Definition
Hepatology is derived from the Greek word “hepatikos” which means liver and “logia” which means to study. Hepatology is the branch of medicine that specializes in the study of the liver, the gallbladder, the biliary tree, and the pancreas. Hepatologist, the term used for the specialist of this branch, also prevents, diagnoses, and manages disorders in these areas. This field was previously a sub-specialty of Gastroenterology but recent advancements in medicine and instrumentation allowed this sub-specialty to be better understood and to evolve into a freestanding specialty.
Educational Requirements
Bachelor’s Degree
To become a hepatologist, one must first complete a pre-medical bachelor’s degree. This degree should at least serve as the initial foundation of scientific knowledge and experience in laboratory and instrumentation. Even though there is no specific type of degree that is required, science-based programs that provides emphasis on the theoretical and practical science pre-requisites for medical school admissions as well as to pass the Medical College Admissions Test. This period of training will also serve as the period to create long term strategies and advance their knowledge for their future medical education. Early exposure of the medical field and patient care, like volunteering on a medical mission, is also recommended to develop confidence through experience and to show dedication to the medical field.
To ensure their entry to a good medical school, an aspiring medical school student should monitor their Grade Point Average (GPA). The student should obtain at least 3.0 cumulative GPA and a 3.0 or higher GPA for all science and lab work. It is also necessary for the student to establish good working relationships with their teachers and mentors. This will enable them to have an authority figure to guide them and remark on the student’s ability, work ethic, overall professionalism, and potential to be a successful physician. These remarks can provide the materials for the required letter of recommendation to be submitted to the institution that they are planning to apply to.
Medical College Admissions Test (MCAT)
The Medical College Admissions Test or MCAT differs from country to country. The test is usually taken during the junior or the senior year of the undergraduate degree. This test evaluates the depth of the taker’s knowledge on the fundamental concepts of the applicable sciences, problem solving skills, and critical thinking capability that they will need for medical school and professional practice. The MCAT exam score will be submitted along with the other application requirements to the student’s chosen medical schools. The acceptable MCAT scores varies from institution to institution and some of the schools accept MCAT scores from up to three years, allowing the students to gain additional training or experience between their bachelor’s degree and starting medical school.
Medical School
A medical degree, either a Doctor of Medicine (MD) or Doctor of Osteopathic Medicine (DO) degree, is recommended for Hepatology specialists. This medical degree should take about four more years of study. During the first two years of medical school, the student’s will expand further their knowledge in biology, anatomy, physiology, chemistry, and other necessary sciences that will support them for their next two years in medical school. The first two years usually ends with a test to gauge the student’s intellectual capability and their readiness to begin their practical work under direct supervision.
The last two years of medical school allows the student to apply the theories that they have learned during the first two years. They will begin rotations under direct supervision and they will take part in patient care in different specialties and facilities. The core specialties for rotations include ambulatory medicine and emergency medicine, gynecology and obstetrics, internal medicine, pediatrics, psychiatry, and surgery. The students will also have the opportunity to get an experience in their chosen specialty or sub-specialty by being involved in an elective rotation program. The fourth year of medical school ends with the second of three tests in the series to evaluate the student’s knowledge and skills as well as to determine if they are ready to proceed to a residency program where they will be more hands on and less supervised.
Residency
A Hepatology student must be able to complete and pass a two to four year residency in Gastroenterology, Hepatology, or internal medicine in general. The residency aims to provide the students with a chance to gain experience and broaden their knowledge to further specialize. This residency rotation will involve extensive laboratory work, where pathological testing methods and laboratory result interpretation techniques can be studied and applied under supervision. Laboratory training is important due to the fact that the abnormalities in laboratory tests are usually the only indicator of liver diseases. The patterns of the abnormality in the results are also indicative of the specificity of the disease and its underlying process.
Fellowship
Fellowship programs are the focused portion of education and training for those seeking the sub-specialty. Due to an overlap in their roots, the discipline of Hepatology is often combined with Gastroenterology. This means that, even though Hepatology is a free-standing specialty, aspiring Hepatologists complete a combined fellowship program from the field of Hepatology and Gastroenterology. the program includes an in depth discussion on the basics of the field, clinical manifestations, pathophysiology, management of disease, clinical procedures, and other topics that are focused on the organs included in Hepatology especially the liver.
In order to cater to the growing demand for Hepatology fellowships, some universities have begun offering a one to two year fellowship programs that are focused on Hepatology. This allows a physician from whatever background or specialty to gain knowledge about Hepatology.
Licensing and other Requirements
After the fellowship program, most aspiring hepatologists complete their board certification and follows the continuing education requirements in internal medicine. To become a certified internal medicine specialist in the United States, a physician should complete and pass both the Pre-doctoral and Graduate Medical Education requirements. the physician must also pass the Internal Medicine Certification Examination of the American Board of Internal Medicine (ABIM).
