RESUMEN
Patients with systemic lupus erythematosus(SLE) are at increased risk for infection. Insufficiency of the reticuloendothelial system caused by either immunosuppressive therapy or inadequate opsonization is the mechanism that Salmonella infections in particular appear in these patients. Salmonella infections can provoke a polyarticular reactive arthritis while septic arthritis caused by Salmonella is monoarticular. We report a rare case of septic arthritis caused by Salmonella Group D in a patient with systemic lupus erythematosus. A 20-year-old female patient with systemic lupus erythematosus admitted with a painful swelling of right knee joint. The culture of synovial fluid obtained by aspiration yielded growth of Salmonella Group D. With trimethoprimsulfamethoxazole, the patient was recovered completely.