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Get to Know the Label: CSU

The scientific community has made great strides in the learning origins of chronic spontaneous urticaria. Find out more, here.

Admin Page Luke

Luke is a Skin to Live In writer living with Urticaria for over ten years. He’s active in the urticaria community online and has many powerful stories to tell. He is also married and currently lives in Canada with his wife and newborn.

Not many people like labels – unless they’re designer ones and they’re on sale. But sometimes labels can be helpful. Take the chronic spontaneous urticaria (CSU) label, for example. Before experts agreed on the term in 2009[i], all we knew was that some people’s urticaria was different than others. But from a medical standpoint, any kind of urticaria was just…well…urticaria: Raised, itchy, wheals on the skin that may have looked like an allergic reaction, coupled with possible sudden swelling.[ii], [iii]

But anyone living with CSU can tell you that the occasional mild outbreak of hives doesn’t really compare to the challenges of CSU. So if the two experiences are so different, why couldn’t anyone land on a label that helped this disease make sense?

Well, that’s because urticaria doesn’t make a whole lot of sense. The triggers of urticaria vary greatly from one person to the next, skin flare-ups last for different lengths of time,[iv] and symptoms can range widely.[v] There is also the fact that around half of people with some form of urticaria don’t respond to standard treatment.[vi] So you can start to see why defining and understanding different types of urticaria has been a long, painful process that often ended with doctors and researchers scratching their heads.

 

Identifying different types of urticaria

In an effort to find more about the frustrating disease, researchers delved deeper into the science behind it. Recognizing that a system for classifying the different forms of urticaria would be helpful, representatives from a number of important bodies, including the dermatology section of the European Academy of Allergy and Clinical Immunology (EAACI), the Global Allergy and Asthma European Network (GA2LEN), the European Dermatology Forum (EDF), and the World Allergy Organization (WAO), all sat down to hash out classification guidelines. These guidelines were first published in The European Journal of Allergy and Clinical Immunology in 2009,[vii] and the definitions and classifications of urticaria were first created.[viii]

 

Understanding CSU

So what is CSU? Other than being incredibly frustrating, there are a few factors that set it apart from other forms of urticaria. First, the symptoms may seem to appear from nowhere and reoccur almost daily for at least six weeks (this is where the chronic part of the label comes from).[ix] Second, the symptoms are not triggered by any identified external factor[x] - that’s the spontaneous bit.

CSU actually accounts for around 90% of the chronic subtypes.[xi] More than half of these appear to be caused by an autoimmune mechanism (researchers haven’t been able to identify what causes the rest of CSU diagnoses),[xii] with the immune system triggering mast cells in the skin to release histamine.[xiii] This in turn causes the cells lining the blood vessels to separate, so that tissue fluid leaks out, forming a wheal. Histamine also affects the sensory nerves, which is what gives rise to that frustrating itch.[xiv]

 

CSU vs. CIU

So what about chronic idiopathic urticaria (CIU)? That’s another label you might have heard doctors using. There’s a lot of conversation online focusing on one or the other, but have no fear, CIU and CSU are actually the same thing.[xv] The word idiopathic comes from the Greek word idios meaning one’s own, and pathic meaning illness. So, it is basically saying, “your own unique illness” – a term doctors use when the origin of a disease isn’t clear.[xvi]

 

The right next steps

Now that doctors are aware of the different sub-types of urticaria, a diagnosis is not only easier, but also more accurate. That means you get to the important stuff sooner - the conversation about managing your symptoms may begin. So what’s the first step for someone who thinks they may have CSU? Let’s start with the basic one – talk to your doctor. They are the experts and are there to give you what you need. Although there are still plenty of questions to be answered about CSU, the days of experts scratching their heads in confusion are over – which may mean you could possibly reduce your scratching, too!

 

 

 

References: 

[i] EAACI/GA(2)LEN/EDF/WAO guideline: definition, classification and diagnosis of urticaria. Zuberbier T1, Asero R, Bindslev-Jensen C, Walter Canonica G, Church MK, Giménez-Arnau A, Grattan CE, Kapp A, Merk HF, Rogala B, Saini S, Sánchez-Borges M, Schmid-Grendelmeier P, Schünemann H, Staubach P, Vena GA, Wedi B, Maurer M; Dermatology Section of the European Academy of Allergology and Clinical Immunology; Global Allergy and Asthma European Network; European Dermatology Forum; World Allergy Organization. Allergy. 2009 Oct;64(10):1417-26.

http://www.ncbi.nlm.nih.gov/pubmed/19772512  / http://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2009.02179.x/epdf

 

[ii] Asthma and Allergy Foundation of America (AAFA) website. "Chronic Urticaria (Hives)." Accessed July 2014. http://www.aafa.org/page/allergies.aspxamp;sub=23&amp;cont=328&

 

[iii] Skin to Live In. Urticaria – A Real Problem. May 2015. http://www.skintolivein.com/urticaria/urticaria-a-real-problem/

 

