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Course: Health and medicine > Unit 8
Lesson 10: Parkinson's disease- What is Parkinson's disease?
- What is Parkinson's disease?
- Movement signs and symptoms of Parkinson's disease
- Non-movement symptoms of Parkinson's disease
- The basal ganglia - The direct pathway
- The basal ganglia - Concepts of the indirect pathway
- The basal ganglia - Details of the indirect pathway
- Putting it all together - Pathophysiology of Parkinson's disease
- Genetics and Parkinson's disease
- Diagnosing Parkinson's disease
- Managing Parkinson's disease with medications
- Managing Parkinson's disease with surgery
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Diagnosing Parkinson's disease
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Want to join the conversation?
- As mentioned at2:33, what other than Parkinson's disease can cause parkinsonism?(6 votes)
- Mostly it is caused by medications such as metoclopramide, reserpine. But there are lots of different causes ranging from head injury(including boxing injuries), HIV, Wilson disease to list of toxins such as MPTP, manganese and carbon disulfide.(4 votes)
- Does Parkinson's disease cause any other types of tremors?(2 votes)
Video transcript
- [Voiceover] Here we
have our friend, Vivek. Vivek is a little concerned
because he's having a few problems with his movements lately. For example, he says he's noticed a little bit of a tremor in his hand. And he's also having some problems just kind of moving around, he's having a tough time
walking around like normal, and just doing things around the house, like day-to-day things. This set of symptoms, you know it, sounds like it could be a
few different things, right? But we do notice that Vivek
is about 65 years old now, and we have to, at least
in the back of our minds, consider that maybe this is him presenting with previously undiagnosed
Parkinson's disease. Because the older you are in general, the higher your risk of
developing Parkinson's disease. And some of the things
that he's telling us about, they do sound like they're
early signs of the disease. So what do we wanna do here? How should we try to figure
out if Vivek does, indeed, have Parkinson's disease? Let's take a look at Vivek. Let's ask him some questions,
and do some physical exams on him to try to diagnose
Parkinson's disease. You might've noticed that
I didn't mention anything about any lab tests, any
blood work or brain scans, or anything like that, and
that's because we actually don't have any lab or imaging
tests that actually tell us, "Hey, this is Parkinson's disease." We have a few things
that we can do to rule other things out, but we
don't really have anything that confirms Parkinson's disease. So instead, we're gonna
have to rely on taking a clinical history, and doing
some neurological exams to try to diagnose this possible
Parkinson's disease in Vivek here. So let's go through these together, and let's try to diagnose
Parkinson's disease. Our clinical history, it's
basically like an interview. We wanna ask our patient here a series of questions about the symptoms that are characteristic
of Parkinson's disease. For example, we would definitely
wanna make sure that we ask him about the cardinal signs
of Parkinson's disease. So he might tell us that he's been experiencing a resting tremor. And he might also tell us how
it's been really difficult to initiate movements, to start movements. For example, maybe getting out of a chair seems to be a bit tougher these days. And he also tells us
that he's been feeling like his muscles are just kind of stiff, they're just hard to move. So this does sound an awful lot like the major signs
of Parkinson's disease. The tremor, the bradykinesia,
the rigidity, those things that are actually part of the
symptom complex, Parkinsonism. So it could be Parkinson's
disease, but we do know that there are a few different
diseases and other things that can cause the
syndrome of Parkinsonism, not just Parkinson's
disease, so we need to ask a few more questions
here to try to really get what might be causing
Parkinsonism here in Vivek. Maybe he goes on to
tells us that his tremor actually started in one of his hands, and it's not really
affecting the other hand, at least not yet, so we're thinking, "Okay, this fits even more
with Parkinson's disease." Because remember that the tremor, not always, but often is asymmetric, so just on one side of the body. So the fact that Vivek here
has an asymmetric tremor, it rules out a couple of the
other causes that we know of of Parkinsonism, but it still
keeps Parkinson's disease at the top of our list of differentials, because we know that
in Parkinson's disease, the tremor often starts on
just one side of the body. But we wanna be a bit more
sure about our suspected Parkinson's disease diagnosis here. So we're gonna keep digging a little. What else would be useful
to ask in a history? We might ask Vivek how long he's been having these problems for. We wanna find out, did
they start suddenly? Or have they been developing slowly and worsening over time? If Vivek had just
suddenly woken up one day and started experiencing these problems, we might consider something else other than Parkinson's disease
as the underlying cause. Because remember that Parkinson's disease is a progressive disease, so the signs and the symptoms
develop and worsen over time, rather than coming on suddenly. So we would expect Vivek to
tell us that the problems that he's been having,
the movement problems, have been developing over
time and getting a bit worse. We should also check to
see if Vivek's been having any other problems, because remember that Parkinson's disease
doesn't just cause problems with movements. So maybe we should ask him
