Thursday, 5 September 2013

Antibiotic exposure and coeliac disease

I know that sometimes I sound a little bit ungrateful on this blog when it comes to important scientific advances and what they have done for modern day humans. Take for example antibiotics (antimicrobials if you wish) and how they have revolutionised medicine over the past few generations. Without them, even relatively minor infections and injuries which are nowadays routinely treated with antibiotics could prove as fatal as they were in the centuries before their discovery. Antibiotics have saved countless lives.
Dinner is served... @ Wikipedia  

But, as with many medical advances, success can also have its down-side too; as we are all now warned about the growing tide of antibiotic resistance and how this threatens our new-found reliance on these almost 'miraculous' pharmaceutical products.

The realisation also that antibiotic use and their subsequent effects might also impact on important environments such as the delicate balance of micro-organisms which call us home in our deepest, darkest recesses is also growing in importance as per some very recent research (see here) on the potential hows and whys. Upsetting the balance of the various bacteria which reside in our gut (dysbiosis) following antibiotic use has been a topic appearing more than once on this blog in relation to conditions like autism (see here) and the inflammatory bowel diseases (IBDs) (see here). Indeed it is with such a relationship in mind with regards to another bowel related condition, coeliac (celiac) disease (CD), that this entry focuses on the paper by Karl Mårild and colleagues* (open-access).

The Mårild paper is free for all to read and so no need for me to go to deeply into the paper. Suffice to say that based on an analysis of some quite large numbers of people diagnosed with CD or small intestinal inflammation or CD serology defined as "a positive IgA or IgG AGA (antigliadin), EMA (endomysial), or TTG (tissue transglutaminase) test less than 180 days before or no later than 30 days after a normal biopsy (and with no prior or subsequent biopsy showing villous atrophy or inflammation)", there was an association found with prescription patterns for antibiotics in Sweden. Inevitably the discussion leads on to how antibiotics alter the gut microbiota and potentially too the risk of developing CD although the door is left open for a purely epiphenomenal explanation.

A quick trawl through PubMed reveals that this research group have some history looking at various factors potentially 'associated' with the onset of coeliac disease. A six-fold increased risk of CD in cases of Down syndrome (see here), elective c-sections potentially being linked (I've talked about this one before) but not so for serious psychological stress (see here) have all been mentioned. Certainly with that elective c-section link there is some possible connection to the recent work as per the function of the bacteria that vaginal birth puts baby into contact as it traverses the birth canal before hitting the bright lights of the real world complete with bacterial passengers.

I know some people are probably furrowing their brow at the moment whilst uttering the words 'correlation is not causation' as a result of the implication that antibiotic use (or over-use) might impact on the gut microbiome and onwards impact on risk of conditions like coeliac disease or IBDs. I'll reiterate again that a purely epiphenomenal explanation has not been ruled out by the authors or me.

That being said, knowing that our gut bacteria might be doing so much more than just aiding food digestion and other related tasks, research in pursuit of any connection with conditions like CD should continue. If only to offer potentially something more than just a lifelong gluten-free diet as a management option (see here** with the caveat that no medical advice is given or intended) or indeed to further all that non-CD gluten sensitivity chatter (see here).

Who knows it might even provide some further evidence for the routine use of probiotics following completion of an antibiotic course?

So then, "shooting at the walls of heartbreak"? Any warriors out there?


* Mårild K. et al. Antibiotic exposure and the development of coeliac disease: a nationwide case--control study. BMC Gastroenterology 2013, 13:109 doi:10.1186/1471-230X-13-109

** Smecuol E. et al. Exploratory, randomized, double-blind, placebo-controlled study on the effects of Bifidobacterium infantis natren life start strain super strain in active celiac disease. J Clin Gastroenterol. 2013 Feb;47(2):139-47. doi: 10.1097/MCG.0b013e31827759ac.

---------- Karl Mårild (2013). Antibiotic exposure and the development of coeliac disease: a nationwide case--control study BMC Gastroenterology DOI: 10.1186/1471-230X-13-109