Severe chronic allergic (and related) diseases: a uniform approach--a MeDALL--GA2LEN--ARIA position paper.
WHO Collaborating Center for Asthma and Rhinitis None., Bousquet J., Anto JM., Demoly P., Schünemann HJ., Togias A., Akdis M., Auffray C., Bachert C., Bieber T., Bousquet PJ., Carlsen KH., Casale TB., Cruz AA., Keil T., Lodrup Carlsen KC., Maurer M., Ohta K., Papadopoulos NG., Roman Rodriguez M., Samolinski B., Agache I., Andrianarisoa A., Ang CS., Annesi-Maesano I., Ballester F., Baena-Cagnani CE., Basagaña X., Bateman ED., Bel EH., Bedbrook A., Beghé B., Beji M., Ben Kheder A., Benet M., Bennoor KS., Bergmann KC., Berrissoul F., Bindslev Jensen C., Bleecker ER., Bonini S., Boner AL., Boulet LP., Brightling CE., Brozek JL., Bush A., Busse WW., Camargos PAM., Canonica GW., Carr W., Cesario A., Chen YZ., Chiriac AM., Costa DJ., Cox L., Custovic A., Dahl R., Darsow U., Didi T., Dolen WK., Douagui H., Dubakiene R., El-Meziane A., Fonseca JA., Fokkens WJ., Fthenou E., Gamkrelidze A., Garcia-Aymerich J., Gerth van Wijk R., Gimeno-Santos E., Guerra S., Haahtela T., Haddad H., Hellings PW., Hellquist-Dahl B., Hohmann C., Howarth P., Hourihane JO., Humbert M., Jacquemin B., Just J., Kalayci O., Kaliner MA., Kauffmann F., Kerkhof M., Khayat G., Koffi N'Goran B., Kogevinas M., Koppelman GH., Kowalski ML., Kull I., Kuna P., Larenas D., Lavi I., Le LT., Lieberman P., Lipworth B., Mahboub B., Makela MJ., Martin F., Martinez FD., Marshall GD., Mazon A., Melen E., Meltzer EO., Mihaltan F., Mohammad Y., Mohammadi A., Momas I., Morais-Almeida M., Mullol J., Muraro A., Naclerio R., Nafti S., Namazova-Baranova L., Nawijn MC., Nyembue TD., Oddie S., O'Hehir RE., Okamoto Y., Orru MP., Ozdemir C., Ouedraogo GS., Palkonen S., Panzner P., Passalacqua G., Pawankar R., Pigearias B., Pin I., Pinart M., Pison C., Popov TA., Porta D., Postma DS., Price D., Rabe KF., Ratomaharo J., Reitamo S., Rezagui D., Ring J., Roberts R., Roca J., Rogala B., Romano A., Rosado-Pinto J., Ryan D., Sanchez-Borges M., Scadding GK., Sheikh A., Simons FER., Siroux V., Schmid-Grendelmeier PD., Smit HA., Sooronbaev T., Stein RT., Sterk PJ., Sunyer J., Terreehorst I., Toskala E., Tremblay Y., Valenta R., Valeyre D., Vandenplas O., van Weel C., Vassilaki M., Varraso R., Viegi G., Wang DY., Wickman M., Williams D., Wöhrl S., Wright J., Yorgancioglu A., Yusuf OM., Zar HJ., Zernotti ME., Zidarn M., Zhong N., Zuberbier T.
Concepts of disease severity, activity, control and responsiveness to treatment are linked but different. Severity refers to the loss of function of the organs induced by the disease process or to the occurrence of severe acute exacerbations. Severity may vary over time and needs regular follow-up. Control is the degree to which therapy goals are currently met. These concepts have evolved over time for asthma in guidelines, task forces or consensus meetings. The aim of this paper is to generalize the approach of the uniform definition of severe asthma presented to WHO for chronic allergic and associated diseases (rhinitis, chronic rhinosinusitis, chronic urticaria and atopic dermatitis) in order to have a uniform definition of severity, control and risk, usable in most situations. It is based on the appropriate diagnosis, availability and accessibility of treatments, treatment responsiveness and associated factors such as comorbidities and risk factors. This uniform definition will allow a better definition of the phenotypes of severe allergic (and related) diseases for clinical practice, research (including epidemiology), public health purposes, education and the discovery of novel therapies.