Acquired hyperexcitable peripheral nerve disorders: Clinical and laboratory features, therapeutic responses, and long-term follow-up.

INTRODUCTION/AIMS: Hyperexcitable peripheral nerve disorders (HPNDs) are rare. Although their clinical and laboratory features have been well studied, information on treatment and follow-up is limited. The aim of this study is to explore the long-term clinical, investigative, and therapeutic profile of patients with acquired HPNDs. METHODS: This study retrospectively analyzed patients from a single tertiary care center with HPND (January 2012 to January 2022). Patients were recruited according to published inclusion and exclusion criteria. Details of clinical features, diagnostic tests, therapeutic interventions, and follow-up were recorded. This study included patients with follow-up of 2 or more years. RESULTS: A total of 32 patients (M = 26, F = 6) were studied. The common clinical features included myokymia, neuropathic or shock-like pain, cramps, sleep disturbances, encephalopathy, cerebellar ataxia, and seizures. A total of 81.25% of patients responded favorably to corticosteroids and membrane stabilizers. Among the nonresponders, five received intravenous immunoglobulin (IVIG), and one received plasma exchange (PLEX). Two patients required rituximab due to poor responses to the above treatments. The mean duration of response was 6 weeks (4-24 weeks) from the initiation of treatment. All patients had favorable outcomes, reaching clinical remission within 1-5 years from the initiation of treatment. Only two patients had relapses. Immunotherapy could be stopped in 78% of patients within 3 years and 100% by 5 years. DISCUSSION: Chronic immunosuppression starting with corticosteroids is required for satisfactory outcomes of HPNDs. These disorders usually run a monophasic course, and relapses are uncommon.

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.

Early and consistent pattern of proximal weakness in GNE myopathy.

BACKGROUND: GNE myopathy is widely regarded as a distal myopathy. Involvement of proximal musculature in this condition has not been systematically studied. METHODS: The phenotype of genetically confirmed patients with GNE myopathy was analyzed. Fourteen groups of muscles were evaluated with Medical Research Council (MRC) grading and the average muscle scores (AMS:1-10) were calculated. RESULTS: Fully documented AMS data was available in 31 of 65 patients. It showed a consistent pattern of severe weakness of hip adductors, hip flexors, knee flexors, and foot dorsiflexors, with milder weakness of the hip extensors and abductors. The knee extensors were largely unaffected. The proximal weakness appeared early in the course of the disease. Proximal muscle weakness was also present in the remaining 34 patients in whom the data were limited. A variant in exon 13 (c.2179G > A) was very common (81.5%). CONCLUSIONS: The GNE phenotype in this Indian cohort exhibited mixed proximal and distal involvement. Weakness of adductors and flexors of the hip formed an integral part of the phenotype.

Between the Person and the Pill: Factors Affecting Medication Adherence in Epilepsy Patients.

BACKGROUND: The majority of people afflicted with epilepsy live in developing countries. Poor adherence to prescribed medication is considered the main cause of unsuccessful drug treatment for epilepsy. Our study aims to evaluate the factors influencing medication adherence in epilepsy patients at a public hospital in Mumbai, India. METHOD: This cross-sectional study was carried out on a cohort of 313 epilepsy patients regularly attending an out-patient clinic at a tertiary-care hospital. A semi-structured questionnaire was used to assess demographic information, the level of medication adherence, and various factors that could influence adherence. Brief Illness Perception Questionnaire and WHO QoL-BREF Scale were also administered to the study population. RESULTS: Patients on anti-epilepsy medication reported an overall good quality of life and a good level of adherence. 90.1% of study participants reported being adherent with their treatment regimen. The main factors found to impact medication adherence were the duration of non-availability of medications in the public sector, and the monthly cost of the medications in the private sector. Other therapy-related, health system-related, socioeconomic, and psychosocial variables were not found to be significant determinants of medication nonadherence in our setting. CONCLUSION: Ensuring that anti-epilepsy drugs remain available in the public sector, and/or making them more affordable in the private sector are the main interventions likely to improve medication adherence in clinical settings such as ours.

Making sense of the clinical spectrum of limb girdle muscular dystrophies.

The expansion of the spectrum of limb girdle muscular dystrophies (LGMDs) in recent years means that neurologists need to be familiar with the clinical clues that can help with their diagnosis. The LGMDs comprise a group of genetic myopathies that manifest as chronic progressive weakness of hip and shoulder girdles. Their inheritance is either autosomal dominant (LGMD1) or autosomal recessive (LGMD2). Their prevalence varies in different regions of the world; certain ethnic groups have documented founder mutations and this knowledge can facilitate the diagnosis. The clinical approach to LGMDs uses the age at onset, genetic transmission and clinical patterns of muscular weakness. Helpful clinical features that help to differentiate the various subtypes include: predominant upper girdle weakness, disproportionate respiratory muscle involvement, distal weakness, hip adductor weakness, 'biceps lump' and 'diamond on quadriceps' sign, calf hypertrophy, contractures and cardiac involvement. Almost half of patients with LGMD have such clinical clues. Investigations such as serum creatine kinase, electrophysiology, muscle biopsy and genetic studies can complement the clinical examination. In this review, we discuss diagnostic clinical pointers and comment on the differential diagnosis and relevant investigations, using illustrative case studies.

