Lauren Liba

1
Diabetes Insipidus in Canines

• Lauren Liba
• Eric Malarney

2
(No Transcript)
3
What is Diabetes Insipidus???

• A disorder of water imbalance
• This disorder is a completely different disease
  from diabetes mellitus, which is a disorder of
  glucose metabolism involving the hormone insulin

4
What is Diabetes Insipidus???

• The animal is unable to concentrate urine
• The urine volume is high and very dilute
• The urine is odorless (insipid), not sweet
  smelling as in diabetes mellitus
• The disease is rare in canines and felines
• The condition is usually
  permanent, but with proper
  treatment, the
  prognosis is
  good

5
Types of Diabetes Insipidus

• Central Diabetes Insipidus
• Caused by the destruction of cells within the
  supraoptic and paraventricular nuclei of the
  hypothalamus which result in a deficiency in of
  antidiuretic hormone (ADH)
• Can also be due to the loss of
  the ducts (axons) that transport
  (ADH) to the posterior
  pituitary

6
Hypothalamus
x
x
Supraoptic Nucleus
No production of antidiurectic hormone (ADH)
Paraventricular Nucleus
Ant. Pit.
Posterior Pituitary
7
Hypothalamus
Supraoptic Nucleus
x
Loss of ducts to the posterior pituitary - No
antidiuretic hormone (ADH)
Paraventricular Nucleus
Ant. Pit.
Posterior Pituitary
8
Other Causes of Central Diabetes Insipidus

• Congenital Defect
• Trauma
• Tumor of the pituitary gland
• Unknown cause

9
Types of Diabetes Insipidus

• Nephrogenic Diabetes Insipidus
• Caused when the kidneys do not respond to
  antidiurtetic hormone (ADH)
• Can be caused by congenital defects, drugs, or
  other metabolic disorders

10
Posterior Pituitary
No urine concentration
(ADH)
X
11
Differential Diagnoses

• Hyperadrenocorticism (Cushings Disease)
• Diabetes Mellitus
• Hyperthyroidism (in felines)
• Renal Failure
• Liver Disease
• Pyometra
• Hypercalcemia of malignancy
• Hyperparathyroidism

12
Signs of Diabetes Insipidus

• Polyuria
• Polydipsia
• Dehydration - which can lead to stupor, coma, and
  even death if untreated
• Housebroken canines urinating indoors

13
Treatment of Central Diabetes Insipidus

• Treated with desmopressin (DDAVP) via
  intranasal drops, eyedrops, or subcutaneous
  injections

14
Treatment of Nephrogenic Diabetes Insipidus

• Treat with a thiazide drug, chlorothiazide, or an
  oral drug, chloropropamide
• NSAIDs can also be used
• Regardless of treatment, water must ALWAYS be
  available

15
Diagnostic Tests

• Images of pituitary gland should be
  taken if possible
• Water deprivation test
• An ADH trial with the drug desmopression (trade
  name DDAVP)

16
Additional Facts

• Very rare disease, particularly central diabetes
  insipidus (a study in JAVMA found only 43 cases
  of CDI from 1986 to 1995 at UC-Davis and Purdue)
• No breed predilections
• Age does not appear to be a factor

JAVMA, Vol 209, No. 11, December 1, 1996
17
(No Transcript)
18
(No Transcript)
19
Central Diabetes Insipidus

• Case Study
• Eddie
• Pointer mix
• NM
• 4 years old

20
Chief Complaint

• Inappropriate urination, polyuria/polydipsia one
  week duration
• Physical exam otherwise normal
• Consider behavioral issues

21
Polyuria and polydipsia
22
Polyuria and polydipsia
23
Polyuria and polydipsia
questionable
present
24
Polyuria and polydipsia
Polyuria and polydipsia
questionable
present
Monitor water intake and SG
25
Polyuria and polydipsia
questionable
present
Monitor water intake and SG
normal
Consider incontinence
26
Polyuria and polydipsia
questionable
present
abnormal
Differential diagnosis
Monitor water intake and SG
normal
Consider incontinence
27
Polyuria and polydipsia
questionable
present
Differential diagnosis
abnormal
Monitor water intake and SG
CBC Serum chem UA
normal
Consider incontinence
28
Polyuria and polydipsia
questionable
present
abnormal
Differential diagnosis
Monitor water intake and SG
CBC Serum chem UA
normal
Consider incontinence
Consider hyperadrenocorticism
29
Polyuria and polydipsia
questionable
present
abnormal
Differential diagnosis
Monitor water intake and SG
CBC Serum chem UA
normal
Consider incontinence
Consider hyperadrenocorticism
normal
Water Deprivation Test
30
Lab Test Results

