The Medical Journal of Record The New York Times. The link is to a gift article. has an excellent story on Kawasaki disease out today which reminded me of Balkan endemic nephropathy, another rare disease with an unusual and infectious disease-like distribution. Note that prevalence and distribution are where the similarities end. Kawasaki disease is a vasculitis (inflammation of the blood vessels) that affects children and young adults. Balkan endemic nephropathy caused your kidneys to shrivel up and stop working, and affected the middle-aged and the elderly. It had no known cause back when I was in medical school (which was — gasp — 20 years ago), but it has since been tied to accidental consumption of a certain plant. Well, accidental in the Balkans but intentional in China, where it was used in some traditional medicines and could cause “Chinese herbs nephropathy”, which was like the Balkan version on speed. Note that I am referring to both BEN and CHN in the past tense, but should probably temper my enthusiasm: even though we know what’s causing them and how to prevent them, their prevalence has decreased but is not zero.
The genetic revolution has been great for many aspects of medicine, but it has also made us a bit lazy. The promise of the late 1990s and the early 2000s has been that we would fine the genetic cause of most diseases, and would be only a step away from solving them. While we certainly found many genetic disorders, most of the are in the ultra-rare category and tied to newly-established diseases that were previously only described as syndromes. The “big” diseases — hypertension, type 2 diabetes mellitus, major depression and the like — are as unknown as ever, their cause described as “multifactorial” which is code for “we don’t know”. Stomach ulcers were also thought to be multifactorial until we found out they were mostly caused by a bacterium. A similar thing seem to be happening with multiple sclerosis, which seems to be caused by a virus, one that was mostly thought to be an unavoidable nuisance but is now a vaccine target.
But haven’t we already discovered all the big bad bugs? I sincerely doubt it. We have trouble identifying even larger organisms Also a gift link, this time to The Washington Post. I’m on a roll today. — there could be hundreds of disease-causing creatures and substances that we don’t yet know about because we can’t see them, can’t grow them, and/or don’t know where to look. And we terrifyingly bad at looking for anything but the obvious — there are parts of our own anatomy that we’ve discovered just recently.
So, I know that we will find the cause of Kawasaki disease and can only hope that it will be soon. I also hope that we will find the one main cause of the obesity epidemic. Add in essential hypertension and psychiatric disorders in there. Much money has been spent on discovering the genetic factors of these diseases. Now that we know that genes play but a small part in most of them, maybe it’s time to reallocate the funds.