Continuing education on the field in forms of seminars, fellowships, etc. must also be acquired in order to ensure that the specialists are up-to-date with the new researches and technology in their field.
Roles and Responsibilities
Hepatologists are expected to be more direct in patient care compared to some of the other medical specialties. The most frequent diseases that hepatologists deal with are viral hepatitis and diseases related to alcohol use or abuse. Hepatology patients are often referred to by General Practitioners or by physicians from other disciplines. The specialists in this field can treat both adult and pediatricpatients. The involvement of a hepatologist can be due to (but not limited to):
Hepatologists may also conduct follow-up among patients that have undergone a liver transplant surgery to make sure that the new organ is accepted by the body and that this organ is functioning normally. They may also conduct consultations for patient who have developed liver disease because of their treatments or medications.
Given that laboratory abnormalities are usually the only indicator of liver disease; hepatologists are required to be able to perform diagnostic procedures. These procedures include the use of endoscopic retrograde cholangiopancreatography (ERCP), which is used to diagnose and treat many biliary and pancreatic diseases, and transhepaticpancreato-chloangiography, which is an X-ray used to locate obstruction/s in the bile ducts or liver. Hepatologists are also required to perform surgeries like transjugular intrahepatic portosystemic shunt which is an artificial channel made to connect the portal and hepatic veins. The purpose of these surgeries is mainly to treat or prevent complications that resulted from liver diseases.
Aside from patient care, hepatologists may also be a pioneer or be part of a research study in their specific field. These studies may provide new insights to Hepatology or create new diagnostic methods in assessing diseases. These may also give birth to new therapeutic approaches to the disease for better prevention or treatment.
Salary
Hepatologists are one of the highest paid medical careers below only orthopedics, cardiology, and urology in terms of salary and benefits. In terms of compensation, hepatologists are expected to receive the same amount as that of Gastroenterologists and other specialists in thefield.
According to MedScape, the average salary of hepatologists in the United States ranges from $150,000 to $382,000 per year. The average annual salary for this profession is estimated to be $348,000. The Great Lakes region holds the highest average salary of around $382,000 per year in the United States while the mid-Atlantic region has an average of $63,000 lower, which is considered as the lowest average salary in the country.
In the case of self-employed physicians, the average salary is $95,000 higher than those who are employed by a hospital or those who are in other practice. In the practice setting, the average compensation are as follow:
History
Even though Hepatology is a relatively new free-standing specialty, liver damage has been known to exist since ancient times. Anthropologists have found evidence of liver damage from the Egyptian mummies. The damaged that was seen through the autopsies is believed to be caused by a widespread parasitic infection known as Bilharziasis. Parts of the Greek mythological story "Prometheus" also suggests that the Greeks may have been aware of the liver's ability to exponentially duplicate. However, the knowledge of the ancient society as well as their ability to respond to liver disease is still questionable due to the fact that most of the important advances on the study of the liver, it's related organs, and the diseases that affects them have only been made in the last 50 years.
It has been recorded in 400 B.C. that Hippocrates has described liver abscess. The Roman anatomist Galen considered the liver to be the most important organ in the body and he also identified the relationship of the liver, the gallbladder, and the spleen. Around 100 C.E. a celebrated Greek physician named Areteusfrom Cappadocia made a significant contribution in the diagnosis or liver disease by describing jaundice and its symptoms. Furthermore, in the medieval times Avicenna observed the significance of urine in the diagnosis of liver disease.
In 1770, a French anatomist named Antoine Portal noted the bleeding that occurs due to the presence of esophageal varices caused by portal hypertension in cirrhosis patients. 1844 marked the year that the role of the pancreatic enzymes in breaking down food during digestion was discovered by Gabriel Valentin. Valentin's discovery was followed by Justus Von Leibig's discovery of the pancreatic juice tyrosine in 1846 and Austin Flint's description of the production of stercorin.
In 1958, Francis Moore developed and performed the first series of liver transplants on dog experimental models. It took more than five years for the liver transplant procedures to be deemed suitable for human application. In 1963, the first human liver transplant was performed by Dr. Thomas E. Starzi on a three year old male who had biliary atresia.
A new perspective on liver diseases emerged when an American physician and geneticist named Baruch S. Blumberg discovered the Hepatitis B virus and its mechanisms. He later linked this virus to liver cancer. Blumberg, along with his team, later developed a screening test and developed the first vaccine against the virus. He freely distributed the vaccine patent to promote its distribution by the drug companies which reduced the infection rate of hepatitis B in children in China from 15% to 1% in 10 years. In 1976, he received the Nobel Prize in Physiology or Medicine for "discoveries concerning new mechanisms for the origin and dissemination of infectious diseases".
