%0 Journal Article %T Can HLA-DRB4 Help to Identify Asthmatic Patients at Risk of Churg-Strauss Syndrome? %A P. Bottero %A F. Motta %A M. Bonini %A F. Vecchio %A F. Ierna %A I. Cuppari %A R. A. Sinico %J ISRN Rheumatology %D 2014 %R 10.1155/2014/843804 %X HLA-DRB4 gene is associated with Churg-Strauss syndrome (CSS), a systemic eosinophilic vasculitis with a prodromal phase characterized by severe asthma, eosinophilia, nasal polyposis, and sinusitis. Aim of this study was to evaluate if the presence of HLA-DRB4 in asthmatic patients is associated with a clinical picture resembling that of the prodromal phase of CSS. HLA-DRB1 was determined in a cohort of 159 asthmatic patients and its frequency was compared with that of 1808 blood donors. HLA-DRB4 presence/absence was correlated with clinical features, including sinusitis, nasal polyposis, eosinophils, antiasthmatic drugs, asthma severity, and pulmonary function tests. HLA-DRB4 gene was associated with severe persistent asthma before treatment ( ), near fatal or severe hypoxemic asthma ( ), sinusitis ( ), nasal polyposis ( ), number of patients with eosinophils >1000/¦Ìl: ( ), need of beclomethasone >1000¨C2000£¿¦Ìg/daily ( ), use of a third controller ( ), and oral prednisone ( ). HLA-DRB4 gene is associated in asthmatic patients with a clinical picture characterized by asthma severity, sinusitis, nasal polyposis, and eosinophilia closely resembling that of the prodromal phase of CSS and might be useful to suspect corticosteroids-masked cases of CSS. 1. Introduction Chug-Strauss syndrome (CSS) is a rare form of eosinophilic necrotising antineutrophil cytoplasmic antibodies (ANCA) associated with vasculitis affecting small to medium sized vessels [1]. In most patients, it is characterized by a prodromal phase, in which severe adult onset asthma is the main feature with rhinosinusitis and nasal polyposis, a second phase, with peripheral blood and tissue eosinophilia, and, finally, the systemic vasculitic phase [1]. In accordance with the American College of Rheumatology (ACR) 1990, asthma, eosinophilia >10%, mononeuropathy or polyneuropathy, pulmonary infiltrates nonfixed, paranasal sinuses abnormality, and biopsy with extravascular eosinophils are the major classification criteria of the syndrome. The etiology of CSS is not known. However, its pathogenesis is considered multifactorial: the disease can be triggered by exposure to allergens or drugs; Th2 responses are prominent, with upregulation of several cytokines such as IL-4, IL-13, and IL-5; however, Th1 and Th17 responses are not negligible. In particular, Th17 lymphocytes have been involved in the pathogenesis of both autoimmune diseases and allergy/asthma [2] and, interestingly enough, CCS shares features of allergy/asthma and autoimmunity. A significant prevalence of HLA-DRB4 gene encoding the %U http://www.hindawi.com/journals/isrn.rheumatology/2014/843804/