Pediatric GAD-65 Autoimmune Encephalitis: Assessing Clinical Characteristics and Response to Therapy With a Novel Assessment Scale.

BACKGROUND: Glutamic acid decarboxylase (GAD) encephalitis is a neuroinflammatory disease characterized by a broad range of symptoms including cognitive deficits, behavioral changes, and seizures. Children with this disorder have heterogeneous presentations, and little is known about symptom progression over time and response to immunotherapy. METHODS: This study reports 10 pediatric GAD encephalitis cases and symptoms found at presentation and follow-up. In addition, symptom severity was reported utilizing a novel scale evaluating functional outcomes across the domains affected by autoimmune encephalitis including cognition, language, seizures, psychiatric symptoms, sleep, and movement. Retrospective chart review was conducted for 10 patients aged <18 years, diagnosed with GAD encephalitis, and followed for one year or more. Chart review included clinical, imaging, and laboratory findings at time of diagnosis and at six- and 12-month follow-ups. RESULTS: At presentation, cognitive deficits were found in all patients, seizures in six of 10, and language decline in seven of 10. Psychiatric symptoms were prominent for all but one patient with three of nine patients presenting with psychosis. Fatigue, sleep disruption, and movement disorders were less prominent symptoms, occurring in approximately half of the cohort. Cognition and fatigue improved significantly over time when compared with symptom severity, whereas seizures, psychiatric symptoms, and sleep did not. Language and sleep showed improvement only in early stages. Analysis of seizure frequency and type noted variability mirroring trends noted in adult studies of GAD encephalitis. CONCLUSIONS: This study demonstrated the variability of symptom profiles of pediatric GAD encephalitis and benefits of symptom severity scales. Symptom profiles and progression vary in this population.

Latent Autoimmune Diabetes in Adults in North Indian Region: Assessment of ß-Cell Function, Metabolic and Immunological Features.

BACKGROUND: We undertook a study to assess ß-cell function, metabolic and immunological features of patients with latent autoimmune diabetes in adults (LADA) and investigate heterogeneity within LADA based on low and high glutamic acid decarboxylase autoantibodies (GADA) titers. METHODS: A total of 139 patients with adult-onset diabetes were examined cross-sectionally in the National capital region of Northern India. Medical history of all subjects was reviewed with the aim of collecting clinical data. Glucose, glycosylated hemoglobin, lipid profile, creatinine, C-peptide, and GADA were measured in 10-12 hrs fasting blood sample. RESULTS: Assessment of metabolic features revealed lower mean systolic blood pressure in subjects with LADA than in those with type 2 diabetes (DM2). Mean triglyceride levels were lower in LADA subjects compared to DM2 subjects. Compared to DM2 subjects, prevalence of metabolic syndrome (MS) was also lower in LADA subjects. Compared to GADA-low, all GADA-high patients were male, had lower waist circumference, fasting C-peptide (FCP), and prevalence of MS. Compared to DM2 patients, GADA-high patients were younger, had lower age at onset, body mass index, waist circumference, systolic blood pressure, triglycerides, FCP, and prevalence of MS. The rate of patients on insulin was higher in GADA-high compared to DM2. There were no significant differences between characteristics of DM2 and GADA-low patients. CONCLUSIONS: Our results indicate that LADA patients have distinct metabolic features with lower residual ß-cell function than DM2 patients. GADA titer is important parameter in defining the severity of the disease as patients with high GADA titer tend to have significant ß-cell impairment.

Assessment of the effects of glutamic acid decarboxylase antibodies and trace elements on cognitive performance in older adults.

