title: Transmission electron microscopy of sputum deposition in the diagnosis of pulmonary alveolar proteinosis.
abstract: OBJECTIVE
  To clarify the diagnostic value of sputum in pulmonary alveolar proteinosis (PAP) through transmission electron microscopy (TEM) of sputum deposition (SD).
  
  
  METHODS
  Eleven SD samples and 9 bronchoalveolar lavage (BAL) sediments from a PAP group including 11 patients were observed by TEM and compared with sputum direct smear, BAL cytology, and lung biopsy histopathology. Eleven healthy adults were chosen as controls.
  
  
  RESULTS
  The 11 sputum smears from the PAP group showed no diagnostic component, but TEM of SD revealed 7 of 11 samples had many myelin-like lamellar bodies with degeneration in the cytoplasm of macrophages, alveolar epithelial cells, and extracellular spaces, which suggested PAP. Especially, 2 patients on whom lung biopsy could not be performed and who failed to be diagnosed by BAL fluid were finally diagnosed by TEM of SD. TEM of BAL sediments showed 7 of 9 cases had diagnostic myelin-like lamellar bodies. No statistical significance was found between BAL fluid and SD by TEM. The control group didn't show diagnostic components by cytology or TEM of SD.
  
  
  CONCLUSIONS
  TEM of SD is an important noninvasive diagnostic method especially for patients against lung biopsy and BAL.
authors.affiliation: Tongji Hospital, Tongji University School of Medicine, Pathology, Shanghai, China.
authors.forename: Xianghua
authors.initials: X
authors.lastname: Yi
authors.forename: Huiping
authors.initials: H
authors.lastname: Li
authors.forename: Yu
authors.initials: Y
authors.lastname: Zeng
authors.forename: Xia
authors.initials: X
authors.lastname: Fang
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
authors.forename: Hanjing
authors.initials: H
authors.lastname: Lv
authors.forename: Benfang
authors.initials: B
authors.lastname: Luo
authors.forename: Zongmei
authors.initials: Z
authors.lastname: Zhang
authors.forename: Haiqing
authors.initials: H
authors.lastname: Chu
authors.forename: Xuyou
authors.initials: X
authors.lastname: Zhu
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology / Q000601:surgery; D008297:Male; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D008875:Middle Aged; D009186:Myelin Sheath / Q000648:ultrastructure; D011649:Pulmonary Alveolar Proteinosis / Q000175:diagnosis* / Q000601:surgery; D011650:Pulmonary Alveoli / Q000648:ultrastructure; D013183:Sputum / Q000166:cytology*