[Active WHO class IV lupus nephritis in a patient treated with etanercept for a psoriasic arthritis].

INTRODUCTION: Drug-induced lupus nephritis in patients treated with TNF α inhibitor is a rare adverse effect. Anti-TNF α therapies are commonly associated with the induction of auto-antibodies, whereas anti-TNF α-induced lupus is rare, most frequently involving arthritis and cutaneous lesions. However, several renal involvement has been reported.

OBSERVATION: A 26-year old woman with a history of psoriasic arthritis treated with TNF α inhibitor (etanercept) presented with a biopsy-proved class IV lupus nephritis. The diagnosis of drug-induced lupus nephritis was probable and anti-TNF α therapy was discontinued. Standard lupus nephritis therapy was then started with prednisolone pulses and mycophenolate mofetil (MMF). Two weeks later, a septic shock following a leg cellulitis was caused by Pseudomonas aeruginosa and had a fatal evolution despite MMF withdrawal, adapted antibiotherapy and large wound excision.

DISCUSSION: Our therapy was not different than for other class IV lupus nephritis. Our observation highlights two points: first the attributability to etanercept in lupic manifestations in our patient and second the therapeutic strategy in this particular case of drug-induced lupus.

CONCLUSION: We reported a possible first case of IV lupus nephritis induced by anti-TNF α with a fatal evolution.