Presented are 2 cases of death from pulmonary alveolar proteinosis (PAP). Within the past 2 years, there have been 2 cases of rare nonneoplastic lung disease that consists of the filling of the alveoli of the lung by a periodic acid–Schiff stain-positive lipoproteinaceous material. This condition bears a certain resemblance to interstitial lung disease and/or Pneumocystitis jirovecci infection of the lungs. The presented cases were clinically diagnosed as interstitial lung disease. In the first case presented, the decedent was admitted to hospital with diagnosis of pneumonia but died in hospital despite observation and treatment. Autopsy examination revealed that instead of an infection, there was amorphous granular eosinophilic proteinaceous fluid in irregular clumps, with scattered foamy macrophages and cholesterol clefts and cracks in the lung alveoli. The second case was suspected of electrocution. There were no findings pointing to or against the possibility of electrocution, whereas the alveoli and terminal bronchioles were filled with amorphous granular eosinophilic lipoproteinaceous substance. The alveolar structure was well preserved, and the interstitium had no or mild chronic inflammatory cells. In both cases, the lipoproteinaceous material stained deep pink with periodic acid–Schiff stain. The gross and microscopic examination in the second case also signified pulmonary alveolar proteinosis.
The following report describes 2 cases of this uncommon disorder, with cause of death confirmed by postmortem examination.