Belimumab-induced periungual pyogenic granulomas: A case report.

Pyogenic granuloma (PG) is a benign vascular neoformation, presenting as a painful red nodule on the skin, mucosa or nail apparatus. It is usually related to local complications such as bleedings and superinfections. The etiology of PG remains still unclear, and several triggers can lead to its formation. In case of multiple lesions, systemic conditions and drugs remain the main causes. Antineoplastic treatments, retinoids, antiretrovirals, hormones and anticonvulsants are frequently implicated in PG formation. In literature, PG has been rarely described in the course of biological treatment due to rheumatological disease. The present case report describes the development of polydactolous PGs in a 21-year-old woman with juvenile systemic lupus erythematosus (jSLE) during treatment with belimumab, a monoclonal antibody directed against BlyS. The clinical presentation, in particular the timing and the multiplicity of the lesions, and the improvement after belimumab discontinuation allowed us to consider PG as drug-induced. This case highlights the importance of considering PG as a potential complication of rheumatologic treatments.