Calcinosis refers to hardened lumps or sheets of calcium deposits under the skin in fatty tissue or muscle. It has been estimated that about 30 percent of children with juvenile dermatomyositis (JDM) develop calcinosis. Doctors do not fully understand why only some children develop calcinosis but they recognize that in many cases children had longer delays between disease onset and the start of treatment or treatment that was not aggressive enough to effectively prevent calcinosis from developing.

Calcium deposits range in size from as small as a pebble to as large as a grapefruit. Deposits can be small nodules or lumps or like sheets, and the size and shape can change over time. Depending on the location of the deposits, children might feel tenderness or pain.

Doctors can see larger calcifications using a standard x-ray but require the more sensitive computed tomography (CT or CAT scan) to see smaller or deeper deposits.

Once calcium deposits develop, they are difficult to treat. Doctors agree that initial aggressive therapy to control the inflammation and other disease processes is key. Medicines used to treat the underlying myositis have produced a decrease in calcinosis in some cases, but these are doctor-reported cases and not results of controlled clinical trials. Diltiazem, a medicine that blocks calcium from entering cells, has had positive results in anecdotal reports but brings with it certain side effects. Bisphosphonates, medicines used to treat osteoporosis, have also been considered.

Physical therapy can help children increase their range of motion when their joints are contracted (contractures). Surgery is an option when children experience severe pain, loss of mobility, or chronic infections.

Note: Many parents ask if taking calcium supplements is inappropriate due to the excess calcium depositing. Calcium supplementation does not affect these deposits as the supplemented calcium is absorbed by the bone and does not add to the calcium deposit.

Updated March 2007