What’s Your Differential Diagnosis? Part II

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Suction Unit

Note:  This post is open for discussion and by no means does it mean the thought process discussed here is “the correct” one;  There are many different thought processes that can go through this call, and each different path is valuable.  I found this particular call interesting and worthwhile in sharing.

So given the case study in my last post:  What’s Your Differential Diagnosis?  Part I.  Lets take a look at a possible thought process and what the diagnostic outcome was based on the CT scan done at the hospital (it is recommended you read the first post before reading this post).  

So the call came in as a seizure, but we can’t just assume “it’s just a seizure” so we have to think what causes seizures.  Some of the causes can be epilepsy, stroke/CVA, brain tumor, hypoglycemia, drug use, head trauma, to name a few.  From the history of the bystander, we get the following important clues:

  • Tremors right arm started several weeks ago (new)
  • Never had a seizure before (new)
  • No recent falls
  • Has had previous stroke
  • Medications:  Rabeprazole & plavix

The history of a previous stroke is very important because that puts our patient at a higher risk for a second stroke.  Therefore, the possibility of a CVA (cerebral vascular accident, aka stroke) is high on the list in the differential diagnosis.  However, the fact that the patient was taking plavix makes it rather suspicious since plavix is an anti-platelet medication (more commonly known as a blood thinner).  Why would a doctor prescribe a blood thinner to a patient who has had a CVA?  Well there are two main categories of CVAs:  One caused by hemorrhage or a bleed, and another is thrombotic or caused by a clot.  So most likely his previous CVA was from a clot and was then later prescribed plavix to prevent further strokes.  Obviously this doesn’t rule out a CVA, but the plavix does make me lean away from hemorrhagic CVA instead of towards it.  Why?  Because I’d expect the patient to be much worse condition (instead of just compensated shock) since plavix would cause a serious bleed and its been about 10min since the seizure (although this would depend on the location and size of the bleed, venous vs arterial).  I would also expect to possibly see Cushing’s triad from an increase in ICP (intercranial pressure).  It is also because of plavix, I would presume a thrombotic CVA as unlikely.

Another clue in the history that makes it questionable whether the patient is having a CVA would be the following new onset of symptoms:  Seizure, and right arm tremors.  Sure seizures can result from a stroke and so can the possibility of right arm tremors.  But the patient has been having right arm tremors which started several weeks ago…unless he’s been bleeding into his brain for the past several weeks (plus he’s on plavix, I wouldn’t expect him to be alive at the moment), that just seems unlikely that it could be from a hemorrhagic CVA (even though it doesn’t rule it out).  At this point, suspicion of possibly a brain tumor is pretty high.

The patient also has sudden bouts of vomiting without warning.  Generally if one feels nausea and wants to vomit, you’d be able to have a fore-warning that you’ll vomit.  However, vomiting without warning is an ominous sign of neurological injury, such as the brain.

The neuro exam didn’t provide all the classic signs of a CVA:

  • Equal grip strength
  • No arm drift
  • Patient confused and needs encouragement to respond to commands GCS 13 (4,4,5)
  • Patient can look to the right, but needs encouragement and with difficulty can look to the left, cannot look up or down
  • Patient has slightly droopy smile

However, it’s not often that patients present with textbook signs and symptoms in the field.  The slightly droopy smile could be from the patient’s previous CVA, or a new one.  However, the lack of arm drift and equal grip strength in my opinion further points to a possibility of a brain tumor.  It would also make sense that depending on where the tumor is sitting, it could affect the patient’s gaze but perhaps not his motor skills in his arms.  It is difficult to explain the vital signs though, perhaps it’s the patient’s fear that’s causing that response or (a guess on my part) perhaps the tumor is affecting certain nerves in the nervous system causing shock.  As for the confusion, it could be from the seizure (postictal) he just had or it could very well be something going on in his brain.

Based on the normal temp., infection would go lower on the list of differentials and one can rule out hypoglycemia and epilepsy based on the sugar readings (5.6 mmol/L) and patient history.

Obviously, it’s impossible to come up with a diagnosis without confirmation from a CT scan.  It could well have been a CVA or a brain tumor, but the two would be on the top of the differential diagnosis list.  Based on the overall picture of the call, I would lean towards brain tumor over CVA.  The main clues pulling me in that direction involves the medication plavix, relatively new onset of arm tremors, no previous hx of seizures, and the neurological exam.

(Feel free to respond with your thoughts and comments on this post).


