ClassificationDiabetes can be classified into the following general categories1. Type 1 diabetes (due to autoimmune b cell destruction usually leading to absolute insuln deficiency
including latent autoimmune diabetes of adult hood
2. Type 2 diabetes (due to a progressive loss of b-cell insulin secretion frequently on the background of insulin resistance)
.Specific types of diabetes due to other cause,monogenic diabetes syndromes (such as neonatal di-
abetes and maturity-onset diabetes of the young), diseases of the exocrine pancreas (such as cystic fibrosis and pancreatitis), and drug- or chemical induced diabetes (such as with glucocorticoid use,in the treatment of HIV/AIDS, or after organtransplantation)4.Gestational diabetes mellitus (GDM; diabetes diagnosed in the second or third trimester of pregnancy that was not clearly
overt diabetes prior to gestation)
The classification of diabetes type is not always straight-forward at presentation, and misdiagnosis may occur. Therefore, constant diligence and sometimes reevalua-
tion is necessary. Children with type 1diabetes typically
present with polyuria and polydipsia, and approxi-mately half present with diabetic ketoacidosis (DKA).
Adults with type
1 diabetes can be diagnosed at any ageand may not present with classic symptoms. They mayhave temporary remission from the need for insulin.The diagnosis may become more obvious. over time and should be reevaluated if
there is concern
Screening and Diagnostic Tests for Prediabetes and Type 2 Diabetes
The diagnostic criteria for diabetes and prediabetes are shown in Table 2.2/2.5. Screening criteria for adults and children are listed in Table 2.3 and Table 2.4, respectively.
Screening for prediabetes and type 2 diabetes risk through an informal assessment of risk factors
Adapted from Tables 2.2 and 2.5 in the complete 2023 Standards of Care. *
For all three tests, risk is continuous, extending below the lower limit of the range and becoming disproportionately greater at the higher end of the range.
†In the absence of unequivocal hyperglycemia, diagnosis requires two abnormal test results from the same sample or in two separate samples.
‡Only diagnostic in a patient with classicsymptoms of hyperglycemia or hyperglycemic crisis.