Two recent papers have raised concerns about cats in households with cystic fibrosis (CF) patients. People with CF are at high risk for a range of complications because of their condition and the treatments that are required. Some complications can be life-threatening, so there’s lots of research into factors associated with disease in people with CF.

One of the recent studies (Morrow et al. Journal of Pediatrics 2014) looked at 703 kids with CF. As is fairly consistent with the general population, 47% lived with one or more dogs and 28% with one or more cats. Dog ownership was not associated with problems, but cat owners had an increased risk of developing nasal polyps. Nasal polyps are a common problem in people with CF, thought to be caused by allergy, infection and/or chronic nasal congestion. If there’s truly a link with cats, it’s logical that allergies would play a role. When analysis combined dogs and cats, pet owners were twice as likely to report wheezing compared to non-dog/cat owners; again, likely an allergic, not infectious, issue.

Fortunately, wheezing and polyps aren’t typically severe complications. A different situation is presented in a separate case report in Pediatric Respiratory Reviews (Pabary 2014). It describes a child with CF who had difficult-to-control symptoms that were thought to be exacerbated by a cat allergy. The child only improved when the cat was removed from the household.

Does this mean that pets should be removed from households with CF patients?

No, but it means that the cost-benefit balance needs to be considered. As the Morrow et al. paper states "Prospective studies are needed to confirm these associations and the potential psychosocial benefits of cat and/or dog ownership." Figuring out whether these relationships are real (i.e. causative) and determining what the risk of these complications means for an individual person compared to the potential benefits is the key. It’s not easy, and the cost-benefit will vary between households. That’s why there needs to be conversations between patients and their families, their healthcare provider(s) and their veterinarian. The Pabary case report indicates that pet removal is sometimes required, although that’s a rare situation – pet removal/surender needs to be very carefully considered and should not be a knee-jerk reaction (as it all too often is).

Photo credit: Tracy (click image for source)