Acute Liver Failure

Split liver transplants could safely help sickest children: Analysis of donors, recipients and surgical approaches reveals optimal combinations

Acute Liver Failure | Johns Hopkins Medicine

In a review of registry data for more than 5,300 liver transplants performed in children nationwide, Johns Hopkins Medicine researchers identify the type of patient who is most ly to survive a split liver transplant — receiving only part of a donor's liver — with no additional long-term health risks, which could allow for an increase in the availability of organs. A report on the new study is published in the December issue of the journal Liver Transplantation.

“Kids dying while on the waitlist is the worst possible outcome,” says Douglas Mogul, M.D., Ph.D., medical director of the Pediatric Liver Transplant Program at Johns Hopkins Children Center and assistant professor of pediatric gastroenterology, hepatology and nutrition at the Johns Hopkins University School of Medicine.

Split liver transplants have been performed for nearly 30 years, according to Mogul, and using the liver's natural structure, a split liver transplant can use a 35 to 40 percent section, making split liver transplant ideal for children whose smaller weights accommodate smaller livers. “An SLT essentially could allow two transplants from a single liver,” says Mogul.

Using data from the Scientific Registry of Transplant Recipients, Mogul, colleague Dorry Segev, M.D., professor of surgery at the Johns Hopkins University School of Medicine, and their teams examined the medical records of 5,345 pediatric patients who had received their first — either split or whole — liver transplant in the United States between March 2002 and December 2015.

“We already knew from previous studies that variables including the donor's age and cause of death along with the health of the recipient can influence outcomes,” says Mogul.

“But understanding which of these variables could impact the outcomes from transplanting a split liver versus a whole liver could help guide the increased use of split livers and identify which patients will do best after split or whole liver transplants, thereby being more strategic about matching donor organs with recipients.”

Using a statistical analysis that relates variables with an event or outcome, the team looked at the relationship between the type of liver — split or whole — and transplant success after adjusting a number of variables, including many that had previously been reported as influencing organ transplant success. Those variables included organ donor age, cause of death, recipient weight at transplant, underlying disease and how sick the recipient is.

Of the 5,345 pediatric liver recipient records examined, 1,694 or roughly 31 percent received a split liver while 3,651 or roughly 68 percent received a whole liver.

Split liver recipients were less ly than whole liver recipients to receive an organ from another pediatric patient, 59 percent versus 83 percent, respectively, and more ly to have received their liver from a donor between ages 18 and 50, 38 percent versus 13 percent, respectively.

Split liver recipients were less ly than whole liver recipients to have a donor who suffered from lack of oxygen, but more ly to have a donor with head trauma.

On the surface, it appears that split liver transplants fared worse.

However, after adjusting the data for donor age, recipient weight, other recipient health problems as well as surgical approach, there was no difference in outcomes for split versus whole liver recipients.

More importantly, what the team found was that groups defined by certain characteristics that had the highest overall transplant failure were actually not further negatively impacted by having a split versus whole liver, implying that these sickest children would be good candidates for split livers. “One might anticipate that patients with the highest lihood of graft failure would do worse if they got a split compared to a whole. But we saw the opposite: These people were not further impacted by getting a split,” says Mogul.

Recipients who weighed less than 10 kilograms had higher rates of transplant failures in general, regardless of whether they received split or whole livers; suggesting that body weight less than 10 kilograms may be a factor for considering split liver transplantation.

In contrast, recipients who weighed between 10 and 35 kilograms had an overall lower risk of transplant failure, but the failure rate after receiving a split liver was 1.

46 times that of receiving a whole liver, suggesting recipients in this weight range should be considered for whole livers.

Overall, Mogul says, waiting children with lower body weights, who were in relatively worse health and whose donor livers spent more time on ice or in transit, had the same potential for a successful transplant with a split liver as they would have with a whole liver. The researchers estimate that 22 children on the liver transplant list could have benefited from split liver transplant but instead died while waiting.

“We hope these findings can help guide surgical decision-making and support policy changes that promote the increased use of SLT for selected children,” says Mogul. From their study, optimal recipients could include children weighing under 10 kilograms, with a rare disease of the bile ducts known as biliary atresia, acute hepatic necrosis or sudden liver death, autoimmune disease and tumor.

