Acute Flaccid Myelitis (AFM) is a rare, yet serious neurological condition affecting the spinal cord, leading to sudden muscle weakness and paralysis, primarily in children. Although AFM shares some symptoms with other neurological diseases, such as polio, it has its unique characteristics and demands special attention. Early detection and treatment are crucial to manage the condition and improve outcomes for those affected.

This article will provide an in-depth exploration of AFM, including its symptoms, causes, treatment options, life expectancy, and the recovery process. We will also touch on how it impacts children and what can be done to ensure early intervention.

What Is Acute Flaccid Myelitis?

Acute Flaccid Myelitis is a rare neurological disorder that affects the grey matter of the spinal cord, leading to a sudden onset of muscle weakness or paralysis. AFM can affect any age group, but the majority of reported cases have been in children. It is an illness that can progress rapidly, making early recognition of symptoms essential for effective treatment.

AFM first gained public attention in 2014 when clusters of cases appeared in the United States. Since then, outbreaks have occurred in multiple countries, typically in the late summer or early fall, and the condition is often linked to viral infections.

AFM presents similarly to polio, as it also targets the spinal cord, but the poliovirus has been ruled out as a cause. Instead, researchers are investigating links to other viruses, environmental factors, and genetic predispositions.

Acute Flaccid Myelitis Symptoms

Recognising the symptoms of AFM is crucial for early intervention. Acute flaccid myelitis symptoms usually begin suddenly and can progress rapidly over the course of a few hours to days. Common symptoms include:

• Sudden weakness in the limbs: The most prominent symptom of AFM is the sudden onset of limb weakness, usually affecting the arms, legs, or both. This weakness is often described as “flaccid,” meaning the muscles become limp and lose normal tone.
• Loss of muscle reflexes: Reflexes, such as those tested with a reflex hammer, may be absent in the affected limbs.
• Difficulty in moving eyes or facial drooping: Some children with AFM experience facial weakness, difficulty in moving their eyes, or drooping eyelids. This can resemble the symptoms of a stroke.
• Problems with swallowing or speaking: In severe cases, the muscles used for swallowing and speaking may be affected, leading to difficulty in eating, drinking, or talking.
• Breathing difficulties: Because AFM can affect the muscles involved in breathing, some patients may require mechanical ventilation. This is a critical complication that necessitates immediate medical intervention.
• Neck or back pain: In some cases, children may complain of pain in the neck or back before the onset of weakness.

These symptoms can vary in severity, with some patients experiencing mild weakness and others developing complete paralysis. The sudden nature of the symptoms means it’s essential to seek medical attention immediately if you notice any signs of muscle weakness, especially in children.

Acute Flaccid Myelitis Causes

The exact acute flaccid myelitis causes are still being investigated, but the condition is thought to be triggered by viral infections. Several viruses have been associated with AFM, including:

• Enteroviruses: Enterovirus D68 (EV-D68) is the most frequently implicated virus in AFM cases. Enteroviruses are common, especially in children, and usually cause mild illnesses, but in some cases, they can lead to severe neurological complications like AFM.
• West Nile Virus: This virus, which is typically spread by mosquitoes, has also been linked to cases of AFM. Though West Nile virus infections are more common in adults, children can be affected as well.
• Adenoviruses: Adenoviruses are another group of viruses that can cause cold-like symptoms but have been found in some AFM patients.
• Other viral infections: Some cases of AFM may be associated with other viruses, such as coxsackievirus and rhinovirus.

Although viral infections seem to be the most common cause, not all cases of AFM are associated with a confirmed viral infection, suggesting that other environmental, genetic, or autoimmune factors may also play a role.

Acute Flaccid Paralysis in Paediatrics

AFM is often discussed in the context of acute flaccid paralysis in paediatrics because children are the most commonly affected group. While acute flaccid paralysis (AFP) is a broader term that includes various conditions resulting in sudden muscle weakness or paralysis, AFM is a specific subset of AFP with distinct features.

Paediatric patients are particularly vulnerable because their immune systems are still developing, and they are more likely to encounter the viral infections associated with AFM. The following factors make the paediatric population more susceptible:

• Weaker immune defences: Children’s immune systems are not as experienced in fighting off infections, making them more vulnerable to the viruses that may trigger AFM.
• Frequent exposure to viruses: Children, especially those in school or daycare settings, are more likely to come into contact with the viruses associated with AFM.
• Developmental concerns: Paralysis or weakness in a growing child can have significant implications for their physical development, mobility, and quality of life.

AFM often progresses quickly in children, and the resulting weakness can be more severe. For this reason, early diagnosis and intervention are critical.

Acute Flaccid Myelitis Treatment

There is currently no specific cure for AFM, and the management of the condition focuses on supportive care and rehabilitation. However, early intervention can significantly improve outcomes. Acute flaccid myelitis treatment involves:

Hospitalisation and Intensive Care

Due to the severity of AFM, especially if breathing muscles are affected, many patients require hospitalisation. Some may need to be placed in an intensive care unit (ICU) to monitor and manage breathing difficulties. If respiratory muscles are involved, mechanical ventilation may be necessary.

