Clinical Images: Cholesterol crystals bursitis.

Abstract

The patient, a 45-year-old woman, was referred to the outpatient clinic with an effusion of her right olecranon bursa. She had a history of systemic sclerosis, liver cirrhosis, and autoimmune hepatitis that was treated with mycophenolate mofetil and prednisone. About 3 years ago, she started to develop an effusion of the right olecranon bursa. More recently she noticed white skin nodules, which turned out to be calcinosis cutis. There were no signs of arthritis on either clinical examination or imaging. An ultrasound of the right olecranon bursa was performed and revealed a tissue mass with hyperechogenic lesions within, which is compatible with crystal depositions (A). Analysis of the aspirate with the polarization microscope indicated the presence of cholesterol crystals (B; left: original magnification × 40; right: original magnification × 10). These crystals usually look like plates of glass, sometimes with a notch out of a corner. They are variably and mildly birefringent. Under polarized light, they may exhibit a stained-glass effect. Most cases of cholesterol crystals are associated with hyperlipidemia, yet our patient had normal lipoprotein levels and did not use cholesterol-lowering medication. Instead, increased local cell degeneration and/or increased lipid permeability in response to chronic inflammation might have contributed to the formation of cholesterol crystals in the olecranon bursa of our patient. Cholesterol crystals have been described previously just once in a patient with scleroderma, in the subcutis, mimicking calcinosis cutis (1). After failing local corticosteroid injections, the patient was finally referred to the orthopedic surgeon for surgical synovectomy. Cholesterol crystals in bursal fluid of a patient with scleroderma has not been previously reported, as most of the cases reported so far in patients with rheumatic diseases are concerning patients with rheumatoid arthritis (2). Disclosure Form Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.