Resolution of calcinosis using bisphosphonates in overlap syndrome - a case report.

Introduction: Calcinosis cutis is a common complication of pediatric rheumatologic diseases. However, there is currently no consensus on first-line treatment. Bisphosphonates have been described as a successful treatment in several case studies, but most of these cases are limited to patients with isolated juvenile dermatomyositis or systemic sclerosis. Specifically, there are limited reports of their usefulness in treating overlap syndromes and mixed connective tissue disorders.

Case Presentation: We describe the case of a 13 year-old girl with overlap syndrome with features of juvenile dermatomyositis and systemic lupus erythematosus. After 22 months of extensive immunosuppressive therapy, including monthly IVIG and Rituximab, she continued to have pain and weakness of the lower extremities. A CT scan was performed which showed significant multifocal soft tissue calcifications of the pelvis. She was started on treatment with oral alendronate with the goal of improving her calcinosis and improving her symptoms. After several months of therapy, our patient reported subjective improvement of her lower extremity pain and weakness, as well as complete resolution of abnormalities previously seen on physical examination. A repeat CT scan of the pelvis was performed after 11 months of therapy and demonstrated complete resolution of the previously seen calcinosis.

Conclusions: We report the successful treatment of soft tissue calcinosis with oral bisphosphonates in a patient with juvenile dermatomyositis-systemic lupus erythematosus overlap syndrome. These results provide further evidence that bisphosphonates can be used successfully to treat calcinosis cutis in pediatric rheumatologic disorders. Additionally, the results provide new evidence that they can be used specifically in juvenile dermatomyositis-systemic lupus erythematosus overlap syndrome, which has not been previously reported.