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What are the early symptoms of high blood glucose in diabetes mellitus?

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An anatomical illustration of the human pancreas shows its location near the stomach and intestines, a detailed cross-section highlighting ducts and the islet of Langerhans, and an inset of pancreatic tissue histology with labeled alpha, beta, and delta cells. — diabetes mellitus The islets of Langerhans are responsible for the endocrine function of the pancreas. Each islet contains beta, alpha, delta, and pancreatic polypeptide (PP) cells that are responsible for the secretion of pancreatic hormones. Beta cells secrete insulin, a well-characterized hormone that plays an important role in regulating glucose metabolism.

In the context of diabetes mellitus, symptoms of high blood glucose (hyperglycemia) typically manifest when blood glucose concentrations reach approximately 180 mg per 100 ml or higher.1

When blood glucose levels are elevated, the kidneys are unable to reabsorb all the filtered glucose, leading to its excretion in the urine. This process creates an osmotic effect that draws water from the body, resulting in the following primary symptoms:

Polyuria: The excretion of large volumes of urine.12
Polydipsia: Excessive thirst caused by the loss of body fluids.1

As the condition persists or worsens, other common symptoms include:

Fatigue and weakness: Resulting from the loss of glucose in the urine.13
Polyphagia: Increased appetite.1
Weight loss: Often associated with the body's inability to utilize glucose effectively.1
Increased susceptibility to infection: Particularly urinary tract infections and vaginal infections.13

It is important to note that mild hyperglycemia may not cause noticeable symptoms, and the disease is often discovered only after these typical signs become apparent. If you are experiencing these symptoms, please consult a medical professional, as untreated hyperglycemia can lead to serious complications.3415