The patient who returns from vacation with a fever is often a diagnostic dilemma. Unfortunately, up to 1 in 5 travelers to the developing world will get one within a few weeks of their trip. So how do you come up with a logical, evidence based diagnostic workup for a fever of unknown origin?
Thankfully, these authors reviewed the literature and came up with an easy to follow algorithm to work up a patient. It includes:
- Taking a detailed history
- Dates of travel
- Exposures (Food, water, sex, animals, sick people, INSECTS)
- Prophylaxis, either pretravel or during
- Illnesses during the trip, and medications
- Exposures after travel, as not all fevers come from the travel itself
- Performing a thorough physical exam
- Abdomen for hepatosplenomegaly
- Eyes for conjunctivitis
- Lymph nodes
- Skin for rose spots, maculopapular rashes, petechiae, or purpura
- Neurologic for AMS
- Specific initial lab tests
- CBC with manual diff
- Chemistries and LFTs
- Pancultures: stool, urine, blood
- Thin and thick blood smears
- Knowlege of geographic distribution of diseases
- Dengue and malaria are widespread
- Plasmodium vivax in the New World, P. falciparum in Africa, and non-P. falciparum in Asia
- Rickettsia, schistosomiasis, and filariasis in Africa
- Enteric fevers (typhoid and paratyphoid) are common in South Central Asia
- Knowlege of incubation period for diseases
Sadly, most of the evidence is consensus level or worse, so expect a lot of atypical presentations and results. It does make sense to not just fly off the handle and start ordering West Nile titers on everyone, but instead having a straightforward process to do it. They show this with three case vignettes that are great for adapting into some of your own simulation cases.
One last comment I have is that this paper is open access. That way, everyone can learn that a tourniquet test for dengue involves pumping a blood pressure cuff up to halfway between the patients systolic and diastolic pressure. It’s positive if they’ve got more than 20 petechiae/inch [square inch? -JH].
Fever in Returning Travelers: A Case-Based Approach
After I can no longer see her
she says to me For a while there is all
that asking about how the body becomes
itself as it goes and what it is becoming
what is happening to it where it is going
step by step one moment at a time
and then all that falls aside like a curtain
and the body is gone with its worn questions
hollow joints marrow and breath and instead there is
the way whatever lived in it goes on as itself
neither before nor after neither moving nor still
and while the body was going somewhere
the way was there to begin with in the feet themselves
wherever they went and you know the sound
- W. S. Merwin
And in this space we leave no trace.
I trail off into a slightly awkward silence that the mechanic cheerfully fills. I realise that what I’ve done is akin to what my patients frequently do; I’ve come into the car emergency department (well, my local garage) with a preconceived idea of what’s wrong because I’ve “spoken to Dave.” I could equally have “googled it” or “had a friend who had the same problem.” I feel a building empathy for the chap in front of me who has almost certainly stripped down more wheel bearings than I’ve inserted cannulas, yet who manages to indulge my ramblings. He does so because it’s part of his job not to offend the customer, just as much as it is to actually work out why my car is making more noise than an angry swarm of wasps in a bass drum.
As I sit there waiting to find out if Dave was right (he wasn’t), watching anxious customer follow anxious customer, I begin to see frequent parallels between the mechanic’s job and my own. He listens to symptoms (“She’s knockin’ when I go over a bump” or “She’s pulling to the left when I brake”) and he clarifies detail: “Did you hit the curb parking?” I can see him making a differential diagnosis in his mind as he walks off into the workshop to begin the initial investigations. The customer waits nervously, wondering how serious it is (how many columns will be on the final invoice.) The mechanic checks the car for dangerous faults (“…of COURSE your 24-year-old weight-lifter’s pleuritic chest pain is probably musculoskeletal, but you wouldn’t want to miss a P.E. Where’s that link to the Wells score again?”) and then has a look at the more likely stuff. He also humours me by checking out the wheel bearings, not because he thinks they’re the likely source of my noisy ride but because he knows I won’t be happy until he’s allayed my concerns.
Finally he comes to a diagnosis (“the tracking’s out and your rear wheels are wearing unevenly”) and proposes a treatment plan (“New tires and a quick go on the machine that makes sure all 4 wheels are pointing in the same direction, at least until you hit that curb again…”) In my case it’s easy; no complicated jargon, no debate about the cause of my problem, a relatively cheap solution and a high chance of success. But what about the unfortunate chap after me? He had an intermittently illuminating ABS light.
The mechanic patiently explained that unless the light came on whilst he was in the garage, investigating the multitude of possible causes would be drawn out, expensive and potentially fruitless. I couldn’t help but think back to the 24-year-old weight-lifter again. More specifically, I was remembering the inner monologue that occurred whilst I wrote my notes; that wonderful breathing space in any emergency physician’s day where you actually get a chance to think. “Of course it’s ALMOST certainly musculoskeletal, but he IS describing sudden onset pleuritic chest pain… What’s his Wells score? Good, low risk… Oh, bugger, his D-dimer’s up. I KNEW it would be, he said he had a snotty nose. Oh, thank goodness, I can PERC him… Excellent, PERC negative, I can discharge. Wait, what about pneumothorax? Better get a chest x-ray, just in case…” In medicine, and particularly in the emergency department, we’re comfortable balancing probability and risk. However, it took me longer to learn how to explain this to the anxious young lady with the non-specific abdominal pain, the normal observations and the soft belly than I care to admit. I know perfectly well that her pain will almost certainly dissipate as inexplicably as it arrived and if it doesn’t then we’ll have plenty of time to act on her worsening symptoms before anything untoward happens. However, convincing her of this fact at 3am is always a task requiring rapport, finesse and careful safety netting advice.
As I hear my mechanic put yet another anxious patient at ease (“It’s probably just smoking because it’s a diesel. They always run a bit dirty and if it’s your head gasket that’s going then you’ll get plenty of warning. Just keep an eye on the oil and make sure it doesn’t turn milky.”) I wonder where he developed the consultation skills that I’ve worked on my whole career. I’m relatively sure that nowhere in his training was there a session labeled “Simulated Customer Encounter” or “Breaking Bad News”, yet he manages it like a seasoned, kindly, greying physician who appears to have all the time in the world in the middle of a busy medical ward round.
Perhaps if we’d spent less time ensconced amongst the pillars of books with our noses buried in the latest journal and just a little more time chatting to Dave we wouldn’t need lectures to remind us how to talk to people.
Now, if only I knew my camshaft from my timing belt then I might even be ready for a career change.