The principal two idiopathic forms of diabetes mellitus are
known as types 1 and 2. The term "type�1 diabetes" has universally
replaced several former terms, including childhood-onset diabetes,
juvenile diabetes, and insulin-dependent diabetes. Likewise, the
term "type�2 diabetes" has replaced several former terms, including
adult-onset diabetes, obesity-related diabetes, and
non-insulin-dependent diabetes.
Beyond these two types, there is no agreed-upon standard
nomenclature. Various sources have defined "type 3 diabetes" as,
among others, gestational diabetes, insulin-resistant type�1
diabetes (or "double diabetes"), type�2 diabetes which has
progressed to require injected insulin, and latent autoimmune
diabetes of adults.
There is also maturity onset diabetes of the young which is a
group of several single gene (monogenic) disorders with strong
family histories that present as type�2 diabetes before 30 years of
age.
