Fatty liver is an accumulation of fat in liver tissue. Ordinarily, the liver’s triglycerides are packaged into very-low- density lipoproteins (VLDL) and exported to the blood stream. Although the exact reason why fat accumulates is unknown, fatty liver represents an imbalance between the amount of fat synthesized or picked up from the blood and the amount exported to the blood via VLDL.
Fatty liver is clinical finding that is common to many conditions. It is present in the majority of patients who have alcoholic liver disease and can also result from exposure to drugs and toxic metals. It is associated with obesity, diabetes mellitus, and disease of malnutrition, including kwashiorkor and marasmus.
Fatty liver may follow gastrointestinal bypass surgery or long-term total parenteral nutrition. The causes of fatty liver are not always clear, however and it occurs in as many as 14% of adults in the United States.
Causes of Fatty liver
The two basic conditions under which fatty change, also known as steatosis, occurs in the liver are:
- A. Excess of fat is brought to the liver beyond its capacity to metabolize. This is sometimes called fatty infiltration.
- B. The liver cell is damaged so that it cannot metabolize the normal or increased quantities of fat brought to it. This is at times called by the fatty degeneration.
- A. Conditions of Excess Fat: Hyperlipidemia
i. Diabetes mellitus
iii. Congenital Hyperlipidemia
- B. Conditions of diseased Liver Cells
i. Metabolic disorders
- Alcoholic liver disease
- Protein calorie malnutrition
- Cushing’s syndrome
- Drug induced liver disease: e.g. paracetamol methotraxate, tetracycline, steroids, carbon tetrachloride, halothane anesthesia and phosphorus poisoning.
ii. Infections, toxic and miscellaneous conditions
- Viral hepatitis
- Reye’s syndrome (fatty liver with encephalitis)
- Acute fatty liver of pregnancy
- Anoxic conditions- congestive cardiac failure, severe anemia’s
- Chronic debilitating conditions
Of these the common conditions in which fatty liver is met with are:
Alcohol is among the most common cause. The mechanisms are multiple, namely (i) direct toxicity to the cell from the acetaldehyde and acetates liberated from the alcohol (ii) nutritional imbalance in the intake of proteins and fat by the alcoholic and (iii) associated obesity/ diabetes mellitus which is more common in the alcoholics.
Alcoholics, diabetics and steroid treated subject also cause greater release of FFA from the depot fats.
Protein-calorie malnutrition also known as Kwashiorkor implies lack of proteins in the diet or intake of proteins of poor quality or protein quantity intake disproportionately less than the quantity of carbohydrates.
The lack of protein leads to the deficiency of amino acids that are needed by the liver for the conversion of fat to phospholipids, lipoproteins and to transport fat/ cholesterol from the cells by apoproteins. Similar fatty change appears in the liver cells in the presence of toxins/ poisons that prevent protein synthesis, such agents are CCI, tetracycline, phosphorus. .
Drug and chemicals lead to fatty change by interfering with enzyme activity in the liver cell. Reye’s syndrome is a condition of high fever, convulsions due to a viral encephalitis and massive fatty change in the liver in small children. Aspirin that is given to these children for the fever has been blamed for the fatty change.
Anoxic/ hypoxic conditions like severe anaemia and congestive cardiac failure are usually accompanied by fatty change. Lack of oxygen prevents the oxidation of the FFA. Since the hypoxia is felt most in the central zones of the lobules the fatty change is also maximum in the central zones.
In diabetes mellitus and obesity there is gross excess of fat coming to the liver and some of it accumulates in the cell.
Sign and symptoms of fatty liver
Clinical features of fatty liver vary with the degree of lipid infiltration, and many patients are asymptomatic. The most typical sign is a large, tender liver (hep-atomegaly). Common signs and symptoms include right upper quadrant pain (with massive or rapid infiltration), ascites, edema, jaundice, and fever (all with hepatic necrosis or biliary stasis). Nausea, vomiting, and anorexia are less common. Splenomegaly usually accompanies cirrhosis. Rarer changes are spider angiomas, varices, transient gynecomastia, and menstrual disorders.
Diagnosis of fatty liver
Typical clinical features — especially in patients with chronic alcoholism, malnutrition, poorly controlled diabetes mellitus, or obesity—-suggest fatty liver.
CONFIRMING DIAGNOSIS: – A liver biopsy confirms excessive fat in the liver these liver function tests support this diagnosis.
- Albumin–somewhat low
- Globulinâ€”usually elevated
- Cholesterolâ€”usually elevated
- Total bilirubinâ€”elevated
- Alkaline phasphataseâ€”elevated
- Prothrombin timeâ€”possibly prolonged
Other findings may include anemia, leucocytosis, elevated white blood cells count, albuminuria, hyperglycemia or hypoglycemia, and iron, folic acid, and vitamin B12 deficiencies.
Treatment of fatty liver
Treatment of fatty liver is essentially supportive and consists of correcting the underlying condition or eliminating its cause. For instance, when fatty liver results from parenteral nutrition, decreasing the rate of carbohydrate infusion may correct the disease.
In alcoholic fatty liver, abstinence from alcohol and proper diet can begin to correct liver changes within 4 to 8 weeks. Such correction requires comprehensive patient teaching.
Providing support to the patient and his family is an important element in the care of the patients.
- Suggest counseling for the alcoholic patient and provide emotional support for his family.
- Teach the patient with diabetes — and his family about proper care, such as the purpose of insulin injections, diet, and exercise. Refer him to home health nurse or to group classes, as necessary, to promote compliance with treatment. Emphasize the need for long-term medical supervision and urge him to report any changes in his health immediately.
- Instruct an obese patient and his family about proper diet. Warn against fad diets, which are usually nutritionally inadequate. Recommend medical supervision for a patient who’s more than 20% overweight. Encourage attendance at group diet and exercise programs and, if necessary, suggest behavior medication programs to correct eating habits. Be sure to follow up on his progress and provide positive reinforcement for any weight loss.
- Assess for malnutrition, especially protein deficiency, in the patient with chronic illness. Suggest dietary changes and refer the patient to a dietitian.
- Advise patients receiving hepatotoxins and those who risk occupational exposure to DDT to watch for and immediately report signs of toxicity.
- Inform the patient that fatty liver is reversible only if he strictly follows the therapeutic program; otherwise, he risks permanent liver damage.
Fate of Fatty Liver