title: Dynamic changes of serum SARS-coronavirus IgG, pulmonary function and radiography in patients recovering from SARS after hospital discharge.
abstract: OBJECTIVE
  The intent of this study was to examine the recovery of individuals who had been hospitalized for severe acute respiratory syndrome (SARS) in the year following their discharge from the hospital. Parameters studied included serum levels of SARS coronavirus (SARS-CoV) IgG antibody, tests of lung function, and imaging data to evaluate changes in lung fibrosis. In addition, we explored the incidence of femoral head necrosis in some of the individuals recovering from SARS.
  
  
  METHODS
  The subjects of this study were 383 clinically diagnosed SARS patients in Beijing, China. They were tested regularly for serum levels of SARS-CoV IgG antibody and lung function and were given chest X-rays and/or high resolution computerized tomography (HRCT) examinations at the Chinese PLA General Hospital during the 12 months that followed their release from the hospital. Those individuals who were found to have lung diffusion abnormities (transfer coefficient for carbon monoxide [DLCO] < 80% of predicted value [pred]) received regular lung function tests and HRCT examinations in the follow-up phase in order to document the changes in their lung condition. Some patients who complained of joint pain were given magnetic resonance imaging (MRI) examinations of their femoral heads.
  
  
  RESULTS
  Of all the subjects, 81.2% (311 of 383 patients) tested positive for serum SARS-CoV IgG. Of those testing positive, 27.3% (85 of 311 patients) were suffering from lung diffusion abnormities (DLCO < 80% pred) and 21.5% (67 of 311 patients) exhibited lung fibrotic changes. In the 12 month duration of this study, all of the 40 patients with lung diffusion abnormities who were examined exhibited some improvement of lung function and fibrosis detected by radiography. Of the individuals receiving MRI examinations, 23.1% (18 of 78 patients) showed signs of femoral head necrosis.
  
  
  CONCLUSIONS
  The lack of sero-positive SARS-CoV in some individuals suggests that there may have been some misdiagnosed cases among the subjects included in this study. Of those testing positive, the serum levels of SARS-CoV IgG antibody decreased significantly during the 12 months after hospital discharge. Additionally, we found that the individuals who had lung fibrosis showed some spontaneous recovery. Finally, some of the subjects developed femoral head necrosis.
authors.affiliation: Department of Respiratory Medicine, Chinese PLA General Hospital, 28 Fuxing Road, Beijing, 100853, P,R, China. xielx@301hospital.com.cn
authors.forename: Lixin
authors.initials: L
authors.lastname: Xie
authors.forename: Youning
authors.initials: Y
authors.lastname: Liu
authors.forename: Baoxing
authors.initials: B
authors.lastname: Fan
authors.forename: Yueyong
authors.initials: Y
authors.lastname: Xiao
authors.forename: Qing
authors.initials: Q
authors.lastname: Tian
authors.forename: Liangan
authors.initials: L
authors.lastname: Chen
authors.forename: Hong
authors.initials: H
authors.lastname: Zhao
authors.forename: Weijun
authors.initials: W
authors.lastname: Chen
mesh_terms: D000914:Antibodies, Viral / Q000097:blood; D002681:China / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D005271:Femur Head Necrosis / Q000097:blood / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D010351:Patient Discharge / Q000706:statistics & numerical data; D011379:Prognosis; D011658:Pulmonary Fibrosis / Q000097:blood / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D011859:Radiography; D020127:Recovery of Function; D012129:Respiratory Function Tests / Q000706:statistics & numerical data; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology; D045169:Severe Acute Respiratory Syndrome / Q000097:blood / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology*
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G