Acute fatty liver of pregnancy is a rare condition and occurs in approximately one in 7,000 to one in 15,000 pregnancies. The mortality from acute fatty liver of pregnancy has been reduced significantly to 18%, and is now related primarily to complications, particularly DIC (Disseminated Intravascular Coagulation) and infections. After delivery, most mothers do well, as the stimulus for fatty acid overload is removed. The disease can recur in future pregnancies, with a calculated genetic chance of 25%; the actual rate is lower, however. Mortality of the foetus has also diminished significantly, but still remains 23%, and may be related to the need for premature delivery.

Acute fatty liver of pregnancy is best treated in a centre with expertise in hepatology, high-risk obstetrics, maternal-fetal medicine and neonatology. The physicians who treat this condition will often consult with experts in liver transplantation in severe cases. Admission to the intensive care unit is recommended.

Initial treatment involves supportive management with intravenous fluids, intravenous glucose and blood products, including fresh frozen plasma and cryoprecipitate to correct DIC. The foetus should be monitored with cardiotocography. After the mother is stabilized, arrangements are usually made for delivery. This may occur vaginally, but, in cases of severe bleeding or compromise of the mother's status, a caesarian section may be needed. Often AFLP is not diagnosed until the mother and baby are in trouble, so it is most likely that an emergency C-section is needed.

The complications of acute fatty liver of pregnancy may require treatment after delivery, especially if pancreatitis occurs. Liver transplantation is rarely required for treatment of the condition, but may be needed for mothers with severe DIC, those with rupture of the liver, or those with severe encephalopathy.

Clinical practice guidelines by the American College of Gastroenterology have recommended corticosteroid treatment. Patients should be risk stratified using a MELD Score or Child-Pugh score.

- Corticosteroids: These guidelines suggest that patients with a modified Maddrey's discriminant function score > 32 or hepatic encephalopathy should be considered for treatment with prednisolone 40 mg daily for four weeks followed by a taper. Models such as the Lille Model can be used to monitor for improvement or to consider alternative treatment.

- Pentoxifylline: A randomized controlled trial found that among patients with a discriminant function score > 32 and at least one of the following symptoms (a palpable, tender enlarged liver, fever, high white blood cell count, hepatic encephalopathy, or hepatic systolic bruit), 4.6 patients must be treated with pentoxifylline for 4 weeks to prevent one patient from dying. Subsequent trials have suggested that pentoxifylline may be superior to prednisolone in the management of acute alcoholic hepatitis with discriminant function score >32. Advantage of pentoxifylline over prednisolone was better tolerability, lesser side effects, with decreased occurrence of renal dysfunction in patients receiving pentoxifylline.

- Potential for combined therapy: A large prospective study of over 1000 patients investigated whether prednisolone and pentoxifylline produced benefits when used alone or in combination. Pentoxifylline did not improve survival alone or in combination. Prednisolone gave a small reduction in mortality at 28 days but this did not reach significance, and there were no improvements in outcomes at 90 days or 1 year.

Anti-viral medications are available to treat infections such as hepatitis B. Other conditions may be managed by slowing down disease progression, for example:

- By using steroid-based drugs in autoimmune hepatitis.

- Regularly removing a quantity of blood from a vein (venesection) in the iron overload condition, hemochromatosis.

- Wilson’s disease, a condition where copper builds up in the body, can be managed with drugs which bind copper allowing it to be passed from your body in urine.

- In cholestatic liver disease, (where the flow of bile is affected due to cystic fibrosis) a medication called ursodeoxycholic acid (URSO, also referred to as UDCA) may be given.

The following therapeutic drugs were withdrawn from the market primarily because of hepatotoxicity: Troglitazone, bromfenac, trovafloxacin, ebrotidine, nimesulide, nefazodone, ximelagatran and pemoline.

Many herbal and antioxidant remedies have been advocated for chronic liver disease but the evidence is not conclusive. Some support may be found in the orthodox medical use of two of these: N-acetyl cysteine (NAC), is the treatment of choice for acetaminophen overdose; both NAC and milk-thistle (Silybum marianum) or its derivative silibinin are used in liver poisoning from certain mushrooms, notably amanita phalloides, although the use of milk-thistle is controversial. Some common herbs are known or suspected to be harmful to the liver, including black cohosh, ma huang, chaparral, comfrey, germander, greater celandine, kava, mistletoe, pennyroyal, skull cap and valerian.

