Multiple system atrophy is a rare, sporadic, adult-onset, progressive, and fatal neurodegenerative disease. Accurate and early diagnosis remains challenging because it presents with a variable combination of symptoms across the autonomic, extrapyramidal, cerebellar, and pyramidal systems. Advances in brain imaging, molecular biomarker research, and efforts to develop disease-modifying agents have shown promise to improve diagnosis and treatment.
In this episode, Casey Albin, MD speaks with Tao Xie, MD, PhD, author of the article “Multiple System Atrophy” in the Continuum® August 2025 Movement Disorders issue.
Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia.
Dr. Xie is director of the Movement Disorder Program, chief of the Neurodegenerative Disease Section in the department of neurology at the University of Chicago Medicine in Chicago, Illinois.
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Read the article: Multiple System Atrophy
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Host: @caseyalbin
Full episode transcript available here
Dr. Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast.
Dr Albin: Hello everyone, this is Dr Casey Albin. Today I'm interviewing Dr Tao Xie about his article on diagnosis and management of multiple system atrophy, which appears in the August 2025 Continuum issue on movement disorders. Welcome to the podcast, and please introduce yourself to our audience.
Dr Xie: Thank you so much, Dr Albin. My name is Tao Xie, and sometimes people also call me Tao Z. I'm a mood disorder neurologist, professor of neurology at the University of Chicago. I'm also in charge of the mood disorder program here, and I'm the section chief in the neurodegenerative disease in the Department of Neurology at the University of Chicago Medicine. Thank you for having me, Dr Albin and Dr Okun and the American Academy of Neurology. This is a great honor and pleasure to be involved in this education session.
Dr Albin: We are delighted to have you, and thank you so much for the thoughtful approach to the diagnosis and management. I really want to encourage our listeners to check out this article. You know, one of the things that you emphasize is multiple system atrophy is a fairly rare condition. And I suspect that clinicians and trainees who even have a fair amount of exposure to movement disorders may not have encountered that many cases. And so, I was hoping that you could just start us off and walk us through what defines multiple system atrophy, and then maybe a little bit about how it's different from some of the more commonly encountered movement disorders.
Dr Xie: This is a really good question, Dr Albin. Indeed, MSA---multisystem atrophy----is a rare disease. It is sporadic, adult-onset, progressive, fatal neurodegenerative disease. By the name MSA, multisystem atrophy. Clinically, it will present with multiple symptoms and signs involving multiple systems, including symptoms of autonomic dysfunction and symptoms of parkinsonism, which is polyresponsive to the levodopa treatment; and the symptom of cerebellar ataxia, and symptom of spasticity and other motor and nonmotor symptoms. And you may be wondering, what is the cause- underlying cause of these symptoms? Anatomically, we can find the area in the basal ganglia striatonigral system, particularly in the putamen and also in the cerebellar pontine inferior, all of the nuclear area and the specific area involved in the autonomic system in the brain stem and spinal cord: all become smaller. We call it atrophy. Because of the atrophy in this area, they are responsible for the symptom of parkinsonism if it is involved in the putamen and the cerebral ataxia, if it's involved in the pons and cerebral peduncle and the cerebellum. And all other area, if it's involved in the autonomic system can cause autonomic symptoms as well.
So that's why we call it multisystem atrophy. And then what's the underlying cellular and subcellular pathological, a hallmark that is in fact caused by misfolded alpha-synuclein aggregate in the oligodontia site known as GCI---glial cytoplasmic increasing bodies---in the cells, and sometimes it can also be found in the neuronal cell as well in those areas, as mentioned, which causes the symptom. But clinically, the patient may not present all the symptoms at the same time. So, based on the predominant clinical symptom, if it's mainly levodopa, polyresponsive parkinsonism, then we call it MSAP. If it's mainly cerebellar ataxia, then we call it MSAC. But whether we call it MSP or MSC, they all got to have autonomic dysfunction. And also as the disease progresses, they can also present both phenotypes together. We call that mixed cerebellar ataxia and parkinsonism in the advanced stage of the disease. So, it is really a complicated disease. The complexity and the similarity to other mood disorders, including parkinsonism and the cerebellar ataxia, make it really difficult sometimes, particularly at the early stages of disease, to differentiate one from the other. So, that was challenging not only for other professionals, general neurologists and even for some movement disorder specialists, that could be difficult particularly if you aim to make an accurate and early diagnosis.
