Type 1 Diabetes usually starts abruptly and mostly affects young children. So the diagnosis happens only when the symptoms are very evident and most of the patients are hospitalized with a condition called Diabetic Ketoacidosis before they are diagnosed.
Once the doctor suspect Type 1 diabetes, diagnosis is confirmed with check on Blood glucose levels.
Multiple tests are conducted to confirm blood glucose levels such as Fasting (Usually done in the morning after fasting overnight). Random (Current Glucose level taken at random time, usually done as a first test), Glycated hemoglobin test (Known as HbA1C test this shows the average blood sugar levels for the past three months or so. This is considered a more comprehensive test to show the actual level of blood glucose.
Doctors may prescribe other tests such as C-Peptide also for confirming T1D diagnosis– This test measures the C-peptide levels in a person’s blood. Peptide levels normally shows the insulin levels in body. Low levels of C-peptide may mean low level of Insulin in body and is a pointer towards Type 1 Diabetes.
Ketone testing is also used sometimes. The ketone test is done using a urine sample or blood sample. Ketone testing may be done to determine if someone with type 1 diabetes has had ketoacidosis. Testing is usually done:
- When the blood sugar is higher than 240 mg/dL (13.3 mmol/L)
- During an illness such as pneumonia, heart attack, or stroke
- When nausea and vomiting occur
- During pregnancy