BACKGROUND: Homeostatic imbalance of trace elements such as iron (Fe), copper (Cu), and zinc (Zn) demonstrated adverse effects on brain function among older adults. OBJECTIVE: The present study aimed to investigate the effects of trace elements and the presence of anti-glutamic acid decarboxylase antibodies (GADAs) in human cognitive abilities among healthy older adults. METHODS: A total of 100 healthy subjects (65 males, 35 females; age range; 64-96 years) were recruited for this study. Based on Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) score, the participants were classified according to cognitive performance into normal (n=45), moderate (n=30), and severe (n=25). Cognitive functioning, leisure-time physical activity (LTPA), serum trace elements - Fe, Cu, Zn, Zn/Cu, and GADAs were assessed using LOTCA battery, pre-validated physical activity (PA) questionnaire, atomic absorption, and immunoassay techniques, respectively. RESULTS: Approximately 45% of the study population (n=45) had normal distribution of cognitive function and 55% of the study population (n=55) had abnormal cognitive function; they were classified into moderate (score 62-92) and severe (score 31-62). There was a significant reduction in the level of Zn and Zn/Cu ratio along with an increase in the level of Fe, Cu, and anti-GADAs in subjects of severe (P=0.01) and moderate (P=0.01) cognitive performance. LOTCA-cognitive scores correlated positively with sex, HbA(1c), Fe, Cu, Zn, and Zn/Cu ratio, and negatively with age, PA, body mass index, and anti-GADAs. Significant inter-correlation was reported between serum trace element concentrations and anti-GADAs which suggest producing a cognitive decline via oxidative and neural damage mechanism. CONCLUSION: This study found significant associations among trace elements, anti-GADAs, and cognitive function in older adults. The homeostatic balance of trace elements should be recommended among older adults for better cognitive performance.

Antineuronal antibodies and infectious pathogens in severe acute pediatric encephalitis.

The pathogenesis of acute encephalitis is divided into either direct infection or by immune-mediated inflammation, but the cause is still unknown. This retrospective study aimed to screen antineuronal antibodies in children with severe acute encephalitis. Thirty-four children (22 boys and 12 girls) underwent assessments such as antineuronal antibodies survey for autoimmune encephalitis and polymerase chain reaction/viral culture and antibody assays for all commonly recognized causes of infectious encephalitis. Sixteen (47.1%) were positive for autoantibodies, including antiglutamic acid decarboxylase antibodies in 16 and voltage-gated potassium channel complex antibodies in 1. Sixteen patients (47.1%) had presumed infectious etiologies, including 6 with influenza, 6 with Mycoplasma pneumoniae, 3 with enterovirus, and 1 with herpes simplex virus. In this study, influenza and Mycoplasma pneumoniae infection are the main presumed causes of severe acute encephalitis in children, although an immune-mediated mechanism may also play a role.

Screening for insulinoma antigen 2 and zinc transporter 8 autoantibodies: a cost-effective and age-independent strategy to identify rapid progressors to clinical onset among relatives of type 1 diabetic patients.

In first-degree relatives of type 1 diabetic patients, we investigated whether diabetes risk assessment solely based on insulinoma antigen 2 (IA-2) and zinc transporter 8 (ZnT8) antibody status (IA-2A, respectively, ZnT8A) is as effective as screening for three or four autoantibodies [antibodies against insulin (IAA), glutamate decarboxylase 65 kDa (GAD) glutamate decarboxylase autoantibodies (GADA) and IA-2A with or without ZnT8A] in identifying children, adolescents and adults who progress rapidly to diabetes (within 5 years). Antibodies were determined by radiobinding assays during follow-up of 6444 siblings and offspring aged 0-39 years at inclusion and recruited consecutively by the Belgian Diabetes Registry. We identified 394 persistently IAA(+) , GADA(+) , IA-2A(+) and/or ZnT8A(+) relatives (6·1%). After a median follow-up time of 52 months, 132 relatives developed type 1 diabetes. In each age category tested (0-9, 10-19 and 20-39 years) progression to diabetes was significantly quicker in the presence of IA-2A and/or ZnT8A than in their joint absence (P < 0·001). Progression rate was age-independent in IA-2A(+) and/or ZnT8A(+) relatives but decreased with age if only GADA and/or IAA were present (P = 0·008). In the age group mainly considered for immune interventions until now (10-39 years), screening for IA-2A and ZnT8A alone identified 78% of the rapid progressors (versus 75% if positive for ≥ 2 antibodies among IAA, GADA, IA-2A and ZnT8A or versus 62% without testing for ZnT8A). Screening for IA-2A and ZnT8A alone allows identification of the majority of rapidly progressing prediabetic siblings and offspring regardless of age and is more cost-effective to select participants for intervention trials than conventional screening.

LIPS islet autoantibody assays in high-throughput format for DASP 2010.

