T1 Diabetes

Type 1 Diabetes is an autoimmune disease where the B cells are attacked, so no insulin is produced.  This causes blood glucose levels to rise, resulting in hyperglycaemia.

Children are born with a genetic predisposition to the disease.  An environmental trigger causes a child with a genetic predisposition to develop the disease.

• Children with type 1 diabetes have a lack of insulin.  Insulin lowers blood glucose levels by allowing glucose into the cells.  Since the glucose cannot enter the cells and stays in the blood, this causes hyperglycaemia.
• Lymphocytes and macrophages infiltrate the Islets of Langerhans, resulting in inflammation and the destruction of B cells, which are responsible for the release of insulin into the blood.
• Autoantigens are released onto the surface of pancreatic islet cells and circulate into the bloodstream.  These are ingested by Th1 Cells.
• Th1 cells then secrete interleukin which will activate antigen-specific T cells which attack the B cells through secretion of toxic perforins and granzymes.
• Th1/2 cells also secrete interferon which activates macrophages and stimulates the release of inflammatory cytokines.
• High glucose concentration from the blood spills over into the urine, this is known as glucosuria.  When the glucose is released into the urine, it brings water with it (polyuria).  This can lead to dehydration.
• As the cells can't use the glucose for energy due to lack of insulin, they metabolise fats causing weight loss.
• Diabetic ketoacidosis is a life-threatening form of dehydration and acidosis which occurs when a non-diagnosed T1 diabetic becomes unwell.

• Risk of Long Term Complications - Complications such as retinopahty, renal failure, cardiovascular disease and neuropathy.

Initially present with a 3-week history of:

• Excessive thirst - Due to urine being released by the kidneys alongside glucose this causes dehydration and excessive thirst.
• Tiredness - As glucose cannot enter the cells this causes fatigue as the body is preserving energy.
• Frequent Urination - Body releases glucose through the urine, resulting in frequent urination.
• Weight Loss - Since glucose cannot enter the cells due to lack of insulin, stored fats are used for energy instead.  This causes noticable weight loss over a short period of time.

• Hospitalised - Newly diagnosed children are hospitalised to correct dehydration and start on insulin.
• Insulin injection - Subcutaneous injection which can either be given a set amount of times or though basal-bolus regime where longer-acting insulin keeps blood glucose levels stable through periods of fasting and separate injections of shorter-acting insulin are given to prevent blood glucose rise resulting form meals.
• CSSI (Continuous Subcutaneous Insulin Infusion) - Provics better insulin control by mimicking when glucose is released into the body in a person without diabetes.  A small pump in the arm gives a continuous dose through a tube under the skin.