Sensory Axonal Neuropathy Research Articles

Chronic Inflammatory Demyelinating Polyneuropathy in Systemic Lupus Erythematosus: A Rare Entity

Background:Neurological manifestations in Systemic Lupus Erythematous (SLE) varies and commonly affects the Central Nervous System (CNS) rather than the peripheral nervous system. Neuropsychiatric or CNS manifestation can be as high as 24-54%, whereas the peripheral nervous system involvement is lower around 5-27%. Chronic Inflammatory Demyelinating Polyradiculopathy (CIDP) is one of the three commonest peripheral nervous system involvements in SLE patients and results with severe debilitating effects. However, it is rarely reported.Methods:A retrospective review of all SLE patients that were diagnosed with CIDP between 2000 and 2015 was done under follow up at our center that were diagnosed with CIDP between 2000 and 2015. We reviewed their medical records and analyzed their clinical presentation, investigations, treatment instituted, response to therapy and any neurological sequealae.Results:A total of 512 case notes were reviewed. Of these 4 patients presented with CIDP (3 females, 1 male) aged between 26 to 46 years old. Three presented with transverse myelitis and the other one with acute motor and sensory axonal neuropathy. All patients were treated with high dose corticosteroids, three patients received cyclophosphamide whilst the other patient was induced with mycophenolate mofetil. Complete recovery was seen in one patient, two had persistent but improving numbness and the other one had a residual weakness.Conclusion:Peripheral nervous system involvement in SLE can result in serious debilitating effects. Early diagnosis and treatment are crucial in limiting the neurological sequealae.

MITOCHONDRIAL DISEASES (Posters): P.188Novel POLG mutations and variable clinical phenotypes in 5 Chinese patients with mitochondrial diseases

POLG related mitochondrial disorders has rarely been reported in China. Here we report 5 unrelated Chinese patients (2 males and 3 females) with mitochondrial disease caused by POLG gene mutations. Two of them had a dominant family history and 3 were sporadic cases. The ages of onset were from 15 to 40 years old, with disease course ranging from 1 to 26 years. Clinically, 1 case were conformed with SANDO (sensory ataxic neuropathy, dysarthria and ophthalmoparesis) syndrome, 2 cases with autosomal dominant progressive external ophthalmoplegia (PEO), 1 case with autosomal recessive PEO, and 1 case with sensory axonal neuropathy and mental retardation. Laboratory examination revealed normal or mild elevation of serum creatine kinase level. Electromyography revealed myopathic or neurogenic pattern. Nerve conduction studies showed decreased amplitude of nerve action potential in 3 cases, with sensory nerve predominantly involved. Mitochondrial abnormality appeared in 4 patients who underwent muscle biopsies. Sural nerve biopsy revealed chronic axonal neuropathy in the patient with sensory axonal neuropathy and mental retardation. Genetic test revealed compound heterozygous POLG mutations in 3 sporadic patients and single heterozygous mutations in 2 dominant inherited patients. c.914G>A (p.S305N), c.924G>T (p.Q308H), c.1613A>T (p.E538V), c.1612G>T (p.E538*), c.1790 G>A (p.R597Q) and c.3002delG. were novel mutations. Novel mutations found in this study expanded the mutational spectrum of POLG.

Twinkle-Associated Mitochondrial DNA Depletion

BackgroundAutosomal recessive mutations in the nuclear Twinkle (C10orf2) gene cause a mitochondrial DNA depletion syndrome (MDS) characterized by early onset hepatoencephalopathy. MethodsWe report a severe, early onset encephalopathy and multisystem failure case caused by novel recessive Twinkle gene mutations. Patient clinical, laboratory, and pathological features are reported and Twinkle-associated MDS literature reviewed. ResultsTypical presentation includes symptom onset before age six months, failure to thrive, psychomotor regression, epileptic encephalopathy, sensory axonal neuropathy, cholestatic liver dysfunction, and occasionally, renal tubulopathy, movement disorders, and ophthalmoplegia. Death is typical before age four years. ConclusionsIn the differential diagnosis of early onset encephalopathy and multisystem failure, MDS should be considered.

