Clinicopathological findings, treatment response and predictors of long-term outcome in a cohort of lupus nephritis patients managed according to the Euro-lupus regime: a retrospective analysis in Sri Lanka

Use of EuroLupus Cyclophosphamide Dosing for the Treatment of Lupus Nephritis in Childhood-onset Systemic Lupus Erythematosus in North America

OBJECTIVE

Childhood-onset systemic lupus erythematosus (cSLE) has higher rates of lupus nephritis (LN) than adult-onset SLE, often requiring intensive immunosuppression. This study examined North American practices and preferences for the low-dose EuroLupus cyclophosphamide (CYC) protocol, as compared to the high-dose National Institutes of Health (NIH) CYC protocol, to treat LN in cSLE.

METHODS

A 35-item Web-based survey was distributed to Childhood Arthritis and Rheumatology Research Alliance (CARRA) and Pediatric Nephrology Research Consortium (PNRC) providers. The survey assessed participant demographics, CYC prescribing practices, perceptions of EuroLupus protocol, and LN vignette treatment decisions; 1 vignette was taken from a 2009 CARRA survey and responses were compared. Multivariable logistic regression analyzed provider factors associated with use of low- vs high-dose CYC.

RESULTS

Responses were provided by 185/421 (44%) pediatric rheumatologists (CARRA) and 40/354 (11%) pediatric nephrologists (PNRC). Among respondents who prescribed CYC for pediatric LN over the past year (n = 135), half reported using EuroLupus. When presented with the same vignette about an adolescent with class IV LN, 32% of pediatric rheumatologists chose EuroLupus dosing in 2020, vs 6% in 2009. Provider factors associated with choosing the low-dose regimen were familiarity with the protocol (OR 4.2, P = 0.006) and greater perceived benefit (OR 1.6, P < 0.0001). Pediatric nephrologists had similar responses to the pediatric rheumatology providers. Overall, 78% of respondents perceived EuroLupus protocol efficacy to be equivalent to the high-dose protocol in cSLE LN.

CONCLUSION

Pediatric specialists are currently more likely to use low-dose CYC to treat cSLE LN than they were a decade ago. Nevertheless, familiarity with EuroLupus dosing remains low.

Membrane attack complex (mac) deposition in lupus nephritis is associated with hypertension and poor clinical response to treatment

OBJECTIVE

To study membrane attack complex in lupus nephritis as a potential biomarker for disease intensity and prognostic indicator for response to treatment.

METHODS

Immunohistochemistry was performed using unconjugated, murine anti-human complement C9 on kidney biopsies from 30 SLE patients who fulfilled 4 ACR or SLICC criteria. Clinical parameters were assessed at time of biopsy, 6 and 12 months.

RESULTS

30 renal biopsies were obtained from patients with Class II (2), III (5), IV (8), V (5), III+V (8) and IV+V (2). 13/30 (43.3%) biopsies stained positive for glomerular C9. Patients with positive C9 had significantly higher blood pressure, trend towards lower C3, and male gender. There was no significant difference for ISN/RPN class, activity or chronicity indices between C9 positive and negative groups. 5/11 (45.5%) patients positive for C9 did not respond to therapy at 6 months compared with 2/15 (13.3%) patients negative for C9. C9 positive patients were more likely to be a non-responder at 6 months (OR = 5.4, 95% CI: 0.8, 36.4) compared to C9 negative patients. After adjusting for systolic blood pressure, compliance to treatment and proteinuria in a multivariate logistic model, C9 positive patients remained more likely to be non-responders (OR = 4.6, 95% CI: 0.3, 70.9).

CONCLUSION

This study suggests that MAC deposition measured as C9 staining may be a biomarker for more intense disease and poor response to treatment in lupus nephritis. MAC staining may be useful in routine studies of lupus biopsies and identify patients at risk for aggressive disease who may be candidates for novel therapies targeting terminal complement pathway.