What is Von Economo Encephalitis?
Constantin Alexander von Economo was a psychiatrist and neurologist who first spoke about a condition called encephalitis lethargica to the Vienna Psychiatric Society in 1917. This condition, which causes inflammation in the brain and brainstem, was reported in scattered cases in 1916 and 1917. Between 1919 and 1920, even more cases popped up around the globe. The disease went on to become an epidemic in Europe and North America from 1916 to 1927 and was named von Economo encephalitis in his honor.
Shortly before Economo’s discovery, Jean-Rene Cruchet had been observing military patients in Paris who were showing unusual signs of neuropsychiatric disorders. Encephalitis lethargica, also known as von Economo encephalitis or the sleeping sickness, was initially classified into three types based on symptoms: somnolent-ophthalmoplegic (featuring symptoms like excessive sleepiness or eye muscle paralysis), hyperkinetic (excessively restless), and amyostatic-akinetic (marked by the loss of muscle movement). Currently, it is closely associated with a condition known as postencephalitic parkinsonism.
Von Economo was nominated for the prestigious Nobel Prize in Physiology or Medicine in 1926, 1930, and 1932. Encephalitis lethargica came to be widely known after the English neurologist, Oliver Sacks wrote a book titled “Awakenings.” The story of this disease was further popularized by a movie based on the book that was released in 1990.
What Causes Von Economo Encephalitis?
The exact cause of von Economo encephalitis, a type of brain inflammation, is not entirely known but it might be related to a reaction of our body’s immune system against certain brain proteins. It’s noteworthy that a high number of cases of von Economo encephalitis was observed during the Spanish influenza pandemic, leading some to believe that the flu virus could be the cause. But, recent studies that analyzed old samples of brain tissue have not been able to confirm this link.
Von Economo, who this condition is named after, ruled out factors like food poisoning or gas poison as causes. Since the patients didn’t have close contact with others, he also eliminated common contagious diseases like meningitis and polio as possible causes. Therefore, he suggested that von Economo encephalitis is a distinct illness and not directly caused by a flu infection. However, the possibility of flu being a trigger or precursor to this condition was not entirely dismissed.
In a more recent study in 2001, tissues from patients who had von Economo encephalitis were tested but showed no evidence of the flu virus. Recently, this disease has been associated with a streptococcal infection – a bacterial infection that can cause a range of health problems. The condition falls within a group of pediatric disorders that involve the body’s immune response to streptococcal infections, known as PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections).
Risk Factors and Frequency for Von Economo Encephalitis
The disease is believed to have spread more widely due to the movement of military troops across Europe during World War I. While the exact number of people infected is unknown, it’s estimated that over one million individuals were affected.
- The disease was most common among individuals aged between 10 and 45.
- Both males and females were equally affected.
- The variant known as the somnolent-ophthalmoplegic form had a mortality rate of over 50%.
- Children, older people, and individuals with existing respiratory conditions were especially vulnerable to the disease.
- No major epidemics have been reported since the major outbreak in 1916, but occasional cases still occur.
Signs and Symptoms of Von Economo Encephalitis
Von Economo encephalitis is a disease that has two stages: an initial acute phase and a later chronic phase. The acute phase may begin with symptoms that resemble the flu, but it could lead to severe neurological effects such as partial paralysis and, in some cases, death. Some people may experience a period of mania, uncontrollable movements, vocalizations, eye and jaw muscle rhythms, and muscle twitching. Other variants of the disease can lead to extreme rigidity and loss of movement without apparent weakness. Another version of the disease causes excessive sleepiness, eye muscle paralysis due to the inflammation of the meninges and impairment of certain cranial nerves – nerves that emerge directly from the brain. The issues could include vision problems related to eye movement, and problems linked to facial nerves.
Parkinson-like symptoms, a complication related to the involvement of a part of the brain known as the basal ganglia, can appear either early or late in the disease. Symptoms may include stiffness, slow movement, uncontrollable movements, spasms, and facial tics including the tongue and palate. Von Economo encephalitis can also cause high fever, headache, double vision, dizziness, vomiting, immobility, confusion, and increased muscle stiffness in all limbs. Symptoms that strongly hint at the development of autoimmune encephalitis include excessive sleepiness, easy arousability, eye muscle paralysis, and Parkinson-like signs following a recent respiratory tract infection.
The chronic phase of Von Economo encephalitis may immediately follow the initial phase, but it usually starts between one to five years later. During this phase, Parkinson-like symptoms become prominent. People also experience eye movement abnormalities, sleep disturbances, psychiatric disorders, and involuntary movements. The psychiatric manifestations may consist of mood changes, extreme happiness, heightened sexual drive, and hallucinations. Even after the recovery from eye muscle paralysis and excessive sleepiness, some patients continue to exhibit signs such as increased reflexes and spasms.