“The better understanding of SLT learned from this study and our most recent research is a critical step toward the goal of significantly increasing access to transplantation,” says Segev.

“If they wanted to, UNOS — the United Network for Organ Sharing, the entity responsible for U.S.

organ allocation policies — could institute policies within one to two years that would have huge impacts on children waiting for liver transplants.”

Story Source:

Materials provided by Johns Hopkins Medicine. Note: Content may be edited for style and length.

Source: https://www.sciencedaily.com/releases/2018/12/181219124246.htm

Liver function

Acute Liver Failure | Johns Hopkins Medicine

  • Multiple serum chemistries assayed to assess hepatic function and/or injury.
  • Tests indicative of: 1) liver inflammation: ALT (alanine aminotransferase) and AST (aspartate aminotransferase); 2) cholestasis or biliary obstruction: bilirubin (total includes both direct and indirect bilirubin), ALP (alkaline phosphatase) and GGT (gamma-glutamyltransferase); and 3) synthetic function: albumin and PT (prothrombin time).
  • Abnormal liver function due to non-alcoholic fatty liver disease (NAFLD) is common in diabetes.
  • Recently, combined patented algorithms (Fibrotest [FibroSURE in the U.S.]) have been made commercially available. Used to assess the presence of liver fibrosis.
  • Serum ALT, AST, ALP and bilirubin (total and direct) are measured indirectly by using a spectrophotometer.
  • PT, reported as the INR, measured from citrated whole blood: 1 full blue top, mixed gently. The vacutainer must be filled to the tube’s drawing capacity to achieve the proper blood to anticoagulant ratio.
  • Symptoms suggestive of liver disease: jaundice, dark urine, or light-colored bowel movements, loss of appetite, fatigue, vomiting of blood, bloody or black bowel movements, swelling or pain in the abdomen, unusual weight changes.
  • Signs suggestive of liver disease: hepatomegaly, ascites
  • Exposure to medications associated with liver damage (e.g. HMG Co-A reductase inhibitors, thiazolidinediones), contact with people that have viral hepatitis, excessive alcohol consumption.
  • Presence of additional comorbid conditions associated with liver disease among persons with diabetes: extreme obesity, hypertriglyceridemia, alcohol use
  • To monitor response to treatment or track course of disease in patients with liver disease.
  • Increased AST: primary liver disease, acute myocardial infarction, muscle trauma and diseases, pancreatitis, intestinal surgery, burns, renal infarction, pulmonary embolism.
  • Increased ALT: primary liver disease, biliary obstruction, pancreatitis. ALT > AST viral hepatitis, AST> ALT alcoholic liver disease.
  • Increased ALP: biliary obstruction, primary liver disease (changes parallel GGT), infiltrative liver disease, bone diseases, hyperparathyroidism, hyperthyroidism.
  • Increased GGT: biliary obstruction, primary liver disease (changes parallel ALP), alcohol consumption, pancreatitis
  • Increased bilirubin: biliary obstruction, primary liver disease, hemolytic anemias, hypothyroidism
  • Medications: may cause increases in one or more liver chemistry tests because of direct hepatotoxicity or cholestasis (See American Gastroenterological Association (AGA) Technical Review[1] for full list of medications).
  • ALT and AST are abundant liver enzymes. AST is also present in heart, muscle. ALP is present in nearly all tissues, primarily bone and liver. GGT is abundant in liver, kidney, pancreas and intestine.
  • ALT and AST normal ranges vary depending on lab, in general: ≤ 40 U/L.
  • Mild ALT and AST elevations (ALT and AST less than 5 times the upper limit of normal (ULN)) should be rechecked before extensive work-up is undertaken. Possible causes: chronic hepatitis C or B, acute viral hepatitis, NAFLD, hemachromatosis, autoimmune hepatitis, medications, alcohol-related liver injury, Wilson’s disease.
  • Moderately elevated ALT and AST (ALT and AST 5-15 times the ULN) should be investigated without waiting to confirm the persistence of abnormal ALT, possible causes: entire spectrum of liver diseases that may cause either mild or severe elevations.
