Chronic immune polyradiculopathies: Three clinical variants of one disease?

INTRODUCTION: Chronic immune polyradiculopathies (sensory, motor, and mixed) are uncommon. METHODS: In this single-center, retrospective study, the inclusion criteria for participants were progressive sensory ataxia and/or areflexic limb weakness; tibial somatosensory evoked potential (SSEP) abnormalities of the N22 and P40 potentials with normal sensory and motor nerve conduction studies or root involvement, according to magnetic resonance imaging (MRI); and albuminocytological dissociation. RESULTS: Eight patients were included in our study. Two had weakness, two had sensory ataxia, and four had both weakness and ataxia. Patients with weakness had abnormal SSEPs and patients with sensory ataxia also had absent F waves. Electromyography showed chronic denervation. MRI scans confirmed thickening and enhancement of roots. The patients responded to corticosteroid treatment. DISCUSSION: The overlapping clinicoelectrophysiological findings and similarities in radiological and therapeutic responses suggest that these entities are clinical variants of the same disease. The terms CIS(m)P, CI(s)MP, and CISMP (for chronic immune sensory motor polyradiculopathy) could be used to denote the predominant clinical involvement.

Two cases of chronic immune sensorimotor polyradiculopathy: Expanding the spectrum of chronic immune polyradiculopathies.

INTRODUCTION: Immune-mediated demyelinating radiculopathies restricted to proximal sensory or motor roots are uncommon. METHODS: We report the clinical, electrophysiological, biochemical, and radiological features in 2 patients with chronic immune sensorimotor polyradiculopathy (CISMP). RESULTS: The patients presented with sensory ataxia, weakness of the lower limbs, and areflexia. Electrophysiological studies revealed involvement of proximal sensorimotor roots, as evidenced by changes in somatosensory evoked potentials, F-waves, and H-reflexes. In contrast, the distal nerve segments were normal. Magnetic resonance neurography findings of thickened and enhanced roots supported the electrophysiological findings. The response to immunosuppressive therapy was favorable in both patients. CONCLUSION: The findings from these 2 patients further expand the knowledge spectrum of immune polyradiculopathies. Muscle Nerve 55:135-137, 2017.

Medial Plantar Sensory Nerve Action Potential: A Study for Reference Data in Indian Subjects.

Context: The medial plantar nerve (MP) sensory nerve action potential (SNAP) has been shown to be a sensitive indicator for detecting a length-dependent axonal peripheral neuropathy. However, literature survey shows paucity of age stratified data. This study was undertaken to obtain age stratified reference data for MP SNAP amplitude and latency. Aim: To establish age-stratified reference data in Indian subjects for the MP SNAP. Study Setting and Design: The study was conducted in the electrodiagnostic laboratory of a tertiary city hospital and is retrospective study. Materials and Methods: A retrospective study was conducted using the nerve conduction study reports of 173 patients with only upper limb symptoms and findings. Patients were between the ages of 18 and 86 years, stratified into six groups, a = 18-30 years, b = 31- 40 years, c = 41-50 years, d = 51- 60 years, e = 61-70 years, f ≥70 years. Statistical Methods: Stata 12.1 statistical program was used. Lower limit of the SNAP amplitude was obtained using mean-2SD of transformed data. Analysis of variance defined the intergroup variability, linear regression and Pearson's correlation assessed the statistical significance. Results: The lower limit of normal MP SNAP amplitude for each age group is as follows: a: 8.7uv b: 7.5uv c: 3.7 uv d: 2.9uv e: 2.0 uv f: 1.4uv. The amplitude difference between the groups b & c, c & d and e and f using analysis of variance with Bonferroni correction and Tukey post-hoc test was not significant, but the other groups showed statistically significant variance. The equation of regression for the predicted amplitude value with age was defined as Y^ = {3.5 + age (-.0233) - 2 (0.389)}3. Conclusion: This study provides age stratified reference data for MP SNAP. There is evidence to suggest that MP SNAP amplitude varies with age hence age stratified data should be used to define abnormality.

