Byung Woo Jhun1, Se Jin Kim2, Kang Kim3, Ji Eun Lee4, Duck Jin Hong5. 1. Division of Pulmonary and Critical Care Medicine, Department of Medicine, The Armed Forces Capital Hospital, Seong-nam, Gyeonggi Province, Republic of Korea. Electronic address: byungwoo.jhun@gmail.com. 2. Division of Pulmonary and Critical Care Medicine, Department of Medicine, The Armed Forces Capital Hospital, Seong-nam, Gyeonggi Province, Republic of Korea. Electronic address: chrisjinny@naver.com. 3. Division of Pulmonary and Critical Care Medicine, Department of Medicine, The Armed Forces Capital Hospital, Seong-nam, Gyeonggi Province, Republic of Korea. Electronic address: newtypex0317@gmail.com. 4. Division of Pulmonary and Critical Care Medicine, Department of Medicine, The Armed Forces Capital Hospital, Seong-nam, Gyeonggi Province, Republic of Korea. Electronic address: leejieun77@gmail.com. 5. Department of Laboratory Medicine, The Armed Forces Capital Hospital, Seong-nam, Gyeonggi Province, Republic of Korea. Electronic address: dududuck@hanmail.net.
Abstract
BACKGROUND: The peripheral eosinophil count (PEC) tends to increase during the course of acute eosinophilic pneumonia (AEP), and an initially elevated PEC is associated with milder disease. However, there is a lack of data regarding these phenomena and inflammatory process of AEP. METHODS: We prospectively evaluated serial changes in serum interleukin (IL)-5 levels and the correlation between the initial level of IL-5 and the PEC to investigate whether the initial PEC indicates a resolving state of inflammation. We also evaluated serum tryptase levels to investigate the possibility of involvement of mast cell activity in AEP. RESULTS: Twenty-one AEP patients were included, and all patients improved within 10 days after corticosteroid treatment. The median initial serum IL-5 level among all patients was 561.0 pg/mL, which decreased to zero at 10 days of follow-up (n = 15, P < 0.001). The median initial serum tryptase level (detectable in 20 of 21 patients) was 3.7 ng/mL and decreased to a median of 1.1 ng/mL at 10 days of follow-up (n = 15, P < 0.001). The initial serum IL-5 and C-reactive protein levels were positively correlated (P = 0.009, r = 0.556), and the initial serum IL-5 level was inversely correlated with the initial PEC (P = 0.004, r = -0.603). CONCLUSIONS: Our data suggest that IL-5 is an important cytokine involved in the recruitment of eosinophils from peripheral blood into the lungs, that an initially elevated PEC is associated with a resolving state of inflammation, and that mast cells are potentially involved in the inflammatory process of AEP.
BACKGROUND: The peripheral eosinophil count (PEC) tends to increase during the course of acute eosinophilic pneumonia (AEP), and an initially elevated PEC is associated with milder disease. However, there is a lack of data regarding these phenomena and inflammatory process of AEP. METHODS: We prospectively evaluated serial changes in serum interleukin (IL)-5 levels and the correlation between the initial level of IL-5 and the PEC to investigate whether the initial PEC indicates a resolving state of inflammation. We also evaluated serum tryptase levels to investigate the possibility of involvement of mast cell activity in AEP. RESULTS: Twenty-one AEP patients were included, and all patients improved within 10 days after corticosteroid treatment. The median initial serum IL-5 level among all patients was 561.0 pg/mL, which decreased to zero at 10 days of follow-up (n = 15, P < 0.001). The median initial serum tryptase level (detectable in 20 of 21 patients) was 3.7 ng/mL and decreased to a median of 1.1 ng/mL at 10 days of follow-up (n = 15, P < 0.001). The initial serum IL-5 and C-reactive protein levels were positively correlated (P = 0.009, r = 0.556), and the initial serum IL-5 level was inversely correlated with the initial PEC (P = 0.004, r = -0.603). CONCLUSIONS: Our data suggest that IL-5 is an important cytokine involved in the recruitment of eosinophils from peripheral blood into the lungs, that an initially elevated PEC is associated with a resolving state of inflammation, and that mast cells are potentially involved in the inflammatory process of AEP.
Authors: Aubri M Waters; Hyun J Park; Andrew L Weskamp; Allyson Mateja; Megan E Kachur; Jonathan J Lyons; Benjamin J Rosen; Nathan A Boggs Journal: J Allergy Clin Immunol Pract Date: 2022-01-12