Making the Diagnosis

[pchong]

Quick question for everyone regarding diagnosing patients. I have a difficult time assigning a diagnosis to patients and I may be over thinking it.

So my question is...for any diagnosis out there, are there criteria (clinical or diagnostic) they have to meet. For example, chronic bronchitis has the clinical criteria or fibromyalgia as a diagnosis of exclusion. But what about acid reflux? Asthma? CAD? (One doc I talked to said coronary calcifications are pathognomonic for CAD, doesn't a stress test need to be done?) Is there a book or source that lists the workup for these conditions and if so anyone know where I can find it?

I guess I'm touching on the sensitivity/specificity of all tests. Anyone else have any input?

Your comments are appreciated.

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[MDpride]

I recommend this book:
http://www.amazon.com/Symptom-Diagn...=sr_1_1?ie=UTF8&s=books&qid=1294377270&sr=8-1

Its a very good book that goes stepbystep in making diagnosis from symptoms..

It also talks about sensitivity and specificity of clinical signs and symptoms as well as tests and imaging.


i borrowed it from college lib and loved it. I plan to buy

 

[IMGUSMLEStep1]

Someone recommended this book to me: Problem Oriented Medical Diagnosis
http://www.amazon.com/gp/product/07...=1789&creative=390957&creativeASIN=0781729556

I haven't had a chance to look through it at a library yet so I can't comment on how good it is. I'd love to hear from anyone who has used this book or the other one MDpride mentioned.

 

[pchong]

Just what I was looking for. Will look into the two books, I think MDPride hit it right on the head for what I was looking for. All the best.

 

[KnuxNole]

I have this same problem.

I'm in my first rotation, and the attending yells at me if I get a wrong assessment and plan. The thing is, I am inexperienced, so I can't make up a diagnosis in 5 minutes after seeing a patient that is 100% guaranteed to be right. I dunno how to quickly get better at making diagnosis fast.

 

[jbar]

You could try having a broader diagnosis, like by mechanism or system. So say a patient comes into the ED with chest pain. You can say. my differential is:

1: Inflammatory
2: Neoplastic
3: Infectious
4: Trauma
5: Vascular
6: Psych

Or you can do it by system
1: Cardiac
2: Pulmonary
3: Muscular/skeletal
4: GI/esopehgus

Then within each you figure out a few things that fit that category

1: Cardiac
-AMI
-Endocarditis
-Myocarditis
-CHF

2: Pulmonary
-PE
-Pneumonia
-COPD

etc.

Then you have to know what test or exam or history will rule in or out conditions. This gets back to your initial question. Some things like MI have specific critieria, like positive cardiac enzymes, or certain ECG findings. Others are diganosis of exclusion. But once you have your broad differential you can look up the specific things you are thinking of and see what criteria need to be met. Also as a medical student they don't expect you to nail the diagnosis, but rather to have a good differential and be able to say "I think the chest pain is PE versus MI verses aortic dissection. PE is unlikely because no travel, no smoking etc, MI we need to do an ECG", and so on.

So for my chest pain example:

1: Cardiac
-MI- ECG and enzymes negative.
tive
-CHF- normal EF on echo

2: Pulm
-PE- Chest CTA nega
-Pneumonia- opacity seen on chest x-ray, pt with fever, productive cough. This most likely diagnosis

 

[JustPlainBill]

I have this same problem.

I'm in my first rotation, and the attending yells at me if I get a wrong assessment and plan. The thing is, I am inexperienced, so I can't make up a diagnosis in 5 minutes after seeing a patient that is 100% guaranteed to be right. I dunno how to quickly get better at making diagnosis fast.

First off - get used to getting yelled at....it doesn't stop -- only in residency you get yelled at for everything you do wrong or don't know...not just for not having an A&P---

Second -- the excuse that you're inexperienced -- while valid in most other professions -- isn't valid in medicine as I'm finding out --- you're expected to be functioning at an attending level, no matter what level of training you have...

sorry, but it doesn't get any better.

 

[Instatewaiter]

Quick question for everyone regarding diagnosing patients. I have a difficult time assigning a diagnosis to patients and I may be over thinking it.

So my question is...for any diagnosis out there, are there criteria (clinical or diagnostic) they have to meet. For example, chronic bronchitis has the clinical criteria or fibromyalgia as a diagnosis of exclusion. But what about acid reflux? Asthma? CAD? (One doc I talked to said coronary calcifications are pathognomonic for CAD, doesn't a stress test need to be done?) Is there a book or source that lists the workup for these conditions and if so anyone know where I can find it?

I guess I'm touching on the sensitivity/specificity of all tests. Anyone else have any input?

Your comments are appreciated.

Almost no one does the real diagnostic test for acid reflux. Most people just hear a convincing history and give someone a ppi trial and see if they get better. I guess the board answer is an esophageal pH but rarely done in practice for a diagnosis.

