Encephalopathy with Guillain-Barré syndrome: seek a different cause.

A 30-year-old woman developed symptoms, signs and neurophysiology consistent with Guillain-Barré syndrome and was admitted to the neurosciences intensive care unit owing to respiratory compromise. Here, she received a clonidine infusion for agitation, complicated by a minor hypotensive episode, following which she became unconscious. MR scan of the brain showed changes compatible with hypoxic brain injury. Urinary amino acids showed increased urinary α-ketoglutarate. Genetic testing using whole-exome sequencing identified pathogenic variants in the SLC13A3 gene known to be associated with an acute reversible leukoencephalopathy with increased urinary α-ketoglutarate. The case highlights the importance of considering inborn errors of metabolism in cases of unexplained encephalopathy.

Clinical Characteristics and Management of 50 Patients with Anti-GAD Ataxia: Gluten-Free Diet Has a Major Impact.

The objective of this study is to report the clinical characteristics and treatment of patients with progressive cerebellar ataxia associated with anti-GAD antibodies. We performed a retrospective review of all patients with anti-GAD ataxia managed at the Sheffield Ataxia Centre over the last 25 years. We identified 50 patients (62% females) with anti-GAD ataxia. The prevalence was 2.5% amongst 2000 patients with progressive ataxia of various causes. Mean age at onset was 55 and mean duration 8 years. Gaze-evoked nystagmus was present in 26%, cerebellar dysarthria in 26%, limb ataxia in 44% and gait ataxia in 100%. Nine patients (18%) had severe, 12 (24%) moderate and 29 (58%) mild ataxia. Ninety percent of patients had a history of additional autoimmune diseases. Family history of autoimmune diseases was seen in 52%. Baseline MR spectroscopy of the vermis was abnormal at presentation in 72%. Thirty-five patients (70%) had serological evidence of gluten sensitivity. All 35 went on gluten-free diet (GFD). Eighteen (51%) improved, 13 (37%) stabilised, 3 have started the GFD too recently to draw conclusions and one deteriorated. Mycophenolate was used in 16 patients, 7 (44%) improved, 2 stabilised, 6 have started the medication too recently to draw conclusions and one did not tolerate the drug. There is considerable overlap between anti-GAD ataxia and gluten ataxia. For those patients with both, strict GFD alone can be an effective treatment. Patients with anti-GAD ataxia and no gluten sensitivity respond well to immunosuppression.

Treatment of Primary Autoimmune Cerebellar Ataxia with Mycophenolate.

Immune-mediated ataxias account for a substantial number of sporadic otherwise idiopathic ataxias. Despite some well-characterised entities such as paraneoplastic cerebellar degeneration where diagnostic markers exist, the majority of immune ataxias remained undiagnosed and untreated. We present here our experience in the treatment of suspected primary autoimmune cerebellar ataxia (PACA) using mycophenolate. All patients reported attend the Sheffield Ataxia Centre on a regular basis and had undergone extensive investigations, including genetic testing using next-generation sequencing, with other causes of ataxia excluded. The diagnosis of PACA was strongly suspected based on investigations, pattern of disease progression, and cerebellar involvement. Patients were treated with mycophenolate and monitored using MR spectroscopy of the cerebellar vermis. Thirty patients with PACA are reported here. Of these, 22 received mycophenolate (group 1). The remaining 8 were not on treatment (group 2-control group). Out of the 22 treated patients, 4 underwent serial MR spectroscopy prior to starting treatment and thus were used as controls making the total number of patients in the control group 12. The mean change of the MRS within the vermis (NAA/Cr area ratio) in the treatment group was + 0.144 ± 0.09 (improved) and in the untreated group - 0.155 ± 0.06 (deteriorated). The difference was significant. We also demonstrated a strong correlation between the spectroscopy and the SARA score. We have demonstrated the effectiveness of mycophenolate in the treatment of PACA. The results suggest that immune-mediated ataxias are potentially treatable, and that there is a need for early diagnosis to prevent permanent neurological deficit. The recently published diagnostic criteria for PACA would hopefully aid the diagnosis and treatment of this entity.

An unusual case of inflammatory meningitis in a young man with systemic lupus erythematosus.

