What is AIH?
Autoimmune hepatitis (AIH) is a chronic disease that occurs when patients’ immune systems attack their livers and sometimes damage them. With treatment, most patients don’t need liver transplants and have normal life expectancies.
AIH is caused by an overactive immune system that attacks normal liver cells because it mistakes them for foreign agents such as viruses or bacteria.
A hepatologist or gastroenterologist typically diagnoses a patient with AIH based on blood tests and a liver biopsy.
While the exact cause of AIH is unknown, scientists believe both genetic factors and environmental exposures cause AIH.
Patients with AIH can experience a wide range of symptoms. Up to a third of patients have no symptoms when diagnosed, while others may have debilitating complaints.
Most AIH patients are successfully treated initially with steroids and later with the addition of other immunosuppressants.
AIH is caused by an overactive immune system that attacks normal liver cells because it mistakes them for foreign agents such as viruses or bacteria. It's a rare autoimmune liver disease that affects all ages and ethnicities; however, it affects men and women disproportionately.
AIH is a chronic disease that is treated long-term, often for life. There is no cure for AIH, but the disease can be controlled through medication. It is not contagious.
Estimated AIH cases in the United States:
20 per 100,000
3 per 100,000
Up to 45% of AIH patients have at least one additional autoimmune disease besides AIH. Patients are more likely to have multiple autoimmune diseases if they have a first-degree relative (parent, child, or sibling) with an autoimmune disease. In fact, 50% of AIH patients have a first-degree relative with an autoimmune disease.
Most common autoimmune diseases occurring with AIH:
AIH is a disease characterized by overactive immune cells in the liver. Recent studies have shown that the rates of autoimmune disorders (such as Type 1 diabetes, rheumatoid arthritis, and celiac disease) are increasing in many regions worldwide. AIH seems to be no different. Scientists believe this increase in autoimmune diseases could be related to new exposures (such as new medications, sanitation practices, and pollutants) in our environment.
A normal immune system is made of inflammatory cells that protect against organisms like bacteria and viruses. When patients have AIH, the immune system becomes overactive, and the inflammatory cells identify the patient’s own liver cells as foreign and attack them.
This ongoing inflammation in the liver may result in the development of scar tissue (fibrosis) that can become more severe over time. When the scar tissue becomes advanced (cirrhosis), it can restrict blood flow through the liver and cause . Without treatment that controls inflammation, patients with no or mild fibrosis are at risk of developing more severe fibrosis over time, and, eventually, cirrhosis.
How autoimmune hepatitis affects the liver:
inflammatory cells attacking viruses & bacteria
liver of an AIH patient
inflammatory cells also attacking healthy liver cells
Scientists believe that AIH, like many other autoimmune diseases, is caused by genetic risk factors and environmental exposures. Various medications (nitrofurantoin and minocycline, among others) and some viruses (Epstein-Barr virus, cytomegalovirus, herpes, hepatitis A, B, and C, and parvovirus B19) have been associated with AIH. Other environmental factors have also been considered, such as significant stress and chemical exposures.
The initial and long-term symptoms associated with autoimmune hepatitis are commonly different among patients. There is a wide spectrum of complaints in patients with AIH. It remains unclear why these symptoms are present in some and not in others.
Symptoms reported to be associated with AIH:
loss of appetite
abdominal discomfort, including pain in the right upper quadrant.
dry mouth or eyes
A is commonly ordered to help establish a diagnosis of AIH and to see if there is any scarring of the liver. A is a noninvasive test that doctors often use to track liver stiffness (fibrosis) in patients after diagnosis.
During your exam, your provider will likely ask about prior viral or bacterial infections, other autoimmune diseases you may have, and a medical history for first-degree relatives (parents, siblings, and children). The doctor will probably order blood tests to determine if you have ongoing liver inflammation and
A gastroenterologist or hepatologist typically diagnoses a patient with AIH based on a patient’s symptoms, a physical examination, blood tests, and a liver biopsy. Your primary care doctor may be the first to see you because of symptoms or abnormal liver tests.
Before a diagnosis of AIH is made, a hepatologist or gastroenterologist will rule out other causes of liver injury (for example, fatty liver disease) and may ask questions about alcohol and drug use including prescribed medications, vitamins, supplements, and recreational drugs to determine if these could have contributed to liver injury.
Primary types of AIH:
Type 1: 90%
Characterized by antinuclear antibodies (ANA) and/or smooth muscle antibodies (SMA)/anti-actin antibodies*. The onset can occur at any age, but it typically happens in adulthood.
Type 2: 10%
Characterized by antibodies to liver kidney microsome type 1 (anti-LKM1)*. The onset is more likely to occur at younger ages, and these patients usually require long-term immunosuppression.
*Up to 20 percent of patients may have seronegative AIH in which classic antibodies are absent.
Immunosuppressants decrease liver inflammation and help prevent additional liver damage by guarding against further destruction of liver cells. Once medication for AIH is started, liver tests typically return to normal within a few months.
Different types of treatments and medications:
Fast-acting steroids like prednisone or budesonide quickly reduce liver inflammation and “put out the blaze.”
Long-term immunosuppressants like azathioprine prevent further liver damage and possibly reverse existing fibrosis to “extinguish the embers.”
As liver enzymes approach normal levels, doctors often reduce the steroid medication and add a long-term immunosuppressant. Common long-term immunosuppressants used in AIH include azathioprine (Imuran), 6-mercaptopurine (Purixan or Purinethol), and even mycophenolate mofetil (Cellcept). Before beginning azathioprine, it’s recommended to have a TMPT blood test to help determine optimal doses of azathioprine or 6-mercaptopurine. Many patients are able to come off steroids completely; however, some may need to remain on low doses in addition to long-term immunosuppressants. Many patients will remain on medication for the rest of their lives, but a small percentage of patients will be able to stop taking long-term immunosuppressants after a few years of treatment.
Living with AIH:
Patients being treated for their AIH do very well long-term, and most will never need a liver transplant In a diverse group of patients (including patients of advanced age), 91 percent are still living after 10 years and 70 percent are still living after 20 years.
Some patients may experience increases of liver tests while on immunosuppression. Patients often refer to these episodes as “flares.” It is not completely clear why flares occur, but some doctors think that either the immunosuppression medication may not have provided excellent control of liver inflammation or a separate condition has caused the increase, such as a viral illness, stress, or another liver condition like fatty liver disease. Patients who don’t take their medication consistently could also increase their risk of a flare.
When experiencing a flare, some patients may notice the recurrence of symptoms associated with AIH such as worsening fatigue, itching, joint pain, and gastrointestinal complaints, among others. Be sure to report any significant changes in your symptoms to your doctor. After a flare, your doctor may prescribe steroid medications again or adjust your long-term immunosuppressant dose or frequency.
Fibrosis can sometimes be reversed with good control of liver inflammation. Often doctors will follow fibrosis levels with the use of noninvasive testing such as FibroScans. Some doctors may order a repeat liver biopsy to track the level of fibrosis and liver inflammation. It is uncommon for doctors to order repeat liver biopsies less than two years apart.