Description Background: Psoriasis is a chronic disease of the skin that often affects joints and IL17 has a pathogenetic role. It has been reported that interleukin-17 (IL-17) and Th17 cells play important roles in the pathogenesis of SLE: amplifies the immune response by inducing the local production of chemokines and cytokines, recruiting neutrophils and monocytes, augmenting the production of autoantibodies, and aggravating the inflammation. Secukinumab is an anti-IL17 monoclonal antibody with approval for use in AS and Psoriatic arthritis. There are few reports on interleukin-17-targeted therapy in SLE. Objectives: We report a case SLE overlapped with psoriatic arthritis, successfully treated with Secukinumab.

Methods 32 y.o.man diagnosed with psoriasis on 2016, started having arthralgia on 2018 simultaneously with a new facial rash. Skin biopsy revealed lupus erythematosus tumidus. Gradually he developed fatigue, photosensitivity, low back pain and arthritis of hand, feet hip joints. Laboratory profile: ANA 1/160 homogeneous, antidsDNA neg, C3, C4 normal, lupus anticoagulant positive, all the other autoantibodies negative.

X-rays showed MCP MTP hand DIP stenosis, and sacroilitis. PASI score 3

First he was treated with Plaquenil and Medrol with improvement in lupus rash and failure both in arthritis and psoriasis. We then added methotrexate and subsequently cyclosporine but all combinations failed to control arthritis.

Results After one year of treatment failures we offered him a combination of Plaquenil, sc Methotrexate and Secukinumab 300 mg/4 weeks. After six months with Secukinumab treatment SLE is inactive and psoriatic arthritis has low disease activity. PASI score 1. No adverse events were observed in terms of SLE.

Conclusions Although recent studies have begun to shed light on the role of IL-17 in the pathogenesis of SLE, there is no experience in real world yet. This case report adds on to our experience on results and safety of Secukinumab in Lupus.