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Schnitzler Syndrome

The information in NORD’s Rare Disease Database is for educational purposes only. It should never be used for diagnostic or treatment purposes. If you have questions regarding a medical condition, always seek the advice of your physician or other qualified health professional. NORD’s reports provide a brief overview of rare diseases. For more specific information, we encourage you to contact your personal physician or the agencies listed as “Resources” on this report.

Copyright 2008, 2012

NORD is very grateful to A. Simon, MD, PhD and H. de Koning, MD, Radboud University Nijmegen Medical Centre, Department of General Internal Medicine, The Netherlands and the N4i Centre for Immunodeficiency and Autoinflammation, for assistance in the preparation of this report.

Synonyms of Schnitzler Syndrome

Disorder Subdivisions

General Discussion

Schnitzler syndrome is a rare disorder characterized by a chronic reddish rash that resembles hives (urticaria) and elevated levels of a specific protein in the blood (monoclonal IgM gammopathy). Symptoms associated with Schnitzler syndrome may include repeated bouts of fever, joint inflammation (arthritis), joint pain (arthralgia), bone pain, and other findings such as enlarged lymph nodes (lymphadenopathy). A monoclonal IgM gammopathy refers to the uncontrolled growth of a single clone (monoclonal) of plasma cells, which results in the abnormal accumulation of M-proteins (also known as immunoglobulin M or IgM) in the blood. These proteins are supposed to fight foreign substances in the body such as viruses and bacteria, but researchers suspect that they play a role in the development of Schnitzler syndrome. However, the specific role these proteins play and the exact cause of Schnitzler syndrome is unknown. Schnitzler syndrome is difficult to classify and some researchers have suggested that it is an acquired autoinflammatory syndrome. Autoinflammatory syndromes are a group of disorders characterized by recurrent episodes of inflammation due to an abnormality of the innate immune system. They are not the same as autoimmune disorders, in which the adaptive immune system malfunctions and mistakenly attacks healthy tissue.

Symptoms

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.

Causes

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).

Affected Populations

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.

Related Disorders

Symptoms of the following disorders can be similar to those of Schnitzler syndrome. Comparisons may be useful for a differential diagnosis.

Autoinflammatory syndromes are a group of disorder characterized by recurrent episodes of inflammation due to an abnormality of the innate immune system. Symptoms of the syndromes often include periodic fevers, rash, abdominal pain, joint pain, bone pain and other characteristic findings associated with chronic inflammation. These disorders include the cryoprin-associated periodic syndromes (familial cold autoinflammatory syndrome, CINCA, and Muckle-Wells syndrome), hyperimmunoglobulin D syndrome (HIDS), familial Mediterranean fever (FMF), TRAPS, and mevalonate kinase deficiency. (For more information on this disorder, choose the specific disorder name as your search term in the Rare Disease Database.)

Autoimmune disorders are a group of disorders in which the abnormalities affecting the adaptive immune system, which consists of cells and proteins (antibodies) that are suppose to protect the body from infection. These antibodies mistakenly attack healthy tissue and may be referred to as autoantibodies. Symptoms common to many autoimmune disorders include repeated episodes of fever, rash, abdominal pain, joint pain and other symptoms associated with chronic inflammation. Autoimmune disorders that may resemble Schnitzler syndrome include acquired C1 inhibitor deficiency, adult-onset Still's disease, systemic lupus erythematosus, (For more information on this disorder, choose the specific disorder name as your search term in the Rare Disease Database.)

POEMS syndrome is an extremely rare multisystem disorder. POEMS is an acronym that stands for (P)olyneuropathy, disease affecting many nerves; (O)rganomegaly, abnormal enlargement of an organ; (E)ndocrinoapthy, disease affecting certain hormone-producing glands that help to regulate the rate of growth, sexual development, and certain metabolic functions (endocrine system); (M)onoclonal gammopathy or M proteins; and (S)kin defects. Common symptoms include progressive weakness of the nerves in the arms and legs, an abnormally enlarged liver and/or spleen (hepatosplenomegaly), abnormally darkening of the skin (hyperpigmentation) and excessive hair growth (hypertrichosis). Endocrine abnormalities such as failure of the ovaries and testes (gonads) to function properly (primary gonadal failure) and diabetes mellitus type I may be present. Specific endocrine abnormalities associated with POEMS syndrome vary from case to case. Other important features of the disease include swelling around the optic nerve (papilledema), abnormal fluid retention, which may occur in the ankles (edema), the abdominal cavity (ascites), or around the lungs (pleural effusions), painless scars on bone x-ray (osteosclerosis), and an elevated platelet count (a blood cell responsible for clotting). POEMS syndrome is associated with a group of disorders known as monoclonal gammopathies or plasma cell dyscrasias. These disorders are characterized the uncontrolled growth of a single clone (monoclonal) of plasma cells, which results in the abnormal accumulation of M-proteins (IgM) in the blood. (For more information on this disorder, choose "POEMS" as your search term in the Rare Disease Database.)

