title: An unusual postoperative pneumonia.
mesh_terms: D000368:Aged; D002763:Cholecystectomy; D005260:Female; D006801:Humans; D011022:Pneumonia, Rickettsial / Q000209:etiology*; D011183:Postoperative Complications / Q000209:etiology*; D009956:Psittacosis / Q000150:complications*