Sweet's Syndrome in a Patient With Seropositive Rheumatoid Arthritis After Starting Adalimumab: Is Sweet's Syndrome Related to Rheumatoid Arthritis or Is It the Paradoxical Effect of Adalimumab?

Sweet's syndrome is a rare acute febrile neutrophilic dermatosis accompanied by fever, neutrophilia, and asymmetrical distribution of tender erythematous skin lesions. The underlying biological pathways responsible for this inflammatory skin disorder are not yet clearly established. However, an association with autoimmune disease, neoplasm, and drugs could be indicative of unusual hypersensitivity involving proinflammatory cytokines. There are several case reports indicating an association between Sweet's syndrome and rheumatoid arthritis (RA). Proinflammatory cytokines are considered to play a vital role in the pathogenesis of both RA and Sweet's syndrome. Adalimumab works against proinflammatory cytokines and is considered a disease-modifying antirheumatic drug in RA; it is also reported to be effective in refractory Sweet's syndrome. While adalimumab has been proven to be beneficial in autoimmune disorders and inflammatory conditions, there are also reports of paradoxical development of Sweet's syndrome with adalimumab. In this report, we present a case of Sweet's syndrome in a 74-year-old adult patient with a history of seropositive RA who developed Sweet's syndrome within two months after the initiation of adalimumab therapy.