Influence of age on clinical and immunological characteristics of newly diagnosed type 1 diabetic patients

Predictors of the clinical severity of T1DM presentation at diagnosis in children and adolescents with type 1 diabetes mellitus (T1DM)

PURPOSE

We aimed to assess factors associated with the presence and severity of ketoacidosis (DKA) at pediatric type 1 diabetes (T1DM) diagnosis, in relation to pancreatic, associated and familial autoimmunity.

METHODS

Antibodies against pancreatic beta-cells, organ specific autoantibodies (thyroid, celiac, and parietal) and family history of autoimmunity were retrospectively evaluated in 116 T1DM patients aged 11.9 ± 4.6 (mean ± SD) years, with disease duration 7.62 ± 3.67 years (mean ± SD).

RESULTS

Most patients (67.2%) presented with DKA at diagnosis. Younger children (< 2 years) had tenfold risk of DKA, compared to older children (12.1-15 years) (OR = 10.8, 95% CI: 1.0-116.9, P = 0.05). Fasting c-peptide levels were lower in the DKA group (OR = 0.26, 95% CI = 0.07-0.89, P = 0.033). The number of anti-pancreatic antibodies at disease onset did not show any significant correlations with the presence (p = 0.889) or severity of DKA (p = 0.863). All patients with multiple autoimmunity (> 2 autoimmune diseases plus T1DM) presented with DKA. Familial autoimmunity acted protectively against DKA manifestation (OR = 0.40, 95% CI = 0.16-1.0, P = 0.051).

CONCLUSIONS

Among newly diagnosed T1DM patients, 67.2% presented with DKA. Younger age, lower c-peptide and the presence of associated autoimmunity were predictive factors of the presence and severity of DKA at diagnosis. High degree of suspicion, due to family history, may prevent DKA development and severity.

The prevalence and risk factors for coeliac disease among children and adolescents with type 1 diabetes mellitus

AIMS

Our aim was to determine in children with T1DM the prevalence of positive antibodies against tissue transglutaminase (anti-tTG IgA) as indices of coeliac disease (CD), as well as its clinical presentation, its determinants and its association with thyroid (anti-TG, anti-TPO) and pancreatic b-cell autoimmunity (anti-GAD).

METHODS

The study included 105 children and adolescents with T1DM, aged (mean±SD) 12.44±4.76 years, with a T1DM duration of 4.41±3.70 years.

RESULTS

Fifty of our patients (47.6%) were positive for anti-GAD, 9/105 (8.6%) for anti-tTG IgA and 21/105(20%) for anti-thyroid antibodies. The anti-tTG IgA (+) children, in comparison with the rest of the study population, were of younger age (9.31 vs. 12.74 years, p=0.038), shorter diabetes duration (2.16 vs. 4.62 years, p=0.056) and had mild growth impairment (height SDS: -0.55 vs. +0.20, p=0.055). Univariate logistic regression analysis revealed that the presence of anti-tTG IgA (+) was associated with younger age and shorter T1DM duration. Only 5/9 (55.6%) children with high titres of anti-tTG IgA developed mild gastrointestinal symptoms or growth retardation and had histological findings typical of CD.

CONCLUSIONS

The prevalence of anti-tTG IgA positivity among T1DM children was 8.6% and its occurrence was associated with younger age and short diabetes duration. Since CD presents in T1DM patients asymptomatically or with non-specific symptoms, periodic autoantibody screening is necessary for its early diagnosis.

Autoimmune thyroid disease in patients with anti-GAD positive type 1 diabetes mellitus

The aim of the study was to determine the frequency and titers of anti-thyroid peroxidase (Anti-TPO), anti-thyroglobulin (Anti-TG), and anti-glutamic acid decarboxylase (Anti-GAD) antibodies in Turkish patients with type 1 diabetes mellitus (DM), and to compare the frequency of anti-TPO and anti-TG titers in the presence or absence of anti-GAD. A total of 104 patients including 56 males and 48 females with type 1 DM and their age-, gender-, and body mass index-matched control group, including 31 males and 27 females, 58 cases in total with an age range of 15-50 years, were recruited into this study. In patients with type 1 DM, positive anti-GAD was detected in 30.8% (n=32). In patients with positive anti-GAD, rate of positive anti-TPO was 37.5%; however, in patients with negative anti-GAD, the rate of positive anti-TPO was 9.7% and the difference was statistically significant (p=0.001). In patients with positive anti-GAD, the rate of positive anti-TG was 18.8%. In patients with negative anti-GAD, the rate of positive anti-TG was 2.8%, and the difference between them was statistically significant (p=0.005). In patients with positive and negative anti-GAD, rates of both positive anti-TPO and anti-TG were 15.6% and 1.4%, respectively, with the difference showing statistical significance (p=0.004). Thyroid autoimmunity in type 1 DM patients with positive anti-GAD was apparently higher; therefore, these patients should be followed more frequently and carefully.

Islet cell autoantibodies in African patients with Type 1 and Type 2 diabetes in Dar es Salaam Tanzania: a cross sectional study

Background

The aim of the present study was to assess the occurrence of glutamic acid decarboxylase autoantibodies (GADA) and insulinoma antigen 2 autoantibodies (IA2A) among patients of African origin in Dar es Salaam, Tanzania and to compare the occurrence of autoimmune mediated Type 1 diabetes with findings previously reported from the same place and from other African diabetic populations.

Methods

Two hundred and forty five patients from the diabetic clinic at Muhimbili Hospital were recruited for a cross sectional study. Patients were clinically classified into groups with Type 1 (T1D) and Type 2 diabetes (T2D); there were 94 patients with T1D and 151 with T2D. Autoantibodies for GAD and IA2 were measured with an assay based on radioligand binding. Fasting and random blood glucose, HbA1c, and C-peptide levels were also determined.

Results

Of the patients with T1D, 28 (29.8%) were GADA positive and 20 (21.3%) were IA2A positive. The overall occurrence of any autoantibody was 42.6%. The GAD and IA2 autoantibodies were detected more frequently among patients with T1D than among patients with T2D (P < 0.001). A higher autoantibody prevalence was observed with combined GADA and IA2A measurements compared to individual autoantibody measurements; 40 (42.6%) patients with T1D versus 11 (7.3%) with T2D had at least one positive autoantibody titer. There was no correlation between duration of disease and detection of autoantibodies in patients with T1D. There was a strong association with family history of diabetes among the autoantibody positive versus autoantibody negative patients with T1D (p < 0.01).

Conclusion

The prevalence of GAD and IA2 autoantibodies among African patients with T1D in Dar es Salaam was the same as that reported previously for South Africa and Ethiopia. It was much higher than the prevalence of islet cell autoantibodies (ICA) reported from the same clinic about 15 years ago. For unknown reasons the prevalence of pancreatic related autoantibodies in this African population is lower than the prevalence found among Caucasian populations.