Description Systemic lupus erythematosus (SLE) is an autoimmune disease affecting all age groups and can manifest in various forms, often making the initial or successive presentations difficult to diagnose. Peritonitis secondary to lupus is a rare manifestation of this disease and the prevalence is said to be much lower in children. We present a case report of an adolescent male with a known history of lupus who presented to the emergency department with a clinical picture consistent with an acute surgical abdomen and underwent an appendectomy. Subsequent workup identified the culprit as a lupus-related peritonitis requiring corticosteroids for resolution.

This is a case report of 7-year-old boy who presented with diplopia. Physical examination was remarkable for pallor and right-eye proptosis. Differential diagnosis of this chief complaint and the management of the suspected condition are discussed. This case was presented at the Section of Emergency Medicine Meeting at the National Conference and Exhibition of the American Academy of Pediatrics in 2011 and was awarded first place in the PEMpix photo competition.