The symptoms associated with Schnitzler syndrome can vary from one person to another. The symptoms can occur all at once or, because they often come and go, the symptoms can occur at different times. The symptoms tend to persist for many years (chronic disease).
A reddish, rash that resembles hives (urticaria) is the hallmark finding associated with Schnitzler syndrome. The distinctive rash usually consists of raised, reddish bumps (papules) and flatter, wider lesions (plaques). In most cases, a rash is the first symptom to appear in individuals with Schnitzler syndrome. The rash usually lasts for a day to two and then disappears without scarring. However, a new rash often develops each day so that a rash is a constant occurrence. However, the frequency of the rash can vary greatly from one person to another and some people only develop a rash a few times during the year.
When the rash first develops, it usually is not itchy (pruritic). However, in approximately 45 percent of cases, the rash will become itchy within a few years. The trunk, arms and legs are most often affected. The head, neck, palms and soles are usually spared. Some affected individuals have reported that alcohol, spicy foods and stress have aggravated the rash.
Fevers that come and go over a period of time (chronic, intermittent fevers) are the second most common symptom in individuals with Schnitzler syndrome. The frequency of fevers varies greatly, ranging from being a daily occurrence to only a couple times per year. Fevers are usually unrelated to the skin rash, are well-tolerated and are rarely accompanied by chills.
Additional symptoms associated with Schnitzler syndrome include bone pain, most often affecting the lower legs and hips, and joint pain, most often affecting the large joints such as the hips, knees, wrists and ankles. In some cases, inflammation of the joints (arthritis) may develop with accompanying swelling, redness and a feeling of heat or warmth in the joint. Despite joint involvement, joint degeneration or destruction has not been reported in individuals with Schnitzler syndrome.
Abnormal enlargement of the lymph nodes (lymphadenopathy), the liver (hepatomegaly) and the spleen (splenomegaly) may also occur in some cases. Additional nonspecific symptoms that have been reported in individuals with Schnitzler syndrome include unintended weight loss, fatigue and a general feeling of poor health (malaise). Rapid swelling due to fluid accumulation just beneath the surface skin (angioedema) may complicate the development of a rash in rare cases.
Most cases of Schnitzler syndrome have a chronic, benign course. However, over a period of 10 years, approximately 15 percent of affected individuals developed cancer, most often cancer caused by the overproduction of white blood cells (lymphoproliferative disorders) such as Waldenström macroglobulinemia.
Some individuals with Schnitzler syndrome have elevated levels of a different protein (see Causes section below) than individuals with classic Schnitzler syndrome. These individuals are classified as having variant Schnitzler syndrome and have very similar symptoms to classic Schnitzler syndrome.
The exact cause of Schnitzler syndrome is unknown. Researchers believe that specific parts of the immune system may not function properly eventually causes Schnitzler syndrome.
Individuals with Schnitzler syndrome also have a unique clinical finding called monoclonal IgM gammopathy, in which abnormalities affecting the production of immunoglobulins result in elevated levels of immunoglobulin M (IgM) in the body. Immunoglobulins are proteins produced by certain white blood cells. There are five classes of immunoglobulins known as IgA, IgD, IgE, IgG, and IgM. Immunoglobulins play a role in defending the body against foreign substances or microorganisms by destroying them or coating them so they are more easily destroyed by white blood cells.
Some researchers believe that IgM antibodies accumulate in the skin (epidermis), triggering an inflammatory response that, in turn, causes the characteristic rash associated with Schnitzler syndrome. At the time of diagnosis, IgM levels may only be slightly elevated and may remain stable for years.
A variant form of Schnitzler syndrome has been reported in which individuals have normal IgM levels, but elevated immunoglobulin G (IgG) levels.
Researchers also believe that cytokines (specialized proteins secreted from certain immune system cells that either stimulate or inhibit the function of other immune system cells) may also play a role in the development of Schnitzler syndrome. Interleukin-1 (IL-1) a cytokine that is known to mediate cell response to inflammation is believed to play an important role the development of Schnitzler syndrome. Abnormal clinical findings involving interleukin-1 have been found in some individuals with Schnitzler syndrome and therapy with drugs that block the activity of interleukin-1 have brought about complete remission (see Investigational Therapies below).
Schnitzler syndrome affects males slightly more often than females. However, only approximately 160 cases of this rare disorder have been reported in the medical literature so no definitive conclusions can be made about ethnic or gender predispositions. Because of the varied symptoms and rarity of Schnitzler syndrome, a diagnosis is usually delayed by several years and researchers believe that the disorder is underdiagnosed, making it difficult to determine its true frequency in the general population. Most individuals with Schnitzler syndrome are in their 50s when the characteristic symptoms develop.
Less often, symptoms have been noted in individuals in their 30s. In one reported case, symptoms were identified in an individual 12 years old.
Schnitzler syndrome was first described in the medical literature in 1972, by a French dermatologist named Liliane Schnitzler. Most of the reported cases of Schnitzler syndrome have been from Europe, particularly France, but cases from Australia, Japan and the United States have been reported too.
A diagnosis of Schnitzler syndrome is based upon a thorough clinical evaluation, a detailed patient history, exclusion of other disorders, and identification of characteristic findings, specifically a urticarial rash, an IgM component and at least two of the following findings – fever, joint pain or inflammation, bone pain, palpable lymph nodes, enlargement of the liver or spleen, elevated numbers of white blood cells (leukocytosis), elevated red blood cell (erythrocyte) sedimentation rate or abnormalities on bone morphological study, which can reveal increased bone density (osteosclerosis).
