The Schnitzler syndrome: Chronic urticaria and monoclonal gammopathy - an autoinflammatory syndrome?

Schnitzler's Syndrome-Diagnostic Experience, Approaches to Therapy, and Patient Management according to a Multicenter Russian Cohort

The objectives of the study were to present the experience of diagnosis, management, and therapy with IL-1 inhibitors in patients with Schnitzler's syndrome (SchS) according to a multicenter Russian cohort. An observational retrospective study for a 10-year period (2012-2022) involved 17 patients with SchS who were admitted to the hospital or were observed on an outpatient basis (eight women and nine men). The diagnosis of all of them corresponded to the Strasbourg diagnostic criteria. The age of patients ranged from 25 to 81 years (Me 53[46; 56]). The age at the time of the onset of the disease ranged from 20 to 72 years (Me 46[39; 54]), the duration of the disease before diagnosis ranged from 1 to 35 years (Me 6.5[3; 6]), in three patients it exceeded 10 years, in the rest it ranged from 1 to 8 years. Infectious and lymphoproliferative diseases, monogenic AIDs (CAPS, TRAPS, and HIDS) were excluded from all patients at the prehospital stage. The referral diagnosis for all of them was Still 's disease in adults. Clinical manifestations of the disease in all patients included fatigue, lethargy, fatigue, rash, and fever. In all patients, skin elements were urticular and were accompanied by itching in 6 (37.5%) patients. Bone pain was observed in 12 (70.6%) patients; arthralgias, in 16 (94.1%); arthritis, in 9 (52.9%); myalgia, in 7 (41.2%); and weight loss, in 4 (23.5%). Lymphadenopathy was detected in 6 (35.3%) patients; enlarged liver, in 6 (35.3%); pericarditis, in 4 (23.5%); angioedema, in 6 (35.3); redness and dryness in the eyes, in 3 (17.6%); sore throat, in 2 (11.8%); abdominal pain, in 1 (5.9%), distal polyneuropathy, in 2 (11.8%); paraesthesia, in 1 (5.9%); and chondritis of the auricles, in 1 (5.9%). Monoclonal gammopathy was detected in all patients with a secretion level of 2.9-15.1 g/L: IgMk (n = 10, 64.7%), less often IgMλ (n = 2), IgGk (n = 2), IgGλ (n = 1), and IgAλ (n = 1). Ben-Jones protein was not detected in any of them. All patients had an increased level of ESR and CRP. Before inclusion in the study, 16 patients received GCs (94.1%) with a temporary effect that disappeared with dose reduction or cancellation. Seven patients received cDMARDs, including methotrexate (5), hydroxychloroquine (2), and cyclophosphamide (1). All patients received NSAIDs and antihistamines, as well as biologics, including the anti-B-cell drug rituximab (1), monoclonal ABs to IgE omalizumab (2, 1 without effect and 1 with partial effect), IL-1i canakinumab (n = 10, 58.8%) subcutaneously once every 8 weeks, and anakinra (n = 4, 23.5%) subcutaneously daily. The duration of taking anakinra, which was prescribed in the test mode, ranged from 1 week to 2.5 months with a further switch to canakinumab in 3 patients. The duration of taking canakinumab at the time of analysis ranged from 7 months to 8 years. Against the background of treatment with IL-1i, 10 out of 11 (90.9%) patients received a complete response in terms of the clinical manifestations of the disease and a decrease in the level of ESR and CRP within a few days. In one patient, a partial response to the administration of anakinra was detected; however, after switching to canakinumab, the effect of treatment was finally lost. One patient received IL-6i for 8 months with an incomplete effect and a positive dynamics after switching to anakinra. Thus, anakinra was initially prescribed to four patients and changed to canakinumab in two of them; canakinumab was started as the first drug in seven patients. Treatment with anakinra was continued in two patients; with canakinumab, in nine patients. In one patient, due to the persistent absence of relapses, the interval between canakinumab injections was increased to 5 months without signs of reactivation; however, subsequently, against the background of stress and relapses of the disease, the intervals were reduced to 4 months. A healthy child was born by the same patient on the background of treatment. The tolerability of therapy was satisfactory in all patients, no SAEs were noted. SchS is a rare multifactorial/non-monogenic AID that should be differentiated from a number of rheumatic diseases and other AIDs. The onset in adulthood, the presence of recurrent urticarial rashes in combination with fever and other manifestations of a systemic inflammatory response are indications for examination for monoclonal secretion. The use of short- or long-acting IL-1i is a highly effective and safe option in the treatment of such patients.

A case of Schnitzler's syndrome without monoclonal gammopathy successfully treated with canakinumab

BACKGROUND

Schnitzler's syndrome (SchS) is a rare autoinflammatory syndrome with diagnostic challenge and be characterized by chronic urticaria, a monoclonal gammopath, periodic fever and bone pain. In addition to the monoclonal gammopathy, bone abnormalities are often found at the site of bone pain in patients with SchS. The remarkable efficacy of interleukin-1 (IL-1) inhibition was also demonstrated in this syndrome.