Miller Fisher syndrome, Bickerstaff brainstem encephalitis and Guillain-Barr\xe9 syndrome overlap with persistent non-demyelinating conduction blocks: a case report

BackgroundMiller Fisher syndrome (MFS) and Bickerstaff’s Brainstem Encephalitis (BBE) share some clinical features and a common immunological profile characterized by anti-GQ1b antibodies. Some MFS patients overlap with Guillain-Barré syndrome (GBS) or BBE. We report a patient with MFS, BBE, and axonal GBS overlap in whom serial electrophysiological studies showed persistent motor conduction blocks (CBs).Case presentationA 61-year-old man acutely developed ophtalmoparesis, ataxia and areflexia suggesting MFS. Paresthesias, severe weakness, and drowsiness rapidly developed indicating an overlap with BBE and GBS. Preceding infection with Mycoplasma Pneumoniae and anti-GQ1b antibodies were detected. On day 4, nerve conduction study showed reduced or non-recordable compound muscle action potentials (CMAPs) and sensory nerve action potentials (SNAPs) without demyelinating features, indicating the electrodiagnosis of acute motor and sensory axonal neuropathy and suggesting a poor prognosis. Intravenous immunoglobulins (IVIg) were given but clinical status worsened to ophthalmoplegia, tetraplegia and coma needing mechanical ventilation. A second IVIg course was given and the patient was weaned off ventilation on day 41 and transferred to rehabilitation on day 57 with partial resolution of the ophthalmoplegia and limited recovery of muscle strength. Electrophysiology showed, after 10 weeks, greatly improved distal CMAP amplitudes suggesting the resolution of distal CBs while CBs in intermediate and proximal nerve segments emerged. CBs unusually persisted for four to 6 months without development of abnormal temporal dispersion. A third IVIg course was started on day 179 and the resolution of CBs mirrored the clinical improvement.ConclusionsGQ1b gangliosides are expressed in the nodal region of oculomotor nerves, muscle spindle afferents, peripheral nerves and possibly in the brainstem reticular formation. Anti-GQ1b antibodies may explain the complex symptomatology and the overlap between MFS, BBE, and GBS.CBs that persisted and recovered without the development of temporal dispersion suggest that weakness was due to a sustained, antibody-mediated, attack at the nodal region inducing a non-demyelinating conduction failure as expression of an acute onset, long lasting, nodopathy. Serial electrophysiological studies allowed not only to understand the underlying pathophysiology and formulate a more correct prognosis but also to guide the treatment.

When electrodiagnosis for tremor reveals a rare peripheral disease

Objectives Spinal and bulbar muscular atrophy (SBMA) (or Kennedy's disease) is a rare X-linked neurodegenerative disorder associated with limb and bulbo-facial paresis, sensory symptoms and tremor. Tremor usually precedes peripheral motor signs by a decade. It is supposed to result from several peripheral mechanisms [1] . Results Here we report a case of a 42 years-old patient who was addressed to the department for exploration of isolated bilateral upper limb tremor. Surface polymyographic examination revealed numerous spontaneous and short (7–12 ms) bursts at rest consistent with fasciculations and associated with a postural myoclonic tremor as well as with exaggerated physiological tremor of 8–10 Hz. Detailed clinical examination showed a generalized areflexia, cramps, mild paresis of upper limbs, gynecomastia and facial myokymia. Conventional electromyography (EMG) showed a chronic motor denervation in the muscles of the four limbs and the face with normal motor nerve conduction; however, fasciculations were not detected by needle EMG. In sensory nerves of four limbs, a homogeneous decrease of action potentials amplitudes was found consistent with axonal sensory neuropathy. Altogether, these findings were strongly suggestive of a SBMA. Genetic testing for CAG repeats in the androgen receptor gene is under investigation. As a reference, we show typical surface EMG recordings of upper limbs and neurophysiological characteristics of tremor of a patient with genetically documented SBMA (48 CAG triplets) at a more severe stage of the disease. Conclusion Spontaneous surface EMG activity compatible with fasciculations might be a valuable marker of a neuropathic tremor and potentially a revealing sign of SBMA.

