Today I had a conversation with an old friend and he asked if I had any insight to cystic fibrosis from my readings. I had to say no — but stated that it would be worthwhile to examine whatever research may apply.
Cystic fibrosis is a genetic disorder, so the initial assumption would be that it had nothing to do with the microbiota. From my readings, both the DNA of the body and the DNA of the bacteria that inhabits the body are inherited — so there is a possibility that it may take a double inheritance to cause the condition to develop fully. While altering the microbiota may not stop or prevent the disease — it may have an impact of the rate of progression or side-effects — this is the hypothesis that I am exploring in this post.
As a starting point in this 2010 article,Comparing the microbiota of the cystic fibrosis lung and human gut which states “the typically mutually beneficial relationships usually found in the GI tract from the injurious relationships in the CF lung.” This is a familiar situation of the disease altering the microbiotia, with the microbiotia then supporting the disease. This was illustrated in the diagram below.
For CF, this is reported in this 2004 article, Intestinal inflammation is a frequent feature of cystic fibrosis and is reduced by probiotic administration
The authors go on to say, “demonstrated that pathogenically important behaviors of Pseudomonas aeruginosa can be impacted by the presence of bacterial species that are routinely disregarded by most treating clinicians.” In terms of the general relationship (not CF specific), “association between changes in the composition of gut microbes and changes in the normal functioning of the nervous system” speaks to the neurological issues seen with the shift of the microbiota seen with Chronic Fatigue Syndrome.
The article does a nice discussion of some of the issues and ends with “The challenge that remains for the study both of chronic infections affecting CF airways and of gut microbiota is to construct theoretical frameworks in which the implications of these data can be understood.” – in other words, we have a concept but not sufficient evidence to suggest a study supported therapy.
Almost all of the studies raised the question that it is unclear if the effect is due to reduce inflammation because of the probiotics or because it inhibited the CF process.
- Lactobacillus Rhamnosus was found to improve CF patients    
- A non-CF study finding that Lactobacillus casei reduces Pseudomonas aeruginosa 
- Azithromycin and other antibiotics improves CF patients  
- The issue is always whether it is because they alter gut bacteria, or impact the other infections seen in CF.
What I would love to see is a well designed study done of CF patients with the two commercially available (and unusual) probiotics:
- Mutaflor (E.Coli Nissle 1917)
- Prescript Assist (mixture of 29 non-Lactobacillus species)