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A Medical Guide to House

Saturday, April 07, 2007

House Wannabe and the Case of the Real McCoy

Foreman: "Looks like they got the pheo out successfully. So. what now?"
House: "Clarence goes back to death row."
Foreman: "Just like that?"
House: "He's cured."
Foreman: "That tumor caused random shots of adrenaline, which obviously led to the rage attacks that made him become a murderer in the first place."
House: "By God, you're right! Let's call the surgeons. We gotta save that tumor; put it on the witness stand."
Foreman: "We could testify at Clarence's appeal."
House: "You smell that? I think that is the stink of hypocrisy. You wouldn't even consider the notion that Clarence's social upbringing was responsible for what he became, but now you're sprinting to the witness stand to blame everything on a little tumor."
Foreman: "A person's upbringing and their biology are completely different."
House: "Yeah. Because you only overcame one of them."
If you think back to Season 2, Episode 1, you might remember the story of Clarence, played by LL Cool J. Clarence was an inmate who had been put in jail on the charges of multiple counts of murder. Just prior to being brought into the Princeton-Plainsboro hospital, he was experiencing an episode of uncontrolled rage and hallucinations. During the course of the show, House discovered that Clarence suffered from a pheochromocytoma, a tumor of the adrenal gland that oversecretes adrenaline. Too much adrenaline in the body typically causes episodes of headaches, high blood pressure, sweating, and heart palpitations. House figured that in Clarence's case, the extra adrenaline was making him have episodes of rage. Foreman took this argument even further and claimed that perhaps Clarence should be acquitted for his murders because they may have been conducted during one of his raging episodes. The episode ends with Foreman saying that he planned to testify in Clarence's trial.

This argument at best spurious. I agree that it makes sense on a certain primitive level that excess adrenaline should cause a person to be violent. But that's it. There is no data anywhere that suggests that a pheochromocytoma can actually cause a person to be violent. In fact, even in forensic medicine journals, pheochromocytomas are acknowledged primarily for their ability to cause sudden death and panic attacks. As people who've suffered from panic attacks can tell you, the last thing a person who is having a panic attack is interested in is killing someone else.

So consider my surprise when I saw in the Washington Post today that "the real McCoys," renouned for their violent feuds with the Hatfields, have a hereditary disease that results in pheochromocytomas. Von Hippel-Lindau disease is apparently the cause of the violent history shared by members of the McCoy and Hatfield families, according to Dr. Revi Mathew at Vanderbilt University. Dr. Mathew says: "This condition can certainly make anybody short-tempered, and if they are prone because of their personality, it can add fuel to the fire."

An interesting statement, even if it is at least somewhat incorrect. Maybe he saw it on House?

posted by k-deep at 9:49 PM 4 comments

Tuesday, April 03, 2007

House: Great Diagnostician?

One of the premises of House as a TV show is that Dr. House is a diagnostic genius. As a character, House's drug-seeking behavior and terrible bedside manner is forgiveable only because he is able to traverse through obscure symptoms and come up with a unifying diagnosis. As one of my attending physicians told me, there are two ways of approaching an arbitrary set of symptoms: Occam's razor and Hickam's dictum. For medical purposes, Occam's razor states that a patient with two complaints (ie. headache and fever) is much more likely to have one disease entity that is causing both complaints as opposed to two different disease entities. Hickam's dictum, on the other hand, says that a patient with two complaints is more likely to have different causes for each symptom as opposed to one unifying disease process.

Historically, physicians whose names are revered today are those who applied Occam's razor to identify new diseases. There's Charcot's triad for cholangitis, Cushing's triad for increased intracranial pressure, Wernicke's triad of thiamine deficiency, and so on. An exceptional physician is someone who is able to decide when to apply Occam's razor and when to apply Hickam's dictum. There is actually an example of a misapplication of Occam's razor which is still mentioned in textbooks, known as Saint's triad, named after C.F.M. Saint, a South African surgeon (not to be confused with Dr. Sanjay Saint, who published a New England Journal of Medicine article about Saint's triad).
The legend goes that Dr. C.F.M. Saint saw a number of patients with diverticulosis, gallstones, and a hiatal hernia, and decided that there must be an underlying disease that explains all 3 of those symptoms. He did something that doctors love to do and attached his name to this series. As it turns out, diverticulosis, gallstones, and hiatial hernias are all fairly common medical conditions, and they're much more likely to occur due to their own etiologies than to a shared etiology.
One of the reasons that House appears to be such an exceptional diagnostician is that he is able to correctly apply Occam's razor and Hickam's dictum to the nth degree to diagnose even the most obscure of diseases.

But consider how House comes up with his solutions. A patient comes in with a vague complaint. This complaint leads to another complaint, which then leads to a seizure, allergic reaction, or organ failure resulting in the patient requiring intubation. Is this really top-notch care? To ask this question in a different way, what would take place in an "ordinary" top tier hospital?

Order of steps in on an ordinary medicine service:
1. Patient is seen in ER and sent up to the Medicine floor
2. Patient is evaluated by resident (and possibly a medical student)
3. Resident presents the patient's history, physical exam, and labs to the attending physician
4. Attending physician repeats pertinent aspects of history and physical exam and suggests changes to the resident's plan

In this case, substitute the word "resident" for "fellow" because Foreman, Chase, and Cameron are done with their residencies and are now working on their fellowships. As evident on House's team, things work a bit differently.

Order of steps (on House's team):
1. Patient is transferred to House's team from who knows where
2. One of the fellows (Chase/Cameron/Foreman) takes a history
3. One of the others does a physical exam
4. House comes up with a differential diagnosis consisting of 10 things and orders every single test needed to sort out which of the possibilities is actually present

House's differential diagnosis is typically fairly extensive, and in this regard, I think that House is admirably intelligent. It takes experience to be able to name common causes of a spectrum of symptoms, but many of the things that House spouts off (and even a lot of what Cameron says on the show nowadays) reflect a lot of time spent with textbooks (or UpToDate). My primary critique of House's techniques is the same one that was pointed out by Vogler in season 1. Every patient with an isolated symptom doesn't need a complete work-up. Financially (and in some sense medically), it doesn't make sense to work a patient up for an autoimmune disorder until a more likely cause has been ruled out. I think physicians have an inner longing to be able to just order every possible test all at once, but this can be irresponsible, depending on the medical setting. A simple example of this is the difference between telling your family medicine doctor that you're having a headache and telling an ER physician the same. In the first case, you're likely to be treated for migraines, whereas in the second case, you're likely headed to the CT scanner for a head CT.

I think that the fact that House orders an MRI on just about every patient is acceptable only in the context of the fact that his patients are pre-selected to be complicated.

Though House's diagnostic acumen is flaunted in his inpatient cases, I think his real skill is more evident in general medicine clinic, where he diagnoses patients correctly without imprudently asking for unnecessary tests. This is especially impressive given the fact that House is boarded in 2 subspecialties and somewhat far-removed from primary care. There is a joke in medicine that goes something like this:
An internist, a pathologist, and a family physician go duck hunting. They see an animal that resembles a duck. The internist says, "Let me run some tests to prove that it's not a goose or a rabbit and only then will I proceed to shoot it." The pathologist says, "I'll kill it now and then figure out what it is." The family physician says, "I'm not quite sure what it is, and I don't really care. I have a gun and I'm killing it."
What makes a good diagnostician is the ability to maintain perspective despite maintaining a wide knowledge base. Sometimes, a cough is hereditary angioedema caused by C1 esterase inhibitor deficiency. Other times, a cough is just a cough.

posted by k-deep at 9:48 PM 6 comments


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