During the mid-1970's, Harvey J. Alter, along with his research team from the Infectious Disease Section of the Department of Transfusion Medicine at the National Institutes of Health, observed post-transfusion hepatitis cases that were not caused by hepatitis A or hepatitis B. The virus was then called non-non-B hepatitis (NANBH) but further efforts to identify the virus have failed for the next decade. In 1987, investigators from the Center for Disease Control and Prevention (CDC) and Chiron Corporation, led by Daniel Bradley and Michael Houghton from the respective institutions, used a novel molecular cloning approach to identify the unknown organism and develop a diagnostic test for it. The result of their study wasconfirmed by Alter in 1988 and the virus was named Hepatitis C virus (HCV). The discovery of HCV was later published in two articles in the Journal of Science on April 1989 and significant improvements in diagnosis and antiviral treatments were made.
Liver Pathology and Common Diseases
The liver is an integral part of the body. It is one of the largest organs of the body (second only to the skin) and it is the largest internal organ with an average weight of 1493.79 grams. It is responsible for removing waste materials in the blood, producing enzymes and bile for food digestion, and converting food into an easily absorbable material for the body. With overeating and an unhealthy lifestyle, liver diseases have been rampant in the present society. It is estimated that around 25 million Americans have been afflicted with liver disease and have experienced its complications or even death. Hepatologists spend a great deal of time focusing on the liver due to its vital role in the body and due to the fact that it is susceptible from diseases. This organ should also be monitored for its efficiency in taking part in metabolism and helping out in the body's immune system. Diseases and complications related to alcohol overconsumption and viral hepatitis are the usual cases that a hepatologist will have to deal with.
Liver disease is normally detected through laboratory tests and often times, abnormalities in the results of these tests are the first and only sign that there is an underlying disease. The pattern of abnormality in the laboratory test results is often indicative of the underlying disease process and its severity. Four general patterns are apparent when assessing and testing liver function. These four patterns are:
Ascites or the accumulation within the abdomen of the protein-containing fluid is often associated to cirrhosis. Both transudative ascites, having 3 grams or less of protein per 100 mL of fluid, and exudative ascites, having 3 grams or more of protein per 100 mL of fluid, may occur and differentiating between those two requires a determination of gradient. Transudative ascites has a high gradient (>1.1g/dL) and is often seen in patients with cirrhosis, alcoholic hepatitis, or congestive heart failure while exudative ascites has a low gradient (<1.1g/dL) and is seen in patients with peritoneal carcinomatosis or tuberculosis.
Diseases and complications related to alcohol overconsumption and viral hepatitis are the usual cases that a hepatologist will have to deal with.
Alcohol-Related Liver Disease
Alcholol-Related Liver Disease or Alcoholic Liver Disease (ALD) is one of the leading causes of death worldwide. ALD is the general term for the diseases of the liver that are caused by the overconsumption of alcohol. The liver can only process alcohol in small doses so prolonged alcohol overconsumption causes a variety of liver manifestations including fatty liver, chronic hepatitis, and alcoholic hepatitis. Tissue scarring is often evident in the diseased liver and cirrhosis, the replacement of normal liver tissue by scar tissue, marks the final stage of ALD. Even though ALD does not occur in all heavy drinkers, the chances of having this disease increases the longer a person has been drinking and as they drink more alcohol.
The severity of the symptoms usually progresses slowly depending on how well the liver is working but there are times when there are no symptoms at all. Early symptoms of ALD include:
As the disease progresses, the symptoms may include:
To test for ALD, the physician or healthcare provider will do a physical exam to look for an enlarged liver or spleen, excess breast tissue, swollen abdomen due to ascites, reddened palms, red-spider like blood vessels on the skin, small testicles, widened veins in the abdomen wall, and jaundice. The laboratory tests to confirm ALD and rule out other diseases include a complete blood count (CBC), liver biopsy, liver function test, coagulation studies, abdominal CT scan, blood tests for other causes of liver disease, and abdominal ultrasound.
Refraining from drinking alcohol and having a healthy diet can help slow down the spread of the disease and getting vaccinated for diseases such as influenza, hepatitis A, hepatitis B, and pneumococcal pneumonia will also help the patient avoid further contracting these diseases. The patient with ALD or suspected ALD should always consult their doctor for recommended medications and supplements. For advance stages of the disease the patient might need to undergo the following treatments:
Viral Hepatitis
Viral hepatitis is the term used for the viral disease that causes inflammation of the liver cells and damage to the liver. The liver is an important organ that is responsible for filtering the blood, processing nutrients, and fighting infections. By causing inflammation and liver damage, hepatitis impairs the liver and creates severe health problems throughout the body.
