Letter to the Editor Palindromic Rheumatism Associated with Primary Hypertrophic Osteoarthropathy

Hypertrophic osteoarthropathy (HOA) is a syndrome characterized by the triad of finger clubbing, periosteal new bone formation, skin and soft tissue changes, giving an acromegaloid look. It is present in 2 distinct syndromes: primary and secondary. The former is a rare inherited disorder occurring predominantly in males and not associated with any known disease process. The secondary syndrome is acquired and often associated with malignancy, especially lung carcinoma. Rarely, it can also be associated with nonmalignant disorders, such as chronic liver disease, inflammatory bowel disease, cyanotic heart disease and other forms of shunts (cavernous hemangiomas and arteriovenous fistulae, sarcoidosis, and pulmonary tuberculosis. If the underlying disease is correctable, the musculoskeletal manifestations may resolve, suggesting a humoral factor. Both types may be associated with peculiar skin changes known as pachyderma, characterized by thickened, furrowed skin. When idiopathic HOA is associated with pachyderma, it is called pachydermoperiostosis. In extremely rare instances, it may occur without pachyderma, possibly representing a nosologically distinct form of osteoarthropathy. Palindromic rheumatism is a recurrent or relapsing oligoarticular arthritis of short duration with periand paraarticular tissue inflammation, resulting in no residual clinical or radiographic changes. Hench and Rosenberg first used the term in 1944 to describe 34 patients with recurrent, short-duration polyarthritis. In the long term, a substantial proportion of patients with palindromic rheumatism will go on to develop rheumatoid arthritis or other connective tissue diseases (eg, systemic lupus erythematosus, Wegener granulomatosis, or spondyloarthropathies), but the determinants of subsequent chronic disease have not yet to been well established. Positive rheumatoid factor in females and early involvement of the wrist and proximal interphalangeal joints predict subsequent development of rheumatoid arthritis of other connective tissue disease in patients with palindromic rheumatism. Besides crystal arthritis, there are several diseases that may be clinically similar to palindromic rheumatism, such as systemic autoinflammatory disorders (periodic fever syndromes), Whipple ́s disease, arthritis associated with hyperlipidemia, and intermittent hydrarthrosis. In the present work, we report an unusual case of a Brazilian male patient with palindromic rheumatism manifested in association with primary HOA without pachyderma. Disease activity was controlled with diphosphate chloroquine combined with methotrexate, leading to remission of arthritis relapse.