Neurologic Complications of Hematologic Disorders With Drs. Lauren Patrick and Mark Terrelonge

Neurologic complications of hematologic disorders are frequently encountered in clinical practice and can involve both the central and peripheral nervous systems. Early recognition and appropriate management in collaboration with a hematologist are essential to reduce morbidity and mortality.

In this episode, Kait Nevel, MD, speaks with Lauren Patrick, MD, and Mark Terrelonge, MD, MPH, authors of the article “Neurologic Complications of Hematologic Disorders” in the Continuum® February 2026 Neurology of Systemic Disease issue.

Dr. Nevel is a Continuum® Audio interviewer and a neurologist and neuro-oncologist at Indiana University School of Medicine in Indianapolis, Indiana.

Dr. Patrick is an assistant professor of neurology at the University of California, San Francisco, in San Francisco, California.

Dr. Terrelonge is an associate professor of neurology at the University of California, San Francisco, in San Francisco, California.

Additional Resources

Read the article: Neurologic Complications of Hematologic Disorders

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Full episode transcript available here

Dr Nevel: Thick blood, thin blood. These are terms often used by patients and caregivers to describe some of the hematologic disorders that can lead to neurological diseases such as stroke. So, when should we consider a hematologic disorder as a potential cause for neurological conditions, such as stroke or neuropathy. Today I have the opportunity to interview Drs Lauren Patrick and Mark Terrelonge to learn more about neurologic complications of hematologic disorders in their recent article in Continuum.

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 Nevel: Hello, this is Dr Kate Nevel. Today I'm interviewing Drs Lauren Patrick and Mark Terrelonge about their article on neurologic complications of hematologic disorders. This article appears in the February 2026 Continuum issue on neurology of systemic disease. Welcome to the podcast, and please introduce yourself to the audience.

Dr Patrick: Thank you for having us. We're both thrilled to be here. I'm Lauren Patrick, a vascular neurologist and assistant professor at the University of California, San Francisco, and program director for the Vascular Neurology Fellowship here.

Dr Terrelonge: And I'm Mark Terrelonge, I'm an associate professor of neurology and neuromuscular medicine here at UCSF and one of the associate program directors for the adult neurology residency. Nice to meet you.

Dr Nevel: Nice to meet you both. Really looking forward to getting into your article and learning more. So, to kind of kick us off, I always like to ask what do you think is the most important takeaway from your article for the practicing neurologist? And maybe since there are two of you and I suspect you covered slightly different aspects of this article, maybe you could give us two most important takeaways.

Dr Patrick: Sure. I think the biggest takeaway is to keep hematologic disorders on the differential when evaluating patients with neurologic symptoms. Conditions like sickle cell disease, myeloproliferative neoplasms, or plasma cell dyscrasias and paraproteinemia can cause strokes or peripheral neuropathies, and many have specific and targetable treatments. The early recognition and collaboration with our hematology colleagues can truly change patient outcomes, whether that's by initiating cytoreductive therapy, managing thrombocytopenia, or optimizing antithrombotic therapy.

Dr Nevel: Great. So, this is a really big and diverse topic. As always, I'm going to urge our listeners to read the article because there is a lot of really good stuff in your article that we just don't have time to get into during this interview today. But you cover a lot of different hematological disorders and how they can cause neurological complications. One of the major neurological complications of hematological disorders is cerebral vascular events. So, I'm hoping, Warren, that you can walk us through a little bit. When should we consider workup of potential hematologic disorder as a cause when we see a patient with ischemic stroke, because certainly not all patients with ischemic stroke should be getting a broad hematological disorder work up. So how can we kind of identify early on that there might be something else at play?

Dr Patrick: Absolutely, great question. So, in many cases, the underlying hematologic disorder is already known, such as sickle cell disease or polycythemia vera. But sometimes stroke is the initial presentation or manifestation of the disease. So red flags can include young age, recurrent cryptogenic strokes or thrombosis, and unusual locations like the cerebral venous system. Laboratory clues such as unexplained erythrocytosis, thrombocytosis, thrombocytopenia, or hemolytic anemia should raise suspicion for an occult hematologic disorder. In the setting of acute illness, immune-mediated or heparin-induced thrombocytopenia or thrombotic microangiopathies should be suspected in patients that have hemorrhagic and or thrombotic complications, particularly when relevant lab disturbances are present. Acquired thrombophilia such as anti-phospholipid antibody syndrome should be considered in young patients with autoimmune disease, prior venous or arterial thrombotic complications, or pregnancy morbidity. Now, these are rare causes overall, but they're important to catch because the management can differ dramatically from our typical stroke care.

Dr Nevel: Great. And what are some of the most common inherited or acquired thrombophilias and when should we be sending these labs?

