Parents’ Guide to Acute Flaccid Myelitis (AFM)
The Center for Disease Control and Prevention has issued a warning about a rapidly growing number of a rare but serious condition known as acute flaccid myelitis (AFM). The CDC announced that 62 cases of the polio-like illness have been confirmed in recent weeks in 22 states. 90% of those affected are 18 years or younger.
AFM is a rare condition that affects the human nervous system, specifically the grey matter in the spinal cord, which causes the reflexes and muscles to become weak or paralyzed. While this condition is not new, the increase in cases starting in 2014 has raised concern and prompted officials to start tracking the disease.
In 2014, the CDC received 120 cases of AFM across the U.S and there have been a total of 386 confirmed cases of the disease since then. However, the CDC estimates that one in a million people in the U.S will get AFM each year. Although specific causes of AFM have not been identified, possible causes include environmental toxins, genetic disorders and viruses.
Symptoms of Acute Flaccid Myelitis
It is extremely important for parents and caregivers to know the symptoms of AFM in order to ensure that their children to get immediate medical care in a timely fashion. Many times acute flaccid myelitis starts with what might look like respiratory illness and fever. Other symptoms include:
- Sudden, acute onset of weakness in the legs or the arms
- Absent or decreased reflexes
- Loss of muscle tone
- Trouble with speech or slurred speech
- Difficulty swallowing
- Difficulty passing urine
- Trouble with eye muscles (difficulty moving the eyes)
- Facial droop
- Drooping of the eyelids
Some people with AFM also report pain in their legs or arms. However, one of the most serious complications of acute flaccid myelitis is respiratory failure due to weakening of the diaphragm and other muscles involved with breathing. In such cases, the patient can end up on a breathing machine (ventilator support). In rare cases, the processes tin the body that trigger AFM can also trigger other neurologic conditions that could even lead to death. It is also important to keep in mind that while most cases of acute flaccid myelitis have been in children (18 years or younger), it can also develop in adults.
If you or your child develops the symptoms of acute flaccid myelitis, you should seek medical attention immediately.
Diagnosis
Acute flaccid myelitis can be hard to diagnose largely because the symptoms are very similar to other neurological conditions, such as transverse myelitis, GBS (Guillain-Barre Syndrome), and ADEM (acute disseminated encephalomyelitis). Diagnosis is based on a combination of physical examination of the patient’s symptoms, an MRI (magnetic resonance imaging) scan of the spinal cord and brain, tests checking nerve speed (NCV, nerve conduction velocity), testing of cerebral spine fluid (CSF, and response of muscles to messages from the nerves (EMG, electromyography). These tests can help doctors distinguish between AFM and other neurological conditions.
Possible Causes of Acute Flaccid Myelitis
AFM typically develops after a viral infection such as West Nile Virus (and other viruses in the same family including Saint Louis encephalitis virus and Japanese encephalitis), adenovirus, and poliovirus. However, in some cases no possible cause is found despite extensive tests. Moreover, even when associated with a viral infection, it’s not clear how the infections trigger AFM, and it’s not known why some people develop the condition after a viral infection and others don’t. Additionally, federal health officials do not know who is at a higher risk of developing acute flaccid myelitis.
Treatment for Acute Flaccid Myelitis
Unfortunately, there’s no treatment for acute flaccid myelitis but neurologists (doctors who specialize in spinal cord and brain illnesses) may suggest certain intervention options usually on a case-by-case basis (depending on the symptoms and severity). For instance, doctors my recommend occupational and/or physical therapy to help with leg and arm weakness caused by the condition. However, long-term outcomes (prognosis) of AFM patients are not clear.
Despite the lack of proven treatment options, early intervention and rehabilitation is always helpful. Some people recover fully most patients continue to experience muscle weakness and the uncertainties may be frustrating.
Researchers and neurologists at Children’s Hospital Los Angeles are developing a new therapeutic nerve transfer surgery that is mainly aimed at helping AFM patients regain movement.
What Can Parents do to Prevent AFM?
West Bile Virus and Poliovirus may sometimes lead to acute flaccid myelitis. Preventive measures include:
- Protecting yourself and your kids from poliovirus by staying up-to date with vaccines especially polio vaccine.
- Protecting against mosquito bites which carry viruses such as West Nile Virus. This can be done by staying indoors at dawn and dusk (when mosquito bites are more common), draining stagnant or standing water near your homes and schools (where mosquitos breed), and using mosquito nets and repellents.
- Washing your hands with soap and water to reduce the risk of infection and avoid spreading germs. Learning about how and when to wash your hands.
Treatment options that have been tried include plasma exchange, antiviral therapy, corticosteroids and immunoglobulin, but there’s no strong evidence that these treatment options affect recovery. Officials have not established a unifying diagnosis and it’s not yet clear what’s really causing the spike in the number of AFM cases.
It’s particularly important for parents to be aware of the symptoms of AFM and seek medical help immediately if they notice sudden onset of muscle weakness or other symptoms of AFM in their children.
