Chronic Focal Encephalitis (Rasmussen's Encephalitis): Causes, Symptoms, Complications, And Treatment

Chronic Focal Encephalitis (Rasmussen's Encephalitis) or Rasmussen syndrome can be described as a rare disorder that causes encephalitis (chronic progressive inflammation) mainly into the cerebral hemisphere of the central nervous system. Due to the uncontrollable progressive inflammation, the neurons present in the inflated area experience frequent episodes of uncontrolled electrical disturbances leading to progressive cerebral destruction and epileptic seizures (epilepsy).

Prolonged cerebral destruction eventually weakens the part of the brain causing hemiparesis, language problems, and intellectual disabilities associated with the same part.

The root cause of chronic and prolonged inflammation is still under the shade, yet two hypotheses might be acting as a trigger. The first one is the reaction of a foreign antigen (infection) like childhood infections, influenza, measles, cytomegalovirus, or insect bite virals. On the other hand, the cause can be an autoimmune disease ( a medical condition where an individual’s immune system attacks the healthy human cells) which can be limited to one side of the brain.

In most cases, the symptoms start to appear at the early stages of life which may escalate within the first 8 to 12 months of life. But the chronic inflammation doesn't need to only trigger in the infancy stage, they can have children at ages two and ten years. When the inflammation reaches its maximum point, the patient has permanent neurological deficits followed by a slow speed of swelling.

One of the most common signs of Rasmussen's Encephalitis is the visible inflammation in the cerebral hemisphere of the central nervous system. Apart from that here are some initial signs that your child may show at the early stages of inflammation.

In case the inflammation is caused by foreign antigen the child may develop mild flu-like symptoms like:

• Headache
• Aches in muscles or joints
• Nausea and vomiting
• Body stiffness
• Fatigue or weakness
• Fever
• Bulging in the soft spots (fontanels) of an infant's skull
• Poor feeding or not waking for a feeding
• Irritability

Other severe symptoms may include:

• Problems with speech or hearing
• Seizures
• Confusion, agitation, or hallucinations
• Muscle weakness
• Loss of sensation or paralysis in certain areas of the face or body
• Loss of consciousness (including coma)

In case the inflammation has been caused by autoimmune diseases the symptoms may include:

• Fatigue
• Achy muscles
• Skin rashes
• Trouble concentrating
• Swelling and redness
• Low-grade fever
• Numbness and tingling in the hands and feet
• Hair loss

Further complications that are common in both cases may include:

• Epilepsia partialis continua (EPC) - prolong and progressive and near-continuous focal seizures.
• Developmental arrest - in the case of Rasmussen's Encephalitis, It can make it hard for the paint to gain control of its psychosocial behavioral process during its critical period which results in a developmental failure like physical and mental abilities at early stages of life.
• Developmental regression - loss of previously acquired physical and mental abilities.
• Atrophy - Degeneration of one side of the brain.
• Myoclonus - Continuous series of the rapid, rhythmic succession of contractions and relaxations of a muscle or muscle group of the arms, legs, and face. Depending upon the severity of the case the contractions can be singularly or repetitive in their nature of the occurrence.
• Hemiparesis - Progressive paralysis of one side of the body opposite to the side of inflammation in the brain.
• Progressive confusion.
• Disorientation.
• Dementia - Deterioration of intellectual abilities.

Since Chronic Focal Encephalitis (Rasmussen's Encephalitis) is mostly seen in children who are ten years of age and younger, it is rare for the patient to survive to the stage of adolescents and young adults. The calculation is an average of every case of Chronic Focal Encephalitis (Rasmussen's Encephalitis) regardless of its root cause, it has been estimated as 2.4/10,000,000 persons less than or equal to 18 years of age in the overall population of the world.

The prognosis for the life expectancy in the case of Rasmussen’s encephalitis varies based on the cause and the treatment that has been designed to treat the specific disease. Even though the current medical facilities around the globe are quite advanced in their medical approach and develop a variety of medical treatments, there may be a 50% chance that it may not show any signs of recovery.

Furthermore, the medical condition does not stop the physical damage of the brain, it also causes mental impairments like seizures, paralysis, cognitive deficits, and problems with speech on the opposite brain hemisphere, which makes it hard for the patient to survive.

Most of the rare medical illnesses are hard to detect, especially where there are some other disorders and diseases present already with identical sets of symptoms. The confusion not only hinders the treatment process but also delays it which makes it a serious issue. So here are some of the following disorders that may be similar to Chronic Focal Encephalitis (Rasmussen's Encephalitis):

• Focal cortical dysplasia: Can be described as a congenital abnormality that can be characterized by bizarre appearing neurons and abnormal organization of the layers of the brain. Depending upon the type, the trigger can be either genetic or acquired factors developed by cortical dysplasia. Symptoms like inflammation, epilepsy, and seizures are due to the lesions of a high propensity which does not show any recovery signs when used in the current medical approach. Identical to Rasmussen's Encephalitis the condition also starts to develop in children at 2 to 4 years. One can identify the difference through the medical diagnosis of the brain as Chronic Focal Encephalitis does not involve any unusual neurons and brain structure.
• Alpers-Huttenlocher syndrome: Can be described as a rare genetic disease in children suffering from neurologic and hepatic symptoms. The neurological group of symptoms involves muscle-, nerve-, and brain-related functions like intractable epilepsy ( seizures that do not improve with treatment) and psychomotor regression ( loss of mental and movement abilities). The age group that AHS targets are the same as ER which is children between ages 2 and 4. What makes it distinctive from Rasmussen's Encephalitis is that AHS is caused by abnormal mutations in the gene called POLG1.

