What do you know about hepatitis E? Not a thing, in my case, before I read the editorial on p.949 accompanying this vaccine trial. It’s caused by a tiny RNA virus (HEV) and is endemic in various remote parts of the world. The vaccine is based on recombinant HEV protein and the successful trial was carried out in Nepal. It is not an easily transmissible disease, does not become chronic, and has a low case-fatality, so the chances are that you will not require the vaccine unless you are going boar-hunting in Mongolia. And now: what do you know about hepatitis D?
Quite a few drugs can cause an immune-mediated thrombocytopenia, as described in a helpful little introductory piece on p.891. In this study, the cause was vancomycin, an antibiotic which most of us rarely have occasion to use: on a more practical note, be aware that the commonest culprit drug is quinine, which most of us hand out readily as a cure for cramp, and some people like with their gin. I wonder if tonic water has ever caused IMTP?
If you have ever picked up a medical textbook from the late 1920s or 1930s, you will have found a variety of chronic diseases attributed to focal sepsis, for which a popular treatment was removal of the tonsils and the teeth. As antimicrobial drugs became available, the theory fell out of favour; but it was not entirely irrational since we know that chronic inflammation and inappropriate immune activation do indeed cause a variety of chronic diseases, though unfortunately they cannot be cured by a nice set of dentures. This London study demonstrates that there is a link between periodontitis and adverse markers of endothelial function: it can be corrected by treatment, though the clinical significance of these findings is uncertain.
A patient of mine recently went into rapid atrial fibrillation and nearly died of heart failure. The drug which saved her was amiodarone. She is now leading a near-normal life, though she will be wearing a sun-hat this summer. Amiodarone works by prolonging the duration of action potential, so cardioverted patients have a prolonged QT interval. The various drawbacks of amiodarone are well known to most of us and are well summarised here.