Correlation between Pneumonia Severity and Pulmonary Complications in Middle East Respiratory Syndrome

Park, Wan Beom; Jun, Kang Il; Kim, Gayeon; Choi, Jae-Phil; Rhee, Ji-Young; Cheon, Shinhyea; Lee, Chang Hyun; Park, Jun-Sun; Kim, Yeonjae; Joh, Joon-Sung; Chin, Bum Sik; Choe, Pyeong Gyun; Bang, Ji Hwan; Park, Sang-Won; Kim, Nam Joong; Lim, Dong-Gyun; Kim, Yeon-Sook; Oh, Myoung-don; Shin, Hyoung-Shik

The present study has several limitations. First, the patients with underlying lung diseases and impaired lung function may have more severe MERS pneumonia. The patients with severe pneumonia had more underlying lung diseases, though the difference was not significant. However, even after adjusting for underlying lung diseases and smoking, the correlation between the MERS pneumonia severity and lung function impairment was significant. Second, because we defined pneumonia as infiltration on chest X-ray, we may classify a patient with mild pneumonia in the group without pneumonia. In fact, radiological sequelae on chest CT was observed in approximately 25% of the patients without pneumonia. Third, only 50% of the eligible MERS-CoV infected survivors were enrolled, which may not represent all of the MERS-CoV survivors in Korea. Forth, no baseline pulmonary function or CT scans were not available. Lastly, our definition of severe pneumonia as requirement of oxygen therapy may be broad and subjective. Ventilator care or mortality may indicate the patients with more severe pneumonia, although small number of patients hampered further classification in this study.