BACKGROUND: For cost-effective population-based diabetes prediction and confirmation, islet autoantibody assays must be made more economical. METHODS: We evaluated glutamic acid decarboxylase (GAD)-Ruc (renilla luciferase) and IA2ic (also known as ICA512ic)-Ruc (renilla luciferase) fusion protein constructs in high-throughput islet antibody assay formats. RESULTS: Antigen production via transfection onto COS cells in 100 mm culture dishes yielded sufficient antigen to assay 375 and 535 serum samples for GAD and IA2ic per dish, respectively. Antigen was usably stable after -80 °C storage for 40-80 days after which luciferase activity decreased. The mean signal-to-noise ratios for luciferase-based immunoprecitation system (LIPS) GAD and LIPS IA2ic were 88±24 and 219±89, respectively, comparing favourably to radio-binding assays (RBA) in the same format. However, the coefficient of variation among triplicate wells was higher for IA2ic than for GAD in LIPS, similar to findings in RBA format. Correlation coefficients between autoantibody indices determined from the RBA and LIPS methods were only R2=0.79 and R2=0.75 for GAD and IA2ic, respectively, raising the possibility that different epitopes were favoured in the two different assay formats. Nevertheless, overall concordance for the two assay types was high, at 228/240=95.0% for GAD and 494/521=94.8% for IA2ic. Using optimal cutoffs, Diabetes Autoantibody Standardization Program (DASP) 2010 sensitivity/specificity was 80/99% for GAD RBA, 80/99% for GAD LIPS, 70/98% for IA2 RBA, and 72/99% for IA2 LIPS. CONCLUSION: The LIPS assays for islet autoantibodies to GAD and IA2ic performed as well as RBA in DASP 2010. With further refinements in expression and storage, these assays may be more economical than current methods to measure islet autoantibodies in type 1 diabetes.

[Pancreatic function assessment in type 1 diabetes mellitus patients according to disease duration]. / Avaliação da função pancreática em pacientes com diabetes melito tipo 1 de acordo com a duração da doença.

UNLABELLED: Patients with type 1 diabetes (T1D) may exhibit some residual insulin secretion for many years after their diagnosis. This has been associated with a more favorable prognosis. OBJECTIVE: To analyze insulin secretion in individuals with T1D using C-peptide (CP) response to glucagon and comparing patients with recent onset (<5 years - Group 1) and long-standing disease (>5 years -Group 2). METHODS: Subjects with T1D had their blood sampled before (fasting) and 6 minutes after glucagon infusion for CP, HbA1c and anti-GAD measurement. RESULTS: Forty-three individuals were evaluated, 22 in Group 1 and 21 in Group 2. Preserved insulin secretion (CP >1.5 ng/mL) was observed in 6 (13.9%) and in 8 (18.6%) patients before (CP 1) and after (CP 2) glucagon stimulus, respectively, showing no difference between the groups (p=0.18 and 0.24). CP 1 and CP 2 were detectable (>0.5 ng/dL) in 13 (30.2%) and 18 (41.9%) patients, respectively. Both were more frequent in Group 1 than in Group 2 (p=0.45 for CP1/p=0.001 for CP 2). Similar serum levels where seen between the groups, both before and after stimulus (1.4+/-0.8 vs. 1.2+/-1.0; p=0.69 and 1.8+/-1.5 vs. 1.7+/-0.8; p=0.91). Group 1 presented an inverse correlation between disease duration and CP 2 (R=-0.58; p=0.025). CONCLUSION: A significant number of patients with T1D have detectable residual insulin secretion, especially in the first 5 years of disease. These subjects are an ideal population for clinical trials that target the prevention of beta cell function loss in T1D.

Avaliação da função pancreática em pacientes com diabetes melito tipo 1 de acordo com a duração da doença / Pancreatic function assessment in type 1 diabetes mellitus patients according to disease duration

