Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease that may affect any organ of the body. We report here an unusual case of seronegative SLE presented as vasculitis with rash, lower gastrointestinal system bleeding and acute renal failure. The patient was a 13-year-old boy, with abdominal distention, pretibial edema, arthritis and petechia on bilateral ankles. He had deteriorated renal functions (creatinine 1.65 mg/dl), hypoalbuminemia (1.6 g/dl) and hypocomplementemia with nephrotic range proteinuria and hematuria. He developed pleural effusion and peritonitis. Serum ANA, anti dsDNA, p ANCA, c ANCA, anticardiolipin IgM and IgG titers were negative. A renal biopsy was performed which revealed diffuse proliferative glomerulonephritis with full-house staining pattern in immunofluorescent microscopic examination suggesting Class IV Lupus Nephritis. He was administered a total of six courses of monthly intravenous pulse methyl prednisolone, dipyridamole, oral cyclophosphamide followed by azothiopirine and oral prednisolone therapy. The renal functions and serum albumin levels turned normal but peritonitis persisted and disappeared after the third pulse steroid therapy. In conclusion, we presented this patient to remind the possibility of SLE in such seronegative patients with unusual findings in order to avoid the delay in the management of this disease with high mortality and morbidity if not treated. Full-house nephropathy is an important clue especially for the diagnosis of ANA negative SLE.