The prognosis for people with ALD depends on the liver histology as well as cofactors, such as concomitant chronic viral hepatitis. Among patients with alcoholic hepatitis, progression to liver cirrhosis occurs at 10–20% per year, and 70% will eventually develop cirrhosis. Despite cessation of alcohol use, only 10% will have normalization of histology and serum liver enzyme levels. As previously noted, the MDF has been used to predict short-term mortality (i.e., MDF ≥ 32 associated with spontaneous survival of 50–65% without corticosteroid therapy, and MDF 11) and 90-day (MELD > 21) mortality. Liver cirrhosis develops in 6–14% of those who consume more than 60–80 g of alcohol daily for men and more than 20 g daily for women. Even in those who drink more than 120 g daily, only 13.5% will suffer serious alcohol-related liver injury. Nevertheless, alcohol-related mortality was the third leading cause of death in 2003 in the United States. Worldwide mortality is estimated to be 150,000 per year.

No pharmacological treatment has received approval as of 2015. Some studies suggest diet, exercise, and antiglycemic drugs may alter the course of the disease. General recommendations include improving metabolic risk factors and reducing alcohol intake. While many treatments appear to improve biochemical markers such as alanine transaminase levels, most have not been shown to reverse histological abnormalities or reduce clinical endpoints.

Bariatric surgery may also be effective.

A 2006 Cochrane review did not find evidence sufficient for the use of androgenic anabolic steroids. Corticosteroids are sometimes used; however, this is recommended only when severe liver inflammation is present.

Sylimarin has been investigated as a possible treatment, with ambiguous results. One review claimed benefit for S-adenosyl methionine in disease models.

The effects of anti–tumor necrosis factor medications such as infliximab and etanercept are unclear and possibly harmful. Evidence is unclear for pentoxifylline. Propylthiouracil may result in harm.

Evidence does not support supplemental nutrition in liver disease.

Many drug candidates are in advanced clinical studies as : elafibranor, obeticholic acid.

The treatment of chronic liver disease depends on the cause. Specific conditions may be treated with medications including corticosteroids, interferon, antivirals, bile acids or other drugs. Supportive therapy for complications of cirrhosis include diuretics, albumin, vitamin K, blood products, antibiotics and nutritional therapy. Other patients may require surgery or a transplant. Transplant is required when the liver fails and there is no other alternative.

Non-alcoholic steatohepatitis is fatty liver disease due to causes other than alcohol. No pharmacological treatment has received approval as of 2015 for NASH. Some studies suggest diet, exercise, and antiglycemic drugs may alter the course of the disease. General recommendations include improving metabolic risk factors and reducing alcohol intake. NASH was first described in 1980 in a series of patients of the Mayo Clinic. Its relevance and high prevalence were recognized mainly in the 1990s. Some think NASH is a diagnosis of exclusion, and many cases may in fact be due to other causes.

Bacterial and fungal infections are common in ALF, with one study demonstrating culture-proven infection in 80% of ALF patients. Defective cellular and humoral immunity as well as presence of indwelling catheters, coma, broad-spectrum antibiotics, and medications that suppress immunity all predispose to infection. Localizing symptoms of infection such as fever and sputum production are frequently absent and the only clues to an underlying infectious process may be worsening of encephalopathy or renal function. There must be a low threshold for obtaining frequent cultures (blood, urine, and sputum), chest radiographs, and paracentesis. Bacteria that enter through the skin, such as streptococci and staphylococci, tend to predominate. Aggressive surveillance is essential as prophylactic antibiotics have shown little benefit. Fungal infections, particularly in the setting of broad-spectrum antibiotics, are also common, and disseminated fungemia is a poor prognostic sign.

In most cases, liver function will return to normal if the offending drug is stopped early. Additionally, the patient may require supportive treatment. In acetaminophen toxicity, however, the initial insult can be fatal. Fulminant hepatic failure from drug-induced hepatotoxicity may require liver transplantation. In the past, glucocorticoids in allergic features and ursodeoxycholic acid in cholestatic cases had been used, but there is no good evidence to support their effectiveness.