Diagnosis of Chronic Focal Encephalitis (Rasmussen's Encephalitis) will be initiated by collecting data via clinical evaluation, physical examination, and testing. Your medical advisor will ask your questions associated with the discomforts the patient feels, abnormal physiological and psychological signs and duration of the symptoms like seizures, etc. the case will be further proceeded by a complete neurological evaluation including advanced techniques such as:

• EEG: Electroencephalogram is a test usually conducted to get an analysis of brain activity or in the case of Rasmussen's Encephalitis analysis of the brain's electrical impulses. The test is conducted with the help of small sensors which are attached to the scalp to collect data of the electrical signals produced by the brain when brain cells send messages to each other. These signals are recorded by the medicine so that your doctor can study the brain wave patterns that act as triggers for certain types of epilepsy.
• MRI: Magnetic resonance imaging is a radiological imaging technique that creates images of the anatomy and the physiological processes of the body. In the case of Rasmussen's Encephalitis the radio waves, magnetic field gradients, and magnetic fields are used to create cross-sectional detailed images of the brain. MRI is one of the most effective ways to detect medical conditions like RE as in most cases two scans would be sufficient enough to detect the detailed progressive shrinkage of the affected side of the brain.

Apart from that, new research has now suspected that Chronic Focal Encephalitis (Rasmussen's Encephalitis) is a more triggered autoimmune disorder that can be diagnosed via histopathologic review of the tissue which involves examining tissues and/or cells under a microscope.

Autoimmune disease is a condition where an individual immune system attacks its own body by creating destruction in the healthy cells and tissues. Depending upon the default antibodies the immune system will attack different organs. Scientists are still looking for the antibodies that are responsible for Rasmussen's Encephalitis or cause inflammation in the brain and spinal cord causing neurological or psychiatric abnormalities.

Generally, disorders like these are present in the child's immune system from fetal age and start to show their symptoms from birth to the age of 2. Even though the autoimmune disease is a genetic disorder that can be either recessive or dominant in the nature of the mutation, it needs an external factor to get it triggered. This means children who are affected by immunity disorders mostly get it from one or both parents who are carriers of the disease but never get affected by any disease which may trigger the immune system to act against your body.

As mentioned earlier, the root cause or the triggering agent that is responsible for all kinds of autoimmune diseases is still unknown, yet scientists know that there may be a variety of causes behind it because there is some testing available that has successfully detected some medical conditions.

It has been seen that women during pregnancy or post-pregnancy are more prone to get triggered by immunity disorders than men, this is because of the hormonal fluctuation that a woman faces during pregnancy. In the case of immunity disorders that trigger brain inflammation, it is only seen in children not in their parents as the pathogen is only found in fetuses and children.

Children affected by brain inflammation not only show physical disorders limited to the nervous system, but they may also show problems like vision loss, weakness of arms or legs, loss of language, and sleep problems, severe depression and hallucinations, as well as paranoid, obsessive, or erratic behavior.

Treatment of Chronic Focal Encephalitis (Rasmussen's Encephalitis) is threefold which includes physical therapy, and medical therapies, and mental support for both patient and their family.

The first step is to collect the medical history of the patient and their family to analyze the symptoms, specifically brain inflammation. After the medical diagnosis, your medical professional will designate a specific treatment. Medication including steroids, immunoglobulin, and tacrolimus, for instance, anti-seizure medications like anticonvulsants may be prescribed to treat seizures.

The medical procedure will also include surgery called cerebral hemispherectomy which involves disconnection or partial/full removal of half of the brain is the only way known by the medical professionals to cure seizures and halt neurodevelopmental regression. However, this surgery has side effects like weakness of one side of the brain (hemiparesis), impairment of vision to one side (hemifield defect), abnormal speech and language.

Physiological therapy like Immunological therapies will be recommended to slow down the neurological and structural deterioration. The precise role of immunological therapies like tacrolimus, intravenous immunoglobulins, etc. is to manage the Chronic Focal Encephalitis (Rasmussen's Encephalitis) but not epilepsy or progressive brain atrophy and other symptoms which remain to be determined.

The psychological aspect of the treatment is mostly symptomatic and supportive, which mainly focuses on the psychological development of the patient. Special learning training for learning and maintaining social skills. Not only the patient but also for the family to help them cope with the stress associated with the medical treatment.

Summary: Rasmussen syndrome can be described as a rare disorder that causes chronic progressive inflammation mainly into the cerebral hemisphere of the central nervous system. The root cause of chronic and prolonged inflammation is still unknown.