  • Severe ALT and AST elevations (ALT and AST greater than 15 times the ULN) suggest severe acute liver cell injury: acute viral hepatitis, ischemic hepatitis or other vascular disorder, toxin-mediated hepatitis, acute autoimmune hepatitis.
  • Bilirubin is a heme degradation product excreted in the bile, it requires conjugation in the liver before its secretion.
  • Hyperbilirubinemia: Investigate if caused by direct (conjugated) or indirect (unconjugated) fraction of bilirubin. Pre-hepatic causes (increased production, decreased liver uptake) cause increase of indirect. Intra-hepatic or post-hepatic causes (decreased hepatic excretion), increase of direct. Increased production: hemolysis. Decreased liver uptake: Gilbert Syndrome, found in 5% population, benign. Decreased hepatic excretion: bile duct obstruction, primary biliar cirrhosis, primary sclerosing cholangitis, benign recurrent cholestasis, hepatitis, cirrhosis, medications, sepsis, total parenteral nutrition, Dubin-Johnson Syndrome, medications (See AGA Technical Review[1] for full list of medications).
  • Increased GGT: Alcohol consumption
  • Increased ALP and GGT: bile duct obstruction, primary biliary cirrhosis, primary sclerosing cholangitis, benign recurrent cholestasis, infiltrative disease of the liver (sarcoidosis, lymphoma, metastasic disease)
  • Isolated elevated ALP (extra-hepatic disease): bone disease, pregnancy, chronic renal failure, lymphoma, congestive heart failure.
  • Abnormal PT (expressed in seconds or as INR) and albumin levels: indicate severe hepatic synthetic dysfunction and indicates progression to cirrhosis or impending hepatic failure.
  • Other commonly used tests to assess potential causes of hepatic diseases include: viral markers (IgM Hepatitis A Virus, HBsAg, Total Anti-HBc, IgM anti-HBc, anti-hepatitis C antibody), immunologic markers (ANA, SMA, anti-LKM-1, AMA), genetic diseases (hereditary hemochromatosis: transferrin saturation, ferritin, hepatic iron index; Wilson’s disease: serum ceruloplasmin, urinary copper; a1-antitrypsin deficiency: serum electrophoresis), hepatocellular carcinoma marker (AFP: alfa-Fetoprotein) and imaging studies (ultrasound, CT, MRI).
  • Poor correlation between ALT and AST levels and hepatic fibrosis. Patients with cirrhosis may have normal or only mildly elevated ALT.
  • For ALT, AST, ALP and bilirubin samples, hemolysis can cause significant increases. Samples need to be stable at 0 to 4 ° C over 1 to 3 days.
  • ALT and AST: increase with strenuous exercise and muscle injury. Meals have no effect. ALT is increased with higher BMI.
  • ALP levels increase with food intake, pregnancy and smoking.
  • Bilirubin levels increase with fasting. Light exposure decrease bilirubin.
  • Among people with type 2 diabetes (T2DM), liver disease is one of the leading causes of death.
  • In addition, patients with T2DM have have a higher incidence and prevalence not only of NAFLD, but of hepatitis C and hepatocellular carcinoma compared to the general population.
  • Liver tests are not always specific for the liver because there are extra-hepatic sources.
  • Normal levels of liver chemistry tests (including ALT) do not exclude the presence of disease.
  1. Green RM, Flamm S. AGA technical review on the evaluation of liver chemistry tests. Gastroenterology. 2002;123(4):1367-84.  [PMID:12360498]

    Comment: Formal recommendations on how to interpret liver function tests and comprehensive list of medications that may cause liver toxicity or injury. http://www.gastro.org

  1. Dufour DR, Lott JA, Nolte FS, et al. Diagnosis and monitoring of hepatic injury. I. Performance characteristics of laboratory tests. Clin Chem. 2000;46(12):2027-49.

     [PMID:11106349]

    Comment: Very detailed review of the characteristics of all liver tests, reference values, individual factors influencing their levels.

    An approved guideline not only by the National Academy of Clinical Biochemistry but also by the American Association for the Study of Liver Diseases.