We describe a man presenting with unusual neurological manifestations of systemic lupus erythematosus (SLE) including pachymeningitis, aseptic meningitis and encephalitis with grossly elevated cerebrospinal fluid protein, responding to immunosuppression. Initially he had intermittent dysarthria, dysphasia and unilateral upper limb weakness. One month later he experienced dysphasia, right-sided hemiparesis and confusion. Cerebrospinal fluid (CSF) analysis showed a white cell count of 70 x 106/litre and an unusually elevated protein level of 5.39 g/litre. An MRI brain showed dural and leptomeningeal enhancement compatible with a meningitic process. He improved with cefotaxime and aciclovir. On day seven of antimicrobials he developed left-sided weakness, sensory inattention and a left homonymous hemianopia. He responded well to intravenous methylprednisolone. On switching to oral prednisolone he developed expressive dysphasia, a right inferior quadrantanopia and seizures. His bloods were suggestive of macrophage activation syndrome. The patient improved with methylprednisolone and intravenous immunoglobulins, and the improvement was sustained on switching back to oral prednisolone. The prevalence of neuropsychiatric manifestations of SLE varies between 14 and 80% and according to the American College of Rheumatology includes 19 conditions. This case is unique because although some features were in keeping with aseptic meningitis the MRI appearances were also suggestive of pachymeningitis.

Characterization of Paroxysmal Gluten-Sensitive Dyskinesia in Border Terriers Using Serological Markers.

BACKGROUND: Paroxysmal gluten-sensitive dyskinesia (PGSD) in border terriers (BTs) results from an immunologic response directed against transglutaminase (TG)2 and gliadin. Recent evidence suggests that PGSD is only one aspect of a range of possible manifestations of gluten sensitivity in the breed. HYPOTHESIS/OBJECTIVES: Gluten sensitivity in BTs is a heterogeneous disease process with a diverse clinical spectrum; to characterize the phenotype of PGSD using TG2 and gliadin autoantibodies as diagnostic markers. ANIMALS: One hundred twenty-eight client-owned BTs with various disorders. METHODS: Prospective study. BTs with paroxysmal episodes and a normal interictal examination were phenotyped using footage of a representative episode and assigned to 3 groups: idiopathic epilepsy (IE), paroxysmal dyskinesia (PD), or other. Owners of each dog completed a questionnaire to obtain information regarding clinical signs. Healthy BTs formed a control group. Serum antibodies against TG2 and AGA were measured in all dogs. RESULTS: One hundred twenty-eight BTs were enrolled; 45 with PD, 28 with IE, 35 with other conditions, and 20 controls. Three overlapping phenotypes were identified; PD, signs suggestive of gastrointestinal disease, and dermatopathy. AGA-IgG concentrations were increased in PD, compared with IE (P = 0.012), controls (P < 0.0001) and other (P = 0.018) conditions. Anti-canine TG2-IgA concentrations were increased in PD, compared with IE (P < 0.0001), controls (P < 0.0001) and other (P = 0.012) conditions. Serological markers are highly specific for PGSD but lack sensitivity. CONCLUSIONS: PGSD appears part of a syndrome of gluten intolerance consisting of episodes of transient dyskinesia, signs suggestive of gastrointestinal disease, and dermatological hypersensitivity.

Causes of progressive cerebellar ataxia: prospective evaluation of 1500 patients.

BACKGROUND: Cerebellar ataxias are the result of diverse disease processes that can be genetic or acquired. Establishing a diagnosis requires a methodical approach with expert clinical evaluation and investigations. We describe the causes of ataxia in 1500 patients with cerebellar ataxia. METHODS: All patients were referred to the Sheffield Ataxia Centre, UK, and underwent extensive investigations, including, where appropriate genetic testing using next-generation sequencing (NGS). Patients were followed up on a 6-monthly basis for reassessment and further investigations if indicated. RESULTS: A total of 1500 patients were assessed over 20 years. Twenty per cent had a family history, the remaining having sporadic ataxia. The commonest cause of sporadic ataxia was gluten ataxia (25%). A genetic cause was identified in 156 (13%) of sporadic cases with other causes being alcohol excess (12%) and cerebellar variant of multiple system atrophy (11%). Using NGS, positive results were obtained in 32% of 146 patients tested. The commonest ataxia identified was EA2. A genetic diagnosis was achieved in 57% of all familial ataxias. The commonest genetic ataxias were Friedreich's ataxia (22%), SCA6 (14%), EA2 (13%), SPG7 (10%) and mitochondrial disease (10%). The diagnostic yield following attendance at the Sheffield Ataxia Centre was 63%. CONCLUSIONS: 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.

A presumptive case of gluten sensitivity in a border terrier: a multisystem disorder?