Chemotherapy-Induced Peripheral Neuropathy in Long-term Survivors of Childhood Cancer

In light of the excellent long-term survival of childhood cancer patients, it is imperative to screen for factors affecting health, function, and quality of life in long-term survivors. To comprehensively assess chemotherapy-induced peripheral neuropathy in childhood cancer survivors to define disease burden and functional effect and to inform screening recommendations. In this cross-sectional observational study, cancer survivors who were treated with chemotherapy for extracranial malignancy before age 17 years were recruited consecutively between April 2015 and December 2016 from a single tertiary hospital-based comprehensive cancer survivorship clinic and compared with healthy age-matched controls. Investigators were blinded to the type of chemotherapy. A total of 169 patients met inclusion criteria, of whom 48 (28.4%) were unable to be contacted or declined participation. Chemotherapy agents known to be toxic to peripheral nerves. The clinical peripheral neurological assessment using the Total Neuropathy Score was compared between recipients of different neurotoxic chemotherapy agents and control participants and was correlated with neurophysiological, functional, and patient-reported outcome measures. Of the 121 childhood cancer survivors included in this study, 65 (53.7%) were male, and the cohort underwent neurotoxicity assessments at a median (range) age of 16 (7-47) years, a median (range) 8.5 (1.5-29) years after treatment completion. Vinca alkaloids and platinum compounds were the main neurotoxic agents. Clinical abnormalities consistent with peripheral neuropathy were common, seen in 53 of 100 participants (53.0%) treated with neurotoxic chemotherapy (mean Total Neuropathy Score increase, 2.1; 95% CI, 1.4-2.9; P < .001), and were associated with lower limb predominant sensory axonal neuropathy (mean amplitude reduction, 5.8 μV; 95% CI, 2.8-8.8; P < .001). Functional deficits were seen in manual dexterity, distal sensation, and balance. Patient-reported outcomes demonstrating reduction in global quality of life and physical functioning were associated with the Total Neuropathy Score. Cisplatin produced long-term neurotoxicity more frequently than vinca alkaloids. Clinical abnormalities attributable to peripheral neuropathy were common in childhood cancer survivors and persisted long term, with concurrent deficits in patient-reported outcomes. Both the type of neurotoxic agent and a targeted clinical neurological assessment are important considerations when screening survivors for long-term neuropathy. Further development of peripheral neuropathy-specific pediatric assessment tools will aid research into neuroprotective and rehabilitative strategies.

F30. Axonal variants of Guillain Barre Syndrome are predominant among nepalese population: A tertiary care center study

Introduction Guillain Barre Syndrome (GBS) is an acute, frequently severe, and fulminant polyradiculoneuropathy that is autoimmune in nature. Our aim is to classify GBS subtypes and evaluate the clinical severity. Methods All consecutive patients recruited prospectively in the study were of age ⩾ 16 years and were being admitted in department of Neurology of Tribhuvan University Teaching Hospital, Kathmandu, Nepal from 2016 March to 2017 February. All demographic, historical and clinical data were collected. Nerve conduction study, cerebrospinal fluid analysis along with clinical features were evaluated to assess the diagnostic certainty of Brighton Criteria. Overall disability sum score and GBS disability score were assessed in all patients. Results A total of 46 patients were included: male patients being predominant (70% vs 30%), mean age = 36.5 ± 16.2, range = 16–80 years. Thirty-two patients (70%) were axonal variant, acute motor axonal neuropathy being more common (18 patients), and 14 patients were acute motor and sensory axonal neuropathy. 14 patients (30%) were demyelinating type, out of which 11 patients had both motor and sensory features, and only 3 patients were pure motor demyelinating type. Axonal variants were found to have higher Overall disability sum score during nadir (p = 0.024) and discharge (p = 0.004), and also higher GBS disability score during nadir (p = 0.012) and discharge (p = 0.021). Acute motor axonal neuropathy (AMAN) had higher GBS disability score than acute inflammatory demyelinating polyneuropathy (AIDP) at nadir (p = 0.034) and discharge (p = 0.039). Conclusion AMAN subtype are predominant among Nepalese population. Axonal variants of GBS are clinically severe than demyelinating variants.

