RT Journal Article SR Electronic T1 Decreased eosinophil counts and elevated lactate dehydrogenase predict severe COVID-19 in patients with underlying chronic airway diseases JF Postgraduate Medical Journal JO Postgrad Med J FD The Fellowship of Postgraduate Medicine SP 906 OP 913 DO 10.1136/postgradmedj-2021-139704 VO 98 IS 1166 A1 Chen, Dian A1 Zhang, Shuchen A1 Feng, Yuchen A1 Wu, Wenliang A1 Chang, Chenli A1 Chen, Shengchong A1 Zhen, Guohua A1 Yi, Lingling YR 2022 UL http://pmj.bmj.com/content/98/1166/906.abstract AB Background Several predictors of COVID-19 severity have been reported. However, chronic airway inflammation characterised by accumulated lymphocytes or eosinophils may affect the pathogenesis of COVID-19.Methods In this retrospective cohort study, we reviewed the medical records of all patients with laboratory-confirmed COVID-19 with chronic bronchitis, chronic obstructive pulmonary disease (COPD) and asthma admitted to the Sino-French New City Branch of Tongji Hospital, a large regional hospital in Wuhan, China, from 26 January to 3 April. The Tongji Hospital Ethics Committee approved this study.Results There were 59 patients with chronic bronchitis, COPD and asthma. When compared with non-severe patients, severe patients were more likely to have decreased lymphocyte counts (0.6×10⁹/L vs 1.1×10⁹/L, p<0.001), eosinopaenia (<0.02×10⁹/L; 73% vs 24%, p<0.001), increased lactate dehydrogenase (LDH) (471.0 U/L vs 230.0 U/L, p<0.001) and elevated interleukin 6 level (47.4 pg/mL vs 5.7 pg/mL, p=0.002) on admission. Eosinopaenia and elevated LDH were significantly associated with disease severity in both univariate and multivariate regression models including the above variables. Moreover, eosinophil count and LDH level tended to return to normal range over time in both groups after treatment and severe patients recovered slower than non-severe patients, especially in eosinophil count.Conclusions Eosinopaenia and elevated LDH are potential predictors of disease severity in patients with COVID-19 with underlying chronic airway diseases. In addition, they could indicate disease progression and treatment effectiveness.Data sharing not applicable as no datasets generated and/or analysed for this study.