Dr Patrick: The hematologic causes really account for small minority of arterial strokes approximately one to two percent, but among those, sickle cell disease, anti-phospholipid antibody syndrome and the myeloproliferative neoplasms are the most common. Timing of testing is key. So, the genetic thrombophilia panels can be drawn at presentation, but lab values such as protein C, protein S, and antithrombin levels may be falsely low during acute thrombosis, so they're often repeated weeks later. Similarly, for anti-phospholipid antibody testing that should be done at presentation and when positive, confirmed at twelve weeks, since transient positivity can occur with affections or acute events. So, in patients that are already anticoagulated for anti-phospholipid antibody syndrome, testing becomes particularly tricky, especially with lupus anticoagulant assays. Some results need to be interpreted carefully or repeated when feasible. The main message is to collaborate early with our hematology colleagues to guide the timing and interpretation of these studies.

Dr Nevel: Yeah, wonderful. Thank you. I'll ask some similar questions about neuropathy. So when should we consider an underlying hematologic disorder as being the cause for someone's neuropathy?

Dr Terrelonge: So, luckily for a neurologist, then serum protein electrophoresis or an SPEP is already a part of the first pass evaluation for even the most common neuropathies we see, technically already considered every time we do an evaluation. However, we do know that most neuropathies progress very slowly and don't really lead to significant limitations in patient activities of daily living. And for those, the initial workup step, you may not need to do any additional search for any hematologic diseases after that first step. Within patients who start to have more unusual features with their neuropathy, including a rapid progression, early proximal weakness, significant and extremely painful neuropathies, significant ataxia, or new tremor or anything that's kind of outside of the garden variety neuropathy, then you should start to think about a hematologic cause. Additionally, if a patient already has a known hematologic malignancy or process before their neuropathy, there should be some form of assessment to see through exam or electrodiagnostically if the two are correlated. I do have to add one caveat, though, and that's just because someone has a hematologic malignancy or a paraprotein seen in their blood, their neuropathy and the neurologic syndrome don't necessarily have to be causally related. So, we have to do some additional testing to determine if the patient's presentation of the paraprotein are actually linked.

Dr Nevel: Can you walk us through a little bit how we determine if they're associated or just coincidental?

Dr Terrelonge: Yeah. So, for some of the proteins, there's a specific phenotype that will come with the specific protein. For example, an anti MAG proteinopathies or MAG standing for a myelin associated glycoprotein, it usually leads to a distal sensor and motor polyneuropathy where the most distal portions of nerves are affected. So, in that case, people might notice that they have numbness and weakness in their toes and their fingers, and it doesn't follow that typical length dependent pattern. So, in that case, if you have the anti mag neuropathy and the electrodiagnostic signature of an anti mag neuropathy along with the symptoms, you're more likely to think that the two are related then if not.

Dr Nevel: Great. Thank you. And I was hoping you could speak a little bit more about amyloidosis just because I think that that's one that can be really tricky to diagnose. And I see patients, you know, have sometimes more drawn out evaluations or see multiple providers before a diagnosis is reached. So, can you speak a little bit more to how we diagnose amyloidosis in relationship to neuropathy or other neurological conditions and when we should push for more invasive testing like a nerve biopsy?

Dr Terrelonge: So, amyloidosis certainly is a tricky diagnosis. I've been tricked by it and I think most of my neuromuscular colleagues have probably been tricked by it at least once. It's a hard diagnosis to make is it usually requires a pretty high index of suspicion, and also requires a tissue diagnosis to cinch. There're some patients who will come in with a prior history of amyloidosis and they're a little bit easier to figure out if the neuropathy is related. Maybe it's started in their heart or their kidney first and then you can just see if the type of amyloid they have usually deposits in nerve, and that may be enough. But if there's any diagnostic uncertainty, you could go forward with tissue biopsy. But it's patients in which the neuropathy is the first symptom that amyloidosis can be especially tricky to diagnose. It's a primarily light chain disease. So, if you do only an SPEP as a part of your initial neuropathy evaluation, you could miss it. But usually, the patients will have either a severely painful neuropathy, early autonomic dysfunction, or really prominent bilateral carpal tunnel syndrome. So, if they have any of those, usually we'll add in an amyloid workup as a part of that of the rest of the workup, which would include both light chain evaluations to see if there's any increase in Lambda or Kappa light chains and then also biopsy. Biopsy can be of the skin or fat pad first, which have reasonable sensitivity for picking up disease, but they're not necessarily a hundred percent. So if the suspicion remains high in those cases, a nerve biopsy should be considered. And the reason why this is important is that the chemotherapeutic agents that we have now can actually help arrest a lot of these diseases and stop further organ involvement. So, if you think about it, it is important to keep pushing and looking until you find it.

Dr Nevel: Thank you so much for that. And a follow up question to that, once patients are started on appropriate therapy, the diagnosis is made, chemotherapy is started, what's the typical clinical course that you see in terms of their neuropathy? Do you ever see improvement or is it arrest of worsening?

Dr Terrelonge: Usually for amyloid, there is an arrest of disease, but in some patients, they could have some improvement, not necessarily a dramatic improvement, but some patients could see some reversal of symptoms. That may not necessarily be because nerves injured nerves are regrowing, but because of reorganization of nerves to muscle, they could have some strength increases or at least less pain.

