Pediatrician Looks Past The Blame

"I went through a period of real grief," recalled Rivers, who by then had given up a busy pediatrics practice because her own children needed her more. Her life seemed consumed by illness.

By 2003, Rivers said, a doctor treating one of the children suggested that the underlying cause of their illnesses might be genetic, possibly an inborn error of metabolism, of which there are hundreds. Rivers said that possibility had also occurred to her.

One potential culprit was a form of mitochondrial disease, a group of genetic disorders that often go undiagnosed or misdiagnosed for years. These diseases, which can affect any part of the body or organ system, can range from relatively mild to fatal. They are caused by defects in the DNA that trigger a sort of "energy crisis," impairing the body's ability to burn food and oxygen to generate energy. Diagnosis is often extremely complicated, time-consuming and expensive, and it can involve biopsies of muscle or skin and many lab tests.

An estimated 4,000 children a year are born in the United States with some form of mitochondrial disease, according to the Cleveland Clinic. There is no cure, but the disorder can be treated, usually by taking an individually tailored regimen of vitamins and enzymes called a "mito cocktail" prescribed by a metabolic specialist. This cocktail typically includes B vitamins and an amino acid called L-carnitine.

In July 2004, after a phone consultation with a Hopkins specialist, Rivers took her children to see a pediatric geneticist there. The geneticist told Rivers that he thought the "picture was too confusing" and that blood tests were inconclusive. He didn't think the children had mitochondrial disease, but he wasn't sure what was wrong.

Next stop was the pediatric neurologist, who accused Rivers of exaggeration.

In November 2004 Rivers took John to see Greene at the University of Maryland. Greene said she was immediately struck by the fact that all three children were affected and that a variety of organ systems were involved.

"When you have a problem that involves so many systems, I tend to think of mitochondrial disease," said Greene, who has treated patients with the disorder since 1984.

"I've seen other families [with mitochondrial disease] where every kid was affected," she said. She told Rivers she wanted to see Emily, because she was the sickest.

"I started with an open mind," said Greene, adding that she first needed to rule out other possible causes. After several months of testing, mitochondrial disease still remained at the top of the list, but a definitive diagnosis would require a muscle biopsy. That procedure was performed in July 2005 at Children's Hospital in Atlanta.

The results showed conclusively, Greene said, that Emily had the disorder. Meanwhile John, Rivers and her oldest child, all of whom were found to have abnormally low levels of carnitine and other suggestive indicators, were started on a mito cocktail that Rivers said has significantly reduced their symptoms. Doctors no longer consider John to be autistic, according to his mother.

Greene said it isn't possible to say for certain, but she presumes that the other two children also have mitochondrial disease inherited from Rivers. Long attributed to exposure to a virus that causes hydrops, Emily's problems may actually be the result of severe mitochondrial disease.

"There's a tendency on the part of the majority of physicians to think that genetic causes are rare," Greene said. "They aren't."

Rivers said she feels responsible but tries not to dwell on the what-ifs. "Blame? You could wallow in that, and I've certainly had periods of it. Most days I don't have time to be depressed, because there's so much work to do."

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