Chronic pulmonary infection with Stenotrophomonas maltophilia and lung function in patients with cystic fibrosis

Background The clinical consequences of chronic Stenotrophomonas maltophilia infection in cystic fibrosis (CF) patient are still unclear. Method All patients treated in the Copenhagen CF centre (N=278) from 1 January 2008 to 31 December 2009 were included. Each patient chronically infected with S. maltophilia for at least 2years without any other chronic Gram-negative infection were matched to two non-infected CF controls. Results Twenty-one patients were chronically infected with S. maltophilia during the 2-year study period. Fifteen were infected for at least 2years. The patients in the S. maltophilia group had a steeper decline (-3.2%/year vs. -0.3%/year) in FEV1 compared to the non-infected CF controls (P=0.03). The rate of decline was the same as observed 3years before the patients became chronically infected. Discussions Chronic infection with S. maltophilia does not lead to a steeper decline in lung function when compared to the period before chronic infection.