Really. What Else Could It Be?
Mark Crislip
Quos Deus vult perdere, prius dementat (Those whom God wishes to destroy, he first deprives of reason) US Motto 2020-2022
This isn't going to be a COVID entry, and the quote has nothing to do with what follows. I was going to modify it to suggest being smug about one's diagnostic abilities is a sure path to disaster (Those whom God wishes to destroy, he first makes diagnostically smug). But I'm one smug sob at times, and, hey, what is the point of false modesty? Sometimes I do know what I am doing.
If you include my fellowship years, this is my 35th year in the ID biz. And I will let you in on a little secret if you promise not to tell anyone.
ID just ain't that hard anymore. Every consult has three questions that need answering: what do they have, why do they have it, and how best to treat it. I can usually figure that out in about 10 minutes. Even with the most complicated case, if you can separate the wheat from the chaff, it can generally be figured out in under 30 minutes. The rest of the consult is dotting t's and crossing i's, making sure you don't get blindsided by something unexpected. You have to be complete even when you have the answer upfront. Just in case.
You have probably noticed that ID docs do love to brag about much time they spend on a case, but it is time mostly spent reviewing information that doesn't matter. The vast majority of cases can be figured out in 10 minutes and summed up in a sentence or two if you know what is and is not relevant to the case at hand. But it took me 20 plus years, a quarter of my life, to get to that point. Until then, ID was hard.
As a fellow and resident, I remember how my ID attendings would generate an extensive differential diagnosis for cases but never commit. I always construct three lists for every patient. What they have. What I don't want to miss, even if unlikely if it could kill/harm the patient. And what is the cool diagnosis?
But I like to commit to a diagnosis. I love it when the venn diagram of the three lists has the same diagnosis at the top. Frequently in error, never in doubt, that's my motto. But as I have mentioned in the past, everyone remembers Babe Ruth pointing to right field and hitting a home run. No one remembers he led the league in strikeouts. So I commit. And it impresses the hell out of people when you are right,
Case in point, an FUO.
Four months of roughly one a week rigors, fever, sweat.
CBC/Comp/Blood cultures/CT CAP as an outpatient all normal except for a mild anemia.
So right away, any number of infections, presuming it is infection, are off the table. Few diseases go on that long, and with that pattern. Two, maybe three,
PMH: recent Bells palsy.
Now we are down to one possible disease.
Further questioning shows he visits the US NE frequently, and while he does not remember any tick bite, his Bells palsy was evaluated, and he had a positive Lyme serology, which had been treated.
So in about 8 minutes, I was down to the one disease this was likely to be. Ticks spread more than one disease with a bite. So.
Babesia?
Malaria was also on the list, but a case of suitcase malaria seemed less likely. Suitcase malaria is where an infected mosquito hitches a ride in a suitcase and infects someone in a non-endemic area. I have yet to see a case.
I did the rest of the usual H&P to be complete. Nothing. No other exposure history to put him at risk for odd infections.
So sent off a thick and thin smear and bingo was his name-o. Babesia. The first case that I have ever diagnosed.
But really, what else could it be? See? ID is simple. After spending most of your adult life at it
He got all better on Babesia therapy.
Rationalization
Origin and prevention of airport malaria in France https://onlinelibrary.wiley.com/doi/10.1046/j.1365-3156.1998.00296.x.
Coinfection by the tick-borne pathogens Babesia microti and Borrelia burgdorferi: ecological, epidemiological and clinical consequences https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4713283/