Diabetes Mellitus - Feline

Question 1

What are the major risk factors for diabetes mellitus in cats?

Answer 1

Male

Obesity

Burmese (8x more likely)

Age (biphasic)

Corticosteroids, megestrol

Question 2

Secretion of what hormone in cats is toxic to pancreatic beta cells and decreases their response to high blood glucose levels?

Answer 2

Amylin

*Islet amyloidosis is an important part if diabetes in cats!

Question 3

T/F: Every diabetic cat will benefit from insulin.

Answer 3

TRUE

*By the time we diagnose diabetes in cats, they are already hyperglycemic, meaning the beta cells are damaged enough by amylin that they’re not producing enough insulin.

Question 4

T/F: The goal of treatment in diabetic cats is similar to that of diabetic dogs.

Answer 4

FALSE

Cats can have a transient requirement for exogenous insulin. In 50-90% of cases, by treating the primary problem (obesity, drugs, concurrent diseases), cats can be taken off insulin.

Question 5

A 13 year old 4kg MN Burmese cat named Spronkers presents for urinating outside the box and weight loss. On exam you notice that Spronkers has a plantigrade stance. He is mildly dehydrated and is painful on palpatio of the cranial abdomen. You do a urinalysis and find 3+ glucose and USG of 1.035. What is the cause for glucosuria in this patient?

Answer 5

Blood glucose level over the renal threshold (300mg/dL in cats)

Question 6

Is glucosuria diagnostic for diabetes mellitus in Spronkers?

Answer 6

No. BG above the renal threshold can be achieved with a stress response. Glucosuria must be interpreted in light of other results and clinical signs.

Question 7

Bloods on Spronkers show a lymphopenia, and hypokalemia, and increased ALT, ALP, Crea, Glu, and fructosamine. What about this chemistry indicates that the elevated Glu is not just a result of stress?

Answer 7

Increased fructosamine

Question 8

While you are out of the country on business, your colleague takes over Spronkers’ case and starts him on 2U lente insulin SID. Is this an appropriate dose for a 4kg cat?

Answer 8

Nope.

(025U/kg = 1U for a 4kg cat)

ALSO, lente insulin has a 12 hour duration and shouldn’t be given SID.

Question 9

Spronkers is showing no improvement on his current insulin dose of 2U SID. Your colleague increases the dose by one unit each week until eventually Spronkers is getting 6U SID. Is this an appropriate weekly increase for cats?

Answer 9

Nope.

Insulin should be increased by 0.5U per week in cats.

Question 10

When you arrive back to the office you find Spronkers has lost even more weight and is markedly plantigrade, with a poor coat quality. What complications should you consider in uncontrolled diabetics?

Answer 10

Concurrent disease

Insufficient dosage

Poor injection technique or storage

Question 11

You treat Spronkers for a UTI and pancreatitis. He seems to be feeling better but his glucose is still condsistently high. You do a curve each day he’s in the hospital and his glucose level stays around 400mg/dL consistently. However, you find that on day 3, after his insulin treatment, his BG drops very quickly. What is the reason for this phenomenon.

Answer 11

Somogyi Effect

*Insulin dose is too high

Question 12

You change Spronkers’ insulin dose to 1U BID and recommend a diabetes friendly diet. What kind of diet should the owner buy?

Answer 12

High protein diet

*A high protein diet increases the effect of hexokinase, which reduces glucose levels in the blood

Question 13

In peakless insulins like Deltemir, Glargine, and Prozinc, why can’t you increase the dose for at least 5-7 days after starting treatment?

Answer 13

Concentration builds up over 5 days until it reaches steady state.