19 January 2013

What's wrong?

For whatever reason, some patient visits are more memorable than others. One diagnosis that has stuck in my mind wasn't even a diagnosis.

I asked my patient, "What brings you into clinic today?"

"My urine is dark, even though I've been drinking a lot of water."

Dark urine can be a sign of something ominous, like bladder cancer, or a kidney stone, or an inborn inability to metabolize certain types of protein ("maple syrup urine disease"), or a severe reaction to certain medications and recreational drugs. I started whittling away at my differential diagnosis by asking questions.

"Has your urine looked like it's had blood in it?" "No."

"Does it smell different?" "No."

"How long has this been going on?" "A few days."

"Is your urine brown, like the color of Coca-Cola or maple syrup?" "No."

"Is there pain when you urinate?" "No."

"Are you feeling pain anywhere?" "No."

"Have you noticed any change in your weight?" "No."

"Is there something happening in your life or the life of a loved one that's made you concerned about your health?" "No."

"Have you had vomiting, fever, headache, or any change in bowel habits?" "No."

No red flags. I asked a few more questions, each with an innocuous response. I checked to see if he was tender in his abdomen or his back (which could signal a kidney stone). He was not.

My history and physical exam had turned up nothing suspicious. After consulting with the physician, I ordered a dipstick urinalysis (a quick test for various abnormalities in the urine) and asked the patient to provide a urine sample. After a couple of minutes he returned with his specimen cup. I held it up.

"Is this about as dark as your urine has gotten?" I asked.


"And do you consider this dark?"

"Yeah! I mean, isn't it?"

No. His urine wasn't dark. It was quite pale. And that was the moment that I realized that nothing was wrong with this patient. He didn't need to be in the examination room. He ought to be at home, or at work, or shopping for groceries. Anywhere but here.

I was surprised that I took so long to arrive at this conclusion. But when I had assembled my mental list of potential diagnoses, "nothing" was not among the options I had considered. I had become so accustomed to patients having problems warranting diagnosis and treatment that it had hardly occurred to me that a patient might come in to clinic with nothing the matter.

I was reminded of a time I attended a play, and partway through, the actors "took down the fourth wall" and began speaking directly to the audience. It was a bewildering experience, because all of the sudden, the normal rules of theater did not apply. This patient encounter left me feeling similarly disoriented.

The patient's urinalysis results came back a few minutes later, showing no abnormalities. The doctor and I reassured him that things appeared to be all right, and we sent him on his way.