Teen girl with encephalopathy diagnosed with AIP: Case study
Patient suddenly began having seizures, changes in her mental status
A 15-year-old girl who developed seizures and changes in her mental health status was diagnosed with acute intermittent porphyria (AIP) associated with encephalopathy, or changes in brain function, a U.S. study reports.
The clinicians noted her initial presentation was confusing with apparently unrelated symptoms. However, the girl did show classic symptoms of AIP, including abdominal pain, neuropsychiatric symptoms, and dark reddish urine.
“This case demonstrates a diagnostic challenge posited by a presentation of new onset seizure and encephalopathy due to acute intermittent porphyria, a rare and often overlooked condition in pediatrics,” the researchers wrote. The case study, “Porphyric encephalopathy in a 15-year-old girl: A case report,” was published in SAGE Open Medical Case Reports.
AIP, the most common form of acute porphyria, is caused by mutations in the HMBS gene that lead to a deficiency in an enzyme needed for producing heme, a molecule that enables red blood cells to transport oxygen. As a result, intermediary molecules like porphobilinogen and aminolevulinic acid, accumulate to toxic levels, leading to the disease’s symptoms.
Reaching a diagnosis of AIP
Here, researchers described the case of an teenage girl who suddenly started having seizures and changes in her mental status, and was ultimately diagnosed with encephalopathy secondary to AIP.
The girl went to the hospital with new onset seizures and her parents indicated it was difficult to wake her up that morning. They also said she was confused during the trip to the hospital and had been unresponsive with stiffness in the extremities.
When she was first examined she had high blood pressure and abdominal pain, was anxious and confused, and appeared to be abnormally thin. The girl indicated she had worsening abdominal pain in the last seven days, with vomiting and minimal food intake, and had just completed her menstrual cycle. She said she’d smoked marijuana and vaped nicotine.
The girl started intravenous (into-the-vein) treatment with ondansetron to prevent nausea and vomiting, and maintainance fluids. Testing indicated she had high white blood cell counts, along with low calcium and potassium. She also had high blood sugar levels and elevated liver enzymes. A growth chart analysis indicated she’d lost 62 pounds (about 28 kg) in the last two years.
A few hours after she was admitted, she had a tonic-clonic seizure that started with stiffening of her right leg and was followed by whole body shaking for three minutes. She was started on levetiracetam, an anti-seizure medication. A video electroencephalogram, an exam that detects changes in the brain’s electrical activity, suggested mild cerebral dysfunction, while an MRI raised suspicion about potential vascular or brain inflammation.
Brain inflammation due to an autoimmune condition, along with viral infections, liver or blood vessel inflammation, and connective tissue diseases were ultimately excluded.
On the fifth day, the girl had dark red-colored urine, but there were no red blood cells in her urine. This unusual finding, together with her neuropsychiatric symptoms and abdominal pain, raised the possibility of an acute porphyria attack. Testing revealed high levels of porphyrins and heme precursors in urine and blood.
Genetic testing revealed the presence of a disease-causing mutation in the HMBS gene that confirmed a diagnosis of AIP.
The girl started treatment with dextrose, a type of sugar that can manage porphyria attacks. Her blood pressure remained high and abdominal pain persisted, however, and treatment with intravenous hemin was started.
Within two days, her symptoms eased. After four days, she no longer had abdominal discomfort, her neuropsychiatric symptoms resolved, and she recovered her appetite. As her condition stabilized, she was discharged on levetiracetam and amlodipine for high blood pressure. The girl did return to the clinic for follow-up, including AIP management.
“It is critical for pediatric providers to correctly and quickly recognize, diagnose, and treat porphyric encephalopathy in children, particularly adolescent female patients presenting with abdominal pain and neuropsychiatric symptoms,” the researchers wrote.
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