  2. Dufour DR, Lott JA, Nolte FS, et al. Diagnosis and monitoring of hepatic injury. II. Recommendations for use of laboratory tests in screening, diagnosis, and monitoring. Clin Chem. 2000;46(12):2050-68.  [PMID:11106350]

    Comment: Detailed review of the different patterns of liver injuries and their laboratory findings. An approved guideline by the National Academy of Clinical Biochemistry

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Acute Liver Failure

Acute Liver Failure | Johns Hopkins Medicine

Acute liver failure is a rare condition. It happens when your liver suddenly begins to lose its ability to function. This often happens right after an overdose of medicine or poisoning. Chronic liver failure happens over a long stretch of time.

What causes acute liver failure?

Acute liver failure can be caused by hepatitis. It can also be caused by taking medicines such as acetaminophen. Autoimmune disease and Wilson’s disease can also cause acute liver failure. In some cases, the cause for the disease is unknown.

Who is at risk for acute liver failure?

Taking too much acetaminophen causes most cases of acute liver failure. Acetaminophen is a painkiller found in many over-the-counter and prescription medicines. There are also other things that can lead to acute liver failure. Diseases such as hepatitis and Wilson’s disease, cytomegalovirus, Epstein-Barr virus, and herpes simplex virus also increase your risk for acute liver failure.

What are the symptoms of acute liver failure?

If you have acute liver failure, you may have symptoms such as:

  • Diarrhea
  • Discomfort on your right side, just below your ribs
  • Fatigue
  • Loss of appetite
  • Nausea

As the disease gets worse, however, you may also become confused and extremely sleepy. Other symptoms include bruising or bleeding easily, vomiting blood, and a buildup of fluid in your abdomen.

How is acute liver failure diagnosed?

Liver failure is a serious condition that requires immediate medical attention. Your healthcare provider will probably do an evaluation to find out if you have a history of drug use, exposure to toxins, and to check for signs of hepatitis.

These signs include jaundice, fatigue, and abdominal pain. Your healthcare provider will also test your mental alertness. He or she may also do blood tests. These tests will check your liver enzymes, bilirubin levels, and prothrombin time.

Prothrombin time measures your blood’s ability to thicken (coagulate).

How is acute liver failure treated?

Treatment for acute liver failure depends on the underlying cause. If your healthcare provider thinks you took too much acetaminophen within the past several hours, you will probably be given activated charcoal.

Taking this will help your body reduce how much medicine is absorbed in your gastrointestinal tract. N-acetylcysteine is another drug that can help with an acetaminophen overdose. You can take this medicine either by mouth or through your vein.

N-acetylcysteine is also sometimes helpful to people with acute liver failure that was not caused by too much acetaminophen.

If viral hepatitis is the cause of your acute liver failure, your healthcare provider may give you a medicine depending on the type of viral hepatitis that is causing the failure. If autoimmune hepatitis is causing your liver failure, your healthcare provider can treat you with steroids.

If your healthcare provider can’t find the cause of your acute liver failure, you may need a liver biopsy. This will give more information and help determine your course of treatment.

If treatment can’t get your liver working again, you may need a liver transplant. Good candidates for transplant are strong enough for surgery. They don’t have underlying cardiovascular disease, severe infection, or other diseases, AIDS.

However, people with controlled HIV can get a liver transplant. If you are approved for a liver transplant, your name will be put on a waiting list to get a donated organ. People with the most urgent need are placed at the top of the list.

While you are waiting for a liver to become available, you may be able to have some therapies to keep you alive. However, the effectiveness of these treatments is unclear.

What are the complications of acute liver failure?

If you have acute liver failure, common complications include bacterial and fungal infection and low blood sugar. Swelling of the brain is another side effect of acute liver failure. It is also one of the most serious. Confusion, abdominal swelling, and abnormal bleeding are also common.

Can acute liver failure be prevented?

You can prevent some of the underlying causes of acute liver failure. To avoid acetaminophen overdose, always follow the directions on the label when taking a drug that contains acetaminophen. Talk with your pharmacist or healthcare provider if you have any questions.

