Abstract Background Systemic lupus erythematosus is a chronic autoimmune disease characterized by immune complex deposition in various organs and autoantibodies against nuclear antigens. Gastrointestinal involvement is a common complication in systemic lupus erythematosus, affecting many patients, often asymptomatically. While serositis is a common manifestation of systemic lupus erythematosus, peritoneal involvement, particularly as the initial symptom, is rare. Case presentation A 37-year-old Syrian housewife presented with chronic painless abdominal distension, pain in the left leg accompanied by non-pitting edema, and a productive cough. Initial evaluation revealed right pleural effusion on chest imaging and ascites on abdominal ultrasound and computed tomography. Paracentesis demonstrated yellowish, predominantly lymphocytic fluid with a low serum ascites albumin gradient 1 and low total protein (1.71 g/dL), while peritoneal biopsy indicated mild chronic nonspecific peritonitis. Routine laboratory tests, including liver function and 24-hour urine protein, were unremarkable. Given the clinical picture and serological findings, specifically a positive anti-double-stranded DNA antibody in the context of pleural effusion, the diagnosis of systemic lupus erythematosus was established on the basis of the American College of Rheumatology criteria. The patient was treated with hydroxychloroquine (200 mg/day) and low-dose prednisolone (5 mg/day), resulting in significant clinical improvement with resolution of ascites, while her leg symptoms improved with apixaban (10 mg/day) and enoxaparin (60 mg/day for 2 days) use. On follow-up, full recovery was achieved, and the patient remained asymptomatic. Conclusion This case underscores the atypical and challenging presentation of systemic lupus erythematosus, emphasizing the necessity of considering a broad spectrum of potential diagnoses in cases of unexplained ascites, particularly recognizing systemic lupus erythematosus as a diagnosis of exclusion.
Muhammad et al. (Tue,) studied this question.