Bloodstream infections among patients treated with intravenous epoprostenol or intravenous treprostinil for pulmonary arterial hypertension--seven sites, United States, 2003-2006.

Pulmonary arterial hypertension (PAH) is a life-threatening disorder characterized by elevated pulmonary artery pressure and pulmonary vascular resistance. Continuous infusion of a prostanoid, which acts as a vasodilator and anti-proliferative agent, is indicated in the treatment of patients with severe PAH. Two prostanoids are approved for intravenous (IV) use in the United States: epoprostenol (epoprostenol sodium [brand name Flolan], Gilead, Foster City, California) and treprostinil (treprostinil sodium [brand name Remodulin], United Therapeutics, Silver Spring, Maryland). These drugs are administered to PAH patients at hundreds of treatment centers in the United States. In September 2006, CDC received a report from a PAH specialist of a suspected increase in the number of gram-negative bloodstream infections (BSIs) among PAH patients treated with IV treprostinil. CDC conducted a retrospective investigation with the assistance of several state health departments and the cooperation of seven PAH treatment centers to determine the relative rates of BSI in a sample of patients treated with IV treprostinil and IV epoprostenol during 2003--2006. This report describes the results of that investigation, which indicated that, based on combined data from seven separate PAH treatment centers, pooled mean rates of BSI (primarily gram-negative BSI) were significantly higher for patients on treprostinil than for those on epoprostenol. The results do not suggest intrinsic contamination of IV treprostinil as a cause of the infections; the difference in rates might have been caused by differences in preparation and storage of the two agents, differences in catheter care practices, or differences in the anti-inflammatory activity of the agents. Health-care providers who care for PAH patients should be aware of these findings. Further investigation is needed to determine the causes of the different infection rates at centers where this was observed and to determine whether such a difference exists in other PAH treatment centers.