BACKGROUND: Non traumatic osteonecrosis also known as  avascular necrosis (AVN),and tuberculous arthritis (TB    arthritis)most commonly present as chronic monoarticular conditions. Corticosteroid intake is known to predispose individuals to the development of these two conditions.                      
In AVN, corticosteroid remains to be the most common cause that leads to a final  common pathway of disrupting    blood supply to segments of bone causing cell death. In TB arthritis, corticosteroid renders  a patient relatively immunocompromised predisposing to this extrapulmonary infection.                                                                                                                                                         
The incidence of tubercular osteonecrosis in a patient with systemic lupus erythematosus is rare. A review of literature only showed one case report of tubercular osteonecrosis diagnosed by aspiration cytology. Since tuberculosis (TB) is a destructive but curable disease, early diagnosis  and  treatment  are essential.
OBJECTIVE: To present a case of tubercular osteonecrosis in a patient with systemic lupus erythematosus treated with anti-Koch's regimen and iloprost infusion.
CASE: A 27-year old Filipino female who was diagnosed with lupus nephritis and underwent three days  methylprednisolone pulse therapy. Lupus nephritis improved  and  was clinically inactive for two years. She  developed insidious onset of intermittent pain on her left knee, associated with swelling for four months with  subsequent right hip pain of one week duration. MRI of the left knee showed osteonecrosis and arthritis. Radiograph of the right hip showed osteonecrosis. She underwent arthrocentesis of the left knee and the synovial  fluid tested positive for tuberculosis by PCR. We started the patient on quadruple anti-Koch's regimen together with iloprost infusion which afforded clinical improvement. 
CONCLUSION: To our knowledge, this is the first reported case of a lupus patient with concomitant polyarticular osteonecrosis complicated by monoarticular tuberculous arthritis. Medical treatment, while it may be complicated by adverse drug events, is effective in symptomatic treatment, but a multidisciplinary approach is suggested for optimal outcome.