(Cameron Cottrill for The Washington Post)

Amy C. Hughes was looking forward to a rare luxury: a leisurely weekday lunch with a friend at a restaurant near her suburban Philadelphia home.

Hughes, an engineer at Merck, had taken off the week after Christmas 2015 to spend time with her husband, Kevin, and their two children. The couple's son, Rion, then 13, had come down with a cold on Christmas Day and complained of a headache. A few days later, his pediatrician suspected a sinus infection and prescribed a three-day course of antibiotics.

"Nothing seemed unusual," Hughes recalled. But an hour after she headed off for lunch, she received an urgent call from her husband summoning her home. Three police cars and an ambulance were lined up in front of her house. A team of paramedics was attempting to manually resuscitate her son as they hurried out the front door. His eyes were closed and his body was racked by a violent seizure. Hughes later learned that the paramedics worried that despite their best efforts, Rion wouldn't make it to the closest hospital, 25 minutes away.

For the next six days, doctors tried to determine why Rion, who had been healthy, suddenly developed a life-threatening seizure that seemed impervious to even high doses of anticonvulsants.

The answer would turn out to be as disarmingly simple as it was uncommon. And while Rion has fully recovered, the emotional fallout from his frightening illness took longer for his mother to overcome.

"There was lots of anxiety for about a year, but it's no longer there," Hughes said. "I've thought a lot about what I could have done differently, and the answer is: Really nothing."

Amy C. Hughes with son Rion, whose life-threatening seizure went unexplained for days and seemed impervious to anticonvulsants. (Picture People) (Photo by Picture People)

'Seemed like an eternity'

As the ambulance carrying Rion roared off, Hughes and her husband followed in their car, a drive that "seemed like an eternity."

At the hospital, the ER staff peppered them with questions about whether Rion used drugs. The seizures suggested a possible overdose, and a CT scan showed no signs of a head injury, another cause of seizures.

"I remember saying, 'I can't believe you're asking me this even though I know you have to,' " said Hughes, whose father had been an emergency room physician.

Rion, she told the staff, has a mild form of autism and attention-deficit disorder; she wasn't sure he even knew what illegal drugs were.

In addition to the severity of the seizure they were struggling to control, doctors were worried about its extremely long duration. They believed Rion might have been having a seizure for more than an hour before his father discovered him and called 911.

"They kept saying, 'We don't know what he's going to be like when he wakes up,' " Hughes recalled. "I was terrified he had brain damage."

Because he was on a ventilator and needed specialized care, doctors at the community hospital decided to transport him to Children's Hospital of Philadelphia. Unable to medevac Rion — the helicopter had been grounded by wind — a specialized team from CHOP arrived in an ambulance. Hughes climbed in next to her son for the 45-minute ride.

Heavily sedated, Rion was admitted to the pediatric intensive care unit with a fever, and was given a spinal tap to look for an infection capable of triggering seizures, such as meningitis. He received three IV antibiotics and an antifungal drug, but no infection was identified in his spinal fluid.

Hughes tried to spend the night in the ICU with her son. "I sat there after they turned off the lights and watched all the displays and constant alarms and thought, 'He is going to die,' " she said. "I started hyperventilating. My blood pressure was 170/140 and my pulse was really high." The medical team wanted Hughes to go to the Hospital of the University of Pennsylvania's ER across the street, but instead she went back to a family room she had been assigned elsewhere at CHOP and calmed down.

After tests failed to reveal another cause, doctors told Rion's parents they suspected he had contracted a human metapneumovirus, a respiratory infection that typically affects the very young and the very old, and is most common in winter. The virus is typically mild and usually goes away without treatment in a few days; in some people, it can cause more serious illness.

Over the next few days, Rion began showing improvement and was taken off sedation and the ventilator and moved to a general pediatric unit.

Hughes was overjoyed that he showed no sign of brain damage. Other than slight coordination problems, she said, Rion was joking and "seemed like his old self."

To ensure that he was never alone, Rion's parents and his grandmother, a nurse, took turns staying in the hospital with him. At 6 a.m. on his sixth day in the hospital, his grandmother and mother awoke to find Rion in the midst of a seizure.

At that point, Hughes recalled, "I was in panic mode." Rion was still on anti-seizure drugs, although the dose had been lowered. Surely, his mother thought, the virus had cleared his system. So why was he having a seizure? Unlike the first, this one was quickly controlled with medication.

A few hours later, when the medical team made rounds, Hughes questioned the doctors. They told her they thought some of the virus might still remain in his system, but they were upbeat about his progress. The plan was to send him home the following day, with instructions for an MRI scan of his brain in four to six weeks.

"I thought, 'He can't come home,' " Hughes remembers. " 'What if he has a seizure in the middle of the night and stops breathing?"

A frightening finding

Hughes asked if the MRI could be done while Rion was still in the hospital. She had struck up a rapport with Stacey R. Rose, the pediatrician on duty, and hoped Rose would agree.

"Mom and I had a lot of discussions about whether we felt comfortable" having Rion go home, Rose recalled. Doing an MRI at this point carried some risk, because a test in the ICU had revealed possible damage to Rion's kidneys. There was concern that the dye used in the MRI could harm his kidneys; waiting looked like a safer bet.

But Rose decided that the potential benefit outweighed the risk, and she ordered the scan.

That night, Rion was still in the MRI machine when a neurosurgeon approached Rion's father in the waiting room.

The scan showed that Rion had a massive infection in the subdural area of his brain that had breached the bony flap separating the brain from the sinuses. The infection had formed an abscess called an empyema, which triggered the seizures. Other symptoms of a subdural empyema include headaches and lethargy.

Before the advent of antibiotics, the condition, which is rare, was uniformly fatal. The problem disproportionately affects males between ages 10 and 40, and typically occurs during the winter.

Rion, his father was told, would need a procedure to relieve pressure that had built up inside his skull, and the area would need to be rinsed to rid it of infection. Surgery was scheduled for first thing the following morning, the neurosurgeon said — sooner, if his condition deteriorated.

That night, Hughes slept in Rion's hospital bed, holding him "as if I could protect him from having another seizure." He had none, and the surgery was successful. Nearly a week later, Rion went home.

Hughes said she asked doctors why they hadn't suspected an abscess, and was told the disorder is rare; she said she later learned that CHOP sees about one case a week in winter. Rose suspects the CT did not show the abscess because the test was not performed with contrast dye; an MRI scan is the definitive test used to diagnose it.

It's unclear why Rion developed an empyema. "I think it's just bad luck for some kids," Rose said.

Hughes suspects that Rion's high pain tolerance might have complicated the clinical picture. "When I asked him, he said he had a headache," Hughes said. But the pain was controllable with over-the-counter pain relievers and never seemed especially bothersome. Rion had developed some swelling over one eye — another possible sign of an abscess — but that had largely receded after he took the oral antibiotic.

What would have happened had Rion been discharged before being diagnosed?

Rose chose her words carefully. "He would have continued to have seizures and fever and worsening headaches, and he would have returned to care at that point," she said. "He could certainly have had a poor outcome."

The diagnosis, she said, surprised the medical team. "I think it's always important to be questioning the diagnosis," she said. "It's good to reevaluate."

Hughes, she added, was a "great advocate" for Rion.

Hughes said she will be forever grateful for the care her son received and especially to Rose "for listening to my concerns. I truly believe she saved his life."

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