Rapid development of severe interstitial pneumonia caused by epoprostenol in a patient with primary pulmonary hypertension

A young woman with primary pulmonary hypertension developed severe interstitial pneumonia (IP) 5 days after induction of epoprostenol infusion. Although the pathogen involved was not identified, her IP was initially responsive to steroids, and discontinuation of steroid therapy caused the redevelopment of IP. After intensive treatment, including steroid therapy and inhaled nitric oxide, epoprostenol was successfully switched to prostaglandin E₁ infusion and she recovered. Epoprostenol infusion can cause a rapid severe IP, even soon after the induction of therapy. Clinicians should keep this syndrome in mind, especially when treating a severe case of IP.