Disease severity of proliferative lupus nephritis in Maghrebians

Objective To study the influence of Maghrebian ethnicity on lupus nephritis. Methods We retrospectively reviewed the files of a cohort of 194 patients with proliferative lupus nephritis followed in seven lupus centres belonging to three groups: Europeans living in Belgium/France (E; n = 111); Maghrebians living in Europe, in casu Belgium/France (ME; n = 43); and Maghrebians living in Morocco (MM; n = 40). Baseline presentation was compared between these three groups but complete long-term outcome data were available only for E and ME patients. Results At presentation, the clinical and pathological characteristics of lupus nephritis did not differ between E, ME and MM patients. Renal relapses were more common in ME patients (54%) than in E patients (29%) ( P < 0.01). Time to renal flare and to end-stage renal disease was shorter in ME patients compared to E patients ( P < 0.0001 and P < 0.05, respectively). While proteinuria measured at month 12 accurately predicted a serum creatinine value of less than 1 mg/dl at 7 years in E patients, this was not the case in the ME group, in whom serum creatinine at month 12 performed better. Conclusion Despite a similar disease profile at onset, the prognosis of lupus nephritis is more severe in Maghrebians living in Europe compared to native Europeans, with a higher relapse rate.