Os pacientes com diabetes melito tipo 1 (DM1) podem apresentar secreção residual de insulina por longos períodos, o que tem sido associado a prognóstico mais favorável. OBJETIVO: Avaliar a secreção de insulina por meio da dosagem de peptídeo C (PC) em pacientes com DM1 de curta (<5 anos; grupo 1) e longa (> 5 anos; grupo 2) duração da doença. PACIENTES E MÉTODOS: Voluntários com DM1 coletaram sangue em jejum e 6 minutos após a infusão de glucagon para dosagem de PC, HbA1c e anti-GAD. RESULTADOS: Foram avaliados 43 pacientes, 22 no grupo 1 e 21 no grupo 2. Secreção de insulina preservada (PC > 1,5 ng/mL) foi identificada em seis (13,9 por cento) e oito (18,6 por cento) casos nas coletas basal (PC1) e após estímulo (PC2), sem diferença entre os grupos (p = 0,18 e 0,24). PC1 foi detectável (> 0,5 ng/mL) em 13 (30,2 por cento) e PC2 em 18 (41,9 por cento) casos, mais frequentes no grupo 1 do que no 2 (p = 0,045 para PC1/p = 0,001 para PC2). Os títulos de PC1 (1,4 ±0,8 versus 1,2 ±1,0; p = 0,69) ou PC2 (1,8 ±1,5 versus 1,7 ±0,8; p = 0,91) não diferiram entre os grupos. No grupo 1 houve correlação inversa entre tempo de doença e PC2 (R = -0,58; p = 0,025). CONCLUSÃO: Uma proporção significativa dos pacientes com DM1 apresenta secreção residual de insulina, especialmente nos primeiros cinco anos da doença. Tais indivíduos representam a população ideal para estudos visando à prevenção secundária da doença.

Patients with type 1 diabetes (T1D) may exhibit some residual insulin secretion for many years after their diagnosis. This has been associated with a more favorable prognosis. OBJECTIVE: To analyze insulin secretion in individuals with T1D using C-peptide (CP) response to glucagon and comparing patients with recent onset (<5 years - Group 1) and long-standing disease (>5 years -Group 2). METHODS: Subjects with T1D had their blood sampled before (fasting) and 6 minutes after glucagon infusion for CP, HbA1c and anti-GAD measurement. RESULTS: Forty-three individuals were evaluated, 22 in Group 1 and 21 in Group 2. Preserved insulin secretion (CP >1.5 ng/mL) was observed in 6 (13.9 percent) and in 8 (18.6 percent) patients before (CP 1) and after (CP 2) glucagon stimulus, respectively, showing no difference between the groups (p=0.18 and 0.24). CP 1 and CP 2 were detectable (>0.5 ng/dL) in 13 (30.2 percent) and 18 (41.9 percent) patients, respectively. Both were more frequent in Group 1 than in Group 2 (p=0.45 for CP1/p=0.001 for CP 2). Similar serum levels where seen between the groups, both before and after stimulus (1.4±0.8 vs. 1.2±1.0; p=0.69 and 1.8±1.5 vs. 1.7±0.8; p=0.91). Group 1 presented an inverse correlation between disease duration and CP 2 (R=-0.58; p=0.025). CONCLUSION: A significant number of patients with T1D have detectable residual insulin secretion, especially in the first 5 years of disease. These subjects are an ideal population for clinical trials that target the prevention of â cell function loss in T1D.

Retrospective assessment of islet cell autoantibodies in pancreas organ donors.

OBJECTIVE: Of deceased pancreas donors, 3-4% may have autoantibodies (AAb) to pancreatic islet cell antigens; these autoantibodies are well-established markers of type 1 diabetes. We investigated whether donor AAb positivity could affect the outcome of pancreas transplantation. RESEARCH DESIGN AND METHODS: We retrospectively tested AAb in 135 donors whose pancreata and kidneys were transplanted in type 1 diabetes patients. We measured AAb to glutamic acid decarboxylase (GAD-AAb), the tyrosine-phosphatase-like protein IA2 (IA2-AAb), and insulin (insulin-AAb). We then evaluated pancreas transplant outcome data. RESULTS: Four of 135 (2.96%) donors were AAb positive: three donors had GAD-AAb, and one donor had insulin-AAb. Their respective recipients became insulin independent on follow-up. Three of the four recipients had normal, insulin-producing grafts 3-5.8 years after transplant. The recipient of the insulin-AAb-positive donor pancreas developed chronic rejection following discontinuation of immunosuppression 3.3 years after transplant. CONCLUSIONS: Single AAb positivity did not affect the outcome of pancreas transplantation in our study.

A neuropsychological assessment of phobias in patients with stiff person syndrome.

