Four days ago, a textbook case of pityriasis rosea walked into my room. Well, technically it was the girl who walk in…the rash was just a hanger-on. But to me, the rash was everything.
The more I looked, the more textbook it became. It was as if a Murtagh’s patient education handout had grown legs and a ponytail.
The lesions weren’t just red—they were salmon-pink. Salmon-pink, I tell you.
If an Atlantic salmon had leapt into her T-shirt and flopped around in a “Christmas tree” pattern for a few minutes before being sustainably released back into the ocean, those lesions could not have looked more classic.
“And I don’t suppose that oval patch on her back appeared 7-14 days ago did it, Dad? Goodness, see how the scales attach to the outer border of this herald patch like a collaret? Your daughter has become a thing of rare beauty Mr Smith! A textbook case.”
Note to self: it is more exciting to diagnose a textbook case than to father one. Beauty, as it turns out, is only skin deep.
Addendum: the modern man neither knows nor cares what a collaret is, which is somewhat of a shame. The dapper legacy of the early dermatologists has been supplanted by the drab business tie.
Back to textbook cases, however. Have you noticed how few there are about, these days?
Not just rashes, but all the classics seem to present rather half-heartedly.
Even when I do occasionally diagnose something with an eponymous title, it never seems to possess even half of the features described at length by Drs Conn, Monteggia, Reye or Erb.
Physicians were superbly specific back then. Diseases always had a triad of symptoms at worst, and the wonderful ones sported a baker’s dozen of things I wouldn’t even know how to look for, let alone find.
Our British and German predecessors would do things like scratch livers and listen for fremitus, then tell everyone about it in the hope that one of their medical students would eventually write a thesis and name the syndrome after their old professor.
My first ever textbook case, early in my intern year, falsely encouraged me to assume these things would continue throughout my career, just as the ancients described them.
It involved a kid with two weeks of fever, conjunctivitis, peeling skin on his palms and soles, and about four other criteria for Kawasaki’s Disease that I could probably name for you after a quick google. He had a strawberry tongue in the traditional sense, long before that referred to accidentally biting into a needle.
I’ve seen plenty of kids with fever since, and looked at a lot of tongues, but they always appear less strawberry and more pink, as if a salmon had got there first.
The fact that I so rarely see textbook cases has recently become ironic, because I now edit a medical textbook. Plenty of pathognomonic triads of symptoms printed on those pages, but I’m lucky if I even get to see a dyad in real life.
I’m even thinking of writing a list of “monads” for lazy diagnosticians. Spot your first collaret and it’s game over.
A kid with a fever? Textbook—that’d be Kawasaki’s.