Guillain-Barre syndrome associated with hemorrhagic fever with renal syndrome in China: a case report

BackgroundWe describe a case of Guillain-Barre syndrome (GBS) associated with hemorrhagic fever with renal syndrome. To our knowledge, only five cases of GBS associated with Hantavirus infection have been reported so far.Case presentationsA 62-year-old man presented intermittent fever, chill and oliguria. According to remarkable leukocytosis, atypical lymphocytes, thrombocytopenia and former dwelling in hemorrhagic fever-endemic area, he was suspected as hemorrhagic fever with renal syndromeand certified with positive Hantavirus IgG. Later, the patient had symmetrical flaccid paralysis of all extremities. Electromyography showed peripheral nerve injury (mainly in axon). The patient was diagnosed as having acute motor sensory axonal neuropathy (AMSAN). After immunoglobulin infusion, patient showed progressive recovery and was transferred 3 weeks after his first admission to a rehabilitation center.ConclusionsOur case was the 6th reported case of GBS associated with hemorrhagic fever with renal syndrome. Moreover, we for the first time classified the subtype of GBS (AMSAN) based on the electrophysiology characteristics. GBS should be suspected in patients who are already diagnosed as hemorrhagic fever with renal syndrome when delayed symmetrical limb paralysis occurs. Until recent now, GBS was only reported in hemorrhagic fever patients in Europe and Asia, which termed as hemorrhagic fever with renal syndrome.

Predictors of respiratory failure in patients with Guillain-Barré syndrome: a systematic review and meta-analysis.

To systematically review the literature regarding the ability of clinical features to predict respiratory failure in patients with Guillain-Barré syndrome (GBS). We searched the PubMed and Ovid MEDLINE databases with the search terms "guillain barre syndrome" OR "acute inflammatory demyelinating polyneuropathy" OR "acute motor axonal neuropathy" OR "acute motor sensory axonal neuropathy" AND "respiratory failure" OR "mechanical ventilation". We excluded articles that did not report the results of original research (eg, review articles, letters), were case reports or series (ten or fewer patients), were not available in English, reported research in paediatric populations (16 years of age or younger), or were interventional studies. Article quality was assessed with the Newcastle-Ottawa quality assessment scale. Thirty-four relevant studies were identified. Short time from symptom onset to hospital admission (less than 7 days), bulbar (odds ratio [OR], 9.0; 95% CI, 3.94-20.6; P < 0.001) or neck weakness (OR, 6.36; 95% CI, 2.32-17.5; P < 0.001), and severe muscle weakness at hospital admission were associated with increased risk of intubation. Facial weakness (OR, 3.74; 95% CI, 2.05-6.81; P < 0.001) and autonomic instability (OR, 6.40; 95% CI, 2.83-14.5; P < 0.001) were significantly more frequent in patients requiring intubation in our meta-analyses; however, the differences were not statistically significant in individual multivariable analysis studies. Four predictive models have been developed to assess the risk of respiratory failure for patients with GBS, each with good to excellent discriminative power (area under the receiver operating characteristic curve, 0.79-0.96). Early identification of GBS patients at risk of respiratory failure could reduce the rates of adverse outcomes associated with delayed intubation. Algorithms that predict a patient's risk of subsequent respiratory failure at hospital admission appear more reliable than individual clinical variables.

Treatment of an acute motor and sensory axonal neuropathy with propionate in a 33-year-old male.