You can reduce your risk of getting viral hepatitis by avoiding contact with the blood or feces of an infected person. If you visit other countries, particularly developing nations, you should avoid the local tap water. Vaccines are available to prevent hepatitis A and B.

When should I call my health care provider?

Acute liver failure can happen in as little as 48 hours. It’s important to seek medical treatment at the first signs of trouble. These signs may include fatigue, nausea, diarrhea, and discomfort in your right side, just below your ribs.

Key points about acute liver failure

  • Acute liver failure happens when your liver suddenly begins to lose its ability to function
  • An overdose of acetaminophen is the most common cause of acute liver failure
  • Acute liver failure causes fatigue, nausea, loss of appetite, discomfort on your right side, just below your ribs, and diarrhea
  • Acute liver failure is a serious condition that requires immediate medical attention
  • If medical treatments are not effective, you may be a candidate for a liver transplant

Source: https://www.hopkinsmedicine.org/health/conditions-and-diseases/acute-liver-failure

Common Characteristics of Liver Disease

Acute Liver Failure | Johns Hopkins Medicine

Linkedin Pinterest Liver Gallbladder and Pancreas

When diagnosing liver disease, the doctor looks at the patient's symptoms and conducts a physical examination. In addition, the doctor may request a liver biopsy, liver function tests, an ultrasound, a computed tomography (CT) scan, and/or a magnetic resonance imaging (MRI) scan.

Some common liver disease symptoms include the following, each of which are described briefly below:

  • Jaundice. A yellowing of the skin and eyes.
  • Cholestasis
  • Liver enlargement
  • Portal hypertension
  • Esophageal varices
  • Ascites. A fluid buildup in the abdominal cavity.
  • Liver encephalopathy
  • Liver failure

What is jaundice?

Jaundice is a yellow discoloration of the skin and whites of the eyes due to abnormally high levels of bilirubin (bile pigment) in the bloodstream. Urine is usually dark because of the bilirubin excreted through the kidneys.

High levels of bilirubin may be attributed to inflammation, or other abnormalities of the liver cells, or blockage of the bile ducts. Sometimes, jaundice is caused by the breakdown of a large number of red blood cells, which can occur in newborns.

Jaundice is usually the first sign, and sometimes the only sign, of liver disease.

What is cholestasis?

Cholestasis means any condition in which bile flow is reduced or stopped. “Chole” refers to bile and “stasis” means “not moving.” Bile flow may be blocked inside the liver, outside the liver, or in both places. Symptoms may include:

  • Jaundice
  • Dark urine
  • Pale stool
  • Easy bleeding
  • Itching
  • Ascites
  • Chills
  • Pain from the biliary tract or pancreas
  • Enlarged gallbladder

Some causes of cholestasis include the following:

  • Hepatitis
  • Alcoholic liver disease
  • Primary biliary cirrhosis
  • Drug effects
  • Hormonal changes during pregnancy
  • A stone in the bile duct
  • Bile duct narrowing
  • Bile duct cancer
  • Pancreatic cancer
  • Inflammation of the pancreas

What is liver enlargement?

Liver enlargement is usually an indicator of liver disease, although there are usually no symptoms associated with a slightly enlarged liver (hepatomegaly). Symptoms of a grossly enlarged liver include abdominal discomfort or “feeling full.”

What is portal hypertension?

Portal hypertension is high blood pressure in the portal vein, which supplies the liver with blood from the intestine and spleen. Portal hypertension may be due to increased blood pressure in the portal blood vessels, or resistance to blood flow through the liver.

Portal hypertension can lead to the growth of new blood vessels (called collaterals) that connect blood flow from the intestine to the general circulation, bypassing the liver. When this occurs, substances that are normally removed by the liver pass into the general circulation.

Symptoms of portal hypertension may include:

  • Ascites
  • Development of varicose veins. Varicose veins (esophageal varices) develop most commonly at the lower end of the esophagus and in the stomach lining, although they can develop anywhere from the mouth to the anus.

What are esophageal varices?

Esophageal varices are dilated blood vessels within the walls of the lower part of the esophagus that are prone to bleeding. They can appear in people with severe liver disease.