A neuropsychological assessment was performed in 10 patients with stiff person syndrome (SPS) to determine whether their anxiety and phobic symptoms precede stiffness and spasms or represent a reaction to disability. No neurocognitive dysfunction was noted. Patients perceived fears and anxiety as realistic and caused by SPS rather than due to an inherent phobic neurosis.

IA-2 antibody prevalence and risk assessment of early insulin requirement in subjects presenting with type 2 diabetes (UKPDS 71).

AIMS/HYPOTHESIS: Established autoimmune markers of type 1 diabetes, including islet cell autoantibodies (ICA) and autoantibodies to glutamic acid decarboxylase (GADA) have been used to screen people presenting with type 2 diabetes for latent autoimmune diabetes in adults. We have examined the prevalence of autoantibodies to protein tyrosine phosphatase isoforms IA-2 (IA-2A) and IA-2beta/phogrin (IA-2betaA) in a cohort of adult UKPDS patients thought to have type 2 diabetes, and investigated the possible role of these autoantibodies in predicting requirement for insulin therapy. METHODS: IA-2A and IA-2betaA were measured by a validated radioimmunoassay with human recombinant autoantigens in 4,169 white Caucasian patients aged 25-65 years and newly diagnosed with type 2 diabetes. The clinical requirement for insulin therapy within 6 years was examined in 2,556 patients not randomised to insulin. RESULTS: IA-2A and IA-2betaA were present in 2.2 and 1.4%, respectively, of these patients. IA-2A were more prevalent in younger patients (p for trend <0.00001), more often associated with the HLA-DR4 allele (26.3 vs 8.0%, p<0.0001), and their presence increased the likelihood of insulin therapy requirement within 6 years from diagnosis [relative risk (95%CI) 12.2 (9.8-15.3)]. The presence of IA-2A together with GADA increased the relative risk of requiring insulin therapy from 5.4 (4.1-7.1) for GADA alone to 8.3 (3.7-18.8) and the corresponding positive predictive value from 33 to 50%. CONCLUSIONS/INTERPRETATION: In type 2 diabetes, the presence of IA-2A is infrequent, associated with the HLA-DR4 haplotype, and highly predictive of future need for insulin therapy. The measurement of IA-2betaA does not provide additional information.

Combined measurement of diabetes mellitus immunological markers: an assessment of its benefits in adult-onset patients.

The convenience of combining the measurement of antibodies to glutamic acid decarboxylase (GADA), protein tyrosine phosphatase (IA-2A), and autoantibodies to insulin (IAA) in diabetic patients was assessed. We analysed 71 type 1 and 115 adult-onset diabetic patients. The latter were grouped into three categories according to the time of evolution to insulin dependence. The main findings were as follows: (i) in type 1 diabetes, the combined analysis of GADA and IA-2A showed a sensitivity of 87.4% and was not appreciably improved by adding IAA; (ii) out of 31 adults who required insulin immediately or within the first two years of diagnosis, 41.9, 29.0, and 6.5% were positive for at least one, two or all three, and all three markers, respectively; GADA was the most prevalent (35.5%) and IA-2A the least represented (16.1%); (iii) 34 adult patients with slow evolution to insulin dependence showed a completely different profile: 5.9% were GADA positive and 23.5% were IAA positive and no double or triple positivity was observed as all patients were IA-2A negative; and (iv) 50 type 2 patients who had not required insulin treatment showed a low incidence of GADA (4%) as the only marker present. We conclude that a combined double-antigen test for GADA and IA-2A is a useful strategy for prospective screening of type 1 diabetes. However, in adults, the profile of individual markers discloses the course to insulin dependence. Therefore, it seems advisable to measure the markers separately, to allow a better classification of these patients, and help define their treatment.

A novel high-throughput method for accurate, rapid, and economical measurement of multiple type 1 diabetes autoantibodies.

Prediction of Type 1 diabetes for study of preventive therapies requires screening the general population, where 85% of new cases occur. Even with HLA-based prescreening, nearly 20% of all children will need multiple serum autoantibody testings. High-throughput, economical, and accurate methods are therefore essential. We have developed such a radiobinding method, using 96-well microtiter plates and a novel immune complex capture method via membrane-bound Protein A. Each microtiter plate contained a standard negative control serum, and low-, medium-, and high-level positive control sera. All sera were evaluated in triplicate. This readily allowed quality control criteria both for triplicates of individual sera and for each 96-well plate. Inter-assay coefficients of variation (CVs) were all

Optimized autoantibody-based risk assessment in family members. Implications for future intervention trials.

