Objective: To characterize the multisystem chronic inflammatory phenotype, dermatopathologic features, and response to therapy with interleukin 1 receptor antagonist (anakinra) in patients with mutations in the CIAS-1/NALP3 gene.
Design: Retrospective review of medical records and evaluation of histologic findings.
Setting: The National Amyloidosis Centre, London, and a tertiary referral clinic for urticaria.
Patients: Twenty-two individuals from 13 families with autoinflammatory disease associated with CIAS-1/NALP3 mutations.
Main outcome measures: Phenotype, genotype, skin histologic findings, and response to treatment with anakinra.
Results: Five heterozygous missense mutations were identified in CIAS-1/NALP3. Skin histologic findings revealed marked vascular dilatation and neutrophilic infiltration involving small vessels and eccrine glands. Serologic evidence of intense inflammation was present in untreated patients, with median serum amyloid A protein and C-reactive protein levels of 141 and 38 mg/L, respectively. Fifteen patients received anakinra for up to 39 months, all of whom achieved serologic remission and complete resolution of fever, rash, conjunctivitis, and rheumatic symptoms, without any adverse effects. Six patients had AA (reactive systemic) amyloidosis, 2 of whom died of renal failure complications before interleukin 1-inhibiting therapy was available; 1 patient underwent renal transplantation and remains clinically well taking anakinra, and in the remaining 3 patients, anakinra therapy resulted in remission of their nephrotic syndrome.
Conclusions: Anakinra therapy was well tolerated and has sustained efficacy on dermatologic and rheumatic manifestations in these patients with CIAS-1/NALP3 mutations. This treatment also resulted in resolution of AA amyloidosis-associated nephrotic syndrome in all affected patients.