14 May 2012

Harrison's Ch. 251: "Approach to the Patient with Disease of the Respiratory System"

Perhaps you watched the film "Julie and Julia" a few years ago. It is partly about a blogger, Julie Powell, who spent a year making every recipe in Julia Child's best-known cookbook.

I am doing something similar (albeit less tasty and less likely to be made into a feature film starring Meryl Streep). I am in the process of reading Harrison's Principles of Internal Medicine in its entirety. Harrison's is a dense, 3,600-page, two-volume tome that is the closest thing to a bible in clinical medicine. I am reflecting upon some of its chapters during the year or so it takes me to finish. 

Although I should have been asleep, last night I was determined to get through another chapter of Harrison's. On a whim, I read "Approach to the Patient with Disease of the Respiratory System." The chapter describes the mechanisms of certain respiratory illnesses and instructs the doctor in how to use physical examination techniques and diagnostic tests to inform his diagnosis.

In a stroke of good fortune, today I evaluated a patient with a nasty cough that began a week ago. It hurt when she breathed deeply. I suspected pneumonia and pleuritis (inflammation of the outer surface of the lung).

I took a lengthy history, and posed some questions that must the patient must have found strange. I asked for a domestic travel history, to rule out the endemic mycoses (three pneumonia-causing fungi found only in particular parts of the country). I asked for her history of international travel, to rule out tuberculosis. I asked if she had pets, to rule out psittacosis (a pneumonia-causing bacterium transmitted from birds).

Then I performed my physical examination, paying particular attention to the lungs. My leading diagnosis became even more specific: a bacterial pneumonia of the left lower lobe of the lung, with pleuritis. My calling which lobe of the lung was affected is a bit like a billiards player calling the pocket where he's going to send the 8-ball. My confidence stemmed partly from my having read the relevant section in Harrison's the night before.

We took a chest X-ray, and sure enough, my diagnosis was on the money.

It was a proud moment because it was a big milestone. I've seen many patients, and I've suggested many diagnoses, but never before have I been able to learn whether my diagnosis was ultimately correct. The number of diseases I'm familiar with grows by the day. My hunches are becoming more accurate, and I'm asking patients the right questions more often.

It's fun to compare how I feel about my skill level now to what I wrote just four months ago. Although I still am far from being a doctor, I'm definitely getting the hang of this.