Type 1 Diabetes: Symptoms And Diagnosis


The diagnosis of Type 1 diabetes meets specific biological standards. Modern techniques have thus helped to refine diagnosis and differentiate Type 1 diabetes (still often referred to as “Juvenile diabetes”) from other Types of diabetes.

Cardinal Signs Of Type 1 Diabetes

The first symptoms of Type 1 diabetes appear once the pancreas stops producing insulin. The onset of the disease is revealed by distinct symptoms – or cardinal signs – caused by hyperglycemia. These symptoms can appear suddenly and include:

  • frequent urination (polyuria)
  • bedwetting in children who didn’t wet the bed anymore
  • extreme thirst (polydipsia)
  • excessive hunger (polyphagia)
  • unintended weight loss
  • blurred vision
  • fatigue and weakness

Sometimes, the discovery of Type 1 diabetes is brutal and requires a visit to the ER, especially in the case of diabetic ketoacidosis or DKA. Insulin deficiency causes the breakdown of fatty tissue, resulting in the release of acidic compounds, called ketones. Ketoacidosis comes with Kussmaul breathing (ample breathing in four stages), nausea (or vomiting) as well as abdominal pain, which can sometimes be mistaken for appendicitis. There is often a fruity odor in the breath.

These symptoms can sometimes lead to coma. DKA occurs in cases of total insulin deficiency, often after several weeks with undetected and untreated diabetes.

Biological Diagnosis Of Type 1 Diabetes

Type 1 diabetes often appears with acute symptoms, leading to a visit to the doctor’s or the emergency room. However, a blood test is still required to confirm diagnosis. In practice, blood sugar levels above 200 mg/dL, when combined with the typical symptoms of Type 1 diabetes, are enough to  make a diagnosis.

Other possible tests:

However, these tests are often performed when no other symptoms are present and more frequently to diagnose Type 2 diabetes.

Confirming The Autoimmune Origin

Once the diagnosis is confirmed, we can investigate the autoimmune nature of Type 1 diabetes; a blood test reveals the presence of antibodies that are specific to Type 1 diabetes. Some elements may also contribute to the diagnosis of Type 1 diabetes such as the absence of a family history. The presence of other autoimmune diseases supports the diagnosis of Type 1 diabetes.

Read more: Autoimmune Diseases Associated With Type 1 Diabetes

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