Waldenström macroglobulinemia (WMG) is a slow-growing (indolent) malignant (cancerous) disorder of the blood, closely related to lymphoma and characterized by the presence of abnormally large numbers of a particular kind of white blood cell known as B lymphocytes. As these cells accumulate in the body, excessive quantities of an antibody known as a monoclonal immunoglobulin M (IgM) are produced. This causes the blood to become thick (hyperviscosity) and affects the flow of blood through the smaller blood vessels, leading to some of symptoms of the disorder. Accumulation of B lymphocytes in the bone marrow can inhibit bone marrow production of new blood cells (pancytopenia). Affected individuals may have low levels of red blood cells (anemia), white blood cells (leukopenia) and platelets (thrombocytopenia). Consequently, affected individuals may experience fatigue, pallor, nose bleeds, and susceptibility to infection. Some individuals with Schnitzler syndrome have developed Waldenström macroglobulinemia later in life. The exact relationship between these two disorders is not fully understood. The exact cause of Waldenström macroglobulinemia is not known. (For more information on this disorder, choose "Waldenstrom macroglobulinemia" as your search term in the Rare Disease Database.)

Standard Therapies

Diagnosis
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.

Treatment
Many different therapies have been tried for individuals with Schnitzler syndrome. No one treatment has proven consistently effective in all cases. Nonsteroidal anti-inflammatory drugs (NSAIDs) are often tried first because fever, joint pain and bone pain have responded to treatment with these drugs. Corticosteroid drugs and drugs that suppress the immune system (immunosuppressives) may provide some relief from bone and joint pain as well.

These therapies rarely result in sustained improvement of the characteristic skin rash associated with Schnitzler syndrome, which has proven particularly resistant to treatment. 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.

In recent years, some promising therapies including Anakinra, thalidomide, and pefloxacine have been used as treatment for individuals with Schnitzler syndrome (see Investigational Therapies below).

Schnitzler syndrome does not affect lifespan in most cases, but requires periodic follow up because of the increased risk of developing cancer.

Investigational Therapies

Several individuals with Schnitzler syndrome have been 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. Although anakinra has only been used in a handful of individuals with Schnitzler syndrome, those who have received the therapy have achieved complete remission. However, more research is necessary to determine the long-term safety and effectiveness of this promising therapy for individuals with Schnitzler syndrome. The success of anakinra in treating individuals with Schnitzler syndrome suggests that interleukin-1 does indeed play a major role in the development of the disorder.

In three patients to date, the interleukin-1 beta antibody canakinumab was found to be highly effective too. Long-term efficacy and safety data in more patients are required.

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. Also for this treatment (toculizumab), long-term efficacy and safety data in more patients are required.

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.

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
TTY: (866) 411-1010
Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:
www.centerwatch.com

Researchers in the department of General Internal Medicine at the Radboud University Medical Center Nijmegen, The Netherlands, have created a Web site 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: www.schnitzlersyndrome.com/index.htm

Schnitzler Syndrome Resources

Organizations:

References

JOURNAL ARTICLES
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.

INTERNET
DeKoven JG, Pon K. Schnitzler Syndrome. Emedicine. http://emedicine.medscape.com/article/1050761-overview. Updated January 11, 2012. Accessed March 13, 2012.

Lipsker D. Schnitzler Syndrome. Orphanet encyclopedia,. http://www.orpha.net/data/patho/GB/uk-schnitzler.pdf. Updated May 2004. Accessed March 13, 2012.

Report last updated: 2012/03/16 00:00:00 GMT+0