A diseased liver can cause portal hypertension, which is high blood pressure in the portal vein. The portal vein supplies the liver with blood. Over time, this pressure causes blood vessels to grow, called collateral blood vessels.

These vessels act as channels to divert the blood under high pressure. The extra pressure in these vessels causes them to dilate and become tortuous. These vessels can eventually reach the lower esophagus and stomach and are prone to rupture.

The rupture can lead to significant blood loss from vomiting or from lost blood passing through the gastrointestinal tract. Symptoms of esophageal varices may include:

  • Painless vomiting of blood
  • Black, tarry or bloody stools
  • Decreased urine output
  • Excessive thirst
  • Light-headedness
  • Paleness
  • Anemia. A condition that indicates a low red blood cell count.

What is ascites?

Ascites is fluid buildup in the abdominal cavity caused by fluid leaks from the surface of the liver and intestine. Ascites due to liver disease usually accompanies other liver disease characteristics, such as portal hypertension. Symptoms of ascites may include a distended abdominal cavity, which causes discomfort and shortness of breath. Causes of ascites may include the following:

  • Liver cirrhosis (especially cirrhosis caused by alcoholism)
  • Alcoholic hepatitis
  • Obstruction of the hepatic vein

Ascites can also be caused by nonliver disorders.

What is liver encephalopathy?

Liver encephalopathy is the deterioration of brain function and damage to the nervous system due to toxic substances building up in the blood, which are normally removed by the liver. Liver encephalopathy is also called portal-systemic encephalopathy, hepatic encephalopathy, or hepatic coma. Symptoms may include:

  • Impaired consciousness
  • Changes in logical thinking, personality, and behavior
  • Mood changes
  • Impaired judgment
  • Drowsiness
  • Confusion
  • Sluggish speech and movement
  • Disorientation
  • Loss of consciousness
  • Coma
  • Seizures (rare)
  • Muscle stiffness or tremors
  • Uncontrollable movement

What is liver failure?

Liver failure is severe deterioration of liver function. Liver failure occurs when a large portion of the liver is damaged due to any type of liver disorder. Symptoms may include:

  • Jaundice
  • Tendency to bruise or bleed easily
  • Ascites
  • Impaired brain function
  • General failing health
  • Fatigue
  • Weakness
  • Nausea
  • Loss of appetite
  • Diarrhea

Source: https://www.hopkinsmedicine.org/health/conditions-and-diseases/common-characteristics-of-liver-disease

Liver: Function, Failure & Disease

Acute Liver Failure | Johns Hopkins Medicine

The liver is an abdominal glandular organ in the digestive system. It is located in the right upper quadrant of the abdomen, under the diaphragm and on top of the stomach. The liver is a vital organ that supports nearly every other organ to some capacity. 

The liver is the body's second-largest organ (skin is the largest organ), according to the American Liver Foundation (ALF), weighing about 3 lbs. (1.4 kilograms). At any given moment, the liver holds about 1 pint (half a liter) of blood — about 13 percent of the body's blood supply, according to Johns Hopkins Medicine. 

The liver is shaped a football, or a cone, and consists of two main lobes. Each lobe has eight segments that consist of 1,000 small lobes, or lobules, according to Johns Hopkins. The lobules are connected to ducts that transport bile to the gallbladder and small intestine.

Function

“The liver has a complex role in the function of the body,” said Jordan Knowlton, an advanced registered nurse practitioner at the University of Florida Health Shands Hospital. “Detoxification, metabolism (including regulation of glycogen storage), hormone regulation, protein synthesis, digestion, and decomposition of red blood cells, to name a few.” 

