[Schnitzler syndrome: diagnostics and treatment]. / Schnitzler-syndrom: diagnostika a lécba.

BACKGROUNDS: The most important diagnostic criteria for Schnitzler syndrome include chronic urticaria, the presence of monoclonal IgM immunoglobulin, marked inflammation (leukocytosis, elevated CRP and erythrocyte sedimentation rate), subfebrile temperatures or fevers and bone and joint pains. It is a rare idiopathic disease that may lead to potentially life-threatening complications such as development of secondary amyloidosis or transformation into malignant lymphoproliferation. Schnitzler syndrome should be included in differential diagnostics of chronic urticaria and fevers of unknown origin. The diagnostic algorithm is based on clinical presentation and serum and urine electrophoreses to detect monoclonal components. Blockade of interleukin-1 (IL-1), key cytokine in the pathogenesis of the disease, dominates current therapeutic protocols. Anakinra (Kineret), recombinant human IL-1 receptor antagonist, is the most widely used treatment option. According to literature, disease remission was obtained in all treated patients. Therefore, anakinra represents a significant diagnostic possibility to differentiate Schnitzler syndrome from e.g. monoclonal gammopathy of unknown significance (MGUS) associated with urticaria of different aetiology. Biological therapy with rilonacept (Arcalyst) and canakinumab (Ilaris) represents a new treatment alternative for patients, allowing prolonged dosing intervals of 1 and 8 weeks, respectively (compared to 24 hours with anakinra). The review article also presents findings of various imaging methods (conventional radiography, computed tomography, traditional bone scintigraphy) and photographs of patients with Schnitzler syndrome before and after anakinra therapy. DESIGN: The aim of the review is to draw attention to the existence of this rare autoinflammatory and potentially premalignant condition, present a simple diagnostic algorithm and provide an overview of therapeutic options for the patients. CONCLUSIONS: Malign potential of Schnitzler syndrome, possible development into systemic amyloidosis and the fact that patients are frequently referred to oncology clinics for differential diagnostics of monoclonal gammopathy, are the main reasons why clinical oncologists should be aware of Schnitzler syndrome.

[Schnitzler syndrome: case report, the experience with glucocorticoid and anakinra (Kineret) therapies and monitoring of systemic cytokine response]. / Schnitzler-syndrom: popis prípadu, zkusenosti s lécbou glukokortikoidy a preparátem anakinra (Kineret) a sledování cytokinové odpovedi organizmu.

Schnitzler syndrome is a rare idiopathic disease characterized by chronic urtica, presence of monoclonal IgM immunoglobuline and further, less common symptoms. This case report describes another case of this disease affecting a male adult born in 1963. The first symptoms, eruptions of non-pruritic urticarial rash, appeared in this patient at the age of 43. In addition, bone pains (mainly tibias) and joint pains (mainly knees) were present. Later on however, severe attacks of fever, chills and shaking together with bone and joint pains were added to during which new urticarial eruptions appeared. Primarily, the man was followed up without any substantial therapeutic results at a department of dermatovenerology, subsequently, due to a finding of monoclonal IgM kappa immunoglobulin (serum concentration 1.9 g/l) he was referred to our department for the reason of gammopathy being a differential diagnosis. On a CT scan hyperostosis in claviculae and pelvic bones was identified. Also on the CT, an increase in cortical thickness was described in the long bones of the lower extremities, where areas of technetium pyrophosphate accumulation were identified on a bone scintigraphy. These areas were found in the chest and sacral regions as well. From the blood exams, the proinflammatory status of the organism was apparent (CRP 35.9 mg/l, erythrocyte sedimentation rate 92 mm/h, leukocytes 12.4 x 10(9)/l). After excluding other differential diagnoses, the patient was diagnosed with Schnitzler syndrome. As regards therapy, we made initial use of the effect of corticoids which abated the symptoms, however, these were causing serious adverse reactions in the form of iatrogenous Cushing's syndrome. The therapy took a turn only after biologic therapy with anakinra (interleukin-1 receptor antagonist) had started, which minimized the Schnitzler symptoms with very good drug tolerance. In the work we measured serum levels of interleukins for disease activity monitoring. The most sensitive were interleukins IL-6 and especially IL-18 the levels of which were the highest at the time of clinical exacerbation of the disease, whereas the levels of IL-1beta and TNF-alpha (tumour necrosis factor) were during all measurements below the limit of detection. Concerning the growing numbers of the reports on successful biological therapy with anakinra and our positive experience, we propose that the therapeutic response to anakinra should be included within the diagnostic criteria of Schnitzler syndrome, which is significant above all in differential diagnosis thereof.