Approach to Chronic Lymphocytic Meningitis.

Chronic meningitis is a common clinical problem. Early diagnosis and appropriate therapy is important in improving the overall outcome and to prevent long-lasting sequels. As many etiological agents lead to the development of chronic lymphocytic meningitis, it is important to develop a systematic approach to the diagnosis; taking clues from history, examination and laboratory tests, to make an accurate diagnosis and institute appropriate therapy. This review focuses on the diagnostic approach towards the commonly encountered situation of chronic lymphocytic meningitis. Chronic meningitis is defined as meningeal inflammation that persists for more than 4 weeks. Chronic meningitis accounts for less than 10% of all the cases of meningitis.1 Causes of chronic lymphocytic meningitis are mainly divided into infectious and non-infectious listed in Table 1.2 Due to advancement in investigations, diseases causing chronic meningitis may be diagnosed earlier than 4 weeks and hence the definition should be considered as a rough guideline.

A practical approach to enlargement of nerves, plexuses and roots.

Detecting enlargement of accessible nerves is very helpful in assessing patients with peripheral nerve disorders, as only a few types of neuropathy lead to nerve thickening. The three leading causes are leprosy, hereditary motor and sensory neuropathies (types 1 and 3) and chronic inflammatory demyelinating neuropathies. MRI, neurography and ultrasonography allow assessment of clinically inaccessible portions of deep-seated nerves, plexuses and roots. As a result, isolated proximal segment thickenings, as found in chronic inflammatory sensory polyradiculopathy, can now be better evaluated and managed. Similarly, focal nerve enlargements due to infection, inflammation, infiltration and neoplasm are being identified and treated effectively. We present a practical approach to the diagnosis and management of patients with enlarged peripheral nerves, plexuses and roots, including cranial nerves.

Once myasthenic, always myasthenic? observations on the behavior and prognosis of myasthenia gravis in a cohort of 100 patients.

BACKGROUND: The natural history of myasthenia gravis [MG] is unpredictable: In the first few years the disease course is worst with subsequent gradual disease stabilization. However, some patients tend to have continued disease activity or resurgence of the disease many years into the illness. The factors correlating with disease course need further evaluation. AIMS: To study the patterns of remissions, worsening and exacerbations in patients with MG and correlate various factors affecting them. SETTINGS AND DESIGN: Retrospective, Institute Review Board (IRB) approved study in tertiary referral neurology center. MATERIALS AND METHODS: Hundred patients with acquired MG confirming the inclusion criteria were studied. Pharmacological remissions, complete stable remissions, exacerbations, worsening episodes were analyzed with respect to age of onset, disease extent, disease severity at onset and worst of illness, acetyl choline receptor antibody positivity, thymectomy status, period of disease, pharmacotherapy and crisis episodes. RESULTS AND CONCLUSIONS: In this cohort the percentage of new remission rates per year steadily declined after the first year. Ocular myasthenia had lesser clinical worsening episodes and high chance of complete stable remission. Generalized disease had less chance drug free remission. The risk of episodes of worsening persisted at a steady rate over a period of time, being maximum in the first year. The risk of exacerbations was unpredictable and could occur after prolonged clinical quiescence, often was related to reduction of immunosuppression. The disease course did not differ significantly in the juvenile and adult age-groups. There was a strong case for permanent immunomodulation in MG.

Diagnostic Tests in Neoplastic Meningitis: Lessons Learnt from Three Patients.

Neoplastic meningitis (NM) poses diagnostic challenges and investigations need to be chosen carefully. We present three cases of NM with distinct learning points. In case 1, MRI was diagnostic of melanosis; in case 2, ventricular CSF showed malignant cells when lumbar CSF repeatedly failed to show them; and in the third, whole body PET scan diagnosed the tumour when other tests were negative. A comparative evaluation of various diagnostic modalities used in suspected NM is provided.

Ancestral founder mutations in calpain-3 in the Indian Agarwal community: historical, clinical, and molecular perspective.

INTRODUCTION: Clinical heterogeneity of limb-girdle muscular dystrophies (LGMDs, 24 known subtypes), which includes overlapping phenotypes and varying ages of onset and morbidity, adds complexity to clinical and molecular diagnoses. METHODS: To diagnose LGMD subtype, protein analysis, using immunohistochemistry (IHC) and immunoblotting, was followed by gene sequencing through a panel approach (simultaneous sequencing of known LGMD genes) in 9 patients from unrelated families of the Indian Agarwal community. Haplotype studies were performed by targeted SNP genotyping to establish mutation segregation. RESULTS: We identified 2 founder mutations in CAPN3, a missense (c.2338G>C; p.D780H) and a splice-site (c.2099-1G>T) mutation, on 2 different haplotype backgrounds. The patients were either heterozygous for both or homozygous for either of these mutations. CONCLUSIONS: Founder mutations have immediate clinical application, at least in selected population groups. Clinically available gene panels may provide a definitive molecular diagnosis for heterogeneous disorders such as LGMD.