Dr Albin: Absolutely. That is such a wealth of knowledge here. And I'm going to distill it just a little bit just to make sure that I understand this right. There is alpha-synuclein depositions, and it's really more widespread than one would see maybe in just Parkinson's disease. And with this, you are having patients present with maybe one of two subtypes of their clinical manifestations, either with a Parkinson's-predominant movement disorder pattern or a cerebellar ataxia type movement disorder pattern. Or maybe even mixed, which really, you know, we have to make things quite complicated, but they are all unified and having this shared importance of autonomic features to the diagnosis. Have I got that all sort of correct?
Dr Xie: Correct. You really summarize well.
Dr Albin: Fantastic. I mean, this is quite a complicated disease. I would pose to you sort of a case, and I imagine this is quite common to what you see in your clinic. And let's say, you know, a seventy-year-old woman comes to your clinic because she has had rigidity and poor balance. And she's had several falls already, almost always from ground level. And her family tells you she's quite woozy whenever she gets up from the chair and she tends to kind of fall over. But they noticed that she's been stiff,and they've actually brought her to their primary care doctor and he thought that she had Parkinson's disease. So, she started levodopa, but they're coming to you because they think that she probably needs a higher dose. It's just not working out very well for her. So how would you sort of take that history and sort of comb through some of the features that might make you more concerned that the patient actually has undiagnosed multiple systems atrophy?
Dr Xie: This is a great case, because we oftentimes can encounter similar cases like this in the clinic. First of all, based on the history you described, it sounds like an atypical parkinsonism based on the slowness, rigidity, stiffness; and particularly the early onset of falls, which is very unusual for typical Parkinson disease. It occurs too early. If its loss of balance, postural instability, and fall occurred within three years of disease onset---usually the motor symptom onset---then it raises a red flag to suspect this must be some atypical Parkinson disorders, including multiple system atrophy. Particularly, pou also mentioned that the patient is poorly responsive to their levodopa therapy, which is very unusual because for Parkinson disease, idiopathic Parkinson disease, we typically expect patients would have a great response to the levodopa, particularly in the first 5 to 7 years. So to put it all together, this could be atypical parkinsonism, and I could not rule out the possibility of MSA. Then I need to check more about other symptoms including autonomic dysfunction, such as orthostatic hypertension, which is a blood pressure drop when the patient stands up from a lying-down position, or other autonomic dysfunctions such as urinary incontinence or severe urinary retention. So, in the meantime, I also have to put the other atypical Parkinson disorder on the differential diagnosis, such as PSP---progressive supranuclear palsy---and the DLBD---dementia with Lewy body disease.---Bear this in mind. So, I want to get more history and more thorough bedside assessment to rule in or rule out my diagnosis and differential diagnosis.
Dr Albin: That's super helpful. So, looking for early falls, the prominence of autonomic dysfunction, and then that poor levodopa responsiveness while continuing to sort of keep a very broad differential diagnosis?
Dr Xie: Correct.
Dr Albin: One of the things that I just have to ask, because I so taken by this, is that you say in the article that some of these patients actually have preservation of smell. In medical school, we always learn that our Parkinson's disease patients kind of had that early loss of smell. Do you find that to be clinically relevant? Is that- does that anecdotally help?