Background:The aim of this work was to report a case of an acute motor and sensory axonal neuropathy (AMSAN) treated with propionate to evaluate its therapeutic potential in AMSAN.Materials and methods:The patient was investigated by clinical examination, electroneurography, high-resolution nerve ultrasound and confocal corneal microscopy at baseline and the 2 month follow up. We compared the outcome with those of five other patients with acute motor axonal neuropathy (AMAN) and AMSAN of who were referred to our neurology department in the past 5 years.Results:Considering the poor prognosis of patients with acute axonal neuropathies and in comparison with the previously treated patients with AMAN or AMSAN in our clinic, the regression of our patient’s symptoms and the improvement in the additional examinations under propionate seemed exceptionally good.Conclusion:Propionate may have an additional therapeutic effect in autoimmune inflammatory neuropathies.

A case of acute motor sensory axonal neuropathy presenting reversible conduction block

A case of acute motor sensory axonal neuropathy presenting reversible conduction block

High-resolution ultrasound in patients with Wartenberg’s migrant sensory neuritis, a case-control study

ObjectiveWartenberg’s migrant sensory neuritis (WMSN) is a rare, patchy, pure sensory neuropathy of unknown etiology. High-resolution ultrasonography (HRUS) is an emerging diagnostic technique for neuropathies, but it has not been applied in WMSN. In this study we aimed to determine HRUS abnormalities in WMSN. MethodsWe performed a case-control study of 8 newly diagnosed patients with WMSN and 22 treatment-naive disease controls (16 patients with pure sensory axonal neuropathy and 6 with pure sensory chronic inflammatory demyelinating polyneuropathy (CIDP) or Lewis-Sumner syndrome (LSS)). All patients underwent routine diagnostic evaluations and a predefined HRUS protocol. ResultsWe found multifocal nerve enlargement in all 8 WMSN patients. The median nerve in the upper arm and the sural nerve were significantly larger in WMSN than in axonal controls (p = 0.01 and p = 0.04). In CIDP/LSS, sonographic enlargement was more extensive. Furthermore we found brachial plexus involvement in 3 of 8 (38%) WMSN patients. ConclusionHRUS showed enlargement of multiple nerves in all WMSN patients even if clinical testing and NCS were normal. SignificanceThe feature of multifocal nerve enlargement may be of additional value in establishing the diagnosis of WMSN and may support the suggestion of an auto-immune etiology.

83. Hyperreflexia in acute motor sensory axonal neuropathy: A case report

Guillain-Barre diagnostic criteria are the presence of acute, symmetric, progressive flaccid paralysis and areflexia, although cases of acute motor axonal neuropathy with increased deep tendon reflexes (DTRs) have been described. We report a patient with Acute Motor Sensory Axonal Neuropathy (AMSAN) with increased DTRs. A 48-year-old male presented with a two-day history of progressive acute lower limbs weakness and imbalance, following a flu-like syndrome. Neurological examination revealed ascending weakness, hyperactive DTRs, impairment of deep sensation and sensory ataxia. Spine magnetic resonance imaging and cerebrospinal fluid examination were normal. Nerve conduction study (NCS) showed a reduction of the sensory and motor action potentials amplitude with normal distal latencies and conduction velocities. A decreased H reflex threshold and high soleus H/M amplitude ratio (>0.7) were found. The patient was treated with intravenous immunoglobulins with progressive improvement. Repeat NCS, performed 10 and 21 days after symptoms onset, confirmed a sensory motor axonal neuropathy. Hyperreflexia has been rarely reported in AMSAN patients. As a possible cause of hyperreflexia, we hypothesized a selective involvement of the sensory Ia fibers, associated with dysfunction of spinal inhibitory interneurons.

