Purpose: To study the natural history of clinically occult avascular necrosis (AVN) of the hip in patients with systemic lupus erythematosus (SLE), and to identify clinical associations and imaging findings that might accompany this lesion.Methods: Forty SLE patients, without symptoms referable to the hip, and receiving a minimum of 5 mg/day prednisone for > 6 months were screened by MRI for avascular necrosis of the hip. Medical records were reviewed for serologic and clinical variables that might predict AVN. MRI was repeated after 6 months to assess progression in patients with positive MRI, and to detect possible occurrence in patients with negative MRI.Results: Asymptomatic AVN was detected by MRI in 8 (10%) hips of 5 (12.5%) patients. Associated clinical findings with clinically occult AVN included Raynaud's phenomenon, vasculitis, renal affection, disease activity and cumulative dose of steroids.Conclusion: Clinically occult AVN of the hip is common in patients with SLE. It is recommended that MRI should be considered for the early diagnosis of AVN in high- risk patients to prevent or delay progression of the disease.