Secondary Hyperparathyroidism Symptoms in Cats

Secondary hyperparathyroidism in cats occurs when cats don't receive enough calcium or phosphorus in their diets. This disorder is most common in kittens who are fed a diet consisting entirely of organ meats. Organ meats don't contain the minerals cats need for good health. Secondary hyperparathyroidism can also occur in older cats as a result of chronic kidney failure.

Hyperparathyroidism Explained

Hyperparathyroidism occurs when your cat's parathyroid glands produce too much parathryoid hormone (PTH). The parathyroid glands are located in the throat, adjacent to the thryoid glands on either side of the windpipe. The hormone these glands secrete is responsible for maintaining adequate blood levels of calcium, phosphorus and vitamin D. When these glands secrete too much PTH, hyperparathyroidism occurs; blood levels of these essential mineral fall, and your cat could suffer from serious metabolic dysfunction.

There are two kinds of hyperparathyroidism. Primary hyperparathyroidism occurs when there is an injury to or an abnormality in the parathryoid glands themselves. Secondary hyperparathyroidism usually occurs when your cat's diet doesn't contain the right balance of minerals; this type of secondary hyperparathyroidism is usually seen in young kittens who are fed exclusively on organ meats. Older cats can develop secondary hyperparathyroidism as a result of chronic renal failure.

Symptoms of Secondary Hyperparathyroidism

If your kitten is suffering from nutritional secondary hyperparathryoidism, he'll suffer from abnormal bone growth, bone loss, and deformities of the bones and joints. He may appear reluctant to stand up or move and he may have trouble walking. Kittens with nutritional secondary hyperparathyroidism often display a wide legged stance. Their bones fracture easily and skeletal deformities could be visible. 

If your older cat develops secondary hyperparathyroidism as a result of chronic renal failure, he could display the symptoms of both conditions. Symptoms of hyperparathyroidism include:

  • Vomiting
  • Muscle loss and weakness
  • Lethargy and depression
  • Excessive urination and thirst
  • Lack of appetite
  • Constipation
  • Stiffness of gait
  • Blood urine or difficulty urinating

If your cat has renal failure, he could begin to lose his teeth. The quality of his coat will decrease and he may develop bad breath and ulcers or lesions inside the mouth. These symptoms will worsen progressively with time.

Treating Secondary Hyperparathryoidism in Cats

If the cause of your cat's secondary hyperparathyroidism is nutritional, then treatment will involve placing him on a balanced diet. Most cats recover quickly from nutritional secondary hyperparathyroidism once they're placed on a balanced diet. However, any skeletal deformities they may have sustained will remain permanent.

If your cat's secondary hyperparathyroidism is the result of chronic kidney failure, your cat will need treatment for his kidney disease in order to resolve the symptoms of hyperparathyroidism. Your vet will change your cat's diet and may administer medications to help control levels of calcium, phosphorus and other crucial minerals in your cat's blood. Your cat may need nutritional supplements as well as regular treatments such as dialysis to help control the symptoms of his renal disease.