Jamie-Lynn Sigler says son was hospitalized for 33 days with autoimmune condition

Sigler said her son Beau was believed to have a condition called ADEM.

Actress Jamie-Lynn Sigler is sharing details of her son's recovery from an autoimmune condition that left him hospitalized for over 30 days.

On Friday, Sigler, a mom of two sons, shared on Instagram that her eldest son Beau, who will turn 11 on Aug. 28, was discharged from a children's hospital in Austin, Texas, after 33 days.

The accompanying video shows Beau dancing down the hallway of the hospital and giving high-fives to staff members gathered to cheer him on.

In an earlier post on Aug. 6, Sigler said that Beau was thought to have acute disseminated encephalomyelitis, or ADEM, an autoimmune reaction that affects the brain and the spinal cord, according to the National Institute of Neurological Disorders and Strokes.

"To say this has been hard, is an understatement, and I've never felt more broken," the "Sopranos" star captioned a photo of herself with Beau at the time, adding, "But, I have also never felt more love. The way our friends and family have come to our rescue during this terrible time has been one of the most incredible things to experience."

Sigler, also the co-host of the podcast "MeSsy" with actress Christina Applegate, wrote in the post that Beau came down in early July with "what seemed like a normal virus," which then developed into ADEM.

Her post put a spotlight on the condition, which affects mostly young children and is usually brought on by a viral or bacterial infection, according to the NINDS.

When ADEM develops, it causes inflammation in the brain and spinal cord that damages myelin, the tissue that surrounds nerves.

According to Boston Children's Hospital, the symptoms of ADEM may appear a few days or a few weeks after a viral illness.

Symptoms for parents and caregivers to watch for in kids include confusion, weakness, nausea and vomiting, headaches, unsteady walking, vision troubles, seizures and sensory changes like numbness and tingling.

The type of symptoms a child experiences depends on where the inflammation is located within the brain and spinal cord, according to the hospital.

Fortunately, most people with ADEM recover completely and the condition is rarely fatal, according to the NINDS.

For some kids, recovery may take a few days, while for others it may take up to one year, according to Boston Children's Hospital.

Treatment for ADEM typically includes steroid medications to reduce inflammation.

While ADEM can reoccur, for 80% of children, the condition occurs only once, according to Boston Children's Hospital.

The hospital notes that for kids who have had ADEM, it is important that they continue to be monitored by a health care provider. This is because while most children recover fully from ADEM, there's a small chance of recurrence or long-term complications that may require ongoing management.

In some cases, children who have ADEM can later develop multiple sclerosis, an autoimmune condition that Sigler was diagnosed with in 2001.

MS is an autoimmune condition in which the body attacks myelin, according to the NINDS. The condition mostly affects adults.