OBJECTIVE: To determine the best autoantibody-based testing strategy for recruiting relatives for future intervention trials and to establish the role of islet cell antibodies (ICAs) within this strategy. RESEARCH DESIGN AND METHODS: ICAs, insulin autoantibodies (IAAs), GAD antibodies, and IA-2 antibodies were determined in serum samples at study entry of 3,655 non-diabetic first-degree relatives of patients with type 1 diabetes who were followed for a median of 5.5 years. The cumulative risk of diabetes associated with single and combined antibody marker levels of > or = 97.5th percentile in schoolchildren was calculated by using life-table analysis. RESULTS: Of the 26 relatives who developed insulin-requiring diabetes during follow-up, 16 were aged < 20 years and 7 were aged 20-39 years at study entry. Of the 23 cases aged < 40 years, 83% had IA-2 and/or GAD antibodies, and 87% had IAA and/or GAD antibodies > or = 97.5th percentile compared with 61% who had ICAs of > or = 5 Juvenile Diabetes Foundation units (JDF U). A two-step strategy with parallel testing for IA-2/GAD antibodies followed by IAA testing identified 50% of cases aged < 20 years and was associated with a 71% risk within 10 years. In subjects aged 20-39 years, this strategy conferred a 51% risk, whereas using ICAs as the second test gave 86% sensitivity and a 74% risk. Primary screening for IA-2 and/or GAD antibodies followed by testing for IAA and/or ICA antibodies achieved the highest sensitivity in both age-groups and conferred a 63% risk. In contrast, ICAs of > or = 20 JDF U (the inclusion criteria for the European Nicotinamide Diabetes Intervention Trial) gave 48% sensitivity and 35% risk. CONCLUSIONS: ICA testing can be replaced as a primary screening measure by IA-2/GAD or IAA/GAD antibody testing. The sensitivity of ICAs (used alone or in combination with IAAs) gives them a useful role in second-line testing. Combination testing could reduce the size of screening populations needed for recruitment in future intervention trials by approximately 50% compared with testing based on ICAs alone.

[A cost analysis of diagnostic screening for the differentiation of type-1 and type-2 diabetics aged 30 to 45. A health economics modelling calculation]. / Kostenanalyse eines Diagnostik-Screenings zur Differenzierung von Typ-1- und Typ-2-Diabetikern im Alter von 30 bis 45 Jahren. Gesundheitsökonomische Modellrechnung.

BACKGROUND AND OBJECTIVE: Because of its chronic course and increasing incidence diabetes mellitus is assuming increasing importance not only for medical reasons but also on health policy. Early recognition of carriers of autoantibodies among type 2 diabetics (noninsulin-dependent; NIDDM) and the resulting optimization of blood glucose could lead to a reduction of secondary diseases. A health-economic model for calculating costs was used to test the socioeconomic significance of a screening programme for identifying carriers of antibodies against glutamic acid decarboxylase among NIDDM diabetics. PATIENTS AND METHODS: Health-economic analysis was based on the incidence of positive autoantibody tests among diabetics aged between 30 and 45 years. Results for a cohort of diabetics who had been screened were compared with those obtained in a control group without screening. A time-span of 20 years was chosen because of the late manifestations of diseases secondary to DM. The model calculations used a cost analysis. Data were based on interventional clinical and epidemiological studies. Cost of treatment of secondary diseases was confined to a one-year period. In the first instance the direct medical costs and additionally the indirect economic costs, generated by patients' loss of production and disability to work were calculated. One-dimensional sensitivity analysis was used to check the assumptions underlying the model. RESULTS: Per patient in the model, total costs of the screening programme over a period of 20 years were calculated at DM 31,278, of which DM 7,799 were direct and DM 23,479 indirect costs. The calculated costs for the control subjects (no screening) were DM 35,290, of which DM 10,984 were direct and DM 24,306 indirect costs. CONCLUSIONS: Extrapolating to the entire population, with an investment by the statutory health insurance of ca. DM 22.8 million, employing a full screening programme would lead to a saving of DM 2.6 billion.