Think Like a Doctor
Solve a medical mystery with Dr. Lisa Sanders.
On Thursday, we challenged Well readers to solve the mystery of a 23-year-old man with episodes of aggressive, manic behavior that couldn't be controlled. Nearly 1,000 readers wrote in with their take on this terrifying case. More than 300 of you got the right class of disease, and 21 of you nailed the precise form of the disorder. Amazing!
The correct diagnosis is …
Variegate porphyria
The first person with the correct answer was Francis Graziano, a 23-year-old recent graduate of the University of Michigan. His major in neuroscience really gave him a leg up on this case, he told me. He recalled a case he read of a young Vietnam veteran with symptoms of porphyria. He's a surgical technician right now, waiting to hear where he'll be going to medical school next year. Strong work, Dr.-to-be Graziano!
The Diagnosis:
The word porphyria comes from the ancient Greek word for purple, "porphyra," because patients with this disease can have purplish-red urine, tears or saliva. The porphyrias are a group of rare genetic diseases that develop in patients born without the machinery to make certain essential body chemicals, including one of the most important parts of blood known as heme. This compound makes up the core of the blood component hemoglobin. (The presence of heme is why blood is red.) Patients who can't make heme correctly end up with too much of its chemical precursors, known as porphyrins. The excess porphyrins injure tissues throughout the body, but especially in the nervous system.
The disorder is characterized by frequent episodes of debilitating back or abdominal pain and is often accompanied by severe psychiatric symptoms. Patients with porphyria do not respond to most psychiatric medications. Indeed, many of these drugs make the symptoms of porphyria worse. Perhaps the most famous person suspected to have porphyria was King George III in the late 18th century — a diagnosis that remains controversial.
In this disease, when the machinery is stimulated to make heme — or any of the products that use this defective biological equipment — the precursor compounds known as porphyrins accumulate. Not only are these precursor chemicals unable to do what the final product is supposed to do, they can injure tissues throughout the body.
There are two main types of porphyrias. One primarily affects the skin, and the other affects the nervous system. A third type, which is what this patient was ultimately found to have, affects both. When the skin is affected, exposure to certain frequencies of ultraviolet light excite the excess porphyrins and causes skin to blister, itch and swell. The forms that affect the nervous system can cause pain in the chest, abdomen, limbs, or back; muscle weakness or cramping; nausea and vomiting; and personality changes or psychiatric disorders.
This patient (and supposedly King George III as well) had all of the above.
Attacks are usually caused by exposure to known triggers, including many medicines, smoking (either tobacco or marijuana), drinking alcohol, infections, stress and sunlight. These painful, often debilitating episodes can develop over hours or days and can last for days or even weeks.
This patient had many triggers for his attacks. He'd been taking antipsychotic medications, which are known to stimulate the production of porphyrins. He'd been in the sun. He'd stopped eating and sleeping – physiologic stresses that can cause attacks. He was smoking tobacco and marijuana.
Attacks of porphyria are usually treated with an artificial heme known as hematin. This drug is expensive and hard to obtain. It was the first orphan drug approved by the Food and Drug Administration and is made in the United States by only one pharmaceutical company. Before hematin was approved, porphyria attacks were treated with high doses of intravenous glucose, which works by temporarily shutting down porphyrin production.
How the Diagnosis Was Made:
Dr. Jory Goodman, the psychiatrist in this case, was intrigued by the story of this young man who had psychotic symptoms but did not respond to antipsychotic medications. He doubted that this was a psychiatric disease at all.
"I strongly suspect," he said, just 15 minutes after meeting the young man, "that your son has some type of porphyria." The patient's father dismissed the diagnosis immediately, saying: "He's already been tested for that. He doesn't have it."
"He hasn't really been tested for it until I test him for it," Dr. Goodman shot back. It's an easy test to do wrong, he told them. That happens all the time.
The patient was admitted to the hospital, and Dr. Goodman started the painstaking process of looking for a medical cause for his psychiatric symptoms. He ordered the tests for porphyria, giving explicit instructions on how the samples had to be handled so the test would be accurate.
Then Dr. Goodman ordered blood and urine tests to look for other possible causes of such symptoms in a young man. Certainly street drugs could cause at least a temporary psychosis. Heavy-metal poisoning, from lead or arsenic or mercury, is rare in the United States but can cause similar symptoms. Some autoimmune diseases can cause personality changes. So can deficiencies of vitamin B12 or folate, or disorders of thyroid hormone.
Initially only the marijuana screening test was positive. Then one of the tests for porphyria came back abnormal. The rest of the tests were done improperly and had to be resent. It wasn't enough to make a firm diagnosis, but when the patient became violent again, Dr. Goodman decided to start treatment with high-dose glucose.
The effect was immediate. As the sugar flowed into the patient's system, the shouting, the cursing, the struggling stopped. His face relaxed. His mother watched in amazement as the young madman was transformed back into the son she remembered.
After a half an hour, he turned to her and said, ''I don't remember the last time I felt this good.'' The pain in his back and his abdomen was completely gone. The snarling anger that had been his daily companion for months, maybe years, had vanished.
A second set of tests, this time done properly, finally provided the diagnosis: variegate porphyria.
A Patient Transformed:
Porphyria cannot be cured. Management is focused on avoiding triggers.
After feeling so much better from that first treatment, the patient was eager to learn how to avoid future attacks. Eating and sleeping regularly helps, he learned. He quit smoking; he quit drinking. He eliminated all the medications he could. Doing all this, he felt, finally, nearly back to normal, nine months after getting this diagnosis.
''This has changed my life more than I thought anything ever would,'' the patient told me recently. He's planning to go to work — something he had never been able to do — and he's hoping to return to college in the fall.
Dr. Goodman told me that this was the 19th patient in which he had diagnosed porphyria. "This is what I do all the time," he told me. "When you see symptoms you can't just think about the treatment. You have to think about the cause of the symptom, too. If you don't think of it you won't look for it. And if you don't look for, it you won't find it."
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