Paroxysmal gluten-sensitive dyskinesia (previously termed canine epileptoid cramping syndrome) is a condition of Border terriers in which the leading manifestation is neurological. The authors describe a case they believe to represent the first report of a Border terrier with a combination of neurological signs, atopy, positive serological results for anti-transglutaminase 2 (TG2 IgA) and anti-gliadin (AGA IgG) antibodies, and signs suggestive of gastrointestinal disease with pathological changes in the gastrointestinal tract-seemingly responsive to a gluten-free diet. As such, the authors suggest that gluten sensitivity in Border terriers may manifest as a multisystem disease in a similar manner to that seen in human beings.

The Clinical and Serological Effect of a Gluten-Free Diet in Border Terriers with Epileptoid Cramping Syndrome.

BACKGROUND: Canine epileptoid cramping syndrome (CECS) is a paroxysmal movement disorder of Border Terriers (BTs). These dogs might respond to a gluten-free diet. OBJECTIVES: The objective of this study was to examine the clinical and serological effect of a gluten-free diet in BTs with CECS. ANIMALS: Six client-owned BTs with clinically confirmed CECS. METHODS: Dogs were prospectively recruited that had at least a 6-month history of CECS based on the observed phenomenology (using video) and had exhibited at least 2 separate episodes on different days. Dogs were tested for anti-transglutaminase 2 (TG2 IgA) and anti-gliadin (AGA IgG) antibodies in the serum at presentation, and 3, 6, and 9 months after the introduction of a gluten-free diet. Duodenal biopsies were performed in 1 dog. RESULTS: Serum TG2 IgA titers were increased in 6/6 BTs (P = .006) and AGA IgG titers were increased in 5/6 BTs at presentation compared to those of controls (P = .018). After 9 months, there was clinical and serological improvement in all BTs with CECS strictly adhering to a gluten-free diet (5/5). One dog had persistently increased antibody titers. This dog scavenged horse manure. On the strict introduction of a gluten-free diet this dog also had an improved clinical and serological response. The diet-associated improvement was reversible in 2 dogs on completion of the study, both of which suffered a relapse of CECS on the re-introduction of gluten. CONCLUSIONS: Canine epileptoid cramping syndrome in BTs is a gluten-sensitive movement disorder triggered and perpetuated by gluten and thus responsive to a gluten-free diet.

Consensus paper: radiological biomarkers of cerebellar diseases.

Hereditary and sporadic cerebellar ataxias represent a vast and still growing group of diseases whose diagnosis and differentiation cannot only rely on clinical evaluation. Brain imaging including magnetic resonance (MR) and nuclear medicine techniques allows for characterization of structural and functional abnormalities underlying symptomatic ataxias. These methods thus constitute a potential source of radiological biomarkers, which could be used to identify these diseases and differentiate subgroups of them, and to assess their severity and their evolution. Such biomarkers mainly comprise qualitative and quantitative data obtained from MR including proton spectroscopy, diffusion imaging, tractography, voxel-based morphometry, functional imaging during task execution or in a resting state, and from SPETC and PET with several radiotracers. In the current article, we aim to illustrate briefly some applications of these neuroimaging tools to evaluation of cerebellar disorders such as inherited cerebellar ataxia, fetal developmental malformations, and immune-mediated cerebellar diseases and of neurodegenerative or early-developing diseases, such as dementia and autism in which cerebellar involvement is an emerging feature. Although these radiological biomarkers appear promising and helpful to better understand ataxia-related anatomical and physiological impairments, to date, very few of them have turned out to be specific for a given ataxia with atrophy of the cerebellar system being the main and the most usual alteration being observed. Consequently, much remains to be done to establish sensitivity, specificity, and reproducibility of available MR and nuclear medicine features as diagnostic, progression and surrogate biomarkers in clinical routine.

Brain structure and function in patients after metal-on-metal hip resurfacing.

