Type 1 diabetes mellitus is a metabolic disorder characterised by hyperglycaemia due to absolute insulin deficiency.
Patients most often present with a few days or weeks of polyuria, polydipsia, weight loss, and weakness.
Some patients may present with diabetic ketoacidosis.
Intensive glycaemic control has been shown to decrease the incidence of microvascular and macrovascular complications.
Microvascular complications include retinopathy, nephropathy, and neuropathy.
Macrovascular complications include coronary artery, cerebrovascular, and peripheral vascular disease.
Type 1 diabetes mellitus is a metabolic disorder characterised by hyperglycaemia due to absolute insulin deficiency. The condition develops due to destruction of pancreatic beta cells, mostly by immune-mediated mechanisms. In some patients there may be no evidence of autoimmune destruction of pancreatic beta cells; this is called idiopathic type 1 diabetes.
History and exam
Key diagnostic factors
Other diagnostic factors
- young age
- weight loss
- blurred vision
- nausea and vomiting
- abdominal pain
- clinical dehydration
- abdominal pain
- coma or altered mental status
- genetic predisposition
- geographical region
- infectious agents
- dietary factors
1st investigations to order
- random plasma glucose (children)
- fasting plasma glucose (children)
- 2-hour plasma glucose (children)
- HbA1c (children)
- clinical diagnosis (adults)
Investigations to consider
- plasma or urine ketones
- autoimmune markers
children and non-pregnant adults
- Monogenic diabetes: maturity onset diabetes of the young
- Neonatal diabetes
- Latent autoimmune diabetes in adults (LADA)
- Type 1 diabetes in adults: diagnosis and management
- Diabetes (type 1 and type 2) in children and young people: diagnosis and management
Diabetes type 1: what is it?
Diabetes type 1: what treatments work?More Patient leaflets
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