Dr Nevel: Yeah, thank you. So, when should we involve a hematologist in aiding in the evaluation of patients we suspect may have an underlying hematological disorder? You guys really outlined very nicely in your article some of the laboratory workup or other workup like you just talked about with amyloidosis. But at what point in that workup should we reach out to our hematology colleagues?

Dr Patrick: I would say almost always. So, these disorders are inherently multi-system and benefit from early co-management. In acute sickle cell stroke, for example, hematology helps direct emergent exchange transfusion. For myeloproliferative disorders they guide cyto reduction and long term antithrombotic strategy. And for antibody mediated or plasma cell disorders, hematology determines disease specific therapies. So, neurology may help with identifying the presentation, but the definitive management is almost always shared with our hematology colleagues.

Dr Nevel: And as you both have mentioned that a lot of times in these cases, their hematologic disorder may be already known before they present with their neurological symptoms. So, I imagine obviously in those cases that a hematologist hopefully is already heavily involved in their care. What do you think is the most difficult aspect of identifying and diagnosing patients with neurologic illness as having an underlying hematological disorder?

Dr Patrick: The hardest part is maintaining a high index of suspicion, especially since hematologic causes account for a very small minority of arterial strokes. Most strokes are from traditional vascular risk factors like you mentioned, or cardio embolism, so it's easy to stop diagnostic evaluation after standard studies have been performed. An example of a challenging case is a patient that's young, they've had recurrent cryptogenic stroke, and they could have antiphospholipid antibody syndrome, but it can be easy to miss if their antibody titers are borderline or if they're already anticoagulated, which would complicate retesting. So, it's about balancing the urge to over-test with recognizing the few cases where identifying A hematologic cause truly changes that management.

Dr Terrelonge: And then on the neuropathy side, probably the hardest part is deciding what's causal and what's coincidence. Monoclonal gammopathy of unknown significance, or MGUS, is really common in older adults, so not every M-spike on an SPEP explains a neuropathy. And even sometimes there's times when the neurologic picture will develop a little bit faster than the hematologic one. So, it's hard to put the two together.

Dr Nevel: Yeah. What's the most rewarding aspect of taking care of patients with complications from their hematologic disorders?

Dr Patrick: It's deeply rewarding when a targeted diagnosis leads to a tangible improvement in that patient's care. For example, identifying A cryptogenic stroke is being due to myeloproliferative neoplasm or an inherited thrombophilia allows us to move from empiric treatment to possible disease specific strategy. It’s really gratifying to give patients that clarity, to give them a diagnosis and in some cases prevent future events.

Dr Terrelonge: Agreed. And even on the neuropathy side, almost all of the neuropathies that are hematologically related are treatable. So, it's so satisfying whenever you have a patient with say an anti-MAG neuropathy or Waldenström can start the patient on therapy, and you can see someone who's been having a progressive decline to stability and in those cases sometimes even significant recovery.

Dr Nevel: Yeah, absolutely. Very rewarding when you can identify the problem and make it better. That's what it's all about. So, what are the future areas of research in this area? What do we still need to learn?

Dr Patrick: There's still a lot to learn. I think we need better data on the safety of acute reperfusion therapy and antithrombotic agents, particularly in patients that are at dual risk for bleeding and thrombosis. Other examples, secondary prevention strategies and anti-phospholipid antibody syndrome. What's the best target INR? Do you add aspirin to warfarin or not? All of that is often left up to expert opinion. What's the best management for adults with sickle cell stroke? There are many open questions there. A lot of the protocols that we have in place for sickle cell patients that are adults as derived from pediatric literature and there's vast potential in terms of disease modifying therapies, especially in the fields of sickle cell disease and amyloidosis. And we'll need to reassess how those treatments may change neurologic outcomes.

Dr Terrelonge: I think on the neuropathy side that having some form of new biomarkers to help us clearly know of the neuropathy and that hematologic illness are associated would be very helpful. On the treatment side, a lot of this is really being driven by the hematology space, but new therapies that treat hematologic plasma cell disorders, including some of the new BTK inhibitor, may be incorporated relatively soon into the algorithm for how we treat many of our patients. I'm excited to see what's to come from this.

Dr Nevel: Wonderful. Thank you so much for sharing your knowledge with us today. I know I've certainly learned a lot by reading your article and through our discussion today. Highly encourage our listeners to read your wonderful article, which is a very thorough review of hematologic disorders and neurological complications. Again, today I've been interviewing Dr Lauren Patrick and Dr Mark Terrelonge on their article Neurologic Complications of Hematologic Disorders, which appears in the February 2026 Continuum issue on Neurology of Systemic Disease. Please be sure to check out Continuum Audio episodes from this and other issues. And as always, thank you so much to our listeners for joining today, and thank you so much to Lauren and Mark.

Dr Terrelonge: Yeah, thank you so much for having us.

Dr Patrick: Thank you so much for having us and for highlighting this topic. We hope the issue encourages clinicians to think broadly about hematologic causes of neurologic disease and to continue collaborating closely with our hematology colleagues. It's a complex but very fascinating intersection for both of our fields.

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 this 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.