about his sense of smell because we know that in
the majority of people with Parkinson's disease,
eventually, they end up having some trouble with, or
lose their sense of smell. So we should ask him about that. We might also ask him
how his mood has been, if he's been feeling
anxious or maybe depressed. Because we know that Parkinson's disease can often cause anxiety and depression. And let's also ask him about
his memory and concentration. Let's ask him how those have been. Has he been feeling forgetful? Maybe he's been having trouble focusing on his everyday tasks, because we know that this can also be a
problem in Parkinson's disease. So the last few things
that we might do here in our history-taking,
is we'll check to see if Vivek has a family history
of Parkinson's disease. Because we know that having
a positive family history for the disease could increase his risk of developing the disease himself. And that's because the cause
could be a genetic cause, a problem with one of the
genes that when mutated, can cause Parkinson's disease. So we'll also check to see if
Vivek is on any medications that would maybe explain
these issues that he's having. Because remember that Parkinson's disease is just one cause of Parkinsonism. And there are some medications out there that we might take for other conditions, that can actually cause Parkinsonism, and we might confuse that
for Parkinson's disease. So some psychiatric drugs out there, and some drugs that we take
that stop us from vomiting. So we'd wanna make sure that
Vivek isn't on any of these that might be causing
Parkinsonism as a side effect. We need to rule this out so
that we don't accidentally think that it's Parkinson's disease. Alright, now we've taken a
pretty good history from Vivek. And we're thinking that
Parkinson's disease might be the cause of his symptoms. So the next thing that we wanna do here, remember that we can't rely
on any blood tests or scans to diagnose Parkinson's disease, so the next thing that we'll
do is a neurological exam, which is just a physical exam. And we're doing it because
we wanna see for ourselves those signs of Parkinsonism that Vivek talked about in his history. A really important part
of a neurological exam when looking for Parkinson's disease, is asking the patient to walk, just to see how they walk and move around. You might remember that
people with this sort of later stages of Parkinson's disease can develop a kind of stooped posture and problems with their balance, and they might start to shuffle
their feet a little bit. Vivek here, if he has Parkinson's disease, it's probably pretty early on, but we just wanna double-check. We still wanna get him to
walk around just to see how his movements are being affected. And we might also try
to bring these symptoms, the bradykinesia and the rigidity, that are so synonymous
with Parkinson's disease. We might try to bring them
out in other ways, too. So maybe we'll get him to stand
up from a sitting position to see how long it takes him. And we might push or pull
on his arms a little bit to see if we can feel that rigidity, which would feel like resistance. And we definitely wanna look
at that tremor, so we wanna see for ourselves if it is,
indeed, a resting tremor. Because remember that there
are lots of different types of tremors, but in Parkinson's disease, we normally see a resting tremor. So we might get Vivek to let
his hand rest on the table, and see if the tremor starts
while it's just resting. Then we might get him
to, maybe, use his hand. Let's get him to grab his keys, and see if the tremor goes away. This would suggest to us, if it did, that it was, indeed, a resting tremor. At this point, we've decided
that Vivek is definitely displaying signs of Parkinsonism, and we think that maybe
it's Parkinson's disease that's causing the Parkinsonism. But we're not 100% sure if Parkinson's disease
is, indeed, the cause. So what could we do if this was the case? One thing that we might do is consider giving Vivek
some of the medication that we would give to someone
with Parkinson's disease. And this medication, what it
does is it's able to restore those levels of dopamine in the brain. Because remember that we lose
a lot of dopamine neurons in Parkinson's disease, and
when we lose dopamine neurons, we lose dopamine, and this
is actually what causes a lot of the movement problems
that we see in the disease. So when we give people with
diagnosed Parkinson's disease these medications, it often really helps with the movement problems
that they're having, by replacing some of that lost dopamine. But on the other hand, if
someone has these signs of Parkinsonism, but Parkinsonism that's not
caused by Parkinson's disease, then the medication
tends to not really help, because the other causes of
Parkinsonism don't really work in the same way that
Parkinson's disease does. It's not necessarily by a
loss of dopamine neurons in the substantia nigra. So just pumping them full
of dopamine won't really do much good in helping with
their movement problems. So this is one way that we might consider to try to figure out if Vivek's
cause of Parkinsonism here is, indeed, Parkinson's disease. Because if his bradykinesia
and his rigidity are improved with dopamine replacement medications, then we might be a
little bit more confident that the underlying cause of his signs is, indeed, Parkinson's disease. The last thing that we might do is get Vivek to come back
after a little bit of time. We might do that so that we can keep track of how Vivek's signs and
symptoms that he's experiencing, how they worsen over time. Because often, it can be
really hard to diagnose Parkinson's disease in the early stages. So we might need to check up on Vivek to see how he progresses,
before we can definitely decide that this is Parkinson's disease.