Bodies Built Backward: Situs Inversus

Jan. 22, 2007 — -- Nine-year-old Kay Salomon is the picture of health. She enjoys many activities like skateboarding, surfing and swimming.

"I am kind of a big athlete," she says.

But Kay's mother, Kerry McAuley, lives in constant fear. This fear isn't just the worry of a normal parent, and McAuley's not just afraid that Kay will get hurt. She's constantly worried that Kay might die.

"I go in there many times during the night and check on her and make sure she's okay, wondering if this is the year or is it going to be in six months… when is she going to get sick on me?" says McAuley. "Because it could happen … it might not happen, but nobody knows."

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To understand McAuley's concerns, you have to understand what's happening inside her daughter. And we're not talking about getting inside Kay's head or understanding her feelings. We mean literally looking at her internal organs, which are all on the wrong side of her body.

That's right, her stomach, liver, spleen and the rest of her organs are all reversed. Kay's insides are the mirror image of a normal child's. It's a condition called situs inversus, and though rare, it's probably more common than you think, affecting about one in 10,000 people.

Situs inversus isn't necessarily a cause for alarm. Many people with the condition are actually perfectly healthy. But Kay has an added complication: corrected transposition of the great arteries. This means that parts of her heart are switched around as well. In her case, it's the upper chambers, or atria, and her great arteries. Amazingly, the blood still gets to the right place, just through the wrong connections.

"The easy way to look at that is two wrongs make a right," says Dr. Frank Hanley, a pediatric cardiac surgeon at Packard Children's hospital near San Francisco.

But Dr. Hanley says the odd structure of Kay's heart is not the main concern. Kay's biggest problem is a large hole between the lower chambers of her heart, or ventricles, and an obstruction under one of her valves.