Certain diseases may contribute to
the development of diabetes. AcromegalyAcromegaly is a rare
endocrine disease caused by growth hormone excess. It is characterized
by chronic overgrowth of connective tissue, bone and viscera.
Among other clinical signs, insulin resistant diabetes and enlargement
of soft tissue organs and proliferation of gum tissue is seen. Dogs generally develop
acromegaly due to progesterone secretion and growth hormone production
by the mammary glands. Acromegaly may rarely be caused by pituitary
or hypothalamic neoplasia.
Spaying of bitches is usually curative, although the concurrent
diabetes may be permanent, depending on the remaining ability of
the pancreas to secrete insulin.
Exocrine pancreatic insufficiency (EPI)
Exocrine pancreatic insufficiency
is a congenital or acquired condition that can affect both dogs
and cats, although it is more common in dogs. Young adult dogs,
especially German Shepherds, are usually affected. In dogs EPI is usually
due to pancreatic acinar atrophy (PAA). It may be seen together
with diabetes mellitus if there is damage to both the exocrine and
endocrine pancreas.
Pathophysiology
- Digestive enzymes are not secreted normally by the pancreas
- Food is not sufficiently digested and processed
- Diarrhoea and weight loss in spite of a normal or increased
appetite
Diagnosis and
treatment
EPI is diagnosed on the basis of blood tests and is treated with
pancreatic enzyme replacements, e.g. Tryplase
(Intervet). Enzyme replacements usually result in improvement
of the clinical signs, and dietary management. However, if due to
chronic pancreatitis and accompanied by diabetes mellitus, it can
be more difficult to treat successfully.
Hyperadrenocorticism (Cushing’s
disease)
Hyperadrenocorticism
is a relatively common endocrine disease of dogs but is rare in
cats. Aetiology - Excessive endogenous cortisol production
- pituitary tumour (85% of cases) producing excessive adrenocorticotrophic
hormone (ACTH) or
- an adrenal (15% of cases) tumour) producing excessive cortisol
- Iatrogenic administration of exogenous glucocorticoids (iatrogenic
hyperadrenocorticism).
Clinical signs
Hyperadrenocorticism is a slowly progressive disease with signs
that vary in severity depending on the duration and degree of cortisol
excess. Clinical signs are similar
to diabetes mellitus: - polyuria
- polydipsia
- polyphagia
In addition dogs frequently
have a pot-bellied appearance and alopecia or other skin and/or
coat changes. Diabetes mellitus may develop secondary to hyperadrenocorticism,
due to insulin resistance caused by cortisol excess. Treatment
Hyperadrenocorticism can be treated medically or surgically. Concurrent
diabetes mellitus requires insulin treatment.
Pancreatitis Pancreatitis is inflammation
of the pancreas. Digestive enzymes leak into and damage the surrounding
pancreatic tissues. Aetiology
In most cases the cause of pancreatitis is idiopathic. Other predisposing
factors may be: - high fat, low protein diet
- other diseases (Cushing's disease, diabetes mellitus)
Risk factors for pancreatitis
include: - breed - Miniature Schnauzer, Miniature poodle and Cocker spaniel
are at higher risk
- obesity
- diabetes mellitus
- Cushing's disease
- chronic renal failure
Acute pancreatitis may
produce temporary diabetes mellitus and if there is extensive pancreatic
necrosis this may become permanent. A similar situation can arise
if there is pancreatic neoplasia. | 
About
diabetes
