Women with cystic fibrosis do not live as long as men, but the survival disadvantage does not develop until after puberty. A Dublin research group postulated that the reason for the poorer prognosis of women with cystic fibrosis is that high circulating oestradiol levels affect growth of mucoid Pseudomonas aeruginosa. The group performed in vitro studies which showed that long-term exposure of P. aeruginosa to oestradiol resulted in increased alginate production and the development of early mucoid morphology. Oestradiol levels vary with the menstrual cycle, and the Dublin group were able to show that exacerbations of cystic fibrosis with mucoid Pseudomonas were significantly more common at the time of high oestradiol levels. They were also able to review the national cystic fibrosis registry and show that oral contraceptive use was associated with lower use of antibiotics. This intriguing series of studies suggests that the oral contraceptive pill might protect against exacerbations with mucoid Pseudomonas, a hypothesis that should be tested in a randomised controlled trial.
Reviewers: Nick Wood, firstname.lastname@example.org; David Isaacs, Children's Hospital at Westmead.