Central skeletal sarcoidosis: a case report with sustained remission only on methotrexate, and a literature review on the imaging approach, treatment, and assessment of disease activity.

We report a case of multifocal involvement of the central skeleton in a patient with long-term stage I pulmonary sarcoidosis who experienced sustained clinical remission of musculoskeletal symptoms while on methotrexate (MTX) alone. Concomitant normalization of laboratory tests [inflammatory markers and angiotensin-converting enzyme (ACE) levels] was observed, and improvements were seen in follow-up magnetic resonance imaging (MRI) of the lumbar spine and bone scintigraphy. To date, there are no specific tools for the assessment of skeletal disease activity in sarcoidosis. Our case suggests that inflammatory markers and ACE levels, when initially elevated, bone scintigraphy, and-in the case of vertebral involvement-MRI could serve as such tools. A literature review on the imaging approach, treatment, and disease activity monitoring of skeletal sarcoidosis is also provided.