Sunday, October 4, 2009

A Toddler's Unexplained Illness May Be Kawasaki Disease - NYTimes.com

"Honey, Dr. Wolffe wants to take a look at you," the father said as he turned off the television. The 18-month-old toddler scrambled up from the floor and walked over to the familiar figure now sitting at his dining-room table. The child looked up into the round, friendly face of Dr. Wolffe Nadoolman. The pediatrician immediately noticed that the whites of the boy's eyes were bright pink — a nearly uniform tint everywhere except for a slender band of normal white surrounding the iris. Unlike in a typical case of pinkeye, there was no crusting or discharge from the eyes, no tearing. The pink eyes didn't seem to bother the boy, and yet this was why the doctor was making a house call. He was worried when the boy's parents called to report one more new and unusual symptom.

Nadoolman saw the toddler the day before in his Berkeley office. His parents brought him in because he'd had a high fever for nearly a week with no other symptoms. The fever would spike to 103 degrees, and though the acetaminophen and ibuprofen would bring it down, his temperature never returned to normal. Neither had the boy: for the past week he had been tired and cranky. His appetite was gone, and he had been waking up at night, something he hadn't done for nearly a year. Did he have meningitis? the mother worried.

How is your older child? Nadoolman asked about the boy's 5-year-old brother. He had a couple of days of fever the week before, the mother reported, and now had a couple of canker sores in his mouth, but otherwise he was fine.

On examination, the younger boy had a low-grade temperature of 100.6 despite the acetaminophen and ibuprofen he was given a couple of hours earlier, but other than that, the exam was unremarkable.

Five days of fever is unusual for most childhood illnesses, and although Nadoolman often sent kids for lab work at this point, this child didn't appear sick enough to need that. It was likely that he had what his brother had the week before. The combination of fever and canker sores made Nadoolman suspect a coxsackievirus — one of the most common causes of fever in very young children. It could also be roseola — another common childhood viral illness. Roseola is caused by a herpes­virus and is characterized by several days of high fever followed by a bright pink rash that usually starts as the fever begins to subside. Neither of these infections needed treatment other than the fever reducers they were already giving the toddler.

The doctor paused. There was another possibility — Kawasaki disease. Although rare, it was most common in boys of Asian descent — as this child was — and in this age group. Kawasaki, he explained, is an inflammatory disease of the blood vessels. No one understands what causes it, but the disease, if not diagnosed and treated promptly, can cause permanent damage to the heart and early death. The most common symptom was a prolonged fever accompanied by a rash. Typically the rash affected the fingers and toes, causing them to swell and then peel. In his office, he told the boy's parents that they should call him if he developed any kind of rash at all. Pink eyes or lips were another frequent symptom.

When the doctor called the next morning, the boy still had the fever, but no rash, no redness, no other new symptoms. Then late that afternoon the boy's mother noticed that his eyes were pink. When Nadoolman heard about the eyes, he told the parents he would make a house call at the end of the day. Now he was worried.

After looking at the boy's eyes, the doctor moved on to examine the rest of the child's body. The only new finding was a single canker sore on the inside of the boy's lower lip.

In medicine we are taught that any given collection of symptoms is far more likely to be an unusual presentation of a common disease than even a classic presentation of a rare one. So was this an unusual case of a coxsackievirus infection? Or was this early Kawasaki disease? The prolonged fever, the pink eyes and the presence of only a single ulcer — usually there are several — would make this an unusual case of coxsackie. As for Kawasaki — there is no definitive test. Doctors use clusters of symptoms to make the diagnosis. While the boy had two of the symptoms of Kawasaki disease — prolonged fever and pink eyes — you needed at least five to diagnose this disease definitively. But damage to the heart could occur even without a full-blown presentation of the disease. And Kawasaki was thought to be widely underdiagnosed. Postponing treatment beyond 10 days after the start of the fever significantly increased the risk of heart damage.

Let's give it another day, he told the parents.

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http://www.nytimes.com/2009/10/04/magazine/04FOB-diagnosis-t.html?ref=magazine&pagewanted=print