Diagnosis and management overview
Diagnosing feline diabetes
Diagnosing feline diabetes can be challenging. Cats presenting persistent classic clinical signs of diabetes, such as polydipsia (PD), polyuria (PU), and weight loss despite good appetite should be further monitored for corroborative laboratory test results showing hyperglycemia and glycosuria. Also, conduct blood serum and urinalysis testing to rule out infections and other underlying medical conditions. Plantigrade stance presents as a characteristic clinical sign of advanced feline diabetes.
Confirm a preliminary diagnosis of diabetes mellitus based on clinical signs with blood and urine tests. Glycosuria combined with hyperglycemia (>300 mg/dL) indicates diabetes mellitus. Although it is common for non-diabetic cats to develop transient hyperglycemia in times of stress, such as during blood sample collection, the urine glucose should be negative in a non-diabetic cat.
Because stress-induced hyperglycemia can result in blood glucose concentrations of 300 mg/dL to 400 mg/dL, it can confound the interpretation of blood glucose results. Persistent hyperglycemia and glycosuria should therefore be present to definitively establish diabetes diagnosis. It’s useful to measure serum fructosamine concentrations because they remain normal in stress-induced hyperglycemia and elevated in sustained hyperglycemia.
Evaluating glucose accumulation in urine is a useful diagnostic tool in making a definitive diagnosis of diabetes in cats. Since it takes several hours of stress for detectable glucose to accumulate in the urine, glycosuria will not be present in cats with stress-induced hyperglycemia. In addition to the absence of glycosuria, none of the typical clinical signs of diabetes are present in cats with stress-induced hyperglycemia.
When a diagnosis of diabetes has been confirmed, begin management with Vetsulin® (porcine insulin zinc suspension).
Feline diabetes management overview
The goals in managing diabetes mellitus are to minimize the clinical signs of diabetes, the risk of hypoglycemia, and the development of long-term complications. Accomplishing these 3 goals requires that pet owners understand all aspects of diabetes management. It pays to invest sufficient time to carefully explain all aspects of diabetes therapy to your clients.
Managing diabetes can be an exercise in frustration until stabilization occurs; however, this website offers help to veterinary professionals as they evaluate the disease and its management. It also provides tools and resources (see additional support).
Management of diabetes mellitus in cats includes insulin and diet. For intact females, spaying is required because of the hormonal changes during the estrous cycle. In particular, the elevated progesterone level is antagonistic to the action of insulin. Oral hypoglycemic agents have a limited use in type 2 feline diabetics.
Insulin forms one of the cornerstones of the management of diabetes mellitus; therefore, it’s important to understand the length of action of insulin and how to evaluate therapy.
How to evaluate management
Tools that are available to assist you include:
- Glucose curves
- Punctual blood samples
- Evaluation of glycosuria and monitoring
- Clinical signs
- Glycosylated hemoglobin and fructosamine
Monitoring blood glucose is a good way to evaluate regulation of diabetic cats. It’s accurate, quick, and requires only a drop of blood. However, in certain conditions (see below), it’s not reliable because blood glucose concentration is influenced by many factors and may not show an accurate result of insulin management.
Various factors such as economics, logistics, and clinical situations can also force veterinarians to limit diagnostic procedures. When it’s not possible to perform a complete glucose curve, punctual blood samples combined with assessment of clinical signs, general observations, and evaluating glycosuria can provide an overview of the diabetic animal. Veterinarians can also rely on evaluation of glycosylated hemoglobin (GHb) and fructosamine in laboratory testing.
Non-insulin factors affecting management
Food intake, cat and owner cooperation, use of a drug (eg, prednisolone, progestogens, megestrol acetate), concurrent disease conditions (eg,hyperadrenocorticism, acromegaly), or stress can affect blood glucose levels. In these cases, blood glucose measurement will need to be interpreted in combination with other methods of evaluation.