Intravenous Immunoglobulin (IVIG)

IVIG is a treatment used to enhance the immune system’s response to infections. It has been used in some AFM cases, although its effectiveness is still being studied.

Plasmapheresis

This procedure filters the blood to remove harmful antibodies. Plasmapheresis has been used in some AFM cases, particularly those suspected to involve an autoimmune component.

Steroids

High doses of steroids, such as corticosteroids, may be used to reduce inflammation in the spinal cord. However, the use of steroids in AFM remains controversial, as they can have mixed effects depending on the cause of the condition.

Antiviral Medications

Since AFM is often associated with viral infections, antiviral drugs may be used, although their effectiveness in treating AFM has not been definitively proven.

Physical and Occupational Therapy

Once the acute phase of the illness has passed, long-term rehabilitation becomes crucial. Physical therapy can help patients regain strength and mobility in affected limbs, while occupational therapy focuses on improving daily functioning. Early and intensive therapy can improve the chances of recovery.

Acute Flaccid Myelitis Recovery

Recovery from AFM can be a long and challenging process. Acute flaccid myelitis recovery varies significantly from patient to patient, depending on the severity of the initial illness, how quickly treatment was administered, and the overall health of the individual. Some children recover fully, while others may be left with lasting weakness or paralysis.

Acute Flaccid Myelitis Life Expectancy

The acute flaccid myelitis life expectancy is generally good, especially when compared to other neurological conditions. Most children who develop AFM do not experience life-threatening complications, provided they receive prompt medical care, especially in cases where respiratory muscles are affected.

However, life expectancy can be impacted in severe cases where breathing difficulties lead to long-term reliance on mechanical ventilation. The overall health and quality of life for those affected can vary widely based on the severity of the illness, the extent of recovery, and the long-term complications.

While AFM itself is not typically fatal, the potential complications, such as respiratory failure, can pose a serious risk. Close monitoring and continued medical care are necessary to manage these risks and ensure a better prognosis.

Importance of Early Diagnosis and Seeking Medical Attention

Early diagnosis of AFM is essential for better outcomes. Since the symptoms can mimic other conditions like Guillain-Barré Syndrome or even polio, healthcare professionals need to conduct a thorough evaluation, which may include:

• MRI of the spinal cord: This can help identify inflammation and damage in the grey matter of the spinal cord.
• Cerebrospinal fluid analysis: A lumbar puncture can reveal elevated white blood cell counts, indicating inflammation or infection.
• Viral testing: Testing for enteroviruses and other potential causes can help guide treatment.

Parents and caregivers should be vigilant for any sudden onset of limb weakness in children, especially during viral outbreaks or seasons when enteroviruses are more common (late summer and early fall). Immediate medical attention is critical to initiating treatment and improving the chances of recovery.

Prevention Strategies for Reducing the Risk of AFM

Prevention strategies for reducing the risk of Acute Flaccid Myelitis (AFM) include:

• Good hand hygiene: Frequent handwashing with soap and water to reduce the spread of viruses.
• Avoid close contact with sick individuals: Minimise exposure to people with viral infections, especially during outbreaks.
• Vaccinations: Stay up-to-date with recommended vaccines, including polio, which can prevent similar illnesses.
• Mosquito protection: Use insect repellents and protective clothing to avoid mosquito-borne viruses like West Nile virus.
• Disinfect surfaces: Regularly clean surfaces that may harbour viruses, especially in shared environments like schools and daycares.
• Maintain a strong immune system: Encourage a healthy diet, regular exercise, and adequate sleep to boost immunity.

A Final Word

Acute Flaccid Myelitis is a serious, life-altering condition that requires immediate attention and care. Recognising the acute flaccid myelitis symptoms early, understanding the acute flaccid myelitis causes, and seeking prompt acute flaccid myelitis treatment can make a significant difference in the outcome. The prognosis and acute flaccid myelitis life expectancy vary widely, but with early diagnosis and aggressive rehabilitation, many patients can regain significant functionality.

Parents, caregivers, and healthcare providers must stay informed about this condition, particularly in children, as they are the most vulnerable. By raising awareness and promoting early intervention, we can improve the chances of recovery and reduce the long-term impact of this debilitating illness.

Sources:

• https://www.mayoclinic.org/diseases-conditions/acute-flaccid-myelitis/symptoms-causes
• https://www.ncbi.nlm.nih.gov/pmc/articles
• https://www.healthline.com/health/acute-flaccid-myelitis
• https://www.mayoclinic.org/diseases-conditions/acute-flaccid-myelitis/diagnosis-treatment
• https://my.clevelandclinic.org/health/diseases/acute-flaccid-myelitis
• https://www.chop.edu/conditions-diseases/acute-flaccid-myelitis-afm
• https://medlineplus.gov/acuteflaccidmyelitis