TY - JOUR T1 - Seasonal variation of serum KL-6 levels in patients with interstitial lung diseases JF - European Respiratory Journal JO - Eur Respir J VL - 44 IS - Suppl 58 SP - P743 AU - Hiroshi Ohnishi AU - Shintaro Miyamoto AU - Shigeo Kawase AU - Tetsuya Kubota AU - Akihito Yokoyama Y1 - 2014/09/01 UR - http://erj.ersjournals.com/content/44/Suppl_58/P743.abstract N2 - Background: Krebs von den Lungen-6 (KL-6) in sera is a useful biomarker for the diagnosis of interstitial lung diseases (ILD). However, KL-6 cannot be applied to discriminate types of ILD. Some case reports demonstrated that serum KL-6 levels were changed depending on antigen exposure levels in patients with hypersensitivity pneumonitis (HP), however seasonal changes in serum KL-6 levels in ILD are unknown.Aims and objectives: The aim of this study was to determine seasonal variation of serum KL-6 levels in various ILD.Methods: Serum KL-6 levels in the summer (June-September) and the winter (November-February) were retrospectively analyzed in 93 patients with ILD including idiopathic pulmonary fibrosis (IPF, n=16), non-specific interstitial pneumonia (NSIP, n=16), collagen vascular disease-associated interstitial pneumonia (CVD-IP, n=33), house-related HP (House-HP, n=9), bird-related HP (Bird-HP, n=6), and combined pulmonary fibrosis and emphysema (CPFE, n=13).Results: CVD-IP and CPFE showed lower serum KL-6 levels than the other ILD throughout their clinical course regardless of the season. Bird-HP and House-HP showed greater seasonal variation in serum KL-6 levels compared with the other ILD. Serum KL-6 levels in Bird-HP were significantly increased in the winter. House-HP showed significant increases of serum KL-6 in the summer. Variations in serum KL-6 levels were significantly greater in acute form of HP than chronic form of HP.Conclusions: HP should be considered in ILD with greater seasonal changes in serum KL-6 levels. ER -