In fact, more than 500 vital functions have been identified with the liver, according to Johns Hopkins, including:

  • Production of bile, which helps carry away waste and break down fats in the small intestine during digestion.
  • Production of certain proteins for blood plasma. 
  • Production of cholesterol and special proteins to help carry fats through the body
  • Conversion of excess glucose into glycogen for storage (glycogen can later be converted back to glucose for energy) and to balance and make glucose as needed 
  • Regulation of blood levels of amino acids, which form the building blocks of proteins
  • Processing of hemoglobin for use of its iron content (the liver stores iron)
  • Conversion of poisonous ammonia to urea (urea is an end product of protein metabolism and is excreted in the urine)
  • Clearing the blood of drugs and other poisonous substances
  • Regulating blood clotting
  • Resisting infections by making immune factors and removing bacteria from the bloodstream
  • Clearance of bilirubin, also from red blood cells. If there is an accumulation of bilirubin, the skin and eyes turn yellow.  

Detoxification

One of the best-known roles of the liver is as a detoxification system. It removes toxic substances from blood, such as alcohol and drugs, according to the Canadian Liver Foundation. It also breaks down hemoglobin, insulin and excessive hormones to keep hormone levels in balance. Additionally, it destroys old blood cells. 

The liver is vital for healthy metabolic function.

It metabolizes carbohydrates, lipids and proteins into useful substances, such as glucose, cholesterol, phospholipids and lipoproteins that are used in various cells throughout the body, according to Colorado State University's Department of Biomedical Sciences' Hypertexts for Pathophysiology: Metabolic Functions of the Liver. The liver breaks down the unusable parts of proteins and converts them into ammonia, and eventually urea.

Liver disease

According to the Canadian Liver Foundation, there are more than 100 types of liver disease, and they are caused by a variety of factors, such as viruses, toxins, genetics, alcohol and unknown causes. The following are among the most common types of liver disease: 

  • Alagille syndrome
  • Alpha 1 anti-trypsin deficiency
  • Autoimmune hepatitis
  • Biliary atresia
  • Cirrhosis
  • Cystic disease of the liver
  • Fatty liver disease
  • Galactosemia
  • Gallstones
  • Gilbert's syndrome
  • Hemochromatosis
  • Liver cancer
  • Liver disease in pregnancy
  • Neonatal hepatitis
  • Primary biliary cirrhosis
  • Primary sclerosing cholangitis
  • Porphyria
  • Reye's syndrome
  • Sarcoidosis
  • Toxic hepatitis
  • Type 1 glycogen storage disease
  • Tyrosinemia
  • Viral hepatitis A, B, C
  • Wilson disease

According to the National Institutes of Health (NIH), one symptom of liver disease is jaundice — yellowish skin and eyes. Other symptoms include abdominal pain and swelling, persistent itchy skin, dark urine, pale stools, bloody or black stools, exhaustion, bruising easily, nausea and loss of appetite.

Fatty liver

There are two types of fatty liver, according to the Cleveland Clinic: that caused by excessive alcohol consumption (fatty liver) and that which is not (non-alcoholic fatty liver or non-alcoholic steatohepatitis). 

Speaking of both conditions, Knowlton said, “Some fat on the liver is normal, but when it starts to accumulate to greater than 5-10 percent, it can lead to permanent liver damage and cirrhosis.

” It also increases the chance of liver failure or liver cancer. Fatty liver “can be caused by genetics, obesity, diet, hepatitis, or alcohol abuse,” said Knowlton.

Other risk factors include rapid weight loss, diabetes, high cholesterol, or high trigycerides, according to the ALF. 

Some people may get fatty liver even if they don't have any risk factors. Up to 25 percent of the U.S.

population suffers from fatty liver disease, according to the University of Michigan Health System.

There are no medical treatments for fatty liver disease, though avoiding alcohol, eating a healthy diet, and exercising can help prevent or reverse fatty liver disease in its early stages.

Enlarged liver

According to the Mayo Clinic, an enlarged liver (or hepatomegaly) isn't a disease itself, but a sign of an underlying serious problem, such as liver disease, cancer or congestive heart failure.

There may be no symptoms of an enlarged liver, though if they are they are the same as the symptoms for liver disease. Normally, the liver cannot be felt unless you take a deep breath, but if it is enlarged, your doctor may be able to feel it, according to the NIH.

The doctor may then do scans, MRIs, or ultrasounds of the abdomen to determine if you have an enlarged liver. Treatment will involve addressing the underlying problem.