CASE PRESENTATION

We describe a case of refractory chronic urticaria presenting with clinical manifestations consistent with SchS without monoclonal gammopathy. A 43-year-old female patient suffering from recurring of urticaria with periodic fever as well as bone pain for the past 4 years. The patient had leukocytosis and elevated levels of C-reactive protein (CRP) and serum amyloid A (SAA). PET/CT (positron emission tomography/computed tomography) and MRI (magnetic resonance imaging) examination revealed hyper-metabolism areas in both femoral bone marrow. Although bone marrow histology revealed no abnormality, urticarial skin lesions shows neutrophilic infiltrations without evidence of vasculitis. We could not exclude the possibility of SchS. The patient had been treated with antihistamines, steroids, omarizumab, colchicine and cyclosporine A, no therapeutic effect was observed. She was started on canakinumab 150 mg subcutaneous injection with 4 weeks interval. Within 48 h after the first injection, the urticarial rash disappeared, and febrile attack and bone pain had not recurred. Elevated levels of serum CRP and SAA were normalized within a week after the first injection of canakinumab.

CONCLUSIONS

The current case suggests an important role for IL-1 as a mediator in the pathophysiology of SchS-like refractory urticaria with bine pain. It had been presumed that monoclonal gammopathy may not always present in SchS. It is important to avoid delay in diagnosis and initiation of proper treatment in SchS or autoinflammatory conditions resembling SchS.

[Schnitzler syndrome: A review of literature, the authors' observation, and experience with the interleukin-1 inhibitor canakinumab]

The paper reviews the publications dealing with Schnitzler syndrome, a rare autoinflammatory disease, and describes the authors' own clinical observation. It describes the first Russian experience in successfully using the interleukin-1 inhibitor canakinumab to treat this disease.

Radiotherapy for a breast cancer patient with Schnitzler syndrome: Report of acute toxicity and early follow-up

This article provides description about acute toxicity and early follow-up of one patient treated for breast cancer and Schnitzler syndrome. There are no previously reported cases exploring this interaction on medical literature. The expected radiodermitis to occur in the region treated with radiotherapy along with urticarial-like lesions might be challenging in view of the interaction between symptoms and therapeutic measures.

Schnitzler's syndrome: lessons from 281 cases

Schnitzler’s syndrome is an autoinflammatory disorder characterized by the association of a monoclonal IgM (or IgG) gammopathy, a chronic urticarial rash, and signs and symptoms of systemic inflammation, including fever, arthralgias and bone pain. It was first described in 1972. This review summarizes the clinical features, efficacy of therapies, and follow-up data of the 281 cases that have been reported to date. Also, the results of skin histology, bone imaging, laboratory investigations, and studies of the pathogenesis will be discussed, including the pivotal role of interleukin-1 beta in this disorder.

Schnitzler's syndrome: diagnosis, treatment, and follow-up

Schnitzler's syndrome is characterized by recurrent urticarial rash and monoclonal gammopathy, associated with clinical and biological signs of inflammation and a long-term risk of AA amyloidosis and overt lymphoproliferation. An extensive literature review was performed, and the following questions were addressed during an expert meeting: In whom should Schnitzler's syndrome be suspected? How should the diagnosis of Schnitzler's syndrome be established? How should a patient with Schnitzler's syndrome be treated? How should a patient with Schnitzler's syndrome be followed up?. A diagnosis of Schnitzler's syndrome is considered definite in any patient with two obligate criteria: a recurrent urticarial rash and a monoclonal IgM gammopathy, and two of the following minor criteria: recurrent fever, objective signs of abnormal bone remodeling, elevated CRP level or leukocytosis, and a neutrophilic infiltrate on skin biopsy. It is considered probable, if only 1 minor criterion is present. In patients with monoclonal IgG gammopathies, diagnosis is definite if three minor criteria are present and possible if two are present. First-line treatment in patients with significant alteration of quality of life or persistent elevation of markers of inflammation should be anakinra. Follow-up should include clinical evaluation, CBC and CRP every 3 months and MGUS as usually recommended.

Schnitzler syndrome with cold-induced urticaria

BACKGROUND

Schnitzler syndrome encompasses monoclonal gammopathy, urticaria, inflammation, recurrent fever, bone pain and arthralgia, with occasional lymphadenopathy and/or hepatosplenomegaly. It is a rare condition with approximately 100 cases reported in the literature. To our knowledge, this is the first reported case of cold-induced physical urticaria with Schnitzler syndrome.

MAIN OBSERVATIONS

A 43-year-old woman presented to an allergy and immunology clinic with a 7 year history of chronic urticaria, angioedema with anaphylaxis, monoclonal gammopathy and bone pain. Her urticaria was triggered by cooler temperatures and an ice cube test for cold induced urticaria was positive. In spite of aggressive therapies this patient remains symptomatic.

