Herpes simplex virus pneumonia following mitral valve replacement.

We describe a rare case of a 79-year-old woman who developed herpes simplex virus pneumonia after mitral valve replacement. The patient showed persistent hypoxemia with bilateral glass-like shadows on chest radiography. Cytopathology examination of intratracheal secretions revealed herpes simplex virus infection. The patient, who improved gradually after acyclovir administration, was taken off the ventilator completely. Physicians should consider viral pulmonary infection to be a potential cause of unexplained hypoxemia that does not respond to conventional antibiotic treatment in critically ill, immunocompromised patients.