A woman started making so many mistakes at work that despite her decade of supercompetent service to the company, she was in danger of being fired. Noting her mom’s growing confusion, concentration problems and uncharacteristic irritability, her daughter wondered if Alzheimer’s was setting in. But then the mother’s doctor diagnosed a completely different problem called hepatic encephalopathy (HE), a brain disorder that develops when the liver is unable to remove toxic substances from the blood. Toxins such as ammonia then build up and travel through the bloodstream to the brain, impairing cognitive function.
HE most often develops in people with cirrhosis (scarring of the liver) caused by hepatitis C, alcoholism or other conditions. (The woman above had contracted hepatitis many years before her concentration problems surfaced.) HE also can occur in the absence of cirrhosis in people who, for any of various reasons, develop acute liver failure. HE hospitalizes, on average, 200,000 individuals each year in the US. The condition can be acute or chronic.
Symptoms of HE can worsen gradually or suddenly. Mild HE symptoms include poor concentration, forgetfulness, mild confusion, mood problems, impaired math and handwriting skills, changes in sleep patterns and a musty, sweet odor to the breath. More severe symptoms include lethargy, apathy, disorientation, slurred speech, obvious personality changes, marked confusion and amnesia. In very severe cases, HE patients may experience brain swelling, then lapse into a coma and die.
Diagnosing the problem: The early symptoms of HE can be subtle, so it’s easy for doctors to miss them. At a checkup, the patient might seem completely coherent—aware of the date and who the current president is, for instance. But then a family member will point out that the patient’s driving reflexes are slow, almost as if she were driving while intoxicated, or that the patient is having trouble focusing, or that she sometimes stays awake at night and sleeps during the day. Another possible clue that can appear in the early or later stages is a phenomenon called asterixis, in which (for reasons that are not fully understood) the hands flap uncontrollably when the arms are extended.
While various tests can provide useful information, there is no laboratory or imaging test that can definitively diagnose HE. Thus, the diagnosis depends on excluding other possible causes for a patient’s dementia-like symptoms, given that various conditions can mimic HE…and, in cases in which a liver problem had not been previously detected, identifying the underlying disorder.
Help for HE: In some cases of acute HE, the condition can be reversed by addressing the underlying cause of the liver dysfunction. For chronic HE, treatment centers on minimizing symptoms. Treatment options may include…
- Avoidance of factors and/or prompt treatment of conditions that could increase the buildup of toxins in the bloodstream—for instance, constipation, dehydration, electrolyte disturbances, kidney problems, infection or the use of medications that tax the liver.
- Dietary changes that help reduce formation of ammonia and other toxins and/or speed the passage of food through the intestines. For instance, patients may be instructed to limit animal protein.
- Medication. Because the toxins responsible for HE arise from the gut, a laxative drug called lactulose may be used to speed the passage of food through the digestive tract and to help bind toxins so they can be eliminated in the stool. Antibiotics also may be prescribed to inhibit ammonia-producing bacteria in the gut. Exciting development: The FDA has approved the antibiotic rifaximin (Xifaxan) for treating HE. Rifaximin has been proven to decrease repeat HE episodes as well as hospitalizations and, unlike other antibiotics prescribed for HE, it has no serious negative side effects.
HE can lead to rapid deterioration—so if the above measures are not enough to keep the condition under control, a liver transplant may be the best option. In that case, a patient should be referred to a transplant center to begin the evaluation process. For many transplant patients, receiving a new liver cures the HE.