Sunday, April 15, 2012

Creeping Weakness - Interactive Feature - NYTimes.com

"You need to see a doctor," the woman told her 27-year-old daughter. "Really," she insisted. "I'm worried." Her daughter, who lived several states away, was visiting, and when the mother happened to see her go up the stairs, she was struck by how odd this simple, everyday action looked. Her daughter's slender hips rocked from side to side as she moved up the steps. It was as if she had to lift her entire body to bring up each leg. Her mother was certain that something was wrong.

SLOW CHANGES

At first her daughter resisted. She felt fine, she told her mother. And if the stairs did seem a little tougher lately, it was because she hadn't been working out. But in truth, her friends had also commented about the way she went up stairs, and she had noticed a few worrisome things herself. She had recently gone skiing, for example, and even the easiest moves — maneuvers she mastered as a child — seemed strangely difficult. She couldn't turn; she couldn't even snowplow.

So when she returned home from her mother's, she made an appointment with her internist, who promptly sent her to a neurologist. When questioned by that doctor, the patient acknowledged that she was aware of some subtle changes in her strength for several years. In high school and early in her college career she was very active: she ran, swam, rowed. She hadn't been exercising regularly since college. But when she tried to complete the everyday tasks of normal life, she realized that they seemed harder.

LOSING STRENGTH

On exam, the specialist noted that the patient had some clear weakness in her thigh muscles. Indeed, she couldn't stand from a seated position unless she used her hands to push herself up. Even when she walked on a level surface, her hips swung from side to side — like a subtle parody of some femme–fatale sashay.

When thinking about a patient who has weakness, it's essential to distinguish between symptoms resulting from a problem in the muscle itself and those caused by the nerves that control the muscle. If it's a problem in the nervous system, you have to figure out which part of the system is affected: Is it in the brain? In the spine? In the muscle itself? Each location suggests a different set of diseases.

The neurologist was also intrigued by another possibility: the patient's mother was suffering from untreated Lyme disease when her daughter was born. Could this be a congenital Lyme infection? She thought it was an idea worth looking into.

Which test would be the least helpful in evaluating this patient?

  • MRI of the brain

  • MRI of the spinal cord

  • Dopplers of the legs

  • An electromylograph (EMG)

  • An ELISA for Lyme disease

More ...

http://www.nytimes.com/interactive/2012/04/13/magazine/diagnosis-creeping-weakness.html?ref=magazine