Systemic lupus erythematosus (SLE) tends to be severe and to have a variable response in childhood. We undertook this retrospective study to assess response rates and outcome in 14 children with SLE. Mean age at onset was 12.8+/-3.1 years. Ten patients were female and 4 were male, and 12 patients (86%) were Hispanic. Creatinine clearance prior to therapy was 104+/-36 ml/min. All had hematuria and proteinuria with a protein/creatinine ratio of 3.9+/-4.8. WHO classification of renal biopsies revealed class IV in 64%, class III in 21%, and class V in 14%. Patients were treated with 6-monthly pulses of intravenous cyclophosphamide (IVCY) followed by longer-duration pulses. The mean duration of follow-up was 3.7+/-3.3 years. Of the 14 patients, 3 (21%) achieved systemic remission but all relapsed subsequently; 7 of 14 achieved renal remission, although 6 relapsed. Six (42%) had adverse outcomes, defined by death, dialysis, or need for bone marrow transplant. All 6 had failed 6 months of IVCY, suggesting that patients who demonstrate resistance to initial IVCY therapy have an unfavorable outcome and a high likelihood of complications. In summary, we report a poor response to standard therapeutic protocols with higher relapse rates, as well as significant adverse outcomes.