BACKGROUND AND PURPOSE: Hip prostheses that use a metal-on-metal articulation expose the brain to elevated metal concentrations that, in acute excess due to prosthesis malfunction, is associated with neurologic damage, including visual and hearing loss and motor deficits. Here, we examined whether chronic exposure to lower elevated metal levels, typical of well-functioning prostheses, also affects brain structure and function. MATERIALS AND METHODS: We compared brain volumes, metal deposition, and gray matter attenuation by MR imaging and clinical neurologic function in patients 8 years after receiving a metal-on-metal hip resurfacing versus a matched group of patients with the same duration exposure to a conventional hip prosthesis. RESULTS: Twenty-nine patients (25 men; mean, age 59±7 years) after metal-on-metal hip resurfacing and 29 patients (25 men; 59±8 years) after total hip arthroplasty were compared. Whole blood cobalt and chromium concentrations were 5-10 times higher in the metal-on-metal hip resurfacing group (P<.0001). Occipital cortex gray matter attenuation tended to be lower (P<.005 uncorrected, P>.05 corrected), and the optic chiasm area tended to be lower (mean difference, -2.7 mm2; P=.076) in the metal-on-metal hip resurfacing group. Subgroup analyses in 34 patients (17 per group), after exclusion of primary ocular pathology, showed the same trend in gray matter attenuation in the occipital cortex and basal ganglia and a smaller optic chiasm in the metal-on-metal hip resurfacing group (mean difference, -3.9 mm2; P=.048). No other structural or functional differences were found between the groups. CONCLUSIONS: Chronic exposure to metal-on-metal hip resurfacing is associated with subtle structural change in the visual pathways and the basal ganglia in asymptomatic patients.

The documentation of consent and disclosure of neurogenetic testing outside clinical genetics.

Neurogenetic tests are increasingly requested by clinical neurologists without any formal training in clinical genetics. The aim of our study was to assess the documentation of consent and disclosure of genetic test results in a large regional clinical neuroscience centre. Documentation of some form of consent was evident in only 26/132 (20 %) of tests. However, the higher proportion of both positive and negative results disclosed (50/132, 38 %) suggest that the former figure may underestimate actual rates of undocumented consent within the clinical setting. Our findings highlight the need for a review of established practices surrounding consent in clinical neurology.

Potential coeliac disease in Type 1 diabetes mellitus: does a positive antibody lead to increased complications?

BACKGROUND AND AIMS: Coeliac disease (CD) is more common in people with Type 1 diabetes and is associated with poorer glycaemic control, lipid profiles, nephropathy and retinopathy. Potential CD (positive serology but normal duodenal biopsy) is associated with neuropathy but patients with coexisting Type 1 diabetes were excluded. The aim was to determine whether potential CD is associated with increased microvascular complications in patients with Type 1 diabetes. METHODS AND RESULTS: Four groups were recruited; 1) patients with Type 1 diabetes and potential CD, 2) patients with Type 1 diabetes and newly identified CD, 3) patients with Type 1 diabetes alone and 4) patients with CD alone. Glycaemic control, quality of life, lipid profile and microvascular complication rates were examined. As many as 76 individuals were included in the study: 22 in group 1, 14 in group 2, 24 in group 3 and 16 in group 4. There were no differences in age, gender, BMI and diabetes duration between the groups. Patients in group 1 had significantly lower total cholesterol compared to group 3 (p = 0.003) but higher than group 2 (p = 0.027). There were no significant differences in HbA1c, HDL cholesterol, cholesterol:HDL ratio, creatinine, quality of life scores or prevalence of neuropathy between individuals in group 1 and the other groups. CONCLUSIONS: This is the first study to assess the effects of potential CD in patients with Type 1 diabetes. It appears that an enteropathy is required as well as antibody positivity in order to increase the risk of diabetes related complications. This pilot data requires further longitudinal validation.

Serological testing for coeliac disease in Type 1 diabetes mellitus: is immunoglobulin A level measurement necessary?

AIMS: Immunoglobulin A (IgA) measurement is advocated when case finding for coeliac disease in patients with Type 1 diabetes mellitus. Currently, there is a paucity of contemporary studies assessing IgA deficiency in Type 1 diabetes. This study evaluates the prevalence of IgA deficiency in individuals with Type 1 diabetes, compared with patients with coeliac disease and control subjects. In addition, we evaluate whether routine IgA measurement is justifiable when case finding for coeliac disease in patients with Type 1 diabetes. METHODS: All patients were assessed using IgA endomysial antibodies, IgA anti-tissue transglutaminase antibodies and total IgA levels. Altogether, 2434 individuals were tested: 1000 patients with Type 1 diabetes, 234 patients with coeliac disease and 1200 population control subjects. Definitive IgA deficiency was defined as total IgA levels < 0.07 g/l. RESULTS: The prevalence of IgA deficiency was significantly more common in patients with Type 1 diabetes (0.9%, n = 9/1000; P = 0.036) and coeliac disease (1.29%, n = 3/234; P = 0.041) when compared with population control subjects (prevalence of 0.17%, 2/1200). No statistical difference between Type 1 diabetes and coeliac disease for IgA deficiency was identified (P = 0.87). Of patients in the group with Type 1 diabetes, 3.3% (33/1000) had coeliac disease, and of those only one patient had IgA deficiency leading to an antibody-negative presentation. Both IgA-deficient individuals within the population control subjects had normal duodenal biopsies and no relevant symptoms. CONCLUSIONS: IgA deficiency is more common in Type 1 diabetes compared with population control subjects. Despite this, very few individuals with Type 1 diabetes and IgA deficiency appear to have villous atrophy on biopsy. These outcomes question the practice of routine IgA measurement when case finding for coeliac disease in patients with Type 1 diabetes.

