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.

Guidelines versus ground lines: Tuberculosis of the central nervous system.

AIM: This questionnaire-based national survey is aimed at understanding the patterns of practice of various aspects of central nervous system (CNS) tuberculosis (TB) among neurologists. SETTINGS AND DESIGN: Neurology department of a tertiary medical college. MATERIALS AND METHODS: A questionnaire was sent through email to all practicing neurologists in India. The responses were analyzed. STATISTICAL ANALYSIS: Inferential statistics. RESULTS: In all, 144 responses were received (out of the 853 questionnaires sent). The major discrepancies were in the primary antitubercular drug regimen (HRZE + HR), duration for tubercular meningitis (TBM) [12 months] and tuberculoma (12-18 months) to develop, follow-up (varied), linezolid use (varied), proportion of drug-resistant cases (<25%), and not taking histological aids (91%). The cerebrospinal fluid (CSF) TB polymerase chain reaction (PCR) utility (75%), not using CSF adenosine deaminase [ADA] (58%), the strategy to stop antitubercular drugs, and the use of steroids (77%) were according to guidelines. CONCLUSION: The present survey, for the first time, provides ground-level evidence of various aspects of CNS TB as practiced by neurologists in India. The major diversity was observed in therapeutics such as the choice of antitubercular drugs, its duration, linezolid use beyond the recommended duration, and knowledge of drug resistance. The monitoring aspects of CNS TB also showed variations. The investigational aspects of CNS TB such as using TB PCR, not using CSF ADA, and regular neuroimaging revealed a good clinical practice. Other CSF parameters require uniformity. This survey thus helps to identify areas of future work in CNS TB in India.

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.

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.

Reversible central neural hyperexcitability: an electroencephalographic clue to hypocalcaemia.

A 23-year-old male patient presented with cognitive decline and seizures. Examination revealed Chvostek's and Trousseau's signs. Investigations revealed hypocalcaemia, hyperphosphatemia and normal intact parathyroid hormone levels. Imaging showed calcifications in bilateral basal ganglia, thalamus and dentate nuclei. Interictal electroencephalogram showed theta range slowing of background activity and bilateral temporo-occipital, irregular, sharp and slow wave discharges, which accentuated during hyperventilation, photic stimulation and eye closure. Appearance of epileptiform discharges after eye closure, hyperventilation and photic stimulation may suggest presence of central neural hyperexcitability due to hypocalcaemia. These features may be an equivalent of peripheral neuromuscular hyperexcitability (Chvostek's and Trousseau's signs) that occurs in hypocalcaemia. The clinical and electroencephalographic features completely reversed with correction of serum calcium without antiepileptic medications. It is important for clinicians to recognise these reversible changes, as it can help to avoid misdiagnosis and long-term administration of antiepileptic becomes unnecessary.