One might wonder whether vampires actually existed beyond the tales of Transylvania, horror flicks featuring Bela Lugosi or the Twilight Saga. There may be a medical explanation that inspired the tales of vampires. A story I heard during a college lecture about the disease porphyria, and its inspiration for vampires helped me save a patient’s life years later as a physician.
The Story
Organic chemistry is one of the more difficult classes aspiring premedical students take before applying to medical school. It often “weeds out” the doctor wannabes, because if they can’t pass “orgo,” their hopes for medical school are dashed. Despite this reputation and my own struggles with orgo, my college organic chemistry professor, Dr. David Dolphin, found a way to make orgo fun. He showed up on our first day of class wearing a Canadian mountie’s outfit and played a Monty Python video with the “Lumberjack Song.” Needless to say, he immediately won over the students.
A good story can stick with you. Dr. Dolphin’s research field included the study of porphyria, a genetic disorder of heme synthesis, which is needed to make hemoglobin, a vital protein in our red blood cells for carrying oxygen throughout the body. In one class, he enthralled us with tales of vampires and their potential basis in porphyria. Porphyria patients have skin that is very sensitive to sunlight, which can cause blisters, ulcers, and scarring—prompting the necessity to avoid sunlight and only come out at night. Some may be anemic, and thus appear pale, with their pallor compounded by avoiding sunlight. Recession of the gums, in addition to significant scarring around the face leading to retraction of the lips around the mouth can give the impression of fangs. You see where this is going.
The pièce de résistance is that, because they are lacking heme, in the days before modern medicine, they may have tried to compensate for their impairment by drinking blood. Contrary to the typical vampire stories, they wouldn’t prey upon humans. Instead, they might obtain blood from animals.
There are multiple types of porphyria, and patients are often misdiagnosed. In addition to sensitivity to sunlight, one common problem some have is intermittent severe abdominal pain that requires narcotics for relief. This may lead to multiple, unnecessary abdominal surgeries.
With all these features, it should be easy to see how they might provide the seeds for a great horror story.
The Patient
The patient was a female in her 30s who was admitted for seizures. While she was in the hospital, her seizures were getting worse and not responding to the usual antiseizure medicines. Consequently, she was moved to the intensive care unit, where I was working as a medical resident. The neurologists put her on intravenous pentobarbital to induce a coma, hoping to stop the seizures. They also put her on a ventilator to support her breathing while she was in a coma. Things continued going downhill, and the seizures were not abating. We noticed, oddly, that her urine in the drainage bag was very dark—almost black. At first, we suspected she might just be dehydrated so we gave her boluses of fluid, but that didn’t change the urine color. Consequently, we sent off some urine for analysis. The surprising result: the level for urobilinogen in the urine came back off the charts.
When my fellow resident informed me of the high urobilinogen level, something clicked in my brain. I remembered the vampire story and that the excess amounts of heme precursors in porphyria were excreted in the urine and they cross-reacted with the test for urobilinogen. I said, “Do you think she has porphyria?” We immediately sent off additional tests for porphyria. They were positive! It turns out that pentobarbital is toxic for patients with porphyria and can actually induce a porphyria crisis. We switched her to another antiseizure medicine and were eventually able to control her seizures and get her off the ventilator. Making the diagnosis saved her life.
Lessons From The Patient
Although seizures are a known complication of porphyria, what initially made us suspicious that something was awry was her extremely dark urine. Although there are other disease states that can cause darkened urine, one characteristic feature in porphyria is that when their urine is exposed to light, it turns black. Once we made the diagnosis, all became clear.
There are a couple important lessons from this story. One is the power of a story to create indelible images that can be remembered. Hats off to professors, like Dr. Dolphin, for using a creative approach to instruction. If I had never heard about vampires and porphyria, I doubt I would have remembered the features of porphyria that led to making the diagnosis. The other key lesson is that physicians are trained to be astute observers of their patients, but they diagnose diseases based on what they know or what they have seen. Being able to synthesize a constellation of the patient’s history and physical observations in conjunction with laboratory and other tests helps us to come up with a diagnosis. Tying those skills to effective communication with the patient and their family members is ultimately the art of medicine.
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