Sedimentation rate measures how long it takes red blood cells to settle in a test tube over a given period. Many individuals with Schnitzler syndrome have an elevated sedimentation rate, which is an indication of inflammation.
In younger patients, careful attention should be paid because alternative diagnosis is much more likely and often overlooked – such as urticarial vasculitis or chronic idiopathic urticaria – which needs a different approach to treatment – so a diagnosis of Schnitzler’s syndrome in younger patients should only be made after extensive work on exclusion of other diagnoses.
First-line treatment in mild cases is with nonsteroidal anti-inflammatory drugs (NSAIDs). But this is often not sufficient.
In more severe cases, the standard treatment is with therapy to inhibit the cytokine IL-1. Patients with Schnitzler syndrome are successfully treated with anakinra, an interleukin-1 receptor antagonist. Anakinra is a drug that blocks the activity of interleukin-1, which some researchers believe plays a key role in the development of Schnitzler syndrome. There has also been a study showing the efficacy of the interleukin-1 beta antibody canakinumab.
High-dose regimens of corticosteroids have temporarily improved symptoms in some cases, but usually must be stopped due to side effects. In a small percentage of cases, colchicine (a medication used to suppress inflammation in acute gout) and dapsone have proven effective in treating some individuals with Schnitzler syndrome. Interleukin-6 is a cytokine that can be induced by interleukin-1 and therefore, anti-interleukin-6 therapy was also recently tried in three patients with Schnitzler syndrome, in which it was effective.
At least three individuals with Schnitzler syndrome have been successfully treated with thalidomide, a drug that affects how the immune system works (immunomodulatory drugs). Thalidomide induced a complete resolution of the rash and dramatic improvement of other symptoms in three individuals who received the drug as a therapy for Schnitzler syndrome. However, thalidomide is often associated with significant side effects including pain, numbness and a tingling sensation in the hands and feet (peripheral neuropathy). Two of the three patients had to stop thalidomide therapy because of side effects. In addition, two additional individuals with Schnitzler syndrome did not improve after treatment with thalidomide. More research is necessary to determine the long-term safety, effectiveness and role, if any, of thalidomide in treating individuals with Schnitzler syndrome.
A small study investigated the effectiveness of the antibiotic drug, pefloxacine, for the treatment of Schnitzler syndrome. Eleven affected individuals received pefloxacine, which caused rapid and dramatic improvement of both the rash and systemic symptoms associated with the disorder. More research is necessary to determine the long-term safety and effectiveness of pefloxacine in the treatment of individuals with Schnitzler syndrome.
Schnitzler syndrome does not affect lifespan in most cases, but requires periodic follow up because of the increased risk of developing cancer.
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Toll-free: (800) 411-1222
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For information about clinical trials sponsored by private sources, contact:
For information about clinical trials conducted in Europe, contact:
Researchers in the department of General Internal Medicine at the Radboud University Medical Center Nijmegen, The Netherlands, have created a website to provide information and support for individuals with Schnitzler syndrome. The researchers have an active interest in this rare disorder and have started an international registry on Schnitzler syndrome. The registry is a database that catalogues information on affected individuals to increase knowledge of this disorder. The Web site is located at: http://www.autoinflammatie.nl/ENG/folder9/index.php
Krause K, Feist E, Fiene M, Kallinich T, Maurer M. Complete remission in 3 of 3 anti-IL-6 treated patients with Schnitzler syndrome. J.Allergy Clin.Immunol. J Allergy Clin Immunol. 2012;129(3):848-50.
de Koning HD, Schalkwijk J, van der Meer JW, Simon A. Successful canakinumab treatment identifies IL-1beta as a pivotal mediator in Schnitzler syndrome. J.Allergy Clin.Immunol. 2011;128(6):1352-4.
Dybowski F, Sepp N, Bergerhausen HJ, Braun J. Successful use of anakinra to treat refractory Schnitzler’s syndrome. Clin Exp Rheumatol. 2008;26:354-357.
Asli B, Bienvenu B, Cordoliani F, et al. Chronic urticaria and monoclonal IgM gammopathy (Schnitzler syndrome). Report of 11 cases treated with pefloxacin. Arch Dermatol. 2007;143:1046-1050.
de Koning HD, Bodar EJ, van der Meer JW, Simon A. Schnitzler syndrome: beyond the case reports: review and follow-up of 94 patients with an emphasis on prognosis and treatment. Semin Arthritis Rheum. 2007;37:137-148.
de Koning HD, Bodar EJ, Simon A, van der Hilst JC, Netea MG, van der Meer JW. Beneficial response to anakinra and thalidomide in Schnitzler’s syndrome. Ann Rheum Dis. 2006;65:542-544.
Worm M, Kolde G. Schnitzler’s syndrome: successfully treatment of two patients using thalidomide. Br J Dermatol. 2003;148:601-602.
Shibolet O, Schatz O, Krieger M, Maly A, Caraco Y. Schnitzler syndrome: chronic urticaria, fever and immunoglobulin M monoclonal gammopathy. IMAJ. 2002;4:466-467.
Lipsker D, Veran Y, Grunenberger F, Cribier B, Heid E, Grosshans E. The Schnitzler syndrome. Four cases and review of the literature. Medicine (Baltimore). 2001;80:37-44.
DeKoven JG, Pon K. Schnitzler Syndrome.Medscape. http://emedicine.medscape.com/article/1050761-overview Updated: Apr 28, 2014. Accessed May 19, 2015.
Lipsker D. Schnitzler Syndrome. Orphanet encyclopedia, http://www.ojrd.com/content/5/1/38/abstract . Published: 8 December 2010. Accessed May 19, 2015.