Prospective comparison of acute motor axonal neuropathy and acute inflammatory demyelinating polyradiculoneuropathy in 140 children with Guillain–Barré syndrome in India

There have been few reports on subtypes of Guillain-Barré syndrome (GBS) in children. We compared clinical and laboratory findings of acute inflammatory demyelinating polyradiculoneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). One hundred forty children with GBS were included. Based on nerve conduction study (NCS) findings, patients were subclassified as AIDP, AMAN, acute motor sensory axonal neuropathy (AMSAN), and equivocal. Clinically, 72.1% of patients had pure motor, 24.3% motor sensory, and 3.4% Miller Fisher syndrome. Based on NCS, 67.8% of patients had AIDP, 23.6% had AMAN, and 4.3% had AMSAN. By 3 months, 2.1% patients had died, 47.1% had complete recovery, and 24.3% had poor recovery (wheelchair-bound). Children with AMAN had more frequent lower limb weakness (P = 0.02) and a lower probability of complete recovery (P = 0.01) at 3 months than children with AIDP (56% vs. 30%). AIDP is the most common GBS subtype in children. It is characterized by better recovery at 3 months when compared with AMAN. Muscle Nerve 57: 761-765, 2018.

Brainstem encephalitis and acute polyneuropathy associated with hepatitis E infection

A 59-year-old man presented with feverish illness. His Glasgow Coma Scale was 15, had reduced visual acuity in the left eye with partial left ptosis and mild left hemiparesis with...

S87 Issues in the electrodiagnosis of Guillain-Barré syndrome subtypes

Electrophysiology plays a determinant role in Guillain–Barre syndrome (GBS) diagnosis, classification of the subtypes and in establishing prognosis. Acute inflammatory demyelinating polyradiculoneuropathy (AIDP) has been electrophysiologically characterized by conduction slowing, conduction block, and temporal dispersion. Acute motor axonal neuropathy (AMAN) was initially thought to be characterized by simple axonal degeneration and the electrophysiological correlate limited to reduced amplitude of compound muscle action potentials. However AMAN and acute motor and sensory axonal neuropathy (AMSAN) patients show transient conduction block/slowing due to nodal dysfunction mimicking demyelination but without the development of abnormal temporal dispersion. This has been referred to as reversible conduction failure (RCF) and it is thought to be due to the attack of antiganglioside antibodies at the Ranvier node inducing a transitory dysfunction not progressing to axonal degeneration both in motor and sensory fibers. RCF it can be recognized only by serial studies and it is not included in the current electrodiagnostic criteria of GBS. The lack of distinction between RCF and demyelinating conduction block led to erroneous classification in up to 38% of patients. There is a need for an innovative approach to reach an earlier and more accurate electrodiagnosis based on a single study. In this talk the pitfalls in GBS electrodiagnosis will be highlighted and the inadequacy of current criteria discussed. A new criteria set for AIDP, AMAN and AMSAN, defining also the cut-offs for RCF in motor and sensory fibers, will be illustrated and the electrodiagnostic accuracy of a statistical method of supervised classification (sparse linear discriminant analysis) reported.

P236 Electrophysiological assessment of Guillain–Barre subtypes in a sample of IRAQI children

Objectives Assess the role of neurophysiological study (EMG and NCS) in the diagnosis of Guillain-Barre syndrome subtypes in children and estimate the frequency of subtypes whether demyelinating or axonal. Methods Two study groups of either sex were involved, (thirty) Guillain-Barre patients with different ages and (thirty) healthy subjects matched for age and gender served as control group. Each subject submitted to sensory and motor nerve conduction study (NCS) and electromyography (EMG) of both upper and lower limbs. Results Results revealed that (80%), (16.7%), (3.3%) of children had acute inflammatory demyelinating polyneuropathy (AIDP), acute motor axonal neuropathy (AMAN) and acute motor sensory axonal neuropathy (AMSAN) respectively. The H-reflex was absent in (73.3%) of patients. Discussion In this study AIDP was the most frequent type of GBS followed by AMAN then AMSAN, similarly a study from Iran reported that AIDP was the most frequent type among children, suggesting that; the incidence of AIDP in GBS differs geographically. H-reflex was absent in the majority (73.3%) of children, and this was lower than Gordon P.2001 where the absence of H-reflex was 97%, because of early time of examination. Conclusion Acute inflammatory demyelinating polyneuropathy (AIDP) is the most frequent subtype of GBS, the change in sensory and motor NCS parameters was higher in lower limbs than upper limbs. Proximal segments are more vulnerable to demyelination rather than intermediate or distal nerve segments. Significance The subtype differentiation is essential for the neurologist and the patient’s parents in identifying the recovery period.

