Long-term anakinra therapy in Schnitzler syndrome: real-world evidence on remission of neutrophilic dermatitis and systemic inflammation, safety, biomarker insights and dose optimization

IntroductionSchnitzler syndrome (SchS) is a rare, late-onset, acquired autoinflammatory disorder characterized by recurrent urticarial lesions, monoclonal gammopathy and systemic inflammation. Although interleukin-1 (IL-1) blockade with anakinra is considered as a standard of care, real-world data on long-term outcomes, biomarker utility and dose reduction remain limited.

To evaluate the long-term efficacy and safety of anakinra, the utility of inflammatory biomarkers for disease monitoring, the feasibility of dose reduction and diagnostic delay in a cohort of Polish patients with SchS.MethodsWe conducted a retrospective observational study of 13 adults with SchS treated with anakinra at two Polish tertiary referral centers between 2018 and 2025. Clinical manifestations, laboratory parameters, treatment response, adverse events and longitudinal follow-up data were analyzed.

Receiver operating characteristic (ROC) analyses were used to compare biomarkers of disease activity, including serum amyloid A (SAA), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, D-dimers and complete blood count (CBC)-derived inflammatory indices.ResultsAll 13 patients achieved rapid complete clinical remission within 48 hours of starting anakinra, accompanied by significant reductions in CRP and SAA.