Relapsing Polychondritis in a Patient with Lupus Erythematosus: Another Manifestation of Neutrophilic Lupus?

patients usually have a favourable prognosis of the chondritis [1, 2] . The pathogenesis of RP is not known, and it has been considered as an auto-immune disorder, on the basis of an association with HLA-DR4, and evidence of humoral and cellular responses to cartilaginous components [3] . However, histologically, the inflammatory cell infiltrate initially found in the cartilaginous matrix is predominantly constituted of neutrophils, which are only secondarily replaced by lymphocytes, plasma cells and histiocytes [4] . From an epidemiological point of view, RP shares with neutrophilic dermatoses (e.g. Sweet’s syndrome or pyoderma gangraenosum) the same spectrum of associated diseases: acute and chronic myeloproliferative disorders, myelodysplastic syndromes, inflammatory bowel diseases etc. Besides, coexistence of RP and neutrophilic dermatosis is not rare, and RP is reputed to show clear sensibility to neutrophil-targeting drugs (i.e. dapsone or colchicine). Moreover, high levels of interleukin-8/CXCL8, a potent neutrophil chemotactic factor and a crucial mediator in neutrophil-dependent acute inflammation, are found in serum of patients with RP [5] , consistent with an auto-inflammatory disease pathomechanism. In a precedent issue, Antille et al. [6] reported a well-characterized case of amicrobial pustulosis of skin folds associated with undetermined connective tissue disease, a typical example of ‘neutrophilic cutaneous LE’. Lipsker and Saurat [7] suggested in the same issue the concept of ‘neutrophilic cutaneous LE’ to include all lupus-associated neutrophilic dermatoses. We believe that lupus-associated polychondritis can be seen as another autoinflammatory manifestation of this complex multi-factorial disease, and thus suggest adding this peculiar condition to the new concept of ‘neutrophilic LE’.