Download Classification of diabetes

Classification of diabetes
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Type 1 Diabetes Mellitus. These patients usually present as children or young
adults, but it is important to be aware that they may present at any age. Their
hallmark is insulin deficiency due to autoimmune pancreatic cell destruction,
resulting in weight loss and the presence of ketones in the urine. Such patients are
prone to ketoacidosis, and once diagnosed should be treated with insulin as a
matter of urgency, although emergency hospital admission is often unnecessary.

Type 2 Diabetes Mellitus. Although most present in middle and old age, an
increasing number present at younger ages. Many are obese. Peripheral insulin
resistance combined with relative insulin deficiency accounts for the
pathogenesis. Ketonuria is absent in the non-fasting state. Such patients are not
normally prone to ketoacidosis.
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Other Types:
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Secondary Diabetes Mellitus: can be secondary to other conditions which
cause pancreatic destruction (haemochromatosis, cystic fibrosis, pancreatitis)
or associated with other syndromes which are characterised by insulin
resistance (acromegaly, polycystic ovarian syndrome, Cushing’s syndrome)
and drug therapy, particularly glucocorticoids. See Appendix 3 - Secondary
Diabetes

Recognised Genetic Syndromes: including MODY (maturity onset diabetes of
youth), which is characterised by early onset diabetes and no requirement for
insulin (non-ketotic). Patients are often of normal weight. The condition is
inherited in an autosomal dominant fashion and there is almost always a
family history.
Gestational Diabetes Mellitus is defined as glucose intolerance of variable
severity with first onset or recognition during pregnancy. In most women the
abnormality is reversible post partum, but up to 50% develop Type 2 diabetes
later in life. A small proportion have coincidental Type 1 diabetes presenting in
pregnancy.