Parainfluenza virus pneumonitis in an adult.

Parainfluenza virus uncommonly causes fatal giant cell pneumonia in immunocompromised infants and children. To our knowledge, this is the first adult case of parainfluenza virus pneumonia. A 77-year-old woman who was diagnosed as having small-cell carcinoma of the lung underwent chemotherapy. She died of lung edema. Analysis of her serum showed antibodies to parainfluenza virus types 2 and 3 at titers of 1:64 and 1:128, respectively. The postmortem examination revealed giant cell pneumonia, in which giant cells and detached alveolar lining cells had intracytoplasmic inclusions. On electron microscopic examination, the intracytoplasmic inclusions contained fuzzy-form nucleocapsids.