Late-Onset Calcinosis Cutis in a Patient with Juvenile Dermatomyositis: An Uncommon Treatment Challenge

Presentation Number: SAT 304
Date of Presentation: April 1st, 2017

Spandana Brown* and Laila Tabatabai
Houston Methodist Hospital, Houston, TX

Abstract

Background:Calcinosis cutis (CC) is commonly seen in juvenile dermatomyositis (JDM) and typically presents 1-3 years from diagnosis. However, late presentation of CC in adulthood is rare and portends more difficulty with management.

Case: A 28-year female with a past medical history of JDM diagnosed at the age of 18 was referred to endocrinology clinic for progressive CC and low bone density. She noticed subcutaneous nodules 2 years prior to presentation along her medial thighs, ankles and right upper calf. Despite control of her JDM with cyclosporine and IVIG, she continued to have progressive calcinosis in her lower extremities without skin ulcerations or joint involvement. Her initial lab values showed a calcium 10.2 mg/dL (8.6-10.5 mg/dL), phosphate 4.2 mg/dL (2.4-4.2 mg/dL) , PTH 20 pg/mL (12-65 pg/mL) and 25-OH vitamin D 69 ng/mL (>30 ng/mL). At 3-months she was unable to tolerate higher doses of diltiazem due to side effects and stopped this medication 1 month later. Additionally, she developed new nodules on her left calf. At this time, she was started on IV pamidronate daily for 3 days every 3 months for 1 year. As it was difficult to assess the patient’s CC progression based on her subjective reports, we proceeded to obtain CT imaging to objectively quantify her calcium burden, including smaller nodules which were not yet causing symptoms. Baseline CT imaging of her lower extremities confirmed lower-extremity subcutaneous calcium deposition and quantified total soft-tissue calcium volume at 4.28 cm3 (N 0.0 cm3). At 11 months, IV pamidronate was discontinued because her lesions continued to progress. She was restarted on a lower dose of diltiazem and colchicine which she tolerated well. Lab studies at this time showed slightly elevated phosphorus level of 4.3 mg/dL and 25-OH vitamin D of 70 ng/mL. She was advised to limit dairy product intake to 2 servings daily and consume non-vitamin D fortified foods. However, despite these interventions, she developed rapidly-progressing pain behind her left knee and ultrasound imaging revealed calcification of the semimembranosus and semitendinosus tendons. Repeat CT showed 126.7% increase in lower-extremity calcium volume. Referral was made to orthopedic surgery for intervention.

Conclusion: The management of CC is extremely challenging, especially when it develops later in the course of JDM. There are currently no uniformly effective regimens to treat this debilitating condition. Medications including bisphosphonates, calcium-channel blockers, sodium thiosulfate and others may be effective, but results vary widely. Surgical intervention is necessary when calcifications cause severe pain or limit mobility. Additionally, to our knowledge, ours is the first case in which radiologic quantification of calcium volume was performed in a patient with CC secondary to JDM; this may serve as an effective method to monitor response to treatment.

 

Nothing to Disclose: SB, LT