Determination of anti-insulin and anti-glutamic acid decarboxylase in type 1 diabetic patients and their siblings in Gaza Strip

Abstract:

 Several autoantibodies are associated with autoimmune type 1 diabetes. Measurements of islet autoantibodies can assist in the diagnosis of this disease, and the detection of islet autoantibodies in nondiabetic individuals indicates a significantly increased risk for the subsequent development of type 1 diabetes. When preventive therapies for type 1 diabetes become available, islet autoantibody screening of the general pediatric population should be considered to identify individuals at risk.

The goal of this study was to address two key questions concerning autoimmune type 1 diabetes: First: What are the prevalences of anti-insulin and anti-GAD autoantibodies in patients of type 1 diabetes mellitus and their siblings in Gaza Strip? and Second: Which of the siblings are at increased risk for developing type 1 diabetes? For this purpose, 47 type 1 diabetic patients and 154 of their siblings were examined for anti-GAD and anti-insulin autoantibodies. Our results indicated that there was a significant difference between type 1 diabetic patients and controls in relation to the positivity of anti-GAD [76.6% for the patients versus 2.6% for the controls; p = 0.001] and anti-insulin autoantibodies [89.4% for the patients versus 5.2% for the controls; p = 0.001].

In addition there was a significant difference between the siblings tested in this study and the controls according to the positivity of anti-GAD [45.5% for the siblings versus 2.6% for the controls; P = 0.001] and anti-insulin autoantibodies [38.3% for the siblings versus 5.2% for the controls; P = 0.001].

A total of 27 out of 154 (17.5%) of the siblings were found to be positive for both autoantibodies, anti-GAD and anti-insulin. So such siblings may be at increased risk of developing type 1 diabetes, they must be followed up by continuous medical examination and laboratory investigation which include testing for other islet autoantibodies and HLA typing to determine whether or not they have the susceptibility alleles for type 1 diabetes.