Liver pain

Liver pain is felt in the upper right area of the abdomen, just below the ribs. Usually, it is a dull, vague pain though it can sometimes be quite severe and may cause a backache. Sometimes people perceive it as pain in the right shoulder.

It is often confused with general abdominal pain, back pain or kidney pain, according to New Health Guide. It can be hard to pinpoint the exact location or cause of such pains, so it is important to see a doctor.

Doctors may do blood tests, ultrasounds or biopsies to determine the cause of pain.

Liver pain can be the result of a variety of causes. Some common causes are: ascites (fluid in the abdomen), cirrhosis, hepatitis, liver failure, enlarged liver, liver abscess, and liver tumors. 

Liver failure

Liver failure is an urgent, life-threatening medical condition. It means that the liver has lost or is losing all of its function. “Livers typically fail gradually,” said Knowlton, “but sometimes [it] can be rapid.

” Early symptoms of liver failure are general, making it difficult to know that the liver is failing. Knowlton said, “Symptoms of liver failure may include nausea, appetite changes, fatigue, diarrhea, jaundice, easy bleeding.

” As the condition worsens, she said symptoms might include “mental confusion and coma.”

“Typical causes of liver failure include Tylenol overdose, viruses, hepatitis B & C, cirrhosis, alcoholism, and some medications,” said Knowlton. Georgia's Emory Healthcare stated that there are two types of liver failure: chronic and acute.

Chronic liver failure is the most common type of liver failure. It is the result of malnutrition, disease and cirrhosis, and it can develop slowly over years. Acute liver failure is rarer, and it can come on suddenly.

Acute liver failure is usually the result of poisoning or a drug overdose.

Liver failure treatments depend on the case. Knowlton said, “Treatment options are mostly supportive (hospitalization and treatment until the liver recovers), but ultimately may require liver transplantation.”

Liver transplant

Donated livers can come from cadavers or living donors. In the case of living donors, the donor donates part of his or her liver to another person, according to the American College of Gastroenterology.

The liver can regrow itself, so both people should end up with healthy, functional livers.

According to the National Institute of Diabetes and Digestive and Kidney Diseases the most common reason adults get liver transplants is cirrhosis, though transplants can also be done for patients with various liver diseases or early stage liver cancer.

A liver transplant is a very serious surgery that may take up to 12 hours. According to the Mayo Clinic, there are several risks involved with liver transplants, including:

  • Bile duct complications, including leaks or shrinking
  • Bleeding
  • Blood clots
  • Failure of donated liver
  • Infection
  • Memory and thinking problems
  • Rejection of donated liver

If you have a liver transplant, you can expect to stay in the hospital for at least a week after the surgery, to get regular checkups for at least three months, and to take anti-rejection and other medications for the rest of your life. It will take six months to a year to feel fully healed from the surgery.

Liver transplant success depends on the individual case. Transplants from cadavers have a 72 percent success rate, meaning that 72 percent of liver transplant recipients lived for at least five years after the surgery. Transplants from living donors had a slightly higher success rate, at 78 percent, according to the Mayo Clinic.

Things that can harm the liver

While some liver diseases are genetic, others are caused by viruses or toxins, such as drugs and poisons.

Some risk factors, according to the Mayo Clinic, include drug or heavy alcohol consumption, having a blood transfusion before 1992, high levels of triglycerides in the blood, diabetes, obesity and being exposed to other people's blood and bodily fluids. This can happen from shared drug needles, unsanitary tattoo or body piercing needles, and unprotected sex.

Alcohol is big player in liver damage. It is believed that alcohol could possibly change the type of fungi living in the liver, leading to disease, according to a small study published May 22, 2017, in the Journal of Clinical Investigation. If this is true, it could lead to new treatment options.

The findings suggest that “we might be able to slow the progression of alcoholic liver disease by manipulating the balance of fungal species living in a patient's intestine,” study co-author Dr. Bernd Schnabl, an associate professor of gastroenterology at the University of California, San Diego School of Medicine, said in a statement.

[How Alcohol & Gut Fungus Team Up to Damage Your Liver]

Additional reporting by Alina Bradford, Live Science contributor.

Additional Resources

Source: https://www.livescience.com/44859-liver.html