MR spectroscopy and atrophy in Gluten, Friedreich's and SCA6 ataxias.

BACKGROUND: Previous work using proton MR spectroscopy ((1)H-MRS) of the cerebellum in the ataxias suggested that (1)H-MRS abnormalities and atrophy do not necessarily occur concurrently. AIMS: To investigate the spectroscopic features of different types of ataxias. METHODS: Using a clinical MR system operating at 1.5T, we performed (1)H-MRS with a single voxel placed over the right dentate nucleus in 22 patients with gluten ataxia (GA), six patients with Friedreich's ataxia (FA), six patients with spinocerebellar ataxia type 6 (SCA6) and 21 healthy volunteers. Atrophy of the vermis and hemispheres on standard MRI was rated by a neuroradiologist. Any interaction between atrophy and (1)H-MRS was analysed for the three groups of patients and controls. RESULTS: Patients with GA had significant atrophy of the vermis and hemispheres as well as abnormal (1)H-MRS. Patients with SCA6 had more severe overall atrophy of the vermis and hemispheres, but relatively preserved N-acetyl-aspartate/creatine (NAA/Cr). The FA group showed significant atrophy of only the superior vermis with normal (1)H-MRS. CONCLUSIONS: This study suggests that (1)H-MRS of the cerebellum in patients with ataxia provides information in addition to the presence of atrophy. There are significant (1)H-MRS differences amongst different types of ataxia with interesting correlations between atrophy and NAA/Cr.

GAD antibody-associated neurological illness and its relationship to gluten sensitivity.

BACKGROUND: The high prevalence of gluten sensitivity in patients with stiff-person syndrome (SPS) lead us to investigate the relationship between gluten sensitivity and GAD-antibody-associated diseases. METHODS: We used ELISA assays for anti-GAD and for serological markers of gluten sensitivity. Patients were recruited from clinics based at the Royal Hallamshire hospital, Sheffield, UK. Patients with gluten sensitivity were followed up after the introduction of a gluten-free diet and serological testing was repeated. RESULTS: Six of seven (86%) patients with SPS were positive for anti-GAD, mean titre 109 U/ml; This compared with 9/90 (11%) patients with idiopathic sporadic ataxia, mean titre 32 U/ml, 16/40 (40%) patients with gluten ataxia, mean titre 25 U/ml, and 6/10 patients with type 1 diabetes only, mean titre 8 U/ml. None of 32 patients with celiac disease only, and of 40 patients with genetic ataxia were positive for anti-GAD. The titre of anti-GAD reduced following the introduction of a gluten-free diet in patients with SPS who had serological evidence of gluten sensitivity. The same was observed in patients with gluten ataxia and anti-GAD antibodies. This was also associated with clinical improvement. CONCLUSION: These findings suggest a link between gluten sensitivity and GAD antibody-associated diseases.

Atopic patients with genital warts have a more protracted clinical course and a greater probability of recurrences.

The factors predicting an unfavourable response of genital warts to treatment have not been determined. The disease characteristics were recorded for 390 patients with genital warts and treated by cryotherapy. The time to achieve clearance was recorded. A personal and family history of asthma, hay fever or eczema, as well as a personal history of common warts and number of recurrences was obtained by telephone four to five years after the clinical visits. In multiple regression analysis, the number of lesions (P < 0.001), extent of the disease (P = 0.003) and personal history of atopy (P = 0.001) were found to influence the time until response to treatment. Similar results were obtained for family history of atopy. The number of sexual partners (P = 0.007), extent of the disease (P = 0.009) and personal history of atopy (P < 0.001) were the main factors influencing the probability of recurrence in multiple logistic regression. The results for family history of atopy were again similar. The study concludes that atopy is a major factor influencing the time frame of the therapeutic response and the probability of recurrence in patients with genital warts.