Asthma- reversible obstruction on PFTs. You''ll do PFTs and FEV1/FVC will be <0.8 and will improve markedly with a bronchodilator. Again though, this is not really needed since the history is often self explanatory.

CAD- Cath is probably the gold standard. Stress test is also decent but not as good.

Your knowledge will come with time.

 

[joeDO2]

Almost no one does the real diagnostic test for acid reflux. Most people just hear a convincing history and give someone a ppi trial and see if they get better. I guess the board answer is an esophageal pH but rarely done in practice for a diagnosis.

Asthma- reversible obstruction on PFTs. You''ll do PFTs and FEV1/FVC will be <0.8 and will improve markedly with a bronchodilator. Again though, this is not really needed since the history is often self explanatory.

CAD- Cath is probably the gold standard. Stress test is also decent but not as good.

Your knowledge will come with time.

a pre-hospital trick that we use is to place the pt on a nasal cannula that captures waveform capnography data. if there is a shark fin appearance to the waveform, there is a very good possibility that the culprit is asthma. this test is very quick and easy and can be performed at the bedside. as a side note, you can continuously monitor the patient and assess for changes with your treatments. it will give you a quite accurate respiratory rate and will alert you to any change in their condition.

 

[2012mdc]

Almost no one does the real diagnostic test for acid reflux. Most people just hear a convincing history and give someone a ppi trial and see if they get better. I guess the board answer is an esophageal pH but rarely done in practice for a diagnosis.

Asthma- reversible obstruction on PFTs. You''ll do PFTs and FEV1/FVC will be <0.8 and will improve markedly with a bronchodilator. Again though, this is not really needed since the history is often self explanatory.

CAD- Cath is probably the gold standard. Stress test is also decent but not as good.

Your knowledge will come with time.

Even on UW, the first step is to do PPI. They do tests if the person doesn't respond or has some "alarm" symptoms

 

[OveractiveBrain]

The "formula" for figuring out a clinical diagnosis, even to decide which tests to do, is a fairly complex one. In "Teach on the Wards" by Jeffrey Wiese there is an excerpt from a "teaching script" that explains it. I will summarize.

The History (Cuality, Radiation, Duration, Frequency, yadda, yadda) that characterizes the complaint should focus you in certain directions. The questions you ask everyone wont give you a diagnosis, but will sounds like 3-5 they might be. To clarify, you need to ask focused questions that are unique to the diagnoses you are considering that will increase or decrease your suspicion. Then, do a physical exam with the expressed purpose of increasing or decreasing the probability. Do the same with diagnostic tests.

in Summary: History --> Focused Questions --> Physical Exam --> Diagnostic tests
each --> means readjust probability of one of 3-5 diagnoses based on the classic presentation for these diseases.

-------------------------------------------
Let me give you an example:
A patient comes in with retrosternal burning chest pain that radiates to the jawand has been going on for the past two hours Its the first time its happened.

You think its GERD, or maybe an MI, or maybe an ulcer.

So you ask if the pain is worse with recubency and spicy foods and better with antiacids (GERD), and if the patient has a sensation of bloating, or pain with eating or hours after eating (Ulcers), and if the patient has HTN, DM, Smoking or a family history (MI risk). The patient answers like its GERD

Well now you think its GERD, what tests do we do?

Do a physical exam revealing epigastric tenderness (+ GERD), an EKG showing a normal rhythm with nonelevated cardiac enzymes (r/o MI).

GERD is looking a whole lot better, and the really bad disease is out

Give PPIs.
-------------------------
The problem for students is that they lack the experience (both in textbooks and with real patients) to have developed the background needed to know even the classic presentations of all disease, let alone atypical presentations. If you don't know the disease presentations or risk factors you cant ask the questions. If you cant ask the questions you cant narrow a differential, and you are left with a laundry list of could bes.

Another problem is that students model what they see. The attending or resident (who has read the ER note, the 15 past admission notes, and has heard a report from the student) walks in and asks 4 questions, does one exam manuver, and calls it a day. What the student misses is the complex "summary" that occured in their head. They already know what the diagnosis is likely to be, based on others work, and do not say, out loud, their thought process.

 

[jbar]

You also need to be aware of what service you are on. They are going to expect you to think differently. So in the ED the question is what is going to kill your patient. For chest pain you talk about MI, PE, dissection etc. In an IM out patient visit the question is what is most likely, more angina, muskuloskeletal, GERD. Same goes for speciality clinics. If you are on neuro you can think a patient's falls may due to deconditioning and malnutrition, but you should be talking about neuro related complaints (MS, cerebellar dysfunction, vestibular problems etc)

If you are on the pulmonary service you are getting consulted for your opinion of if the problem is related to the lungs. You have to learn to think like the attending you are with and learn how to rule in or out whatever their bread and butter is.

