Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect multiple organ systems. Key signs and symptoms include malar rash, arthritis, oral ulcers, photosensitivity, serositis, renal disease, and hematological abnormalities. Diagnosis involves evaluating clinical criteria along with identifying autoantibodies. Treatment aims to induce remission during flares using glucocorticoids and immunosuppressants to prevent organ damage.