Etanercept-induced pleuropericardial lupus-like syndrome.

Tumour necrosis factor (TNF)-a is currently being targeted in autoimmune joint diseases, including rheumatoid arthritis (RA) and spondylarthropathies [1, 2]. Widespread use of antiTNF-a therapies (e.g. etanercept) has unveiled a spectrum of adverse effects, including infection [3] and a systemic lupus erythematosus (SLE)-like syndrome [4]. The latter appears to be biologically based on perturbations in TNF-a-controlled homeostasis of interferon (IFN)-a [5], and is betrayed by seroconversion of SLE markers [6]. With interest, we read the occurrence of pleural effusions associated with anti-TNF-a agents [7]. We encountered a patient with RA taking etanercept, who developed alternating pleural effusions. We obtained measurements that suggested that a lupus-like syndrome and not a common drug reaction precipitated these pleural effusions.