Relapsing polychondritis associated with pustular psoriasis successfully treated with secukinumab: a case-based review

Abstract
Rationale
Relapsing polychondritis (RP) is an immune-mediated systemic inflammatory disease involving cartilage and proteoglycan-rich tissues. Pustular psoriasis (PP) is a psoriasis subtype characterized by skin erythema and sterile pustules. In previous studies, there were few reports on patients with RP combined with psoriasis, and treatment strategies are not standardized.

Patient concerns
An 80-year-old Chinese woman with a 7-year history of atrial fibrillation, a 1-year history of coronary atherosclerotic heart disease, and no familial history, had a 2-month history of skin rash, erythema, swelling and pain in both hands, swollen bilateral auricles, and fingertip gangrene.

Diagnosis
Based on the diagnostic criteria for generalized pustular psoriasis proposed by Fujita et al. in 2018 and RP proposed by McAdam et al. in 1975, we diagnosed RP with PP as the predominant manifestation.

Interventions
We started therapy with subcutaneous secukinumab 150 mg weekly for the first month, then 150 mg monthly thereafter.

Outcomes
After 2 weeks of secukinumab administration, the patient showed significant remission of pustular skin lesions, with almost no joint pain, swollen bilateral auricles, and no adverse reaction.

Conclusions
Pustular lesions secondary to RP-associated gangrene and swollen auricles were observed, demonstrating a potential immune correlation between RP and psoriasis in some patients. Although data related to the use of secukinumab for RP and PP is very limited due to the rarity of the two conditions presented together, secukinumab provides a novel therapeutic option. Further prospective studies are needed to support our findings.