Diagnosing Parkinson's disease
- [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.