CONCLUSIONS

Schnitzler syndrome is under-recognized, particularly variants of the classical description of Schnitzler syndrome. Other diseases, especially those of hematologic origin, should be ruled out. This condition is largely refractory to conventional therapies, although novel treatments, such as interleukin-1 receptor inhibitor, may show promise.

Urticarial lesions: if not urticaria, what else? The differential diagnosis of urticaria: part II. Systemic diseases

There are a number of systemic disorders that can manifest with urticarial skin lesions, including urticarial vasculitis, connective tissue diseases, hematologic diseases, and autoinflammatory syndromes. All of these conditions may enter into the differential diagnosis of ordinary urticaria. In contrast to urticaria, urticarial syndromes may manifest with skin lesions other than wheals, such as papules, necrosis, vesicles, and hemorrhages. Lesions may have a bilateral and symmetrical distribution; individual lesions have a long duration, and their resolution frequently leaves marks, such as hyperpigmentation or bruising. Moreover, systemic symptoms, such as fever, asthenia, and arthralgia, may be present. The most important differential diagnosis in this group is urticarial vasculitis, which is a small-vessel vasculitis with predominant cutaneous involvement. Systemic involvement in urticarial vasculitis affects multiple organs (mainly joints, the lungs, and the kidneys) and is more frequent and more severe in patients with hypocomplementemia. Clinicopathologic correlation is essential to establishing a correct diagnosis.

LEARNING OBJECTIVES

After completing the learning activity, participants should be able to distinguish urticarial lesions suggesting diagnoses other than common urticaria; assess patients with urticarial lesions, and suspect systemic diseases presenting with urticarial skin lesions.

Schnitzler syndrome: response to anakinra in two cases and a review of the literature

BACKGROUND

Schnitzler syndrome is a rare disease characterized by a chronic urticarial eruption and monoclonal gammopathy, as well as clinical and laboratory signs of inflammation. The pathophysiology is still unknown, although various autoantibody-mediated mechanisms have been described. Complete remission of symptoms has been reported recently in patients with Schnitzler syndrome treated with anakinra, an interleukin-1 receptor antagonist.

METHODS

Two patients with Schnitzler syndrome treated with anakinra therapy are presented.

RESULTS

We report two cases of nearly complete remission of symptoms in Schnitzler syndrome after the initiation of anakinra therapy, and the first observation of a relapse under continuous daily anakinra therapy. A review of the published literature on the treatment of Schnitzler syndrome with anakinra is presented.

CONCLUSIONS

Based on published data, monotherapy with anakinra is currently the most promising treatment for Schnitzler syndrome, because it is able to induce complete remission of symptoms.

[Periodic fever syndrome/autoinflammatory syndrome]

Hereditary periodic fever syndromes (autoinflammatory syndromes) are characterised by relapsing fevers and additional manifestations such as skin rashes, mucosal manifestations, and joint pain. Some of these disorders only present with organ manifestations and serological signs of inflammation without obvious fever (e.g. PAPA and Blau syndrome). There is a strong serological inflammatory response with an elevation of serum amyloid A (risk of secondary amyloidosis). There are monogenic disorders for which the mode of inheritance and gene mutation are known, but probably also polygenic diseases which present with similar symptoms to the classic autoinflammatory syndromes. Gene mutations have been described for the monogenic disorders (FMF, HIDS, CAPS, PAPA and Blau syndrome), which lead to an induction of the production of IL-1ss. Therapeutically, the IL-1-receptor antagonist anakinra is mainly used. In the case of TRAPS and Blau syndrome, TNF antagonists may also be used. PFAPA syndrome, the Schnitzler syndrome, Still's disease of adult and pediatric onset, Behçet's disaese and Crohn's disease also are mentioned as additional possible autoinflammatory syndromes.

Schnitzler's syndrome: increased levels of bone formation and angiogenesis factors are reduced after successful pefloxacin treatment

Schnitzler's syndrome is characterized by chronic urticaria and monoclonal immunoglobulin (Ig) M gammopathy, with other features including intermittent fever, joint and/or bone pain with radiologic evidence of osteosclerosis, lymphadenopathy, enlarged liver and/or spleen, leukocytosis, and elevated erythrocyte sedimentation rate. The etiology of the syndrome remains obscure, although involvement of various cytokines has been proposed. Bone metabolism and angiogenesis markers are deregulated in Waldenström macroglobulinemia and IgM monoclonal gammopathy of unknown significance, but these markers have not been assessed in Schnitzler's syndrome. Herein, we report a patient with Schnitzler's syndrome who was treated with oral pefloxacin. Serum levels of osteoclast regulators, markers of bone remodeling and angiogenesis cytokines, were measured before treatment and serially after the initiation of treatment. High bone turnover and strikingly elevated levels of angiogenic cytokines were observed at diagnosis. Treatment with pefloxacin resulted in a normalization of the bone remodeling process and a significant reduction of angiogenic cytokines, with rapid and sustained improvement of symptoms, suggesting that these factors might be implicated in the pathophysiology of this syndrome. Furthermore, pefloxacin was proven to be an effective treatment for patients with Schnitzler's syndrome.