Testing for Von Economo Encephalitis
Brain scanning using magnetic resonance imaging (MRI), which is a type of medical imaging technique, may show bright areas or “hyperintense lesions” in specific parts of the brain such as the midbrain tegmentum, thalamus, and basal ganglia. These are regions within the brain responsible for various functions like movement and sensory processing. But don’t worry – these changes normally resolve or go away once recovery from the disease is complete.
Another test can be performed on the cerebrospinal fluid (CSF), which is the clear fluid in your brain and spine. The analysis of this fluid might reveal several things. It could show an increase in protein levels in the fluid. Typically, there will be no bacteria or virus present in the fluid, indicative that an infection isn’t causing the problem. The test may also show the presence of specific proteins called “oligoclonal IgG bands,” as well as a slight increase in the number of lymphocytes, which are a type of white blood cell. The glucose, or sugar level, in the fluid is usually normal.
Lastly, a test called an electroencephalogram (EEG) along with evoked potentials may show slower than normal electrical activity in one or both sides of the brain. Occasionally, there may be focal sharp waves. Evoked potentials tests measure electrical activity in the brain in response to stimulation of sight, sound, or touch. Changes in these could suggest altered brain function. All of these tests and findings help in understanding what’s going on within the brain.
Treatment Options for Von Economo Encephalitis
The treatment for encephalitis, or inflammation of the brain, is generally supportive in nature. A medication known as methylprednisolone can often produce significant improvement when administered in hefty doses via an intravenous drip over the course of three days.
If encephalitis leads to catatonia, a state of unresponsiveness or inability to move, your doctor may recommend a type of medication known as benzodiazepines. Electroconvulsive therapy, or mild electric shocks given to the brain, could be another treatment option.
In cases where these treatments are not effective, other medications may be used. These include bromocriptine, memantine, zolpidem, and valproate. However, the effectiveness of these treatments varies and depends on the individual case.
In encephalitis that causes symptoms similar to Parkinson’s disease, medical professionals have found that dopamine agonists, medications that imitate the action of dopamine (a chemical messenger in the brain), can be effective. Some reports suggest that the simultaneous use of two drugs, levodopa and carbidopa, can offer better results than using levodopa alone.
While some medical professionals recommend the use of immunoglobulin (a type of protein used by the immune system) and plasmapheresis (a procedure that removes, treats, and returns blood plasma to the body), the effectiveness of these treatments remains unclear. Unfortunately, the antiviral medication acyclovir has not shown any proven benefits in these situations.
What else can Von Economo Encephalitis be?
Some conditions that can be confused with Anti-N-methyl-D-aspartate receptor encephalitis include:
- Parkinson’s disease
- Psychiatric illnesses
- Limbic encephalitis
- Herpes simplex encephalitis
- Bickerstaff brainstem encephalitis
- Rasmussen encephalitis
- Hashimoto encephalopathy
These diseases may have similar symptoms, hence, it’s important for doctors to conduct detailed diagnostic tests to distinguish them from Anti-N-methyl-D-aspartate receptor encephalitis.
What to expect with Von Economo Encephalitis
During the acute phase, a third of the patients passed away. Another third managed to recover without any future health problems. However, the remaining third experienced ongoing neurological problems.
Possible Complications When Diagnosed with Von Economo Encephalitis
These are the varied symptoms someone might experience:
- Paralysis on one side of the body
- A state of near-unconsciousness or stupor
- A state of unconsciousness or coma
- Impairment or loss of eye movement
- An intense upward gaze
- Involuntary movements in the body or face
- Involuntary movement on one side of the body
- Difficulties in performing voluntary movements
- Body stiffness, shaking and difficulty with walking, balance, and coordination – symptoms associated with Parkinson’s disease
- Changes in mood
- Physical unresponsiveness, rarely speaking, and maintaining the same posture for long periods
- Inability to speak
- Seeing things that aren’t there (visual hallucinations)
- Periods of extreme excitement or happiness
- Overwhelming happiness
- Problems with feeling excessively sleepy
Preventing Von Economo Encephalitis
Von Economo encephalitis, also known as “sleeping sickness,” is a rare condition that can occur without any known cause. In the past, people who survived this illness often experienced long-lasting effects that affected their nervous system. This means they might have had ongoing issues with movement, sensation, or brain function.
To treat this condition, doctors have typically used a group of medications called dopamine agonists. These medications help to increase the levels of dopamine, a chemical in the brain that helps regulate movement and emotional responses, among other things.
There have been recent studies conducted to investigate whether there’s a link between von Economo encephalitis and the flu virus. However, these studies have found no connection between the two.