Optimizing Investigations for Evaluation of Enlargements of the Roots, Plexuses and Nerves: A Study of 133 Patients.

BACKGROUND AND AIMS: A wide variety of neurological diseases result in clinical and/or radiological enlargement of nerves, roots and plexuses. With the advancement in techniques and use of magnetic resonance neurography (MRN), aided by electrophysiology, proximal segments of the lower motor neuron (LMN) can be well studied. The relative merits of investigative modalities have not been well defined and comprehensive information on this subject is sparse. METHODS: This retrospective study included data from January 2010 to June 2018. Patients having clinical and/or radiological enlargements of lower motor neuron were included. Clinical and laboratory work up, electrophysiology, MRN and biopsy studies were documented and analyzed. RESULTS: 133 patients fulfilled the inclusion criteria. The diagnostic categories were of leprosy (32%), immune neuropathies (27.8%), nerve infiltrations (8.2%), inherited neuropathies (9%), diabetic radiculopathies (9%) and others (12.7%). MRN was essential to diagnosis in 24.8% and supportive in 31.5% patients. Electrophysiology was essential in diagnosis in 70.6%, biopsy in 45.8% and genetic studies in 6.4% patients. CONCLUSION: The manuscript presents a large cohort of diseases causing enlargement of LMN with clinical and investigative aspects of 7 patients of the most unusual condition of chronic immune sensorimotor polyradiculopathy (CISMP) and details of 7 other patients with chronic mononeuropathies at non-entrapment sites. A table of comparative utility and an algorithm depicting the optimization of investigations has been presented.

Interpretation of electroneuromyographic studies in diseases of neuromuscular junction and myopathies.

Electroneuromyography (ENMG) also called electrodiagnosis or at times simply (and erroneously) electromyography (EMG), has been used for the diagnosis of neuromuscular and muscle diseases. It consists of tests done serially and assessed collectively, to arrive at a diagnosis of neuromuscular weakness. The test should be treated as an extension of the clinical examination and not a replacement. When done adequately ENMG is the only test which gives information about the function of the peripheral nervous system and hence co-relates well with the clinical signs. This article reviews the role of ENMG in the evaluation of neuromuscular and muscle disease. We hope this will meet the requirements of both practicing neurologists and dedicated electromyographers.

Epidemiological Survey of Neurological Diseases in a Tribal Population Cluster in Gujarat.

BACKGROUND: There are few community-based neuroepidemiological studies based in tribal communities. This cross-sectional community-based study explored the prevalence rates of neurological disorders in the tribal region of Kaparada in Gujarat. METHODOLOGY: A two-stage methodology was used. Door-to-door surveys were conducted in the villages of Moti Vahiyal, Arnai, and Chavshala in Kaparada taluka in the Valsad district. Trained volunteers administered a questionnaire that assessed demographic details and common neurological symptoms in children and adults. Data were obtained from 8217 individuals from 1464 households using the questionnaire in stage 1. A number of 615 individuals reported at least one symptom. In stage 2, a team of neurologists conducted a medical camp to assess those "screened in" for neurological disorders. RESULTS: The crude prevalence rate for neurological disorders in general was found to be 2592.19/100,000. The prevalence rates for lower motor neuron diseases were highest (1010.1), and the rates of epilepsy, movement disorders, stroke, vertigo, headaches, upper motor neuron diseases, and mental and behavioral disorders were found to be 255.6, 133.9, 109.53, 170.38, 511.4, 109.53, and 292.08/100,000, respectively. Age- and sex-specific rates and patterns varied for different disorders. CONCLUSION: The prevalence rates of most disorders were found to be lower than those reported elsewhere, but age and sex prevalence patterns were similar to existing research. Challenges in conducting such a study in a remote population are discussed.

Clinico-Electrophysiological and Genetic Overlaps and Magnetic Resonance Imaging Findings in Charcot-Marie- Tooth Disease: A Pilot Study from Western India.

