A Case of Weakness

Mel presents a case of weakness. Don't read on or you will get the spoiler.

YouTube Link

Eaton-Lambert syndrome presents a unique clinical challenge, especially when linked to underlying malignancies. In this episode, we delve into the connections between muscle weakness, potential cancer diagnoses, and the importance of early recognition in enhancing patient care. 
• Case study of a 60-year-old man with muscle weakness highlights critical symptoms 
• Discussion of differential diagnosis for bulbar muscle weakness 
• Detailed explanation of Eaton-Lambert syndrome and its association with small cell carcinoma 
• Examination of pathophysiology involving autoimmune responses 
• Overview of treatment options focused on addressing underlying conditions 
• Historical context provided about the original researchers, Eaton and Lambert 
• Promotion of "The Pit" show highlighting authentic emergency medicine scenarios

Transcript

Speaker 1: 0:04

Hey, let's do some Invictus stuff. I'm recording this video. I'm going to strip out the audio, put it on the podcast, as always, but if you want the visuals, follow the link in the show notes to get to the YouTube channel. All right, so we are about to do a case. Let's just do this case and then we'll talk about it more in a minute.

Speaker 1: 0:23

So the case is like this it's a 60-year-old man who presents complaining of weakness. So where did the weakness start? It started in my legs, Having difficulty getting out of a chair. Difficulty getting out of a chair suggests proximal muscle weakness. And he also says when he combs his hair it can be difficult but it gets better over time, which is very interesting. So as he exercises it gets better. He's got no significant past medical history no fever, no allergies, no trauma, but he has got recent weight loss and now he's developing difficulty swallowing. That's really what brought him today.

Speaker 1: 0:54

So what do you think the differential diagnosis is here? Well, as we break this down, weakness is really vague and we can go on forever talking about that and we will and it's proximal muscle weakness, but now it's bulbar, and we've been talking about the differential diagnosis of bulbar muscle weakness over the last few weeks. So this is another cause of bulbar muscle weakness. The thing that really stands out is this age, of course, and this recent weight loss which always terrifies me 60 year old person weight weight loss unintentional got to think cancer right. So this is a case of Eaton-Lambert syndrome. Now it's called Lambert-Eaton-Myasthenic syndrome. So this is associated with small cell carcinoma of the lung about 60% of the time. That means that 40% of the time it is not. It can be other cancers or it can happen and we don't know why and there's some genetic predisposition to this. But this is a pretty classic case. This is much less common than myasthenic syndrome. It's like one 50th as common as myasthenia, but it is certainly on exams as a foil all the time.

Speaker 1: 1:59

So it's an autoimmune destruction of the voltage gated calcium channels on the presynaptic side. So you're not able to release acetylcholine. So you get weak, and so therefore the treatments for this is often to treat the underlying cancer. If you can find it, acetylcholine asteroids inhibitors to increase the amount of acetylcholine in that presynaptic space. That's why it probably gets better after exercise is that you're firing, firing, firing and you're getting some acetylcholines in there, which helps with your muscle strength Immune suppression, ivig and a bunch of drugs that I don't really know what they are and you don't need to know either.

Speaker 1: 2:36

But the point is that there are immune suppressing drugs and other drugs which increases presynaptic calcium and does all that stuff that can help these people. But our job is to pick it up. So, classically, it occurs in two peaks around the age of 35, age of 60, classically associated with small cell carcinoma. You develop these antibodies to these calcium channels and I think that's about all we need to know. It causes bulb and muscle weakness. Yes, it tends to actually produce more proximal muscle weakness first, but about 70% of the time it'll end up involving their bulbar muscles.

Speaker 1: 3:12

And who is Eaton and Lambert? Who are these people? Well, it turns out these are neurologists from the Mayo Clinic who described this in the 1950s. So thank you, gentlemen. I don't know who was first or second on the paper I haven't looked it up, but that's probably why this thing keeps flipping its names Eaton-Lambert, lambert-eaton, myasthenic syndrome. All right, now we know.

Speaker 1: 3:31

Now one last thing before we go today Are you watching the Pit on Max? You should be watching the Pit. It is really a great show. We are official collaborators on that show. I'm a consultant on that show. We're trying to make it as accurate as possible to the world of emergency medicine, so you should go watch it and give us your feedback.

Speaker 1: 3:52

Everybody involved really cares about emergency medicine. Noel Wiley really cares about emergency medicine. Joe Sachs, who's the lead medical writer on that show, really cares about emergency medicine. He was on ER. He was on the pit. He's still a practicing ER doc After 30 years. He was on ear. He was on the pit. He's still a practicing er doc after 30 years. He was a couple years ahead of me at ucla great guy doing an amazing job. It's just so fun to be able to be part of that and hopefully there's going to be a season two and if there is, I'm going to have some more things to tell you about it. All right, monkey, you have to watch the show to see the monkey, because he's here with me all the time. Herbert out.