US National Multiple Sclerosis Society, Multiple Sclerosis Society of Great Britain and Northern Ireland, Novartis, UK National Institute for Health Research (NIHR), and NIHR UCLH/UCL Biomedical Research Centre.

Objectives:Non-coeliac gluten sensitivity (NCGS) refers to patients with primarily gastrointestinal symptoms without enteropathy that symptomatically benefit from gluten-free diet (GFD). Little is known about its pathophysiology, propensity to neurological manifestations, and if these differ from patients with coeliac disease (CD). We investigated the clinical and immunological characteristics of patients presenting with neurological manifestations with CD and those with NCGS.Methods:We compared clinical, neurophysiological, and imaging data of patients with CD and NCGS presenting with neurological dysfunction assessed and followed up regularly over a period of 20 years.Results:Out of 700 patients, 562 were included. Exclusion criteria included no bowel biopsy to confirm CD, no HLA type available, and failure to adhere to GFD. All patients presented with neurological dysfunction and had circulating anti-gliadin antibodies. Out of 562 patients, 228 (41%) had evidence of enteropathy (Group 1, CD) and 334 (59%) did not (Group 2, NCGS). The most common neurological manifestations were cerebellar ataxia, peripheral neuropathy, and encephalopathy. There was a greater proportion of patients with encephalopathy in Group 1 and with a greater proportion of neuropathy in Group 2. The severity of ataxia did not differ between the two groups. Patients in Group 1 had more severe neuropathy. All patients from both groups responded to gluten-free diet. Anti-tissue transglutaminase (TG2) antibodies were found in 91% of patients in Group 1 and in 29% of patients in Group 2. Comparison between those patients in Group 2 with HLA-DQ2/DQ8 and those without as well as those with positive TG2 compared with those with negative TG2 antibodies identified no differences within these subgroups. Serological positivity for TG6 antibodies was similar in the two groups (67 and 60%).Conclusions:The neurological manifestations of CD and NCGS are similar and equally responsive to a GFD suggestive of common pathophysiological mechanisms.

Immune-mediated ataxias are common. Advances in genetic testing have significantly improved the diagnostic yield of patients suspected of having a genetic ataxia. Making a diagnosis of the cause of ataxia is essential due to potential therapeutic interventions for immune and some genetic ataxias.

We performed a retrospective study to validate whether a disposable concentric needle electrode (CNE) can be used in place of a single-fiber (SF) electrode for jitter measurements in myasthenia gravis (MG). Normal values for voluntary contraction of orbicularis oculi (OO) and extensor digitorum communis (EDC) were collected from 20 healthy subjects. The method was validated by a retrospective analysis of 56 consecutive MG patients, the "gold standard" being a positive acetylcholine receptor (AChR) antibody titer at the time of the electrophysiological (electromyography) study and the clinical diagnosis. Receiver operating characteristic (ROC) curves were constructed to define maximal sensitivity and specificity of the technique. The sensitivity was 96.4% (95% confidence interval 87.5%-99.6%), with no false-positive results, similar to traditional SF EMG and confirming that the disposable CNE is a justifiable alternative. Single-fiber electromyography (SF EMG) was established by Stälberg and Ekstedt in the 1960s and is of proven value in the diagnosis of neuromuscular junction disorders such as myasthenia gravis (MG). 10,11 Normal limits have been established for the SF needle electrode across different centers and age groups of patients, using both voluntary contraction and electrical nerve stimulation. 1,3 The validity of the technique has been proven by examining a large number of MG patients, and a sensitivity of up to 99% in detecting a neuromuscular transmission defect in generalized myasthenia gravis has been reported. 11 Several workers have modified the standard jitter technique by using a monopolar or concentric needle electrode, with appropriate low-cut filters, and have successfully measured neuromuscular jitter in a limited number of patients. 4 -6,17 With increasing concern about possible transmission of prion disease by iatrogenic means, especially after the isolation of prion proteins in muscle specimens of affected patients, 7 and the recognized difficulty of removing proteins from metal surfaces by conventional sterilization, 15 it was decided to adopt the disposable concentric needle electrode (CNE) for quantitative study of neuromuscular jitter at our institution.In order to evaluate the sensitivity of the modified jitter measurement technique, using a smallcaliber CNE with voluntary contraction, we obtained values from the orbicularis oculi (OO) and the extensor digitorum communis (EDC) muscles from 20 normal subjects and 56 consecutive patients with a clinical diagnosis of MG and positive antibody titers to the nicotinic acetylcholine receptor (AChR). 16 MATERIALS AND METHODSSubjects. Values for quantitative SF EMG studies using a CNE in OO and EDC were obtained in 20 normal subjects, 9 men and 11 women. Their ages ranged from 22 to 60 years (mean, 39 years). None had symptoms of a medical condition and none was taking medication that could have interfered with the study. Informed consent was obtained and the study was approved by our institutional review board.

Chronic idiopathic axonal polyneuropathy (CIAP) is a term describing neuropathies with both sensory and motor involvement in a length dependant distribution where neurophysiology reveals axonal damage, neuropathy onset is insidious and shows slow or no progression of the disease over at least 6 months with no aetiology being identified despite appropriate investigations. This entity merits further consideration given how common it is, the absence of clarity regarding aetiopathogenesis, natural history and therapies. A systematic computer-based literature search was conducted on PubMed database. We used two Medical Subject Headings terms in title. Term A was "axonal", "cryptogenic", "idiopathic" or "unknown" and Term B was "neuropathy" or "polyneuropathy". This search strategy resulted in the identification of 658 articles. After eligibility assessment, 48 papers were used for this review. CIAP is usually diagnosed in the sixth decade of life and it is more prevalent in males (ratio 3:2). It is usually slowly progressive. Some data support a potential role of autoimmunity in CIAP and further larger prospective studies are required to address such potential link and any treatment implications. CIAP is a common type of polyneuropathy but the least studied. Increasing awareness and research into this entity may result in better understanding and in the development of treatment strategies.