BACKGROUND: Charcot-Marie-Tooth (CMT) disease is clinically and genetically heterogeneous. There are no published series describing clinical, electrophysiological, and genetic information on CMT from the Indian subcontinent. Magnetic resonance imaging (MRI) neurography technique provides useful information about the plexus and roots and can be employed in patients with CMT. SETTINGS AND DESIGN: A prospective, observational study carried out at a tertiary care hospital in Western India. SUBJECTS AND METHODS: CMT patients fulfilling the UK Genetic Testing Network criteria were included. They underwent clinical, electrophysiological, radiological, and multigene panel testing. RESULTS: Totally 22 patients (19 males, 3 females; 18 sporadic and 4 familial cases) were studied. Pes cavus (19), hammer toes (16), and scoliosis was seen in 1 patient. Electrophysiology revealed motor predominant neuropathy with 15 demyelinating (10 uniform and 5 multifocal) and 7 axonal patterns. Thickened lumbosacral plexuses on MRI neurography were evident in 6/10 studied patients, all 6 having demyelinating neuropathy. Genetic analysis identified PMP22, GJB1, SH3TC2, HSPB1, SPTLC2, MPZ, AARS, and NEFH gene mutations. CONCLUSIONS: This small series documents the pattern of CMT neuropathies as seen in Western India. Clinico-electrophysiological and genetic diagnosis showed general concordance some overlaps and reiterated advantages of gene panel testing in this heterogeneous group of neuropathies. MRI neurography was useful as an additional investigation to detect nerve enlargement in patients with demyelinating neuropathies.

Sural sensory nerve action potential: A study in healthy Indian subjects.

BACKGROUND: The sural sensory nerve action potential (SNAP) is an important electrodiagnostic study for suspected peripheral neuropathies. Incorrect technique and unavailability of reference data can lead to erroneous conclusions. OBJECTIVES: To establish reference data for sural SNAP in age-stratified healthy subjects at three sites of stimulation. MATERIALS AND METHODS: A prospective study was conducted in 146 nerves from healthy subjects aged between 18 years and 90 years, stratified into six age groups (a = 18-30 years, b = 31-40 years, c = 41-50 years, d = 51-60 years, e = 61-70 years, and f >71 years). Sural SNAP was recorded antidromically, stimulating at three sites at distances of 14 cm, 12 cm, and 10 cm from the recording electrode. Mean - 2 standard deviation (SD) of the transformed data was used to generate reference values for amplitudes. Analysis of variance (ANOVA) test was used for inter-group and between three sites comparisons of amplitudes. RESULTS: The lower limits of amplitude at 14 cm were 12.4 µV, 10.4 µV, 6.5 µV, 5.3 µV, 2.9 µV, and 1.9 µV; at 12 cm were 13.5 µV, 13.6 µV, 8.5 µV, 7.8 µV, 3.5 µV, and 2.8 µV; and at 10 cm were 16.3 µV, 16.3 µV, 11.1 µV, 10.0 µV, 4.8 µV, and 3.7 µV for groups a, b, c, d, e, and f, respectively. A statistically significant difference in amplitudes was noted from the three different sites of stimulation (P < 0.001). The amplitude differed significantly above the age of 60 years (P < 0.01) but not between groups e and f (P > 0.05). CONCLUSION: This study provides reference data for sural SNAP in Indian population at three different sites of stimulation along the calf in six age groups. It also shows significant variation in amplitude from the three different sites of stimulation.

Compressive neuropathy in the upper limb.

Entrampment neuropathy or compression neuropathy is a fairly common problem in the upper limb. Carpal tunnel syndrome is the commonest, followed by Cubital tunnel compression or Ulnar Neuropathy at Elbow. There are rarer entities like supinator syndrome and pronator syndrome affecting the Radial and Median nerves respectively. This article seeks to review comprehensively the pathophysiology, Anatomy and treatment of these conditions in a way that is intended for the practicing Hand Surgeon as well as postgraduates in training. It is generally a rewarding exercise to treat these conditions because they generally do well after corrective surgery. Diagnostic guidelines, treatment protocols and surgical technique has been discussed.