The Mystery of the Sleepy Sickness
In this episode of Stuff You Should Know, Josh Clark and Chuck Bryant explore encephalitis lethargica (EL), a mysterious neurological illness that emerged in 1916. They examine the condition's three distinct forms, each with unique symptoms ranging from extreme sleepiness to statue-like states, and discuss Dr. Konstantin von Economo's pioneering research during the epidemic that followed.
The hosts delve into decades of scientific investigation into EL's cause and treatment, including neurologist Oliver Sacks' work with L-Dopa in the 1960s, which provided temporary relief for some patients. They also discuss the condition's portrayal in the film "Awakenings" and explain why, despite thousands of research papers, the exact cause of EL remains uncertain, with current theories pointing to a possible autoimmune connection.
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The Nature and Symptoms of Encephalitis Lethargica
Encephalitis lethargica (EL), a mysterious neurological illness that emerged around 1916, initially presented with flu-like symptoms before progressing to more severe neurological issues. Dr. Von Economo identified three main subtypes of the condition: the deadly somnolent-ophthalmoplegic form, characterized by extreme sleepiness and ocular paralysis; the hyperkinetic form, featuring mania and involuntary movements; and the akinetic-amiostatic form, which left patients in statue-like states with unusual "waxy flexibility." Intriguingly, some patients experienced paradoxical kinesia, where they could suddenly perform tasks typically impossible due to their condition.
Historical Efforts to Understand and Treat EL
Dr. Konstantin von Economo led early research efforts into EL, which had reached epidemic proportions by 1919. Despite ruling out various potential causes, including toxins and the Spanish flu, no definitive mechanism was discovered. Chuck Bryant and Josh Clark note that over 9,000 research papers were published during the epidemic, yet questions about transmission and treatment remained unanswered. In the 1960s, neurologist Oliver Sacks achieved temporary "awakenings" in patients using L-Dopa, though these improvements were typically short-lived.
The Relation Between EL and the Movie "Awakenings"
The 1990 film "Awakenings" brought public attention to EL through Robert De Niro's portrayal of Leonard Lowe, a patient trapped in a statue-like state. The film, based on Oliver Sacks' experiences, highlighted the devastating nature of the condition: patients remained conscious but frozen for decades. Chuck Bryant and Josh Clark discuss that since the epidemic, only about 80 suspected cases have been reported, and the condition's exact cause remains uncertain. They note that while L-Dopa continues to be used as a treatment, its effectiveness varies, and some researchers now theorize that EL might be an autoimmune disorder triggered by infection.
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Actionables
- You can raise awareness about rare diseases by sharing intriguing historical medical cases on social media. By posting about encephalitis lethargica and its mysterious history, you contribute to public knowledge and the importance of medical research. For example, create a thread on Twitter detailing the key points of EL's history and its current status, using hashtags like #RareDisease or #MedicalMystery to reach a wider audience.
- Encourage curiosity and critical thinking by starting a book club focused on medical narratives. Select books like "Awakenings" by Oliver Sacks, which delve into the complexities of neurological disorders, and organize monthly discussions to explore the human side of medicine. This can help participants understand the impact of diseases like EL on individuals and society.
- Support ongoing medical research by participating in citizen science projects or fundraising for related causes. Look for platforms that allow non-scientists to contribute to data collection or analysis in medical research, or organize a fundraiser to donate to organizations that fund research into rare neurological disorders. Your involvement can make a difference in the resources available for uncovering the mysteries of conditions like EL.
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The Nature and Symptoms of Encephalitis Lethargica
Encephalitis lethargica is a mysterious neurological illness that arose around 1916, with symptoms overlapping the Spanish flu.
Encephalitis Lethargica: A Mysterious Neurological Illness From 1916
Initial Flu-like Symptoms Lead To Severe Neurological Issues
Initial symptoms of encephalitis lethargica mimicked the flu, which led to the early assumption that it might be an influenza-led infectious encephalitis. However, as Von Economo discovered, this disease would progress beyond flu-like symptoms to more severe neurological issues.
