New onset weakness in the face and arm

A 32 year old woman with a seven year history of discoid lupus erythematosus (a form of cutaneous lupus erythematosus) was admitted with one week of anisocoria (unequal pupil size), left sided facial weakness, and weakness in her left arm. She had areas of hair loss—a long term sign of her discoid lupus erythematosus—but no other symptoms, infections, toxicological habits, or history of thrombotic events or obstetric complications. Blood tests results are in table 1. View this table: Table 1 Relevant blood test results Her anisocoria and weakness of the face and arm prompted further central nervous system investigations: • Cerebrospinal fluid analysis was normal • Brain computed tomography scan showed bilateral cortical and subcortical frontal lesions of a potentially ischaemic nature • Brain magnetic resonance imaging …