A month ago an oncologist called and asked me to see one of my heart failure patients whose chronically swollen legs seemed unusually blue but not cold.
Before I could get him in to see me, he ended up seeing a colleague, who called me up and said the man’s legs were cool and there was no Doppler in that office to check for pedal pulses. The man was sent for an urgent CT angiogram with runoff.
The test was perfectly normal. He had clean arteries.
When I saw him, the legs were less blue than they must have been and they felt OK but he had what looked like a shingles rash around his right elbow. There was some surrounding swelling and redness, so I prescribed an antiviral, an antibiotic and prednisone and arranged to see him back.
My diagnosis was erythrocyanosis. I have never seen a case but my instinct when I saw him was that this was a peripheral thermal regulation problem. So, a little bit of searching on the Internet gave me the diagnosis.
In follow up, the legs looked fine and the elbow rash was drying up nicely.
None of my research suggested a reasonable treatment option for his condition. But he was getting better so I didn’t have to worry about it at that moment.
A few weeks later I saw a young woman who spends her free time in a horse barn. She had a bluish discoloration of her outer thighs on both legs with some red spots scattered throughout the affected area. She told me she had had something similar a year or two earlier and her doctor had given her five days of prednisone. It took three weeks for her symptoms to clear up.
As soon as she had finished telling me her story and showing me her thighs, I was able to tell her what her problem was and I could also tell her that horseback riding is one of the triggers. In her case she was just spending time in the cold barn but the trigger mechanism behind the condition is exposure to cold under any circumstance.
I told her I had seen a case of her condition just a little while earlier and that that man ended up with what seemed like a case of shingles and I wasn’t completely sure if that was connected.
“Well, I got shingles just after I had that first episode“, she said.
“That’s very interesting, let me do some googling to see if there is a connection”, I said.
I didn’t come up with anything while I saw her but I promised to look into it more.
All that came up within my research was that erythrocyanosis, also called pernio, closely related to chilblains, can cause blisters or skin ulcers.
Not long after that my elderly man with erythrocyanosis was back. This time he had swelling on his right elbow with a lot of scabs and his forearm was cold and blue. I have a Doppler in my office, so it took me almost no time to walk down the hall and get it and establish that the systolic blood pressure in his right arm was 140.
There was obviously an infection going on so I prescribed an antibiotic again, I skipped the antiviral but I did prescribe prednisone in case that had done anything good for him last time. I promised him to call our dermatologist in the big city to ask if there was anything more they could do for him. He has a follow up on Monday.
This afternoon I got a return call from a dermatologist, offering a few hints and also offering to give this patient priority and get him in before the nine month wait they usually have for new patients (the reality in a physician shortage area).
Hans Duvefelt is a family physician, author, and creator of “A Country Doctor Writes”
