Lot's Son

A CF story

In 1993, I discovered an unusual side effect of having cystic fibrosis.

I wasn't expecting anything of this sort to happen. It was actually the furthest thing from my mind. I was on my way from Albany, NY to Woodbury, TN, starting a vacation with someone I loved. The trip was almost exactly one thousand miles, and took two days.

Travel was easy for most of the trip. The problem came in Tennessee. Somewhere along that long, long stretch of I-40, traffic came to a standstill. For miles and miles, bumper to bumper traffic inched along, stopping and going. Construction was the cause. The construction signs at least told us how many more miles we'd have to suffer through.

And suffer we did. The temperature was in the mid-90s Fahrenheit, the humidity was high, and there was no wind. My car, coming from New York, did not have air conditioning. So I suffered, and sweat.

Oh, what sweat! My left arm -- the one in the sun -- was literally sheened with sweat from the shoulder to my fingers. It was horrible: the heat, the humidity, the stifling boredom.

Eventually I passed the construction site and picked up speed. Traffic went back to normal. It felt so good to have air blowing over me, cooling me down.

Some time later I looked at my left arm. What is this?, I wondered. Along my arm were little trails of white. Starting from the back of my hand and extending along my arm were what looked like fine white sand grains. The grains were sparse on my arm, and concentrated in between my fingers. They felt like fine grit.

On close inspection, I found that the lines followed the blood vessels underneath my skin.

Having a scientific bent, after observing this strange phenomenon, I formulated a hypothesis, designed an experiment, and noted the results. I placed a few grains of this unknown substance on my tongue. My hypothesis was correct: the substance was salt.

What had happened was that the sudden increase in speed had rapidly cooled the sweat on my arm. This sudden evaporation carried away the water, leaving behind the salt. My arm was laced with trails of sodium chloride.

[People with CF have abnormally salty sweat due to abnormal chloride ion transport. (This difference forms the basic diagnostic test for CF.) I'd known that my sweat was salty -- its conductivity was higher than my dad's, for instance -- but I'd never seen it demonstrated so dramatically.]

What I still don't understand is why the salt collected in lines along my blood vessels. Did they cool faster or slower than the rest of my arm?

Whatever the science behind it was, the experience left me feeling like Lot's son. I didn't turn into a pillar of salt, but I did get a nice coating.

Last updated 3 June 2000
All contents ©1999-2002 Mark L. Irons