European royal families may be enormously rich, but being a blueblood doesn’t always mean your blood is pristine. Queen Victoria’s DNA is famously believed to have silently bequeathed hemophilia to many of her descendants, including a great-grandson whose severe illness played a tragic role in spurring the Russian Revolution.
And that’s not all. Some have suspected that the British royal family DNA harbors porphyria, another genetic blood disease.
There’s plenty of skepticism about this theory, which seeks to explain the “madness” of King George III. But one thing is clear. If porphyria does indeed haunt the imperial bloodline that stretches to a new generation – the late Queen Elizabeth II’s great-grandchildren – any royal who’s afflicted going forward is likely to benefit mightily from modern treatment. While this disease may require lifelong vigilance, experts said in interviews that porphyria can often be controlled.
“If patients know they have the diagnosis, and they do the right things and avoid alcohol and risky drugs, most people will have few acute attacks,” said gastroenterologist Herbert Lloyd Bonkovsky, MD, of Wake Forest University, Winston-Salem, N.C., a leading porphyria specialist.
Heme infusions can also be helpful, he added, and the revolutionary new drug givosiran is available for those who suffer recurrent attacks. And “if all else fails, a successful liver transplant is curative” – as long as the transplanted liver doesn’t have porphyria, as happened in at least one case.
But, Bonkovsky cautioned, the diagnosis is often missed, in some cases for 15 years or more.
Diagnosing Porphyria: Awareness and Tests Are Crucial
Porphyria is caused when porphyins – essential components of hemoglobin – build up in the body, disrupting systems such as the nerves, skin, and gut. The urine can turn purplish, hence the condition’s name. (Porphyrus is the Greek word for purple.)
According to hematologist Danielle Nance, MD, of Banner MD Anderson Cancer Center in Gilbert, Ariz., acute intermittent porphyria “should be suspected in persons who have recurrent severe attacks of abdominal pain requiring strong pain medication to control symptoms, and there is no obvious physical cause.”
In such cases, practitioners should send out blood and urine for porphobilinogen (PBG) and delta-aminolevulinic acid (dALA or Delta-ALA) testing, Nance said. “These are almost always elevated, even between attacks, in persons with diagnoses of acute intermittent porphyria. Other types of porphyria, such as erythropoietic porphyria, may require additional testing. Genetic testing should be offered when a patient is suspected of having porphyria, as this can speed the diagnosis.”
The typical patient is a woman from age 18 to 55, often a young woman with recurrent abdominal pain that may occur during the second half of the menstrual cycle, Wake Forest’s Bonkovsky said. Constipation is common.
“She keeps coming to the clinic or emergency department, and no one knows what’s going on. Eventually, she tends to undergo an appendectomy, often a cholecystectomy, or sometimes gynecologic procedures without cure of the disease. Only after this long and arduous road of misdiagnosis does someone think it’s porphyria and do the correct tests.”
Bonkovsky led a 2014 study of 108 subjects (81% female) with acute porphyrias and found that the average time to a correct diagnosis was a whopping 15 years. Pain in the abdomen was the most common symptom (74%), followed by nausea/vomiting (73%), weakness (63%), and constipation (60%).
While underdiagnosis is common, porphyrias can also be overdiagnosed. According to Bonkovsky, a mild increase in urinary porphyrins is often misdiagnosed as porphyria when it may be a sign of liver disease or alcohol use, instead.
Hematologist Kleber Y. Fertrin, MD, PhD, of the University of Washington, Seattle, emphasized the importance of ordering the correct tests. “Urinary porphyrins are often inappropriately ordered because of their name. They are not diagnostic for acute hepatic porphyrias and may be nonspecifically elevated. It is paramount to get the labs from a reliable lab test experienced at performing diagnostic testing for porphyrias and make sure the urine sample needed is correctly obtained and preserved.”
New Drug Can Control Attacks, but It’s Costly
Treatment should begin right away if porphyria is suspected, without waiting for confirmation, Nance said. “There are porphyria experts in the U.S. and in many other countries who can help practitioners interpret symptoms and testing results if there is uncertainty or if treatment options are unclear.”