Sensory motor axonal neuropathy and early onset osteotendinous contractures caused by mutation in MYH14

Sensory motor axonal neuropathy and early onset osteotendinous contractures caused by mutation in MYH14

Early discrimination of sensorimotor Guillain-Barré syndrome into demyelinating or axonal subtype by automated nerve excitability testing.

In the early stage of disease, differentiating acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor sensory axonal neuropathy (AMSAN) using only a conventional nerve conduction studies (NCS) may be difficult. We evaluated the differences in the motor axonal excitability properties of 16 cases of sensorimotor Guillain-Barré syndrome by nerve excitability testing (NET). The antiganglioside antibody assay and follow-up NCS resulted in 12 patients diagnosed as AIDP and 4 patients as AMSAN. Clinical and excitability parameters in each group were compared with those in 30 normal controls. Automated NET with threshold tracking techniques was used to calculate the strength-duration time constant (SDTC), threshold electrotonus (TE), current-threshold relationship (CTR), and recovery cycle (RC) of excitability. Except for subtle changes in excitability parameters, AIDP showed no definitive difference relative to normal controls. Comparison between AMSAN and normal controls also revealed no significant differences in the SDTC, TE, and CTR parameters. However, there were clear differences in some of the RC parameters: the relative refractory period was significantly longer in the AMSAN group than in the AIDP group (4.40 ± 1.11 vs. 3.09 ± 1.01 ms, mean ± SEM; p < 0.001), while superexcitability was significantly less prominent in the AMSAN group (-6.80 ± 10.30 vs. -26.48 ± 1.17%, mean ± SEM; p < 0.001). Our study identified that both AIDP and AMSAN were associated with subtle changes in excitability properties. Nonetheless, the prominent increase in refractoriness in AMSAN suggests the presence of a nodal conduction block.

Electrophysiological evaluation of Guillain–Barre syndrome subtypes in childhood

Background: Guillain-Barre syndrome (GBS) is the most common cause of acute motor paralysis in children where most of electrophysiological findings reveal demyelinating neuropathy. However, an axonal form of Guillain-Barre syndrome had been reported too.Objectives: Assess the role of neurophysiological study (EMG and NCS) in the diagnosis of Guillain-Barre syndrome subtypes in children and estimate the frequency of subtypes whether demyelinating or axonal form of Guillain-Barre syndrome.Subjects and methods: Two study groups of either sex was involved, thirty (30) Guillain-Barre patients with different ages and thirty(30) normal healthy subjects matched for age and gender served as control group. Each subject submitted to sensory and motor nerve conduction study (NCS) and electromyography (EMG) of both upper and lower limbs.Results:The results of this study revealed that 24 (80%), 5 (16.7%), 1 (3.3%) had Acute inflammatory demyelinating polyneuropathy, Acute motor axonal neuropathy and Acute motor sensory axonal neuropathy respectively. The most affected age group was (3-6) years, and the majority of patients had a preceding infection in the past 3 months. Furthermore, 29 patients out of 30 had lost deep tendon reflexes and the H-reflex was absent in 22 (73.3%), however, the F-wave was absent in lower limbs more than upper limbs (46.6%) and (26.6%) respectively. The distal motor latency was abnormal in 121 (82.3%) nerves out of 147 total examined nerves.Conclusion:Acute inflammatory demyelinating polyneuropathy (AIDP) is the most frequent subtype of GBS, the change in sensory and motor NCS parameters was higher in lower limbs than upper limbs. Proximal segments are more vulnerable to demyelination rather than intermediate or distal nerve segments.