Imaging findings in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an unusually complex autoimmune disease that is encountered in every radiology subspecialty because of its multisystem involvement and the wide age range of affected patients. There are no universally accepted diagnostic imaging criteria for SLE, and in fact, many SLE patients present with systemic findings and laboratory abnormalities and do not require imaging. Nevertheless, radiology plays an ancillary role in the diagnosis and management of this often insidious disease, and knowledge of the spectrum of radiologic findings in SLE and its complications is crucial for proper image interpretation. Imaging is often performed in patients with a known diagnosis of SLE to determine the extent and severity of disease, which depend on the extent of organ involvement, and to monitor complications. In addition, imaging may be important in selected patients with diseases such as pneumonia who present with atypical symptoms due to immunosuppressive therapy.