While this disease can be caused by alcohol overconsumption, toxins, some drugs, and certain medical conditions, it is most often caused by a virus.Viral hepatitis inflicts and kills thousands of people every year in the United States alone. This disease causes more deaths than Human Immunodeficiency Virus (HIV), malaria, and tuberculosis. This disease has risen in global importance since the 1990’s and it still ranks among the leading infectious diseases today. There are at least five types of viruses that cause hepatitis and their symptoms can be similar.The three most common types of this disease are hepatitis A, B, and C.Each type is caused by a different virus and all of the three types can be acute, lasting for six months or less, and types B and C can chronic and last longer.
Among the three, hepatitis A is mild and easy to recover from. A person who has contracted and recovered from hepatitis A will develop immunity and protection from the virus. However, if left untreated, the symptoms of this virus can be severe and life threatening. This type is contracted by people in parts of the world with poor sanitation.
Hepatitis B, on the other hand, is a more severe form of hepatitis. It can be transmitted through unprotected sex with an infected person, needle sharing, personal items sharing (i.e. toothbrush or razor), or transfer of body fluid from an infected person. This type of hepatitis can cause severe liver damage by causing the liver to swell. It can also lead to chronic complications including cirrhosis and a type of cancer known as hepatocellular carcinoma. Currently, there is no cure for HBV but there is an available vaccine for both HAV and HBV.
Hepatitis C is considered as the most severe among the three. One out of four people with this disease develop cirrhosis that can lead to liver cancer. Similar to HBV, this disease can be transferred through body fluids especially blood. Children who are born to mothers who have contracted this disease are also at-risk. There is no available vaccine for this disease, but it can be cured through treatment. Sadly, 70 to 80 percent of people who have HCV carry this disease throughout their lifetime.
Hepatitis symptoms are often mild or unnoticeable in its early stages. After between 15-180 days, the symptoms of the disease are more noticeable. This period is considered as the start of the acute phase. The symptoms are almost similar to mild flu, this may include:
The acute phase is often mild and easy to treat but if left untreated, this may progress to acute liver failure and death. In the case of HBV and HCV, this symptoms can progress to a chronic infection.
Chronic hepatitis can lead to advanced jaundice, progressive liver failure, ascites, swelling of the lower extremities, and internal bleeding. Symptoms of chronic or end-stage infection are:
Due to the similarity of symptoms of the three types of hepatitis, determining the diagnosis and treatment for it is a bit tricky. The type and severity of the disease may only be diagnosed through extensive laboratory tests. These tests may include blood tests, nucleic acid tests, liver biopsy, surrogate marker test, paracentesis, and elastography of the liver.
The treatment will be based on the results of the laboratory tests. For patients with HAV, the doctor may advise the patient to abstain from alcohol or drugs during the recovery period. A patient with HAV usually recovers without intervention. Patients with HBV will be required to rest and completely abstain from alcohol. Antiviral agent called interferon and antiviral suppressive therapies may also be prescribed depending on the severity of the infection.
Antiviral agents (with or without ribavirin) will be prescribed to HCV patients to treat or slow down the infection. Directed antivirals and combination therapies depending on the virus subtype are also available. These treatments are often expensive but when taken correctly, the cure rate of these treatments are very high.
References
How to become a Hepatologist.(n.d.). Retrieved December 12, 2017, from http://doctorly.org/how-to-become-a-hepatologist/
Strom, B. L., MD, MPH. (2017, December). HBV: An underprioritizedpublic health threat. Retrieved December 18, 2017, from https://www.healio.com/infectious-disease/vaccine-preventable-diseases/news/print/infectious-disease-news/%7b320ba1bd-7d5e-4868-84d7-566fff85d8b4%7d/hbv-an-underprioritized-public-health-threat
Boyer, JL (2001). Liver cirrhosis and its development: proceedings of the Falk Symposium 115. Springer.pp. 344.ISBN 978-0-7923-8760-2.
Nordqvist, C. (2017, November 24). Viral hepatitis: Types, symptoms, treatment, and prevention. Retrieved December 17, 2017, from https://www.medicalnewstoday.com/articles/145869.php
Alcoholic liver disease.(n.d.). Retrieved December 20, 2017, from https://medlineplus.gov/ency/article/000281.htm
PhD, C. P. (2016, July 07). Viral hepatitis has become a leading global killer. Retrieved December 10, 2017, from https://www.medicalnewstoday.com/articles/311505.php
Wu, B. (n.d.). Alcoholic Hepatitis: Symptoms, Treatment, and Outlook. Retrieved December 10, 2017, from https://www.medicalnewstoday.com/articles/313928.php
Robertson, S., BSc. (2014, November 19). What is Hepatology? Retrieved December 07, 2017, from https://www.news-medical.net/health/What-is-Hepatology.aspx