Hypercalcemia in Dogs
In the neck, just behind the thyroid gland, are four parathyroid glands responsible for secreting the hormone essential for regulating calcium and phosphorus levels in the body. Through the intricate interactions of parathyroid hormone and vitamin D, calcium is released from the bones, gut, and kidneys into the bloodstream. However, disruptions in these interactions or the secretion of interfering hormones by cancerous cells can lead to hypercalcemia, characterized by an unusually high level of calcium in the blood. A dog is considered hypercalcemic when its total serum calcium exceeds 11.5 mg/dL.
Symptoms and Types
- Elevated urination
- Heightened thirst
- Loss of appetite (anorexia)
- Vomiting
- Reduced gastrointestinal activity
- Constipation
- Fatigue/lethargy/lack of energy
- Confusion
- Depression
- Swollen lymph nodes (neck swelling)
- Formation of bladder stones
- High blood pressure (hypertension)
- Stupor and coma in severe instances
Causes
- Abnormal or excessive activity of the parathyroid gland (hyperparathyroidism)
- Presence of cancer or tumors
- Conditions causing bone deterioration
- Sudden or chronic kidney failure
- Insufficient function of the adrenal glands
- Vitamin D poisoning, stemming from rodenticides, plants, or food (including supplements)
- Toxicity due to aluminum
Diagnosis
Your vet will conduct a thorough physical examination along with a blood chemistry profile, complete blood count, and urinalysis. While elevated serum calcium levels are crucial for diagnosing hypercalcemia, the results of other tests will help determine its underlying cause.
Radiographs and ultrasound imaging may also aid in diagnosing associated conditions like kidney disease, bladder stones, or cancer. Fine needle aspirates from the lymph nodes and bone marrow can be utilized to diagnose lymphoma or blood cancer.
Treatment
Upon diagnosing hypercalcemia in your dog, your veterinarian will likely recommend hospitalization for fluid therapy. Once the underlying condition is identified, your dog will receive the necessary medication(s). Your veterinarian will monitor your dog’s serum calcium levels twice daily throughout its hospital stay until calcium levels normalize.
Living and Management
Your veterinarian will establish a schedule of follow-up appointments for your dog based on the underlying cause of the hypercalcemia.