Schnitzler syndrome

Schnitzler Syndrome

Schnitzler syndrome is a rare, chronic condition characterized by a combination of symptoms including chronic urticaria (hives), periodic fever, bone pain, and monoclonal gammopathy. It was first described by Dr. Liliane Schnitzler in 1972. The exact cause of Schnitzler syndrome is unknown, but it is considered an autoinflammatory disorder.

Clinical Features

The main clinical features of Schnitzler syndrome include:

• Chronic Urticaria: Patients experience recurrent episodes of hives, which are often itchy and can be accompanied by a burning sensation.
• Fever: Periodic fevers are common, often occurring alongside the episodes of urticaria.
• Bone Pain: Many patients report bone pain, particularly in the limbs and pelvis.
• Monoclonal Gammopathy: This is a laboratory finding where there is an abnormal protein in the blood, typically an IgM monoclonal protein.

Other symptoms may include fatigue, weight loss, and enlarged lymph nodes.

Diagnosis

Diagnosing Schnitzler syndrome can be challenging due to its rarity and the overlap of symptoms with other conditions. The diagnosis is primarily clinical, based on the presence of the characteristic symptoms and laboratory findings. The Strasbourg criteria are often used to aid in diagnosis, which include:

• Chronic urticaria
• Recurrent fever
• Bone pain
• Monoclonal IgM or IgG gammopathy
• Neutrophilic dermal infiltrate on skin biopsy

Pathophysiology

The pathophysiology of Schnitzler syndrome is not fully understood. It is classified as an autoinflammatory syndrome, suggesting an innate immune system dysregulation. The role of interleukin-1 (IL-1) in the inflammatory process is significant, as evidenced by the effectiveness of IL-1 inhibitors in treatment.

Treatment

Treatment of Schnitzler syndrome focuses on managing symptoms and reducing inflammation. The most effective treatment is the use of IL-1 inhibitors, such as anakinra, canakinumab, or rilonacept. These medications can significantly reduce symptoms and improve quality of life.

Other treatments may include nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and antihistamines, although these are generally less effective.

Prognosis

The prognosis for Schnitzler syndrome varies. While it is a chronic condition, effective treatment with IL-1 inhibitors can lead to significant symptom relief. However, long-term monitoring is necessary due to the potential risk of progression to lymphoproliferative disorders.

See Also

• Autoinflammatory syndromes
• Monoclonal gammopathy
• Interleukin-1 inhibitors

References

• de Koning, H. D. (2018). Schnitzler's syndrome: Lessons from 281 cases. Clinical and Translational Allergy, 8(1), 1-10.
• Lipsker, D. (2014). The Schnitzler syndrome. Orphanet Journal of Rare Diseases, 9(1), 1-8.

External Links

• [Orphanet: Schnitzler syndrome](https://www.orpha.net/consor/cgi-bin/OC_Exp.php?Lng=EN&Expert=331)
• [NIH Genetic and Rare Diseases Information Center: Schnitzler syndrome](https://rarediseases.info.nih.gov/diseases/10754/schnitzler-syndrome)

NIH genetic and rare disease info

• NIH info on Schnitzler syndrome

Schnitzler syndrome is a rare disease.