Fans of The Rational Clinical Examination, once the best series in any medical journal, are having their patience tested a bit of late. Does This Patient Have Erythema Migrans? is a question of prior probability and pattern recognition, with no gold standard that allows us to answer with a tick. In fact there are two tick-borne diseases which can cause erythema migrans, Lyme disease and Masters disease (also called STARI, southern tick-associated rash illness). The causative agent of the first is Borrelia burgdorferi, not discovered until 1982, while the second is probably caused by B lonesteri. Erythema migrans is not often seen in the UK, though British ticks have carried borrelias for ages, as someone proved by examining old samples from the Museum of Natural History. I suppose they keep them there in tick boxes.

Now that renal physicians have emerged dazed and blinking from their labs and machines into the full light of mainstream medicine, what do we actually know about the importance of chronic kidney disease in relation to public health? Surprisingly little, it seems from this useful short piece on the gaps in the evidence. It seems to me that by concentrating on improving cardiovascular health we will also improve renal health, and that is about all we can do.