Encephalitis Lethargica Severity and Symptom Subtypes
Von Economo identified different subtypes of encephalitis lethargica, each with its own set of symptoms and outcomes.
Somnolent-Ophthalmoplegic Subtype Was Deadliest, With Over Half Dying
The somnolent-ophthalmoplegic subtype was identified as the most common and deadliest form of the illness. More than half of the patients with this subtype would succumb to the disease. Symptoms included overwhelming sleepiness, ocular paralysis where the eyes do not move, and various neuropsychiatric symptoms such as delirium, confusion, catatonia, and stupor.
Hyperkinetic Subtype: Mania, Involuntary Movements, Disrupted Sleep Patterns
Another form, the hyperkinetic subtype, includes symptoms of mania, involuntary movements, fatigue, weakness, hallucinations, nerve pain in limbs and face, along with disrupted sleep patterns that reverse the day-night cycle.
Akinetic-Amiostatic Subtype Causes Statue-Like Waxy Flexibility
Patients with the akinetic-amio ...
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The Nature and Symptoms of Encephalitis Lethargica
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Clarifications
- Von Economo, in the context of encephalitis lethargica, is a reference to Constantin von Economo, an Austrian psychiatrist and neurologist who played a significant role in identifying and categorizing different subtypes of the illness in the early 20th century. He made important contributions to understanding the symptoms and variations of encephalitis lethargica, including distinguishing between subtypes like somnolent-ophthalmoplegic, hyperkinetic, and akinetic-amiostatic. Von Economo's work helped shed light on the complexities of this mysterious neurological condition.
- The somnolent-ophthalmoplegic subtype of encephalitis lethargica is characterized by overwhelming sleepiness and ocular paralysis, where the eyes are unable to move. Patients with this subtype also experience various neuropsychiatric symptoms such as delirium, confusion, catatonia, and stupor. It is considered the most common and deadliest form of the illness, with over half of the patients succumbing to the disease.
- The hyperkinetic subtype of encephalitis lethargica is characterized by symptoms such as mania, involuntary movements, fatigue, weakness, hallucinations, nerve pain in limbs and face, and disrupted sleep patterns that reverse the day-night cycle. This subtype presents with heightened physical activity, including involuntary movements and restlessness, along with psychological symptoms like hallucinations and mania. Patients may experience a range of symptoms affecting both their physical movements and mental state, leading to a complex clinical presentation. The disrupted sleep patterns and reversal of the day-night cycle can further exacerbate the challenges faced by individuals with this subtype.
- The Akinetic-Amiostatic subtype of encephalitis lethargica is characterized by extreme immobility and a state resembling being frozen in place. Patients with this subtype exhibit a peculiar 'waxy flexibility,' where they can be posed in various positions due to their lack of movement. ...
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Historical Efforts to Understand and Treat EL
The history of Encephalitis Lethargica (EL) showcases various mid-century medical research efforts that sought to uncover the mysteries of the disease that culminated in both hope and tragedy.
20th-Century Medical Research on Encephalitis Lethargica Causes by Dr. Economo
During the early 20th century, Dr. Konstantin von Economo from the University of Vienna's Psychiatric Neurological Clinic grappled with the mystery of EL, a condition that reached epidemic proportions and claimed hundreds of thousands of lives across at least four continents by 1919.
Eliminated Toxins and Infections, but No Definitive Mechanism Found
Economo systematically ruled out neurological toxins, infections, and disorders as causes of EL. He suggested that it was likely transmissible, leading to its naming after him as von Economo encephalitis. Toxic exposure and the hypothesis that the condition was caused by the Spanish flu were both disproven, as the flu's genome did not match the RNA found in the brain tissue of those afflicted by EL.
