Calcinosis Circumscripta
Multiple deposits of calcium are commonly observed in dogs with hyperadrenocorticism. Partial calcium deposition that has a cystic structure and contains calcium phosphate or calcium carbonate is called calcinosis circumscripta and is also known as tumoral calcinosis, apocrine cystic calcinosis and calcium gout. Diagnosis is made via
histological examination of affected tissue. The condition has been reported in humans, horses, and dogs and rarely in cats. This condition was first reported in 1962 and is classified into 3 groups: dystrophic, idiopathic and metastatic calcinosis.
Generally, calcinosis circumscripta presents as one or more
nodules but has also been reported in the tongue, spine, salivary gland and aorta in domestic animals. The nodules (small lumps) occur on pressure points, over bony prominences, on the footpad or in the mouth. The nodules are round, non-painful masses which, when cut open, discharge a chalk-like substance. In rare cases the nodules can develop along the spinal column and put pressure on the spinal cord and in some cases nodules on footpads can cause progressive lameness.
The occurrence of this disease has been reported in connection with the administration of commercially available medroxy-progesterone acetate and the use of sutures with calcium chloride. Dystrophic calcinosis occurs following tissue damage. Idiopathic calcinosis is commonly seen in dogs. The occurrence of this condition is most commonly seen in younger dogs of large breeds, especially German Shepherd Dog, Rottweiler and Labrador Retriever, but small breeds also can be affected. Metastatic calcinosis is associated with high serum calcium or high serum phosphate levels. Primary hyperparathyroidism, vitamin D intoxication, and chronic renal failure are factors that lead to this condition. In dogs, most cases of metastatic calcinosis were associated with chronic renal failure, and the lesion were confined to pawpads, although other cases with lesions in the mouth and intestines have also been reported.[2]
The cause of calcinosis circumscripta remains unknown, however numerous causes have been suggested. Synthetic progestogens are used in the control of oestrus in the bitch and queen, behavioural modification and for a variety of inflammatory skin conditions, especially in the cat. Subcutaneous injections of progestogens have been associated with local alopecia, skin atrophy, pigmentary disturbances and rarely, calcinosis circumscripta in the cat and dog.[4]
Deposition of calcium salts is also found in nutritional myopathy due to a deficiency of vitamin E and/or selenium and in this disease muscle fibers undergo destruction. Calcinosis circumscripta and nutritional myopathy are rare diseases, but have been reported naturally in dogs and cats respectively. On rare occasions, each of them also occurs in the tongue.[3]
TREATMENT
An oral charcoal adsorbent (Kremezin) has been reported to treat this condition. Following this treatment, a significant decrease in the serum calcium level x the serum phosphorus level is observed, and dogs improve dramatically.[1] Treatment of calcinosis circumscripta involves surgical removal and is usually curative. Some lesions have also been
observed to resolve on their own.
Go Pets America recommends seeking the advice of your local veterinarian for the most appropriate vaccination program and for the diagnosis and treatment of your pet's health problems. For vaccination requirements please contact your state and local licensing authorities.
|