Dr Xie: This is a very interesting point because we know that the loss of smelling function is a risk effect, a prodromal effect, for the future development of Parkinson disease. But it is not the case for MSA. Strange enough, based on the literature and the studies, it is not common for the patient with MSA to present with anosmia. Some of the patients may have mild to moderate hyposmia, but not to the degree of anosmia. So, this is why even in the more recent diagnosis criteria, the MDS criteria published 2022, it even put the presence of anosmia in the exclusion criteria. So, highlight the importance of the smell function, which is well-preserved for the majority in MSA, into that category. So, this is a really interesting point and very important for us, particularly clinicians, to know the difference in the hyposmia, anosmia between the- we call it the PD, and the dementia Lewy bodies versus MSA.
Dr Albin: Fascinating. And just such a cool little tidbit to take with us. So, the family, you know, you're talking to them and they say, oh yes, she has had several fainting episodes and we keep taking her to the primary care doctor because she's had urinary incontinence, and they thought maybe she had urinary tract infections. We've been dealing with that. And you're sort of thinking, hm, this is all kind of coming together, but I imagine it is still quite difficult to make this diagnosis based on history and physical alone. Walk our listeners through sort of how you're using MRI and DAT scan and maybe even some other biomarkers to help sort of solidify that diagnosis.
Dr Xie: Yeah, that's a wonderful question. Yeah. First of all, UTI is very common for patients with MSA because of urinary retention, which puts them into a high risk of developing frequent UTI. That, for some patients, could be the very initial presentation of symptoms. In this case, if we check, we say UTI is not present or UTI is present but we treat it, then we check the blood pressure and we do find also hypertension---according to new diagnosis criteria, starting drop is 20mm mercury, but that's- the blood pressure drop is ten within three minutes. And also, in the meantime the patients present persistent urinary incontinence even after UTI was treated. And then the suspicion for MS is really high right at this point. But if you want increased certainty and a comfortable level on your diagnosis, then we also need to look at the brain MRI mark. This is a required according to the most recent MDS diagnosis criteria. The presence of the MRI marker typical for MSA is needed for the diagnosis of clinically established MSA, which holds the highest specificity in the clinical diagnosis. So then, we have- we’re back to your question. We do need to look at the brain MRI to see whether evidence suggestive of atrophy around the putamen area, around the cerebellar pontine inferior olive area, is present or not.
Dr Albin: Absolutely. That's super helpful. And I think clinicians will really take that to sort of helping to build a case and maybe recognizing some of this atypical Parkinson's disease as a different disease entity. Are there any other biomarkers in the pipeline that you're excited about that may give us even more clarity on this diagnosis?
Dr Xie: Oh, yeah. This is a very exciting area. In terms of biomarker for the brain imaging, particularly brain MRI, in fact, today there's a landmark paper just published in the Java Neurology using AI, artificial intelligence or machine learning aid, diagnoses a patient with parkinsonism including Parkinson's disease, MSA, and PSP, with very high diagnostic accuracy ranging from 96% to 98%. And some of the cases even were standard for autopsy, with pathological verification at a very high accurate rate of 93.9%. This is quite amazing and can really open new diagnosis tools for us to diagnose this difficult disease; not only in an area with a bunch of mood disorder experts, but also in the rural area, in the area really in need of mood disorder experts. They can provide tremendous help to provide accurate, early diagnosis.
Dr Albin: That's fantastic and I love that, increasing the access to this accurate diagnosis. What can't artificial intelligence do for us? That's just incredible.
Dr Xie: And also, you know, this is just one example of how the brain biomarker can help us. Theres other---a fluid biomarker, molecular diagnostic tools, is also available. Just to give you an example, one thing we know over the past couple years is skin biopsy. Through the immunofluorescent reaction, we can detect whether the hallmark of abnormally folded, misfolded, and the phosphorate, the alpha-synuclein aggregate can be found just by this little pinch of skin biopsy. Even more advanced, there's another diagnosis tool we call the SAA, we call the seizure amplification assay, that can even help us to differentiate MSA from other alpha-synucleinopathy, including Parkinson disease and dementia with Lewy bodies. If we get a little sample from CSF, spinal cerebral fluids, even though this is probably still at the early stage, a lot of developments still ongoing, but this, this really shows you how exciting this area is now. We’re really in a fast forward-moving path now.
