Download Causes of polyuria, polydipsia, and hyposthenuria

Table 2.1.1 Causes of polyuria, polydipsia, and hyposthenuria
Causes of polyuria and polydipsia
Definition
Causes of isosthenuria
USG 1.008–1.030
Chronic renal failure
Diabetes mellitus
Hyperadrenocorticism
Hypercalcemia
Hypoadrenocorticism
Hypokalemia
Liver disease
Pyelonephritis
Pyometra
Causes of hyposthenuria
USG < 1.008
Diabetes insipidus
Hyperadrenocorticism
Hypercalcemia
Liver disease
Pyometra
USG, urine specific gravity.
Table 2.2.1 Clinical manifestations of canine hypothyroidism
Metabolic
Cardiovascular
Lethargy
Bradycardia
Mental dullness
Cardiac arrhythmias
Unexplained weight gain
Cold intolerance
Ocular
Corneal lipid deposits
Dermatologic
Keratoconjunctivitis sicca
Alopecia
Corneal ulceration
Seborrhea sicca, oleosa,
or dermatitis
Uveitis
Dry, brittle hair coat
Gastrointestinal
Changes in hair coat color
Diarrhea
Pyoderma
Constipation
Hyperpigmentation
Hematologic
Otitis externa
Anemia
Myxedema
Hyperlipidemia
Coagulopathy
Neuromuscular
Weakness
Reproductive
Ataxia
Female cycle abnormalities
Vestibular signs
Testicular atrophy
Facial nerve paralysis
Hypo/azoospermia
Seizures
Source: Feldman EC, Nelson RW. Hypothyroidism/the thyroid gland. In:
Canine and Feline Endocrinology and Reproduction, 3rd edition. St. Louis,
MO: Saunders Elsevier; 2004, 86+, print.
Table 2.2.2 Factors causing low T4 values in euthyroid animals
Factor
Example
Concurrent drug therapy
Prednisone, phenobarbital
Nonthyroidal illness
Hyperadrenocorticism
Naturally occurring different
reference ranges for specific
breeds
Greyhounds, whippets,
basenjis, sled dogs
Hourly fluctuations
Circadian cycle changes
Fasting over 48 h
Anorexia
Age
An older dog is more likely to
have lower TT4 values than a
younger dog
Ambient temperature
Car ride on a hot summer
day
Stress
Visit to the veterinary hospital
Sources: Wilford C, DVM (Veterinary News columnist for the AKC Gazette).
The enigmatic nature of hypothyroidism makes it difficult to distinguish from
other diseases. AKC Gazette November, 1995; pp. 67–71; Neiger R, Prof. Dr.
med. vet., PhD, DACVIM, DECVIM–CA. Canine hypothyroidism. In: 50°
Congresso Nazionale Multisala SCIVAC, Rimini, Italy. Giessen, Germany: Small
Animal Clinic, Justus-Liebig University; 2005.
Table 2.2.3 Common signs associated with feline hyperthyroidism
Weight loss
Polyphagia
Tachycardia
Heart murmurs
Palpable thyroid
Increased ALT/SAP
Polydipsia
Polyuria
Vomiting
Diarrhea
Unkempt appearance of skin and hair coat
Behavioral changes (i.e., increased vocalization, restlessness,
irritability)
Table 2.4.1 Sensitivity and specificity of endocrine screening tests in
dogs for the diagnosis of hyperadrenocorticism
Test
Sensitivity (%)
Specificity (%)
Basal cortisol
100
78.2
UC : CR
100
20
ACTH stimulation
60–85
85–90
LDDST
90–95
40–50
Source: Modified from Nelson RW, Feldman EC. Chapter 6: canine
hyperadrenocorticism. In: Endocrinology and Reproduction. Philadelphia, PA:
Elsevier Science 2004.
Table 2.5.1 Causes of insulin resistance in cats
Drug administration (progestagens/corticosteroids)
Infection (urinary tract/oral cavity/sepsis/bronchopneumonia)
Hyperthyroidism
Acromegaly
Pancreatic disease (pancreatitis, tumor)
Renal disease
Hepatic disease
Cardiac insufficiency
Hyperlipidemia
Neoplasia
Severe obesity
Exocrine pancreatic insufficiency
Hyperadrenocorticism
Pheochromocytoma
Source: Modified from Scott-Montcrieff JC. Insulin resistance in cats. Vet
Clinics of North America, Small Animal Practice 2010;40(2):241–257.
