Background biological agents are now widely used in clinical practice for the treatment of chronic cutaneous, rheumatic and gastro-intestinal inflammatory diseases. Various cutaneous lesions have been described in the patients receiving these biologics (including infections, paradoxical psoriasis or tumoral lesion). The development of depigmenting disorders is an unusual event under these treatments.
Objectives to describe the characteristics of the patients developing a depigmenting skin disorder while receiving a biological agent for the treatment of psoriasis, inflammatory bowel disease (Crohn's disease-CD- or ulcerative disease) or inflammatory rheumatic disease (rheumatoid arthritis-RA-, ankylosing spondylitis-AS- or psoriatic arthritis).
Methods a call for observations of new cases of vitiligo following biological (anti-TNFa, rituximab, tocilizumab, abatacept, anakinra, ustekinumab) treatment was sent to the members of the French specialist networks “Resopso” (dermatologist), “Club Rhumatismes & Inflammation” (CRI) (rheumatologist and internal medicine) and “groupe d'étude thérapeutique des affections inflammatoires du tube digestif” (GETAID) (gastro- enterologist).The skin lesion has to be confirmed by a dermatologist. The current and previous biological agents were recorded.
Results 10 cases were reported during a six month period: 8 M, 2 F, mean age 38.2±11.5 years. The underlying condition requiring a biological agent was plaque psoriasis in 5 cases, AS in 3 cases, RA in 1 case and an association of RA and CD in 1 case. They all had new onset non segmental vitiligo (achromic patches involving the face, hands, chest or back), excepting leucotrichia (lashes and brows) in one case. 7 patients received adalimumab, 1 infliximab, 1 ustekinumab and 1 secukinumab. The mean delay between biologic agent initiation and development of hypopigmentated lesions was 17.4±15.8 months. This was the first line of biologics in 8 cases. Laboratory testing ruled out thyroid disease.The biological agent was maintained in 7 cases, without worsening of hypopigmentated lesions while it was stopped and switched to etanercept in 2 cases and adalimuamb in one case. Excepting dermocorticosteroids, no specific treatment was given for the hypopigmentation.
Conclusions experimental evidences have shown that TNF-α may play a role in the pathogenesis of non segmental vitiligo, and successful cases of vitiligo treated with TNFα inhibitors have been reported. However, a vitiligo may occur during a biological treatment. In this series, anti TNFα was the main (but not exclusive) biologic class associated with this event. Only non segmental vitiligo was observed allowing the maintenance of the treatment. Concomitant occurrence of vitiligo and inflammatory disease such as RA, AS or CD, although rare, has been described. On the other hand, the depigmentation may be related to the biological agent and could represent a new paradoxical side effect.
Disclosure of Interest : None declared