George - 08 December 2011 09:57 AM

traveler - 08 December 2011 09:48 AM

Me too George - the TB tine test always comes back positive for me and I always have to get an X-ray to prove I don’t have TB. Not sure if it’s from a vaccine though.

Yeah, I don’t know what’s up with that. I know of three (!) of my friends (one from Europe and two from South America) who were put on strong antibiotics for months to cure their TB. All of them were eventually told that it was a mistake and they never had TB.

Why does that happen, macgyver?

The skin test comes up positive because you are essentially testing to see if the person has been exposed to TB. Its not proof of an active infection. You are injecting a small amount of protein under the skin which comes form the TB organism. If the person reacts to it then their immune system has been exposed to the TB organism in some fashion. In the wild this would mean you had TB possibly at some point now or in the past but when a person has been vaccinated their immune system has already been primed to react to this proetien so the test is much less useful if at all.

We generally don’t do a PPD or tine test if we know the person has had the BCG ( TB ) vaccine. We usually screen with a chest xray in those patients if screening is warranted or more recently we have begun using a quantiferon gold test which circumvents this problem

Well, then it’s a mystery. It was a sputum test that I got done and which came back positive. After the x-ray I was told by a TB specialist that I had no TB. My doctor apologized to me and I was given a note (I still have it) saying I had no TB and I was no danger to people around me. I was told that no further tests were required.

Well I’m at a loss. There are only three tests done on sputum for TB. One is a standard gram stain. You can get a result quickly. If its positive its accurate but if its negative its meaningless because most people with TB don’t have enough organism to get a good result.  The gold standard is a traditional sputum culture which can take weeks to get a result on because the organism grows slowly. The third test uses PCR technology and is pretty quick , however none of these tests are effected by a prior BCG vaccine. Only the skin test is affected by the vaccine. Something seems to have gotten lost in translation there.

Well, it’s been over eight years since it had happened, so maybe I am forgetting something.

There is an inherent tension between committing the fallacy of argument by authority and blindly trusting the word of someone just because they have an MD or lots of experience, and making the mistake of imagining that anyone who is reasonably intelligent and has access to the Internet can make complex medical decisions reliably (can we coin a new fallacy here; maybe argumentum ad hubris or argumentum ad internetum? ).

I spend most of my time as an advocate for science-based medicine pointing out how fallible doctors are. And I spend much of my time as a clinician wrestling with wacky, nonsensical theories my clients have deduced on their own or read on the internet. Both are legitimate problems in medicine. Doctors are often wrong, and they are more likely to be wrong in direct proportion to how much they rely on personal experience, mentors, and tradition instead of high-quality scientific research to make decisions. However, lay dilletantes who consult Dr. Google and then decide they know more about the causes and appropriate diagnostic or treatment interventions for their disease than their doctors are, I suspect, more often wrong than their doctors are.

I certainly research medical decisions I must make for myself and my family thoroughly, and I grill my doctors pretty hard about their rationale for their recommendations. However, I also give these recommendations a HUGE amount of weight in making my decisions, especially if they provide a rationale that indicates they have researched and thoughfully examined the issue themselves, rather than simply following an algorithm.

Ultimately, the pendulum has swung from the parternalistic days when doctors were inappropriately revered as all-knowing to the other extreme where everybody believs themselves to be as qualified to make medical decisions as their doctor regardless of what their own particular talent or expertise is. While I agree the patient should ultimately make the decisions when possible, since it is their health and life at stake, I think as patients we need at least as much humilty as we need as doctors about the reliability of our individual judgements.

So I’m not convinced “trust your doctor” is always bad advice, despite the bad advice I’ve seen doctors give. Any relationship with a professional specialist, from auto mechanic to tax accountant to surgeon, involves establishing trust in order to allow someone else to make decisions and take actions that have a potentially significant impact on you. There is some giving up of control needed for this to work. Patients should be informed, should ask probing questions, and ultimately should be able to make their own decisions, but they should bear in mind that they wouldn’t need a doctor at all if that person didn’t have knowledge and skills they don’t.

Well said. I think a lot of this comes down to personality, both the doctor’s and the patient’s. If either one is unwilling to listen to the other then the whole relationship falls apart. I have had vastly different experiences with patients who research their issues before coming to the office. There are those who respect the fact that I have had years of training and decades of experience and am current with the literature. They will present what they have learned on their own and together we will separate the wheat from the chaff. Those interactions usually end well and sometimes i even learn something i didn’t know. At the other extreme are the patients who come in with a chip on their shoulder. Some of these people are just basically disagreeable individuals to begin with, others are frustrated because they have a chronic illness, and many times i find they have visited forums where other disgruntled and misguided people just fan the flames of discontent with stories of misdiagnosis and mistreatment ( the internet is a wonderful thing sometimes isn’t it ). They develop the opinion that doctors don’t know anything and its every man/woman for themselves.

I think Brennan is right though. Its important to educate yourself but google doesn’t make you an MD. There is no replacement for a solid education and years of experience. You wouldn’t attempt to climb Mount Everest on your own after reading about it on the internet. Knowledge is important but an experienced and more knowledgeable guide is the difference between life and death. You need to find a doctor who will listen to you and one you can trust.

My wife is an Ob. Pregnant women can be some of the worst patients when it comes to listening to nonsense they come across on the internet. Most just have reasonable questions about what they have read or heard from friends, however on occasion she will have a patient who gives her a “contract” to sign, and then proceeds to explain that this is a lists all of the things “the internet says I should refuse to let my doctor do”. The patient expects her to sign the agreement saying she wont do these things. Of course she could never ethically or legally do that. Much of whats in the contract would be malpractice and dangerous to the mother or child. In the beginning she would get pretty annoyed, but after so many years she has gotten used to this. Now she calmly hands the contract back to the patient and tells her in no uncertain terms that this relationship isn’t going to work and that she is welcome to go home and let the internet deliver her baby. That usually puts an end to things pretty quickly. The patient either leaves or understands that she has to change her attitude if she wants a healthy baby. Sometimes you have to have a sense of humor in this business.

Sure, Brennen. It all depends on the circumstances. When the doctor gave me antibiotics for what was evidently a fungal infection, I was skeptical (and pissed!). Later on, when I went to see my family doctor who confirmed my suspicion (not diagnosis!; no, I would never do that) that it was indeed a fungal infection, I felt no need to google to see if he decided on the right treatment. I trusted him.