Table 2.5.2 Parameters for changing insulin dosage and frequency based on blood glucose measurements when using lente
or NPH insulin in cats
Blood glucose variable
Recommendations
Initial therapy
If blood glucose ≥360 mg/dL (>20 mmol/L)
Use of an initial dose of 0.5 U/kg of lean body weight BID
If blood glucose ≤360 mg/dL (<20 mmol/L)
Use of an initial dose of 0.25 U/kg of lean body weight BID
Nadir response
If nadir blood glucose concentration is <54 mg/dL
(<3 mmol/L)
Dose should be reduced by 50%
If nadir blood glucose is 54–90 mg/mL (3–5 mmol/L)
Dose should be reduced by 1 U if poor control of clinical signs of DM,
otherwise no change in dose
=If nadir blood glucose concentration is 91–180 mg/dL
(6–9 mmol/L)
Dose should remain the same
If nadir blood glucose concentration is >180 mg/dL
(>10 mmol/L)
Dose should be increased by 1 U
If nadir blood glucose concentration occurs at 8 h or later
Once-daily administration may be used, although BID administration
at a reduced dose is preferred
Baseline response
If blood glucose returns to baseline within 8 h
Change to longer-acting insulin (e.g., glargine, detemir, or PZI)
Or if nadir blood glucose concentration occurs within 3 h of
insulin administration
Source: Modified from Rand J, Marshall R. Management of feline diabetes mellitus: part I. Which insulin do I choose and how do I adjust the dose? ACVIM
2009 Proceedings, Quebec, Canada, June 3–6.
Table 2.5.3 Parameters for changing insulin dosage and frequency based on blood glucose measurements when using glargine insulin in cats
Blood glucose variable
Recommendations
Initial therapy
If blood glucose ≥360 mg/dL (>20 mmol/L)
Use of an initial dose of 0.5 U/kg of ideal body weight BID
If blood glucose ≤360 mg/dL (<20 mmol/L)
Use of an initial dose of 0.25 U/kg of ideal body weight BID
Note: Do not increase the dose in the first week unless minimum response to insulin occurs, but decrease if necessary. Monitor
response to therapy for first 3 days. If no monitoring occurs during the first week, begin with 1 U/cat BID
Preinsulin blood glucose level and nadir response
Preinsulin level
Nadir response
Recommendations
If preinsulin blood glucose concentration is
>216 mg/dL (>12 mmol/L) provided nadir is not
in hypoglycemic range
Or if nadir blood glucose
concentration is >180 mg/dL
(>10 mmol/L)
Increase by 0.25–1.0 U
If preinsulin blood glucose concentration is
180–216 mg/dL (10–12 mmol/L)
Or if nadir blood glucose
concentration is 90–160 mg/dL
(5–9 mmol/L)
Same dose
If preinsulin blood glucose concentration is
198–252 mg/dL (11–14 mmol/L)
Or if nadir glucose is 54–72 mg/dL
(3–4 mmol/L)
Use nadir glucose, water consumption,
urine glucose, and next preinsulin glucose
concentration to determine if insulin dose
should be decreased or maintained
If preinsulin blood glucose concentration is
<180 mg/dL (<10 mmol/L)
Or if nadir blood glucose is
<54 mg/dL (<3 mmol/L)
Dose should be reduced by 0.5–1.0 U or
if total dose is 0.5–1.0 U SID, stop insulin
and check for diabetic remission
Note: If clinical signs of hypoglycemia are observed
Reduce by 50%
Source: Modified from Rand J, Marshall R. Management of feline diabetes mellitus: part I. Which insulin do I choose and how do I adjust the dose? ACVIM
2009 Proceedings Quebec Canada June 3-6.
Table 2.5.4 Hormonal response to hypoglycemia
Hormone
Response
Insulin
Decreased secretion
Glucagon
Increased secretion
Catecholamines
Increased secretion
ACTH, cortisol, growth hormone
Increased secretion
Source: Feldman EC, Nelson RW. Beta-cell neoplasia: insulinoma. In: Canine
and Feline Endocrinology and Reproduction, 3rd edition, p. 618. St. Louis,
MO: Elsevier Science; 2004.
Table 2.5.5 Clinical signs of insulin-secreting tumors in dogs
Sign
Percentage (%)
Seizures
56
Weakness
47
Collapse
30
Ataxia
19
Muscle tremors
18
Hind end weakness
16
Behavior changes
12
Source: Feldman EC, Nelson RW. Beta-cell neoplasia: insulinoma. In: Canine
and Feline Endocrinology and Reproduction, 3rd edition, p. 621. St. Louis,
MO: Elsevier Science; 2004.
Table 2.5.6 Causes of hypoglycemia
Insulin-secreting tumor
Paraneoplastic
Hypoadrenocorticism
Hepatic failure–PSS, acquired
Toxic–xylitol
Sepsis
Toy breed/fasting puppy
Sampling artifact