Dec. 23, 2008 -- Baylee Littrell, son of Brian Littrell, a member of the pop music group the Backstreet Boys, was finally diagnosed last week with Kawasaki syndrome, a collection of symptoms that stem from swollen blood vessels.
"He's never been sick," said Baylee's mother, Leighanne Littrell. When he first began to show symptoms, "it kind of blew us away and from then on things escalated."
In an announcement on Brian Littrell's Web site, the family detailed how Baylee, 6, was tested for several different infections including strep throat and hand, foot and mouth disease before being diagnosed with atypical Kawasaki disease.
Kawasaki disease or Kawasaki syndrome (KS) is characterized by a high fever that lasts about five days. Fever is usually accompanied by red eyes, a rash, red lips and tongue and swollen hands, feet and lymph nodes. If only some of these symptoms are present along with a high fever, the KS is called atypical.
"They look like they've been up all night," said Dr. Robert Frenck, a professor of pediatrics in the division of infectious diseases at Cincinnati Children's Hospital Medical Center. The lips can look coated with red lipstick. "Kids get very fussy and irritable. ... They're just not themselves."
Although KS causes inflammation in blood vessels throughout the body, the most serious cases occur when blood vessels surrounding the heart become inflamed. Unless they are caught early -- within 10 days after the onset of symptoms -- the inflammations can cause a variety of heart complications including aneurysms, abnormal heart rhythms and heart attacks.
Standard treatments for KS include high doses of aspirin to reduce fever and overall swelling and an immunoglobulin to reduce arterial inflammation and prevent heart complications.
The Great Mimic
But the problem with a syndrome such as KS is that the beginning stages can look like almost any viral or bacterial infection.
"People do call it the great mimicker," said Dr. J. R. Bockoven, the director of outreach and education for the Heart Center at Akron Children's Hospital. The initial fever and redness symptoms can look like almost any viral or bacterial infection, from the common cold to measles.
But Baylee was "atypical in everything," Leighanne Littrell said. His symptoms were varied and did not occur in the order associated with KS.
Leighanne Littrell said she believes Baylee's KS began at the end of October when he got a rash on his legs that lasted for almost three weeks. Since then, he had been under the weather with a stuffy nose and an occasional sore throat, but nothing serious enough to see a doctor about.
"I think his body was fighting off this disease," she said.
Baylee's acute symptoms began, not with a high-grade fever, but with swollen lymph nodes that felt like pecan nuts under the skin.
Baylee was first diagnosed with strep throat, but then he developed a fever and went back to the doctors with ulcers in his throat. After several different diagnoses, Baylee developed a full body rash that his mother said looked almost like a chemical burn.
Still, his lab tests and blood work showed no signs of a serious disease. Finally, on the day Baylee was supposed to be released from the hospital, Leighanne Littrell made a request of her own on a hunch that something was still amiss.
"I said, 'before we go, I would love an echocardiogram,'" Leighanne Littrell said.
The Heart of the Problem
Leighanne Littrell said she is concerned that children who are misdiagnosed or diagnosed too late because their parents or their doctors aren't aware of the syndrome will suffer from KS-related health problems later in life. KS is a leading cause of acquired heart disease in the United States.
"Listen to your instincts and hopefully you're wrong, but maybe you're right," Leighanne Littrell said.
Heart problems are not unknown to the family. Brian Littrell had two heart surgeries: one at age 5 to correct a heart murmur and again at age 23 in 1998 to repair a hole in his heart.
But KS is not hereditary. The latest data and theories suggest KS is viral or bacterial in nature because of how it presents; because it is seasonal, occurring most often during the winter and spring; and because each person responds to the syndrome in a highly individual way.
"Certain kids have certain issues with it and certain kids won't," Bockoven said. "It's each specific body's reaction."
And there is still no definitive way to diagnose KS.
"There is no special test to be able to do to say this is Kawasaki," Frenck said. Aside from the hallmark high fever, "it can look like almost anything."
KS primarily affects children under the age of 5, though it can occur in older children. According to the Centers for Disease Control and Prevention, about nine out of 100,000 children have KS. Incidence is higher among Japanese and Korean children, though KS can occur among any ethnicity.
Baylee's follow-up treatments involve some echocardiograms to monitor swelling in the coronary arteries, doses of aspirin and possibly another course of immunoglobulin.
Brian and Leighanne Littrell are careful now to keep him from activities that might stress his heart.
"We're a little scared now," Leighanne Littrell said. "We don't know how to act. But he's acting perfect."
For being a model hospital patient, she said that Baylee received Batman and Superman outfits.
"He walked out [of the hospital] as Batman," Leighanne Littrell said. "He's our hero."
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