Klin Onkol 2025; 38(2): 119-127. DOI: 10.48095/ccko2025119.

Background: Schnitzler‘s syndrome is an acquired autoinflammatory disease with a disorder in innate immune response. The suspect is the protein MyD88 – a toll-like receptor involved in the inflammatory cascade resulting in increased secretion of interleukin-1 (IL-1), a key cytokine in the pathogenesis and clinical manifestation of several autoinflammations. The syndrome is named after the French dermatologist Liliane Schnitzler, who described a case series of patients with manifestations of urticaria and monoclonal gammapathy in 1972. The clinical picture is characterized by chronic urticaria, histologically it is most often neutrophilic dermatosis. A necessary criterion for defining Schnitzler‘s syndrome is monoclonal gammapathy. In up to 90% of cases, it is monoclonal IgM gammapathy, the remaining group of patients has IgG gammapathy. Among the secondary criteria necessary to define the syndrome according to the Strasbourg classification, non-specific inflammatory activity is present in patients (elevation of CRP, leukocytosis), morphological changes on the bones (hyperostotic or osteosclerotic changes of the skeleton verified by CT, scintigraphy or PET/CT using radioactive sodium fluoride NaF18), bone pain or arthralgia. Patients are at an increased risk of developing a lymphoproliferative disease, especially Waldenström‘s macroglobulinemia or low grade lymphoma (15–20%). There is also a risk of the development of AA amyloidosis due to long-term uncontrolled hyperinflammation. Macrophage activating syndrome can be an acute life-threatening complication, as we describe in our patient. Considering the immunological nature of the disease and the elevation of inflammatory cytokines, the basis of treatment is anticytokine therapy. The best results are seen with anakinra (IL-1 receptor antagonist), possibly canakinumab (a monoclonal antibody against IL-1b). A positive effect was also described with Bruton‘s tyrosine kinase inhibitors. Corticoids and conventional immunosuppressants are not effective enough. Case: In this text, we present a case series of two patients with Schnitzler‘s syndrome with rare clinical symptoms. The authors‘ goal was to improve awareness of this rare hematoinflammatory disease and its treatment options. Conclusion: The disease is chronic, the treatment is only symptomatic, but can lead to the reduction of clinical symptoms. Anticytokine treatment probably does not affect the risk of hematological malignancy.

http://dx.doi.org/10.48095/ccko2025119

Full text in PDF