December 9, 2022

Effectiveness of antipseudomonas antibiotics for pulmonary exacerbation of cystic fibrosis


According to the results of a retrospective cohort study published in Clinical infectious diseases.

Researchers in Seattle, Washington, analyzed medical records from the Cystic Fibrosis Foundation’s Patient Registry and Pediatric Health Information System dataset, collected between 2005 and 2018. Clinical outcomes of children and adolescents with cystic fibrosis have been evaluated after treatment for pulmonary exacerbations.

Patients were treated with 2 (n = 2123) or 1 (n = 455) antipseudomonas antibiotic intravenously. The median age of the patients was 16.1 years (interquartile range [IQR], 13.3-18.0) for those receiving 2 intravenous antibiotics and 16.2 years (IQR, 13.3-18.1) for those receiving 1 intravenous antibiotic; 44% and 46% were boys or men, and 75% and 63% were Caucasian, respectively. Reference percentage of predicted forced expiratory volume in 1 second (ppFEV1) was 78.8% (IQR, 62.8-91.5) and 74.9% (IQR, 60.0-87.8), respectively. In the previous 12 months, 40% and 54%, respectively, had received at least 2 antibiotics intravenously.

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Change of ppFEV1 was not significantly different between cohorts (inverse probability adjusted for treatment weighting [aIPTW], -0.84%; 95% CI, -2.25 to 0.56; P = 0.24) and was not returned 90% or more of the baseline (odds ratio [OR], 0.83; 95% CI: 0.61-1.13; P = 0.24) or the time to the next pulmonary exacerbation (risk ratio [HR], 1.04; 95% CI: 0.87-1.24; P = .69).

Compared with patients who received 2 intravenous antibiotics, patients who received 1 intravenous antipseudomonas antibiotic and 1 inhaled had an increased risk of future pulmonary exacerbation (RR: 1.31; 95% CI: 1.06- 1.63; P = .014).

Stratified by narrow and broad spectrum antibiotics, no significant difference between groups was observed for the change in ppFEV1 (aIPTW, 0.80%; 95% CI, -0.56 to 2.16; P = 0.90) or revert to 90% or more from baseline (OR, 0.99; 95% CI, 0.74-1.32; P = .93). Patients treated with narrow-spectrum antibiotics had a reduced risk of the following pulmonary exacerbation (RR: 0.86; 95% CI: 0.76-0.98; P = .021).

This study was limited by its retrospective design and the use of registry data that may include inaccurate or missing data.

The study authors concluded that there was little benefit from using 2 intravenous antipseudomonas antibiotics versus 1 for patients with pulmonary exacerbation of cystic fibrosis. Patients living with cystic fibrosis who received narrow-spectrum antibiotics were more effectively protected against future pulmonary exacerbations.

Disclosure: One study author reported affiliations with biotech, pharmaceutical, and / or device companies. Please refer to the original reference for a full list of author disclosures.


Cogen JD, Faino AV, Onchiri F, et al. Association between the number of intravenous antipseudomonas antibiotics and the clinical results of pulmonary exacerbations in pediatric cystic fibrosis. Clin Infect Dis. Published online June 8, 2021. doi: 10.1093 / cid / ciab525