False-positive Elevation of Beta-D-glucan and Aspergillus Galactomannan Levels Due to Mendelson's Syndrome after Rice Aspiration

Both 1,3-beta-D-glucan (BDG) and galactomannan (GM) are polysaccharide components of the fungal cell wall. Although elevated levels of serum BDG and Aspergillus GM suggest invasive fungal infection or Pneumocystis pneumonia and aspergillosis, respectively, it is also necessary to consider the possibility of false-positives. We herein report a 68-year-old man with marked elevation in serum BDG and GM levels accompanied by Mendelson's syndrome after rice aspiration. With the improvement of Mendelson's syndrome, his serum BDG and GM levels decreased. The false-positive serum BDG and GM findings may have been due to his aspiration of food containing them. It is important to take a detailed history of aspiration in addition to making a conventional differential diagnosis in patients with pneumonia with elevated serum BDG and GM levels.