An elevation in serum bilirubin level of more than 2 times ULN with associated transaminase rise is an ominous sign. This indicates severe hepatotoxicity and is likely to lead to mortality in 10% to 15% of patients, especially if the offending drug is not stopped (Hy's Law). This is because it requires significant damage to the liver to impair bilirubin excretion, hence minor impairment (in the absence of biliary obstruction or Gilbert syndrome) would not lead to jaundice. Other poor predictors of outcome are old age, female sex, high AST.

The advent of transplantation has changed survival from as low as 15% in the pretransplant era to more than 60% today. Liver transplantation is indicated for many patients with ALF, and survival rates of 56–90% can be achieved. In addition to transplantation, better critical care and the trend toward more benign causes, such as acetaminophen, all contribute to improved survival rates. Spontaneous survival is now around 40%. The application of transplantation among patients with ALF remains low, suggesting that the full potential of this modality may not be realized. Timely availability of an allograft is one of the major factors determining transplant outcomes. In the largest U.S. study, only 29% of patients received a liver graft, while 10% of the overall group (one fourth of patients listed for transplantation) died on the waiting list. Other series have reported death rates of those listed for transplant as high as 40%.

In the ALFSG, the transplantation rate was higher in the groups with lower short-term spontaneous survival, making overall survival similar in all groups: acetaminophen, 73%; drug induced, 70%; indeterminate group, 64%; and other causes,61%. Causes of death for the 101 patients who died within the 3-week period included cerebral edema, multiorgan failure, sepsis, cardiac arrhythmia or arrest and respiratory failure. The median time to death after admission was 5 days.

The treatment of fatty liver depends on its cause, and, in general, treating the underlying cause will reverse the process of steatosis if implemented at an early stage. Two known causes of fatty liver disease are an excess consumption of alcohol and a prolonged diet containing foods with a high proportion of calories coming from lipids. For the patients with non-alcoholic fatty liver disease with pure steatosis and no evidence of inflammation, a gradual weight loss is often the only recommendation. In more serious cases, medications that decrease insulin resistance, hyperlipidemia, and those that induce weight loss have been shown to improve liver function.

For advanced patients with non-alcoholic steatohepatitis (NASH), there are no currently available therapies.

Up to 10% of people with cirrhotic alcoholic FLD will develop hepatocellular carcinoma. The overall incidence of liver cancer in nonalcoholic FLD has not yet been quantified, but the association is well-established.

Bariatric surgery, while not currently recommended as a treatment for fatty liver disease (FLD) alone, has been shown to revert FLD and advanced steatohepatitis in over 90% of people who have undergone this surgery for the treatment of obesity.

"Acute on chronic liver failure" is said to exist when someone with chronic liver disease develops features of liver failure. A number of underlying causes may precipitate this, such as alcohol misuse or infection. People with ACLF can be critically ill and require intensive care treatment, and occasionally a liver transplant. Mortality with treatment is 50%.

Alcoholic hepatitis is hepatitis (inflammation of the liver) due to excessive intake of alcohol. It is usually found in association with fatty liver, an early stage of alcoholic liver disease, and may contribute to the progression of fibrosis, leading to cirrhosis. Signs and symptoms of alcoholic hepatitis include jaundice, ascites (fluid accumulation in the abdominal cavity), fatigue and hepatic encephalopathy (brain dysfunction due to liver failure). Mild cases are self-limiting, but severe cases have a high risk of death. Severe cases may be treated with glucocorticoids.

The prevalence of FLD in the general population ranges from 10% to 24% in various countries. However, the condition is observed in up to 75% of obese people, 35% of whom progress to NAFLD, despite no evidence of excessive alcohol consumption. FLD is the most common cause of abnormal liver function tests in the United States. "Fatty livers occur in 33% of European-Americans, 45% of Hispanic-Americans, and 24% of African-Americans."

Liver disease (also called hepatic disease) is a type of damage to or disease of the liver.

Severe protein deficiency can cause Laennec's cirrhosis.