Are syncopes in sitting and supine positions different? Body positions and syncope: a study of 111 patients.

CONTEXT: Syncope is a common cause of transient loss of consciousness. In the analysis of patients having syncope, body position has not been systematically studied and correlated with triggers, prodromal symptoms and circumstances. This correlation is important in differentiating syncope from its mimics. AIMS: To study syncope with respect to body positions, triggers, prodromal symptoms and circumstances. SETTINGS AND DESIGN: Prospective study set in Neurology Department of Tertiary Care Center. MATERIALS AND METHODS: Patients fulfilling guidelines set by The Task Force for the Diagnosis and Management of Syncope of the European Society of Cardiology (ESC) were recruited. Detailed clinical history, examination and investigations (ECG, 2D-ECHO, Head Up Tilt Test, Holter monitor, EEG, MRI Brain) were carried out. RESULTS: Out of the 111 recruited patients, 67 developed syncope in standing, 16 in sitting, 23 in both standing and sitting, 1 in both sitting and supine and 4 in all three positions. Prodromal symptoms were present in 81% while triggers in 42% and circumstances in 41% of patients. Black out, sweating, dizziness and headache were most common prodromal symptoms. Intense pain, smell and fear were most common triggers while prolonged standing, hot crowded room and fasting were most common circumstances associated with syncope. CONCLUSIONS: Against common belief, syncope can occur in sitting as well as in supine position. Emotional triggers were commoner in patients with syncope in supine and sitting positions while prodromal symptoms and circumstances were similar for all positions. Syncope should be considered in body positions other than standing.

Nodo-paranodopathies: Concepts, Clinical Implications, and Management.

Peripheral neuropathies are traditionally categorized into demyelinating or axonal. It has been proposed that dysfunction at nodal/paranodal region may be a key for better understanding of pathophysiology in patients with immune mediated neuropathies. In last few years, antibodies targeting node and paranode of myelinated nerves have been increasingly detected in patients with immune mediated neuropathies. These patients have clinical phenotype similar common inflammatory neuropathies like Guillain Barre syndrome and chronic inflammatory demyelinating polyradiculoneuropathy with some additional atypical neurological and systemic features, and they respond poorly to conventional first line immunotherapies like IVIG. This review summarizes the structure of the node, concept and pathophysiology of nodopathies. We provide an overview of clinical phenotypes in patients with specific nodal/paranodal antibodies, along with electrophysiological and other diagnostic features and suggest therapeutic line of management based on current evidence.

A case of non-Hodgkin lymphoma diagnosed after 35-month of initial presentation as recurrent vitritis with multiple negative biopsies.

To report a case of non-Hodgkin lymphoma (NHL) that was diagnosed 35-month of initial ocular manifestation. Retrospective chart review. A 53-year-old male presented with painless diminution of vision in both eyes. He subsequently underwent extensive laboratory investigations including multiple vitreous biopsies with a suspicion of intraocular lymphoma. Cytology from the vitreous aspirate failed to diagnose any relevant pathology. After 35-month from the onset of his ocular symptom, a brain biopsy revealed a round cell tumor suggestive of NHL. Even with high index of suspicion, consultation with ocular oncologist, imaging, and diagnostic vitrectomy, the diagnosis of lymphoma remains challenging.

Identification of deletions and duplications in the Duchenne muscular dystrophy gene and female carrier status in western India using combined methods of multiplex polymerase chain reaction and multiplex ligation-dependent probe amplification.

BACKGROUND: The technique of multiplex ligation-dependent probe amplification (MLPA) assay is an advanced technique to identify deletions and duplications of all the 79 exons of DMD gene in patients with Duchenne/Becker muscular dystrophy (DMD/BMD) and female carriers. AIM: To use MLPA assay to detect deletions which remained unidentified on multiplex polymerase chain reaction (mPCR) analysis, scanning 32 exons of the "hot spot" region. Besides knowing the deletions and/or duplications, MLPA was also used to determine the carrier status of the females at risk. MATERIALS AND METHODS: Twenty male patients showing no deletions on mPCR and 10 suspected carrier females were studied by MLPA assay using P-034 and P-035, probe sets (MRC Holland) covering all the 79 exons followed by capillary electrophoresis on sequencing system. RESULTS: On MLPA analysis, nine patients showed deletions of exons other than 32 exons screened by mPCR represented by absence of peak. Value of peak areas were double or more in four patients indicating duplications of exons. Carrier status was confirmed in 50% of females at risk. CONCLUSION: Combining the two techniques, mPCR followed by MLPA assay, has enabled more accurate detection and extent of deletions and duplications which otherwise would have remained unidentified, thereby increasing the mutation pick up rate. These findings have also allowed prediction of expected phenotype. Determining carrier status has a considerable significance in estimating the risk in future pregnancies and prenatal testing options to limit the birth of affected individuals.