[iv] Unmet clinical needs in chronic spontaneous urticaria. A GA2LEN task force report. Maurer, M., Weller, K., Bindslev-Jensen, C., Giménez-Arnau, A., Bousquet, P. J., Bousquet, J., Canonica, G. W., Church, M. K., Godse, K. V., Grattan, C. E. H., Greaves, M. W., Hide, M., Kalogeromitros, D., Kaplan, A. P., Saini, S. S., Zhu, X. J. and Zuberbier, T. (2011), Allergy, 66: 317–330. http://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2010.02496.x/full

 

[vi] Unmet clinical needs in chronic spontaneous urticaria. A GA2LEN task force report. Maurer, M., Weller, K., Bindslev-Jensen, C., Giménez-Arnau, A., Bousquet, P. J., Bousquet, J., Canonica, G. W., Church, M. K., Godse, K. V., Grattan, C. E. H., Greaves, M. W., Hide, M., Kalogeromitros, D., Kaplan, A. P., Saini, S. S., Zhu, X. J. and Zuberbier, T. (2011), Allergy, 66: 317–330. http://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2010.02496.x/full

  

[vii]  Unmet clinical needs in chronic spontaneous urticaria. A GA2LEN task force report. Maurer, M., Weller, K., Bindslev-Jensen, C., Giménez-Arnau, A., Bousquet, P. J., Bousquet, J., Canonica, G. W., Church, M. K., Godse, K. V., Grattan, C. E. H., Greaves, M. W., Hide, M., Kalogeromitros, D., Kaplan, A. P., Saini, S. S., Zhu, X. J. and Zuberbier, T. (2011), Allergy, 66: 317–330. http://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2010.02496.x/full

 

[viii] EAACI/GA(2)LEN/EDF/WAO guideline: definition, classification and diagnosis of urticaria. Zuberbier T1, Asero R, Bindslev-Jensen C, Walter Canonica G, Church MK, Giménez-Arnau A, Grattan CE, Kapp A, Merk HF, Rogala B, Saini S, Sánchez-Borges M, Schmid-Grendelmeier P, Schünemann H, Staubach P, Vena GA, Wedi B, Maurer M; Dermatology Section of the European Academy of Allergology and Clinical Immunology; Global Allergy and Asthma European Network; European Dermatology Forum; World Allergy Organization. Allergy. 2009 Oct;64(10):1417-26.

http://www.ncbi.nlm.nih.gov/pubmed/19772512  / http://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2009.02179.x/epdf

 

 [ix] The EAACI/GA2LEN/EDF/WAO Guideline for the definition, classification,

diagnosis, and management of urticaria: the 2013 revision and update. Zuberbier T, Aberer W, Asero R, Bindslev-Jensen C, Brzoza Z, Canonica GW, Church MK, Ensina LF, Gimenez-Arnau A, Godse K, Goncalo M, Grattan C, Hebert J, Hide M, Kaplan A, Kapp A, Abdul Latiff AH, Mathelier-Fusade P, Metz M, Nast A, Saini SS, Sanchez-Borges M, Schmid-Grendelmeier P, Simons FER, Staubach P, Sussman G, Toubi E, Vena GA, Wedi B, Zhu XJ, Maurer M. Allergy 2014.

http://www.ga2len.net/PDF/Guideline.pdf

 

 

[x] Kaplan AP. Treatment of Chronic Spontaneous Urticaria. Allergy, Asthma & Immunology Research. 2012;4(6):326-331. doi:10.4168/aair.2012.4.6.326. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3479225/

 

 

[1] Kaplan AP. Treatment of Chronic Spontaneous Urticaria. Allergy, Asthma & Immunology Research. 2012;4(6):326-331. doi:10.4168/aair.2012.4.6.326. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3479225/  

 

[1] Chronic Urticaria and Autoimmunity. Kathleen Fraser, Lynne Robertson Disclosures. Skin Therapy Letter. 2013;18(7) http://www.medscape.com/viewarticle/815273

 

[1] Chronic Urticaria and Autoimmunity. Kathleen Fraser, Lynne Robertson Disclosures. Skin Therapy Letter. 2013;18(7) http://www.medscape.com/viewarticle/815273

 

[1] An approach to the patient with urticaria. S J Deacock. Clin Exp Immunol. 2008 Aug; 153(2): 151–161. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2492902/

 

[1] Shim W-S, Oh U. Histamine-induced itch and its relationship with pain. Molecular Pain. 2008;4:29. doi:10.1186/1744-8069-4-29. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2519061

 

[1] Unmet clinical needs in chronic spontaneous urticaria. A GA2LEN task force report. Maurer, M., Weller, K., Bindslev-Jensen, C., Giménez-Arnau, A., Bousquet, P. J., Bousquet, J., Canonica, G. W., Church, M. K., Godse, K. V., Grattan, C. E. H., Greaves, M. W., Hide, M., Kalogeromitros, D., Kaplan, A. P., Saini, S. S., Zhu, X. J. and Zuberbier, T. (2011), Allergy, 66: 317–330. http://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2010.02496.x/full

 

 

[1] Website “Oxford Dictionaries” – Idiopathic. Last accessed: 26.09.16. https://en.oxforddictionaries.com/definition/idiopathic

 

 

 

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