateral brachial plexopathy (1). NCS showed a sensorimotor neuropathy with focal conduction slowing in 31, two had mononeuropathy and another brachial plexopathy. Conclusion HNPP presentation is variable and may include pain. The most frequent pattern is of an asymmetrical sensory and motor neuropathy with focal slowing at specific topographies on NCS.

RESUMO A neuropatia hereditária com susceptibilidade à pressão (HNPP) é uma doença autossômica dominante que manifesta mononeuropatias recorrentes. Objetivo Avaliar as características clínicas e os estudos da condução nervosa (ECN) procurando particularidades diagnósticas. Método Revisamos as características clínicas de 39 e os ECN de 33 pacientes. Resultados História familiar ausente em 16/39 (41%). As manifestações iniciais foram: fraqueza em 24, dor em 6, déficit sensitivo em 5 e parestesias em 4. Dor foi referida por outros 3 pacientes. Os seguintes padrões de neuropatia foram observados: mononeuropatia múltipla (26), mononeuropatia (6), polineuropatia sensitivo-motora (4), polineuropatia sensitiva (1) e plexopatia braquial unilateral (1). Os ECN mostraram uma neuropatia sensitivo-motora com redução focal da velocidade de condução em 31, dois tinham mononeuropatia e outro plexopatia braquial. Conclusão A apresentação da HNPP é variável e pode incluir dor. O padrão mais frequente é o de uma neuropatia sensitivo-motora assimétrica com alentecimentos focais da condução em topografias específicas nos ECN.