Diabetes mellitus type 1

Disease class: Autoimmune diseases

Disease class: Diabetes mellitus  

Also known as insulin-dependent diabetes mellitus (IDDM).

Signs

• Age: usually young
• Body type: usually thin

 

Pathophysiology

There is autoimmune-mediated destruction of pancreatic beta cells.
As the population of functional beta cells falls, insulin production declines.
As insulin levels fall, serum glucose levels rise.
The cells of the body will respond to insulin as normal, so administration of an appropriate amount of insulin would completely correct any hyperglycaemia.

 

Complications

• Diabetic ketoacidosis: Type 1 diabetics often have little to no endogenous insulin. They can forget or neglect to administer their exogenous insulin, and as their cells deplete their glucose supplies, they progress towards lipolysis. An acute illness may trigger more rapid energy consumption (by lipolysis) and consequently trigger DKA. 
• The usual complications of chronic diabetes mellitus.

 

Investigations

• Pancreatic islet cell antibodies
• Anti-GAD
   

 

Management

Unfortunately, exogenous insulin is administered by injection, and serum glucose is measured from a blood sample. It is impractical to constantly add small amounts of insulin and constantly measure the levels of glucose. This means that insulin therapy cannot control serum glucose as tightly as beta cells.

Treatment should aim to minimise the progression of known complications.

Adolescents and young adults are infamous for being likely to show poor compliance with treatment. This can quickly cause significant irreversible damage throughout the body.