Calcinosis circumscripta is a disorder of calcium metabolism marked by partial localized calcium deposition. It has a cystic structure and contains calcium phosphate or calcium carbonate. It is also known as tumoral calcinosis, apocrine cystic calcinosis and calcium gout. The condition is characterized by the formation of nodules (small lumps) on pressure points, over bony prominences, in the tongue, spine, salivary glands, aorta, and on the foot pads. The nodules occur as round, non-painful masses which, when cut open, discharge a chalk-like substance. On footpads, they can cause progressive lameness.
Colonies of bacteria on agar plate and their ability to encrust themselves in calcium carbonate
Source: Dick et al., 2006, CDC
The disease is classified into 3 groups: dystrophic, idiopathic, and metastatic. Idiopathic calcinosis is commonly seen in the young German Shepherd Dogs, Rottweilers and Labrador Retrievers, but small breeds also can be affected. Although the exact cause of calcinosis circumscripta remains unknown, numerous causes and associated disorders have been suggested, which include:
- Administration of commercially available medroxy-progesterone acetate and the use of sutures with calcium chloride
- Vitamin D intoxication
- Chronic kidney failure. Most reported pad lesions of calcinosis circumscripta are due to kidney failure.5
- Nutritional myopathy
Calcinosis circumscripta on the tongue of a dog may look like a raised and irregular yellowish-pink nodule, while on digits an ulcer may be present in the center of the lesion.
Diagnosis is based on histological examination of affected tissue. The conventional treatment of calcinosis circumscripta involves surgical removal and is usually curative. In some cases, lesions have been observed to resolve on their own. An oral charcoal adsorbent (Kremezin) has been reported to be effective. Following this treatment, a significant decrease in the serum calcium level x the serum phosphorus level is observed, and dogs improve dramatically.1
- Metastatic calcinosis circumscripta treated with an oral charcoal absorbent in a dog. Komori S, Washizu M. In: J Vet Med Sci. 2001 Aug;63(8):913-6.
- Veterinary Dermatopathology. Thelma Lee Gross. Published by
Blackwell Publishing, 2004 ISBN 0632064528, 9780632064526
- Calcinosis Circumscripta on Lingual Muscles and Dermis in a Dog. Jeong W, Noh D, Kwon OD, Williams BH, Park SC, Lee M, Do S, Chung J, Lee G, Yun H,
Jeong KS. In: J Vet Med Sci. 2004 Apr;66(4):433-5.
- Calcinosis circumscripta following an injection of proligestone in a Burmese cat. In: Australian Veterinary Journal. Volume 79 Issue 3. DOI:
- Skin Diseases of the Dog and Cat: Clinical and Histopathologic Diagnosis. Thelma Lee Gross, Peter J. Ihrke, Emily J. Walder, Verena K. Affolter