Patients are counseled to avoid attack triggers and eat healthy diets, she said. “Persons with porphyria are encouraged to have a plan for home management of an attack and when to come to the hospital for symptoms that don’t respond to home therapy,” she said.
Fertrin said “the typical treatment for an acute porphyric attack is the use of intravenous glucose, as well as intravenous hemin infusions, along with pain medications and fluids as needed. Some patients may need medication for high blood pressure. For patients with recurrent attacks, prophylactic doses of hemin can be used.”
Another option is givosiran (Givlaari), the biggest recent advance in porphyria treatment. It was approved by the Food and Drug Administration for acute hepatic porphyria in 2019. “It’s an inhibitory mRNA that shuts down heme synthesis by downregulating aminolevulinic acid synthase,” said hematologist Thomas DeLoughery, MD, of Oregon Health & Science University, Portland.
A 2020 study coauthored by Bonkovsky found that the drug reduced the mean annualized attack rate in acute intermittent porphyria by 74%, compared with placebo (P < .001). “Givosiran led to lower levels of urinary ALA and porphobilinogen, fewer days of hemin use, and better daily scores for pain than placebo,” the study authors write. “Key adverse events that were observed more frequently in the givosiran group were elevations in serum aminotransferase levels, changes in serum creatinine levels and the estimated glomerular filtration rate, and injection-site reactions.”
Bonkovsky said the drug is appropriate in patients whose disease is not controlled by lifestyle interventions regarding alcohol, smoking, and substance use. However, while givosiran is helpful, “it’s not a cure,” he said. “Probably about 40% of patients have found the side effects such as nausea, fatigue, headaches, and liver injury to be too adverse and have not decided to take it in the long term.”
In addition, the drug costs about $500,000 a year, and insurers may balk at the expense. Still, specialists say it can be a good option. “Before givosiran, the standard therapy was hematin, which decreased the activity of the ALA synthase,” DeLoughery said. “This is a nasty drug that can inflame the blood vessels and is not all that effective.”
The Royal Family May Be Able to Breathe Easy
There are other forms of porphyria besides the acute type. Cutaneous porphryias can cause blistering from sunlight exposure, and treatment is avoidance of such triggers, Fertin said. “For a rare form called erythropoietic protoporphyria, there is a subcutaneous implant with a medication called afamelanotide that increases tolerance to sunlight.”
There’s another type: variegate porphyria, which UpToDate says is “characterized by cutaneous blistering and/or acute neurovisceral attacks.” In 1966, a mother-and-son psychiatrist team theorized that Britain’s King George III suffered from this type of porphyria.
However, researchers have sharply criticized the porphyria theory with regard to that king, and a recent theory now suggests that he actually had bipolar disorder. Fertin is among the skeptics, noting the high prevalence of porphyria in affected families.
“Since King George III would now have a living number of relatives of about 900 people, we would expect around 180 cases of variegate porphyria to be connected to him, and those are nowhere to be found,” he said. “The idea that it could cause progressive psychosis and dementia is also a misconception. We do not find that porphyria is the underlying cause of psychiatric conditions on their own. Many atypical symptoms of the king were attributed to variegate porphyria, and the few more typical symptoms he reportedly had, of abdominal pain and urine discoloration, can be more easily explained by common diseases, such as kidney stones or gallstones. Finally, attempts at obtaining genetic or biochemical evidence of porphyria from relatives of King George III have been negative or inconclusive.”
That’s good news for the royals, who have many other concerns these days.
Nance discloses research study funding from Alnylam (maker of Givlaari) and payments to participate in educational activities for patients and practitioners. Bonkovsky discloses relationships with drugmakers who have developed products to treat porphyria including Alnylam, Mitsubishi Tanabe, Recordati, and Disc. Fertin is subinvestigator in a clinical trial for a novel treatment for erythropoietic protoporphyria sponsored by Mitsubishi Tanabe. DeLoughery reports no disclosures.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
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