What’s Your Differential Diagnosis Scenario cont’d… 

Several hours later, you learn from the doctor that they did perform a CT scan and had found several tumours in your patient’s brain.  During your call, your patient and bystander had neglected to tell you that the patient has had esophageal cancer, which had obviously now metastasized.

—————————————————————-

CVA—Key Differentiating Signs & Symptoms

Hemorrhagic

Ischemic/Thrombotic

–       Cushing’s triad
–       Severe H/A
–       Pinpoint or =/ unequal pupils
–       Hemiplegia/hemiparesis
–       Facial droop
–       Slurred speech


Signs & Symptoms of Brain Tumor

Of course there are a lot of signs and symptoms of a brain tumor, but below is a short list of the possible signs and the similarities in the call above:

  • Headache progressively worse, severe always in same location

                         + Nausea/vomiting
                         + blurred/double vision

  • Seizures, esp with no history of seizures and older adults
  • Decreased movement/sensation in an arm/leg
  • Hand tremors
  • Weakness, numbness

For more information, you can refer to the following links:

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Comments
6 Responses to “What’s Your Differential Diagnosis? Part II”
  1. K says:

    Cool case! I totally didn’t expect the brain tumors although it was something I considered after CVA or a bleed. You said there’s a few things which take away from the black-and-white textbook presentation of disease and go more into the grey areas of medicine, which I totally agree with and wanted to mention (if you don’t mind!).

    1. Bleeds in the brain will not necessarily cause a stroke. There are four areas you can bleed into the brain: epidural bleeds (above the dura mater), subdural (below), subarachnoid (below the arachnoid membrane), and intracerebral (in the brain tissue itself). Usually it’s only the last two categories that can lead to damage in specific areas of the brain which would lead to a stroke. The other types of bleeds can still manifest with headaches, nausea, vomiting, seizures and neurologic changes as intracranial pressure goes high. Being on plavix does put him at risk of having intracranial bleeds (including hemorrhagic strokes), and not all of them are devastating bleeds that present with unequal pupils, severe headaches, or Cushing’s triad. Some of them may even occur over weeks or months, slowly getting worse over time. Cushing’s triad is something that you usually see in a very critically ill patient whose brain is about to herniate from the pressure being so high, or as some docs say “he’s coning”. And although he is on plavix he is still at high risk of having another thromboembolic stroke, but being on plavix lowers that risk compared to another stroke patient who doesn’t take it.

    2. The classic signs of a CVA are all of what you mentioned, but the whole list usually does not happen together as a constellation unless the patient had a massive global stroke. Posterior circulation strokes can often lead to problems with vision and cranial nerve palsies without causing hemiplegia, facial droop or slurred speech, which are associated with anterior strokes. So just as you said the lack of arm drift or equal grip strength point towards a tumor sitting somewhere else, a stroke can also occur in an area elsewhere that wouldn’t affect these functions.

    3. Just related to the headaches, another important red flag that points towards a brain tumor is if the headaches are worse in the morning when they wake up and then get better through the day.

    4. Good call on the temp lowering the likelihood of a brain abscess, meningitis or other infection. I’m sure you know too that especially in older patients, they may not mount a fever in response to infection, but it still does lower the chances.

    Really good case, I didn’t think it would be a brain tumor. I think the main thing as you mentioned that suggested the tumor was a history of arm tremors that had been going on for awhile which suggests some underlying problem was occuring for much longer than the acute problem.

    • PocketMedic says:

      Hey K! Of course I don’t mind, great information you’ve posted as always, esp on the different bleeds and location specific in terms of symptoms for CVAs.

      Interesting…point number 3, that’s new to me. Any idea why it’d get better throughout the day?

      • K says:

        HEy M!
        Just like with your guy, brain tumors will cause a buildup of pressure in the skull which gives you a bad headache. It’s usually worse in the morning after they’ve been lying flat in bed all night and gravity has caused blood to pool up in the head and make the pressure even higher. Once they get up again that pressure slowly drains off as the blood recirculates.

      • PocketMedic says:

        Lol I thought it might have something to do with blood 😉 Interesting.

  2. grinmedic says:

    Very interesting! Some very clever deductions and information in both the posts and the above comments! Cool case!

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  1. […] free to write your differential diagnosis in the comments section.  What’s Your Differential Diagnosis Part II will reveal what the diagnosis is and the clues to coming to that conclusion based on information […]



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