Why is it so difficult to evaluate faecal microbiota transplantation as a treatment for ulcerative colitis?

Faecal microbiota transplantation (FMT) has recently re-emerged as a viable therapeutic option for colonic disorders. Its efficacy has been proved in the treatment of Clostridium difficile infection which has encouraged research into the use of FMT for other disorders involving gut dysbiosis, such as ulcerative colitis (UC), a chronic inflammatory disease characterized by relapsing and remitting colonic inflammation. Although the FMT protocol for C. difficile treatment is well established, there are numerous additional factors to consider when applying FMT to treat inflammatory diseases. Various studies have attempted to address these factors but technical inconsistency between reports has resulted in a failure to achieve clinically significant findings. Case reports of FMT in UC have shown favorable outcomes yet demonstrating these effects on a larger scale has proved difficult. The following review aims to explore these issues and to analyze why they may be hindering the progression of FMT therapy in UC.

'Lemonade Legs': Why do Some Patients Get Profound Hypomagnesaemia on Proton-Pump Inhibitors?

Proton pump inhibitors (PPIs) are widely used though an association with hypomagnesaemia and hypocalcaemia has only been described since 2006. Patients typically present after years of stable dosing with musculoskeletal, neurological or cardiac arrhythmic symptoms, but it is likely that many cases are under-recognised. Magnesium levels resolve rapidly on discontinuation of PPI therapy and hypomagnesaemia recurs rapidly on rechallenge with any agent in the class. The cellular mechanisms of magnesium homeostasis are increasingly being understood, including both passive paracellular absorption through claudins and active transcellular transporters, including the transient receptor potential channels (TRPM6) identified in the intestine and nephron. PPIs may alter luminal pH by modulating pancreatic secretions, affecting non-gastric H+K+ATPase secretion, altering transporter transcription or channel function. A small reduction in intestinal absorption appears pivotal in causing cumulative deficiency. Risk factors have been associated to help identify patients at risk of this effect but clinical vigilance remains necessary for diagnosis.