 

[Acherona]

Medical students don't make diagnoses (except on board exams), they make differentials. There's no way a student can have enough clinical experience to be confident in one diagnosis. Students should come up with a list of plausible things, and have reasons for and against each thing. Tha's what attendings/residents are looking for at your stage.

 

[KnuxNole]

Maybe I'm doing this wrong, but I seem to have trouble choosing the RIGHT things on my differential.

For instance, I came up with 6 possible causes for a certain complaint, and got rejected for every one as soon as I said it. Since I don't know the exact diagnosis 100%, I came up with DD, but for every one I list, the attending cuts me off and said that's wrong, and try again. I feel like I'm doing horrible since if I'm saying wrong differentials, I'm showing that I don't know the diagnosis.

I dunno...I guess I just feel discouraged since I try to make differentials, but if they are wrong, what's the "right" ones to choose? There's only so many you can think of in 5 minutes, but maybe it's more of an experience thing?

"Medical students don't make diagnoses (except on board exams), they make differentials. There's no way a student can have enough clinical experience to be confident in one diagnosis. Students should come up with a list of plausible things, and have reasons for and against each thing. Tha's what attendings/residents are looking for at your stage."

That is a good point, and I probably should have read this before posting >_>

 

[MDpride]

Maybe I'm doing this wrong, but I seem to have trouble choosing the RIGHT things on my differential.

For instance, I came up with 6 possible causes for a certain complaint, and got rejected for every one as soon as I said it. Since I don't know the exact diagnosis 100%, I came up with DD, but for every one I list, the attending cuts me off and said that's wrong, and try again. I feel like I'm doing horrible since if I'm saying wrong differentials, I'm showing that I don't know the diagnosis.

I dunno...I guess I just feel discouraged since I try to make differentials, but if they are wrong, what's the "right" ones to choose? There's only so many you can think of in 5 minutes, but maybe it's more of an experience thing?

"Medical students don't make diagnoses (except on board exams), they make differentials. There's no way a student can have enough clinical experience to be confident in one diagnosis. Students should come up with a list of plausible things, and have reasons for and against each thing. Tha's what attendings/residents are looking for at your stage."

That is a good point, and I probably should have read this before posting >_>

. After ur attending said no to all of ur ddx, did u realize why ur ddx was shot down?

try this book:

http://www.amazon.com/Symptom-Diagn...=sr_1_1?ie=UTF8&s=books&qid=1294377270&sr=8-1

 

[OveractiveBrain]

Maybe I'm doing this wrong, but I seem to have trouble choosing the RIGHT things on my differential.

For instance, I came up with 6 possible causes for a certain complaint, and got rejected for every one as soon as I said it. Since I don't know the exact diagnosis 100%, I came up with DD, but for every one I list, the attending cuts me off and said that's wrong, and try again. I feel like I'm doing horrible since if I'm saying wrong differentials, I'm showing that I don't know the diagnosis.

I dunno...I guess I just feel discouraged since I try to make differentials, but if they are wrong, what's the "right" ones to choose? There's only so many you can think of in 5 minutes, but maybe it's more of an experience thing?

"Medical students don't make diagnoses (except on board exams), they make differentials. There's no way a student can have enough clinical experience to be confident in one diagnosis. Students should come up with a list of plausible things, and have reasons for and against each thing. Tha's what attendings/residents are looking for at your stage."

That is a good point, and I probably should have read this before posting >_>

This is a common problem with many medical students, so Im purposefully bumping this to the first page. One because it comes up alot, and two because MDPride's book suggestion is a good one (albeit a bit complex/thorough). http://www.amazon.com/Symptom-Diagno...4377270&sr=8-1

You can actually use the attending's reaction to gauge their own medical reasoning as well as their teaching quality. The problem with attendings is that they have SO MUCH experience, so much knowledge that they forget what its like to not know how to recognize GERD. Attendings who yell at you, fail to follow any dedicated path, or those who cannot articulate the thought process should be regarded with a grain of salt. While your life may be miserable (and I do hesitate to say this since it may be taken too literally or too far) their comments may be disregarded. You want an attending who can walk you through the process, not the magical House MD who gets the random disease by walking in the room.

Don't feel bad you were failing to get the right answer. Focus on the method and, with patients and experience, you too will "know the answer right away." Of course, physicians who do that actually miss up to 20% of actual diagnoses. But here's the catch: some treatment made them "better" so they must have been "right" (even if they didnt get at the root of the problem), or even worse, when they get it "wrong" they just assume it was "atypical" and "not likely to happen again."

Bottom line: Sorry you are suffering, but DO NOT emulate the person who is making you suffer. They are not as superior as they may seem to be and look towards people more willing to educate you.