A case of mixed dust pneumoconiosis with desquamative interstitial pneumonia-like reaction in an aluminum welder

A 60-year-old man presented with an 18-month history of gradually worsening cough and a 12-month history of dyspnea on exertion. High-resolution computed tomography showed bilateral uniform ground grass opacity in the lower lung fields, partially resolved by smoking cessation. A tentative diagnosis of desquamative interstitial pneumonia (DIP) was made. Video-assisted thoracic surgery was performed and pathological analysis showed peribronchiolar fibrosis with intra-alveolar macrophage infiltration. Elemental analysis detected aluminum and iron in the upper lobe and only iron in the lower lobe. Thus, a definitive diagnosis of mixed dust pneumoconiosis with DIP-like reaction was made. DIP-like reaction is known to be a reactive change caused by exposure to tobacco smoke as well as by inhalation of inorganic particles. Obtaining a detailed medical history including occupational and environmental risk factors is important to distinguish cases of DIP-like reaction due to exposure to inorganic particles from the usual cases related to smoking, and thus provide suitable treatment

Clinical Significance of Interleukin 33 (IL-33) in Patients with Eosinophilic Pneumonia

ABSTRACTBackground: Interleukin 33 (IL-33) works as a functional mediator in allergic disease by enhancing the activity of eosinophils and inducing expression of T helper 2 (Th2)-associated cytokines. However, the role of IL-33 in pulmonary eosinophilia has not been elucidated. We investigated the levels of IL-33 in eosinophilic pneumonia (EP) together with associated cytokines, and discussed the clinical significance of IL-33 in EP.Methods: Sera and bronchoalveolar lavage fluid (BALF) were obtained from 16 patients with EP, including acute eosinophilic pneumonia (AEP) and chronic eosinophilic pneumonia (CEP). Twelve patients with acute respiratory distress syndrome (ARDS) were also included for comparison. The concentration of IL-33 and Th2 cytokines (IL-4, IL-5, IL-13) were measured by enzyme-linked immunosorbent assay (ELISA).Results: The concentration of serum IL-33 was significantly higher in patients with AEP than in CEP. In CEP, only patients with atopic factors showed mild increase of serum IL-33. The concentration of BALF IL-33 was also significantly elevated in AEP, however, it remained quite low in CEP. Among Th2 cytokines, IL-5 was significantly increased in both serum and BALF in AEP, and the level of IL-5 was positively correlated with that of IL-33. ARDS showed no increase of serum and BALF IL-33.Conclusions: The remarkable increase of BALF IL-33 in AEP indicated the local production of IL-33 in lungs. IL-33 is considered to be a local key molecule for triggering pulmonary eosinophilia, together with IL-5. BALF IL-33 appears to be a useful marker for discriminating AEP from CEP and ARDS