Diabetes mellitus is a common endocrine disorder in companion animals, particularly in middle-aged and senior dogs and cats, caused by the body's inability to produce or use insulin.

It represents a growing challenge in veterinary medicine, due to the increase in the life expectancy of pets, the prevalence of obesity, and changes in the lifestyles of companion animals. It is estimated that one in every 300 dogs and cats will develop diabetes mellitus during their lifetime.

Its importance lies not only in its frequency, but also in the serious complications it can cause if not treated in time. This disease, considered chronic but manageable, requires early detection, continuous monitoring, and commitment from the owner and veterinary team. Therefore, owner education, preventive check-ups, and timely diagnosis are fundamental pillars for improving the quality and duration of life of diabetic patients.

Diabetes in companion animals is not only a clinical problem, but also an opportunity to strengthen the link between preventive medicine and animal welfare.

•  Most common type:  Type I diabetes (insulin-dependent).

•  Common causes:  Autoimmune destruction of pancreatic beta cells, chronic pancreatitis, genetic predisposition, obesity.

•  Common symptoms:  Polyuria (increased urination), polydipsia (increased water consumption), weight loss, polyphagia (Increased appetite) and lethargy.

•  Most common type:  Type II diabetes (insulin resistance).

•  Predisposing factors:  Obesity, inactivity, advanced age, use of glucocorticoids, concurrent diseases.

•  Common symptoms:  Polyuria (increased urination), polydipsia (increased water consumption), weight loss and polyphagia (increased appetite). In advanced cases, weakness in hind limbs (diabetic neuropathy).

•  Prevents serious complications: Such as diabetic ketoacidosis, which can be fatal, recurrent infections, cataracts (in dogs) and neuropathies (in cats).

•  Improves prognosis: Early treatment stabilises the patient and, in cats, can even achieve clinical remission in some cases.

•  Improves quality of life: Early glucose control helps keep the animal active, in good physical condition and with fewer clinical signs.

•  Reduces long-term cost: Detecting and treating diabetes before serious complications occur avoid costly hospitalisations.

It is crucial that veterinarians educate guardians about clinical signs and perform regular check-ups, especially in animals with risk factors such as obesity or advanced age.

The fructosamine concentration reflects the average blood glucose level in the 2-3 weeks prior to the measurement, by measuring glycated serum proteins, primarily albumin. Unlike glucose, fructosamine does not increase simply due to stress, which is usual in veterinary visits and during blood sample collection.

Why test it?
- Helps distinguish between transient hyperglycemia (e.g., due to stress) and persistent hyperglycemia.
- Ideal for long-term monitoring of glycemic control in treated animals.

Reference range:
- Dogs: 0.225 - 0.365 mmol/L
- Cats: 0.190 - 0.365 mmol/L

High fructosamine values, in combination with elevated glucose and other clinical symptoms, may indicate a diagnosis of diabetes mellitus. Low values, on the other hand, are related to hypoglycemia. In the case of animals subjected to insulin treatment, values outside the reference ranges indicate poor glycemic control and require a revision of the insulin dose.

BHB is the main ketone body in blood and the most sensitive marker for detecting ketosis and early diabetic ketoacidosis (DKA), even before it appears in urine.

Why test it?
- Detects early metabolic decompensation.
- Useful in patients showing lethargy, anorexia, vomiting, or unexplained weight loss.

Reference range:
- < 0.4 mmol/L (dogs and cats)
- Suspicion of ketosis: > 0.8 mmol/L
- DKA likely: > 2.0 mmol/L

NEFAs are released when the body mobilizes fat as an energy source, typically due to insulin deficiency or prolonged fasting.

Why test it?
- Elevated levels are an early sign of negative energy balance and potential ketosis.
- Particularly useful in diabetic cats with weight loss but maintained appetite.

Reference range:
- Dogs: < 0.7 mmol/L
- Cats: < 1.0 mmol/L