My first exposure to clinical dermatology consisted of a month of Friday morning skin clinics during my second year of pediatric residency. Then, as now, skin disease was judged too unimportant to be taught to medical students.
Three volunteer dermatologists slumming from Manhattan supervised—two men and a woman. Their stylish dress clashed with the dingy decor of a Bronx city hospital OPD. Between patients, they spoke of cars.
My first patient sat on a gurney at the back of an alcove separated from the corridor by a curtain. Because I had no idea what she had, my presentation must have been brief. The three dermatologists followed me back in and took a casual look. Turning to leave, one of the men said, "Pityriasis rubra pilaris." The others nodded, exiting the alcove.
I was astonished. How could they just look at something and know what it was? Much later, I learned their twin secrets:
▸ Knowing from experience.
▸ Making up what you don't know.
What prompted this small reminiscence was a recent essay in the New England Journal of Medicine, "The Demise of the Physical Exam" (2006;354:548–51). In the essay, Dr. Sandeep Jauhar recounts a medical school incident in which he missed an aortic dissection by failing to note that the patient's blood pressure was higher on one side than the other. The way he remembers physical diagnosis instruction sounded familiar: "The preceptor was an intense but likable oncology fellow who was clearly ambivalent about the value of the skills he was teaching. … Even as he went through the motions of teaching physical diagnosis, he appeared to be dismissing it."
Dr. Jauhar notes several reasons for this dismissal, including lack of time to do a proper physical and the noisy distractions of a hospital milieu. The most important reason, however, is the fact that diagnostic tests just do a better job at making diagnoses. This is true even in comparing chest x-rays with auscultation, and new diagnostic technology of mind-bending sophistication only makes the disparity more glaring. Compared with an MRI, a physical exam seems like something from grandma's attic.
One field of medicine remains, however, where physical examination is alive and well: ours. Most dermatologists with any experience do every day what my long-ago preceptors so amazed me with: walk in, look, diagnose. We don't do a lot of tests. We don't have a lot of tests to do.
Last week, I recorded patients' diagnoses and lab tests on a random day. Of 46 patients, 23 had rashes (acne, psoriasis, and so forth); 5 had bacterial or fungal skin infections; 5 had warts; 11 had lesions of some sort; and 2 had cosmetic-related questions.
The lab test tally for that day was one bacterial skin culture, one fungus culture, one KOH prep, blood tests for a patient taking isotretinoin, and three biopsies.
This seems typical of one of our days. Most of the time, we glance and know at once what we're dealing with. (Managing it is another story.)
For every lesion we biopsy, people show us 20 we diagnose by inspection (visual or dermoscopic). Rashes are mostly clear cut. When they aren't, we biopsy. (And how often does the biopsy of a rash give us a decisive answer?) For many infections, cultures are confirmatory, if not redundant. Drug rashes? Viral exanthems? Clinical diagnoses.
Medical students find all this as weird as I did when first exposed to it. They're so used to watching people order tests—to diagnose, placate senior staff, or ward off phantom attorneys—that their clinical skills atrophy before they develop; they lose it even before they use it. When I ask my students what their impression is of a rash, their eyes widen in a silent plea: You mean I should know just by looking?
Well, yes. As is true of any skill, you can develop it, with instruction and practice.
Without a dermatology elective in school, many physicians carry this primal fear of skin disease indefinitely. "Skin makes me nervous," they tell patients. "See the dermatologist." They think our skills are a little occult.
We dermatologists shouldn't take too much credit for our archaic clinical virtuosity, such as it is. To a large extent, we don't rely on tests because we don't have tests to rely on. If we had more crutches, we would lean on them as much as anyone else does. Our patients would insist.
Meantime, however, we practice in a manner that is alarmingly similar to the way our remote clinical ancestors did.