The Endocrine Pancreas

Question 1

What disorders can you get in the endocrine pancreas?

Answer 1

Diabetes mellitus

Insulinoma

Question 2

How would you best define diabetes mellitus?

Answer 2

Clinically significant glucose intolerance caused by an absolute or relative lack of insulin.

Question 3

What are the clinical signs of diabetes mellitus?

Answer 3

PU/PD
Weight loss and polyphagia
Muscle wasting
Hepatomegaly 
Cataracts

Question 4

What are the clinical signs of ketoacidosis?

Answer 4

Dehydration
Depression
Inappetence
V/D

Question 5

What clinical biochemical abnormalities might you seen in a diabetic?

Answer 5

Fasting hyperglycaemia (>14mmol/L)
Elevated ALP and ALT as a result of hepatic lipidosis
Hypercholesterolaemia, hypertiglyceridaemia
Azotemia if decreased renal perfusion

Question 6

How could you differentiate between stress hyperglycaemia and diabetes?

Answer 6

Fructosamine level could be measured

Question 7

How would you treat uncomplicated diabetes mellitus?

Answer 7

Treat any underlying causes for insulin resistance e.g. weight loss
Insulin therapy
Oral hypoglycaemic

Question 8

Oral hypoglycaemia agents are better in which small animal species?

Answer 8

Cats, they are almost always ineffective in managing diabetic dogs.

Question 9

What might be a complication to oral hypoglycaemia agent use?

Answer 9

They are thought to accelerate islet cell exhaustion

Question 10

Give an example of an oral hypoglycaemic agent

Answer 10

Glipizide

Question 11

What is the dose rate for an oral hypoglycaemia agent in a cat and dog?

Answer 11

Cat: 5mg BID-TID
Dog: 0.2-0.5mg/kg BID

Question 12

What are the only current licensed insulin’s in the UK?

Answer 12

Caninsulin (PROCINE ORIGIN)

ProZinc (HUMAN RECOMBINANT)

Question 13

What is the time of peak effect for Caninsulin and how long will it last for?

Answer 13

Peak effect 1-4HRS after administration

Lasts for approx. 12-14 hours

Question 14

Describe the general practical guidelines to insulin therapy in dogs

Answer 14

1. Initially start at 0.25-0.5 IU/KG subcutaneous BID
2. Feed 30-90mins after insulin administration
3. Check blood glucose q2-3 7 days after starting therapy
4. Increase dose according to blood glucose and clinical picture

Question 15

Describe the general practical guidelines for insulin therapy in cats…

Answer 15

1. Start on insulin dose of 1 or 2 units of PZI BID nd then follow the steps as for a dog.

Question 16

Why can food and insulin be given at the same time in a cat but not in the dog?

Answer 16

Cats do not have a pronounced post-prandial hyperglycaemia where as dogs do.

Question 17

What is the pathophysiology of diabetic ketoacidosis?

Answer 17

When glucose deficiency occurs, the liver will start oxidation of non-esterified fatty acids as an alternate energy source. Oxidation of free fatty acids (FFA) gives ride to ketone (aceto-acetate, beta-hydroxybutyrate and acetone). Insulin is usually an inhibitor of lipolysis and FFA oxidation, therefore absolute or relative absence of insulin will cause lipolysis and FFA oxidation.

Question 18

How would you diagnose DKA?

Answer 18

Previous diagnosis of diabetes mellitus

Ketonuria/kentonaemia

Question 19

How would you initially approach a DKA patient?

Answer 19

1) What is the underlying reason for the DKA episode?

2) Is the patient ketotoic or ketoacidotic?

Question 20

What treatment would you give for a DKA patient?

Answer 20

IVFT - 0.9% saline at 60-100ml/kg/day. Make sure K supplementation is included as once insulin treatment starts it will lower K to intracelluar. Phosphate supplementation may also be needed since haemolytic anaemia may ensure with falling levels.
Insulin therapy - Make sure you monitor, only induce gradual changes and reduce the amount administered when dealing with a hypokalaemia patient. Initially IM dose of 0.2 IU.KG followed by 0.1 UI/KG q1 has been successfully used until BG is 10-15mmol/l then 0.1-0.4IU/KG every 6-8HRs. When BG is down to that level, dextrose or glucose should be started IV at 1-2x maintenance.
Ancillary therapy - concurrent disease may need to be addressed e.g. pancreatitis, UTI and other infections.
Bicarbonate therapy - least necessary and should actually be avoided where possible

Question 21

What are the clinical signs of insulinoma?

Answer 21

Dominated by the effects of hypoglycaemia on the central nervous system:
Mentation, weakness, ataxia, behaviour, coma and death. Clinical signs related to increased catecholamine release include muscle tremors, hunger and anxiety.

Question 22

How would you diagnose insulinoma?

Answer 22

When suspect, starve patient and take BG every 2-4 hours. Abdominal ultrasound may reveal a focal structure in the pancreas.

Question 23

What is the treatment for insulinoma?

Answer 23

Ideally surgery. If not possible medical therapy may include:
Prednisolone (inducing insulin resistance)
Diazoxide (Inhibiting insulin secretion)
Frequent small meals of low carbs and high protein.