Two causes have been identified. The first is malnutrition, or, more specifically, protein deprivation. This is seen in starving children who have insufficient supplies of protein and therefore manufacture insufficient amounts of lipoproteins. They develop fatty livers: it is presumed that if they survive, cirrhosis will develop.

Chronic alcoholism can cause Laennec's cirrhosis. Whether or not alcohol alone can produce fatty nutritional cirrhosis has been debated for decades. Current evidence is that it can. If so, the condition should be renamed "alcoholic cirrhosis". Those who do not subscribe to the "alcohol-as-a-poison" school state that the changes to be described are the result of malnutrition common to alcoholics. They argue that alcoholics, in a sense, are no different from those in a state of chronic protein deprivation — both have protein deprivations.

Liver failure or hepatic insufficiency is the inability of the liver to perform its normal synthetic and metabolic function as part of normal physiology. Two forms are recognised, acute and chronic. Recently a third form of liver failure known as acute-on-chronic liver failure (ACLF) is increasingly being recognized.

Many chemical agents, including medications, industrial toxins, and herbal and dietary supplements, can cause hepatitis. The spectrum of drug-induced liver injury varies from acute hepatitis to chronic hepatitis to acute liver failure. Toxins and medications can cause liver injury through a variety of mechanisms, including direct cell damage, disruption of cell metabolism, and causing structural changes. Some drugs such as paracetamol exhibit predictable dose-dependent liver damage while others such as isoniazid cause idiosyncratic and unpredictable reactions that vary among individuals. There are wide variations in the mechanisms of liver injury and latency period from exposure to development of clinical illness.

Many types of drugs can cause liver injury, including the analgesic paracetamol; antibiotics such as isoniazid, nitrofurantoin, amoxicillin-clavulanate, erythromycin, and trimethoprim-sulfamethoxazole; anticonvulsants such as valproate and phenytoin; cholesterol-lowering statins; steroids such as oral contraceptives and anabolic steroids; and highly active anti-retroviral therapy used in the treatment of HIV/AIDS. Of these, amoxicillin-clavulanate is the most common cause of drug-induced liver injury, and paracetamol toxicity the most common cause of acute liver failure in the United States and Europe.

Herbal remedies and dietary supplements are another important cause of hepatitis; these are the most common causes of drug-induced hepatitis in Korea. The United-States-based Drug Induced Liver Injury Network linked more than 16% of cases of hepatotoxicity to herbal and dietary supplements. In the United States, herbal and dietary supplements – unlike pharmaceutical drugs – are unregulated by the Food and Drug Administration. However, the National Institutes of Health maintains the LiverTox database for consumers to track all known prescription and non-prescription compounds associated with liver injury.

Exposure to other hepatotoxins can occur accidentally or intentionally through ingestion, inhalation, and skin absorption. The industrial toxin carbon tetrachloride and the wild mushroom Amanita phalloides are other known hepatotoxins.

This includes mostly drug-induced hepatotoxicity, (DILI) which may generate many different patterns over liver disease, including

- cholestasis

- necrosis

- acute hepatitis and chronic hepatitis of different forms,

- cirrhosis

- Effects of Acetaminophen (Tylenol)

- other rare disorders like focal nodular hyperplasia, Hepatic fibrosis, peliosis hepatis and veno-occlusive disease.

Liver damage is part of Reye's syndrome.

Steatosis (also called fatty change, fatty degeneration, or adipose degeneration) is the process describing the abnormal retention of lipids within a cell. It reflects an impairment of the normal processes of synthesis and elimination of triglyceride fat. Excess lipid accumulates in vesicles that displace the cytoplasm. When the vesicles are large enough to distort the nucleus, the condition is known as macrovesicular steatosis; otherwise, the condition is known as microvesicular steatosis. While not particularly detrimental to the cell in mild cases, large accumulations can disrupt cell constituents, and in severe cases the cell may even burst.

The risk factors associated with steatosis are varied, and include diabetes mellitus, protein malnutrition, hypertension cell toxins, obesity, anoxia and sleep apnea. As the liver is the primary organ of lipid metabolism it is most often associated with steatosis; however, it may occur in any organ, commonly the kidneys, heart, and muscle.