Chuck Bryant and Josh Clark discuss the unanswered questions surrounding EL: the way it was caught, its contagiousness, and individuals' immunity. Anecdotal cases with contradictory evidence of transmission further complicated the picture, with some households having only one member affected while entire institutions had multiple infections. Despite extensive research, including over 9,000 papers during the epidemic, many questions about transmission, cause, and treatment remained unanswered.
1960s: Oliver Sacks Treated Encephalitis Lethargica At Beth Abraham Hospital
In t ...
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Historical Efforts to Understand and Treat EL
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Actionables
- You can explore the history of medical mysteries by starting a book club focused on non-fiction works that delve into unresolved medical cases. This can foster a deeper understanding of how medical knowledge has evolved and the complexities of diagnosing diseases. For example, you might read "The Family That Couldn't Sleep" by D.T. Max, which explores the strange disease of fatal familial insomnia.
- Enhance your critical thinking skills by analyzing case studies of rare diseases and their treatments. Create a personal journal where you document your thoughts and questions about each case, considering factors like symptoms, treatment responses, and historical context. This exercise can help you appreciate the challenges faced by medical professionals and the importance of ongoing research.
- Volunteer for health awareness campaigns or support groups that fo ...
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The Relation Between EL and the Movie "Awakenings"
Josh Clark and Chuck Bryant explore the depiction of Encephalitis Lethargica (EL) in the film "Awakenings" and discuss its mysterious nature, revealing the real-life challenges faced by patients and the transformative effects of the drug L-DOPA.
1990 Film "Awakenings" Showed Sacks' L-Dopa Treatment For Encephalitis Lethargica Patients
The symptoms of chronic encephalitis lethargica were brought to the public eye in the movie "Awakenings," which was based on neurologist Oliver Sacks' experiences working with patients of the disease in the 1960s. In the film, Robert De Niro plays Leonard Lowe, a patient who was "motionless" and "transfixed in strange postures." This portrayal significantly impacts viewers' understanding of the condition, illustrating patients who are conscious but essentially frozen for decades.
De Niro as a Statue-Like Patient
Leonard Lowe, portrayed by Robert De Niro, is a dramatic representation of the transformative impact L-DOPA can have on patients with encephalitis lethargica. The film showcases how patients, once in a frozen statue-like state, become suddenly aware and capable of interaction after treatment with L-DOPA.
Impact of Condition: Patients Conscious but Frozen for Decades
In the film, there's a heartbreaking depiction of a woman who remains conscious of everything happening around her but is unable to react to events like Pearl Harbor or the assassination of John F. Kennedy because of her encephalitis lethargica. Despite aging to 64 years old, she still feels as if she is only 21 due to being frozen in time.
"Awakenings" Spotlighted the Mystery of Encephalitis Lethargica, With 80 Suspected Cases in 75 Years Post-Epidemic
Chuck Bryant and Josh Clark discuss the rarity and uncertain nature of encephalitis lethargica since the epidemic, noting that its cause and an effective treatment remain elusive. Despite about 80 suspected cases reported over the years, doctors have not yet pinned down an exact definition of the condition or its symptoms.
Uncertain Cause or Effective Treatment For Condition
Chuck Bryant underscores the challenges of EL, indicating that L-DOPA is sometimes used as a treatment, even though it's not consistently effective. He also acknowledges a "silver lin ...
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The Relation Between EL and the Movie "Awakenings"
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Actionables
- You can deepen your empathy by practicing active listening with people who have communication difficulties, such as those with speech impediments or using alternative communication devices. By doing so, you'll become more attuned to the challenges faced by individuals who, like patients with encephalitis lethargica, struggle to express themselves. For example, volunteer at organizations that support people with communication disorders and focus on understanding their needs and responses without preconceptions.
- Enhance your awareness of neurological health by keeping a "brain diary" where you track any unusual symptoms or changes in your cognitive functions. This habit can help you become more conscious of your neurological well-being and prompt early consultation with healthcare professionals if needed. Note down instances of unusual fatigue, memory lapses, or mood swings, and discuss these with your doctor during regular check-ups.
- Cultivate a habit of readi ...
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