Porphyria attack after surgery can be easily missed: Case report
Woman's case demonstrates diagnostic challenge for doctors
Acute intermittent porphyria (AIP) attacks triggered by surgery can easily be confused with typical postoperative complications, a case report showed.
A 34-year-old woman had abdominal pain and low blood sodium levels after gallbladder removal surgery. Doctors initially suspected postoperative complications, but the woman revealed she’d had previous attacks of abdominal pain. She was then diagnosed with AIP and appropriately treated.
“This case illustrates the diagnostic challenge of acute intermittent porphyria in a young, otherwise healthy patient undergoing a routine [surgery],” the researchers wrote. It “demonstrates why healthcare providers must conduct detailed preoperative interviews because even the most minor of prior symptoms could be an indication for underlying porphyria,” they wrote.
The report, “Acute Intermittent Porphyria: A Rare Cause of Postoperative Abdominal Pain and Hyponatremia,” was published in Cureus.
Porphyria encompasses a rare group of diseases in which genetic mutations lead to the loss of enzymes needed to produce heme, a molecule that enables red blood cells to transport oxygen through the body. The molecules that produce heme —porphyrins and their precursors — accumulate to toxic levels.
Anesthesia may be a trigger
AIP is a porphyria type caused by mutations in the HMBS gene and a loss of the porphobilinogen deaminase enzyme. The porphyrin precursors aminolevulinic acid (ALA) and porphobilinogen (PBG) build up.
AIP symptoms usually occur in acute attacks that can last hours to weeks. They may involve severe abdominal pain, nausea or vomiting, neurological changes, dark-colored urine, changes in heart rate or blood pressure, and low blood sodium levels.
Attacks are often triggered by factors such as fasting, hormonal changes, medications, infections, or stress. Certain anesthesia medications may also trigger attacks.
“The perioperative period [the time around surgery] poses a high risk for porphyria attacks because fasting, surgical stress, and anesthetic agents can trigger these attacks,” the researchers wrote.
When AIP attacks arise after surgery, it’s easy for doctors to miss them, because a number of the symptoms can mimic other common surgical or postoperative complications, the team noted.
For the woman in the case report, symptoms began about 12 hours after gallbladder removal surgery with anesthesia. She experienced severe abdominal pain, an elevated heart rate, high blood pressure, and agitation.
The doctors initially thought her issues were due to a surgical complication, but abdominal imaging tests and other evaluations didn’t show any signs of that. Blood tests revealed low blood sodium levels and mild liver enzyme elevations.
At that time, the woman said she had intermittently experienced similar episodes of abdominal pain over the last year, all without an obvious trigger and resolved without treatment.
That information prompted the doctors to suspect porphyria. Urine tests showed elevations in PBG and ALA, confirming an AIP diagnosis. Treatment included four days of the AIP treatment Panhematin (hemin for injection), as well as saline to normalize sodium levels and opioids for pain management.
The woman experienced substantial symptom relief after a couple of days. She was sent home six days after surgery and referred for outpatient genetic counseling.
“Our case presentation demonstrates the difficulties of diagnosing AHP in a perioperative environment,” the researchers wrote.
They noted that while physicians may not suspect such a diagnosis in a young, healthy person without obvious risk factors, abdominal pain and low sodium levels after surgery should prompt an evaluation for porphyria.
While the anesthetic agents used in this case are usually considered safe for people with porphyria, careful monitoring is always key. These agents, combined with stress to the body from surgery, could still cause problems.
“The prevention of future attacks and long-term prognosis improvement depends on ongoing patient education and the avoidance of known triggers,” the team concluded.
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