Long-term Childhood Lupus Nephritis Outcomes Appear to Be Improving

New data suggest that outcomes for children with lupus nephritis (cLN) have improved in recent years thanks to better immunosuppression and medication adherence, as well as careful drug tapering.

Writing in Kidney International Reports, the authors explained that 10% to 20% of people with systemic lupus erythematosus (SLE) develop the condition during childhood. One study in the United States suggested that a third of people with childhood-onset SLE will develop LN, although the incidence of SLE and LN varies significantly among regions.

Immunosuppressive therapies have helped improve outcomes for some patients with LN, but the study authors said the response rates in children with LN have been suboptimal, with a mortality rate of up to 9% and 14% of children with cLN developing end-stage kidney disease (ESKD).

Still, they said there are relatively little outcome data related to cLN, and most of the available data are based on short follow-up times (5 to 6 years). In their new study, the investigators wanted to get a longer-term view of cLN cases to see how recent advances may have changed outcomes.

They retrospectively analyzed 92 cases of biopsy-proven cLN in patients who experienced disease onset at age 18 years or younger. Seventy-eight of the patients were female, their median age was 13.7 years, and all of the patients were Chinese.

Eighty-three of the children had proliferative LN. Mycophenolate (36%) and cyclophosphamide (34%) were commonly used as induction therapy, and 55% of patients were given mycophenolate as maintenance immunosuppression.

After 6 months, the researchers said, 65% of patients had complete remission and 20% had partial remission. By 12 months, the complete remission rate increased to 78% and the partial remission rate fell to 8%.

The development—or lack thereof—of chronic or ESKD had a major impact on patient survival. In those without advanced chronic kidney disease (CKD) or ESKD, the 1-year survival rate was 96.7% and the 20-year survival rate was 83.2%.

Overall, 3 patients developed ESKD during the study period, and 5 had CKD. Factors that predicted advanced CKD, ESKD, or death were severe kidney failure requiring dialysis at presentation, nonresponse after 12 months of treatment, and multiple nephritis flares, the authors reported.

Only 2 patients in the study cohort died. One died of pneumonia, while the other died of active severe lupus with macrophage activation syndrome and cerebral involvement.

“Both episodes were unrelated to ESKD but secondary to infection or extra-renal manifestation,” the authors said. “This highlights the importance of ensuring a delicate balance in immunosuppression associated with inadequate disease control and fatal infective complications.”

Although the study investigators said their data were positive, particularly compared with that from previous decades, they added that the cLN mortality rate in other studies remains in the 6%-to-9% range, which they said is far too high.

They concluded that their study suggests that children with LN can expect “fairly promising” long-term outcomes, provided they adhere to their treatment regimens. While complications like infections and steroid toxicities can occur, the authors said those complications are not significantly different from other pediatric patients.

Reference

Chan EY-h, Yap DY-h, Wong W-t, et al. Long-term outcomes of children and adolescents with biopsy-proven childhood-onset lupus nephritis. Kidney Int Rep. Published online October 21, 2022. doi:10.1016/j.ekir.2022.10.014