Dr Albin: It's really incredible. So, lots coming down the track in, sort of, MRI, but also with CSF diagnosis and skin biopsies. Really hoping that we can hone in some of those tools as they become more and more validated to make this diagnosis. Is that right?
Dr Xie: Correct.
Dr Albin: Amazing. We can talk all day about how you manage these in the clinic, and I really am going to direct our listeners to go and read your fantastic article, because you do such an elegant job talking about how this takes place in a multidisciplinary setting, if at all possible. But as a neurointensivist, I was telling you, we have so much trouble in the hospital. We have A-lines, and we have the ability to get rapid KUBs to look at Ilias, and we can have many people as lots of diagnosis, and we still have a lot of trouble treating autonomiclike symptoms. Really, really difficult. And so, I just wanted to kind of pick your brain, and I'll start with just the one of orthostatic hypotension. What are some of the tips that you have for, you know, clinicians that are dealing with this? Because I imagine that this is quite difficult to do without patients.
Dr Xie: Exactly. This is indeed a very difficult symptom to deal with, particularly at an outpatient setting. But nowadays with the availability of more medication---to give an example, to treat patients with orthostatic hypertension, we have not only midodrine for the cortisol, we also have droxidopa and several others as well. And so, we have more tools at hand to treat the patient with orthostatic hypertension. But I think the key thing here, particularly for us to the patient at the outpatient setting: we need to educate the patient’s family well about the natural history of the disease course. And we also need to tell them what's the indication and the potential side effect profile of any medication we prescribe to them so that they can understand what to expect and what to watch for. And in the meantime, we also need to keep really effective and timely communication channels, make sure that the treating physician and our team can be reached at any time when the patient and family need us so that we can be closely monitoring, their response, and also monitoring potential side effects as well to keep up the quality of care in that way.
Dr Albin: Yeah, I imagine that that open communication plays a huge role in just making sure that patients are adapting to their symptoms, understanding that they can reach out if they have refractory symptoms, and that- I imagine this takes a lot of fine tuning over time.
Dr Xie: Correct.
Dr Albin: Well, this has just been such a delight to get to talk to you. I really feel like we could dive even deeper, but I know for the sake of time we have to kind of close out. Are there any final points that you wanted to share with our listeners before we end the interview?
Dr Xie: I think for the patients, I want them to know that nowadays with advances in science and technology, particularly given a sample of rapid development in the diagnostic tools and the multidisciplinary and multisystemic approach to treatment, nowadays we can make an early and accurate diagnosis of the MSA, and also, we can provide better treatment. Even though so far it is still symptomatically, mainly, but in the near future we hope we can also discover disease-modifying treatment which can slow down, even pause or prevent the disease from happening. And for the treating physician and care team professionals, I just want them to know that you can make a difference and greatly help the patient and the family through your dedicated care and also through your active learning and innovative research. You can make a difference.
Dr Albin: That's amazing and lots of hope for these patients. Right now, you can provide really great care to take care of them, make an early and accurate diagnosis; but on the horizon, there are really several things that are going to move the field forward, which is just so exciting. Again today, I've been really greatly honored and privileged to be able to talk to Dr Tao Xie about his article on diagnosis and management of multiple system atrophy, which appears in the August 2025 Continuum issue on movement disorders. Be sure to check out Continuum Audio episodes for this and other issues. And thank you again to our listeners for joining us today.
Dr Xie: Thank you so much for having me.
Dr Monteith: This is Dr Teshamae Monteith, Associate Editor of Continuum Audio. If you've enjoyed this episode, you'll love the journal, which is full of in-depth and clinically relevant information important for neurology practitioners. Use the link in the episode notes to learn more and subscribe. AAN members, you can get CME for listening to this interview by completing the evaluation at continpub.com/audioCME. Thank you for listening to Continuum Audio.