Systemic lupus erythematosus (SLE) is a chronic, multi-organ autoimmune disease which rarely presents with peritoneal involvement. As such, its diagnosis in the emergency department (ED) based on a clinical presentation of gastrointestinal symptoms is extremely challenging. Yet, reaching such a diagnosis in the ED is crucial for avoiding unnecessary surgical intervention and initiating early glucocorticoid therapy to maximise patient outcomes. Here, we report a case of newly diagnosed SLE in a 28-year-old lady who presented atypically and unusually with abdominal pain and ascites. She required extensive but methodical investigations, and was eventually diagnosed with lupus mesenteric vasculitis with underlying newly diagnosed SLE in the ED. The patient was promptly treated with methylprednisolone resulting in marked clinical improvement. Emergency physicians should be mindful of abdominal pain with ascites as an extremely rare but important clinical presentation of SLE. Early diagnosis and commencement of glucocorticoid therapy in these patients are crucial in halting disease progression and averting the need for surgical intervention.
Keywords: Systemic lupus erythematosus; anti-double stranded DNA; comb sign; emergency department; lupus mesenteric vasculitis; serum-ascites albumin gradient.