• Consistent with Diabetes Insipidus
• Normal serum chem and CBC or values consistent
  with mild dehydration
• Increased PCV, TP and Na
• Urinalysis normal except specific gravity
• Below 1.025
• Normal radiography

31
Abrupt Water Deprivation Test

• Empty urinary bladder and measure urine specific
  gravity
• Weigh animal
• Withhold food and water
• Every 2-4 hours, reweigh animal, empty urinary
  bladder and measure specific gravity

32
Gradual Water Deprivation Test

• Quantify daily unrestricted water consumption
• Measure urine specific gravity and weigh animal
• Reduce water intake by 5 daily
• Weigh animal and measure specific gravity daily

33
Deprivation Test Outcomes

• Stop the test when
• The animal loses more than 5 of its body weight
• The animal is clinically dehydrated or ill
• The urine specific gravity exceeds 1.025

34
Lab tests
Dehydration, azotemia, hypercalcemia?
35
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
36
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
Water deprivation
37
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
no
Water deprivation
38
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
no
Water Deprivation Test
Water deprivation
39
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
no
Water Deprivation Test
Water deprivation
Concentrated urine?
40
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
no
Water Deprivation Test
Water deprivation
Concentrated urine?
yes
Find underlying cause- nervous, behavioral
41
Lab tests
Dehydration, azotemia, hypercalcemia?
yes
no
Water Deprivation Test
Water deprivation
Concentrated urine?
yes
no
Find underlying cause- nervous, behavioral
Give ADH
42
ADH Response Test

• Immediately following water deprivation test
  administer aqueous vasopressin
• Withhold all food and water
• Empty bladder and measure urine specific at 30,
  60, 90 and 120 minutes

43
Therapeutic ADH Trial

• Administer intranasal preparation of DDAVP in
  conjunctival sac (1 to 4 drops q12h) for 3-5 days
• Should see a dramatic reduction in water intake
  if central diabetes insipidus is present

44
Urine is not concentrated after water deprivation
Give ADH (DDAVP)
45
Urine is not concentrated after water deprivation
Give ADH (DDAVP)
Concentrated
Not concentrated
46
Urine is not concentrated after water deprivation
Give ADH (DDAVP)
Concentrated
Not concentrated
Nephrogenic diabetes insipidus
47
Urine is not concentrated after water deprivation
Give ADH (DDAVP)
Concentrated
Not concentrated
Nephrogenic Diabetes Insipidus
Pursue further renal testing
48
Urine is not concentrated after water deprivation
Give ADH (DDAVP)
Concentrated
Not concentrated
EDDIE
Nephrogenic Diabetes Insipidus
Central Diabetes Insipidus
Pursue further renal testing
49
Urine is not concentrated after water deprivation
Give ADH (DDAVP)
Concentrated
Not concentrated
EDDIE
Nephrogenic diabetes insipidus
Central Diabetes Insipidus
Pursue further renal testing
Find underlying cause
50
Treatments

• Desmopressin acetate (DDAVP)
• Aqueous solution or oral tablets
• Best solution, but expensive
• Hydrochlorothiazide
• Diruretic
• Not as effective as DDAVP
• Chlopropamide
• Hypoglycemic agent
• Only if ADH deficiency is partial

51
References

• Birchard, Sherding. Saunders Manual of Small
  Animal Practice. Second edition, pp 300-303,
  2000.
• Cunningham. Textbook of Veterinary Physiology.
  Second edition, pp 396-398, 2000.
• Ettinger, Feldmen. Textbook of Veterinary
  Internal Medicine. Fifth edition, volume 2, ch.
  148, pp 1374-1379.
• Tilley, Smith. The Five Minute Veterinary
  Consult, second edition, pp 616-617, 2000.
• petdiabetes.org/diabetes_insipidus.htm
• ndif.org/facts.html
• www.vetinfo.com/dencyclopedia/dedibetinsp.html
• familydoctor.org/handouts/048.html
• www.histo.org/association/library/diabetes.xml
• JAVMA, vol 209, No. 11, December 1, 1996, pp.
  1184-1888

52
Questions?