Transaminase

Transaminases are various enzymes produced by the liver. A diagnostic blood test can determine when transaminases, most commonly aspartate transaminase (AST) and alanine transaminase (ALT), are in the blood at levels above normal and healthy, i.e. are elevated.

Prognosis

The liver produces literally thousands of enzymes; it is an extremely complex and vital organ with many functions in maintaining health. Elevated transaminases are of concern because they may (although they do not always) indicate that problems exist in liver functioning or that there is damage to the liver. However, there are many causes that can result in elevated transaminases, so if this diagnostic result occurs, further investigation is needed into precisely what is causing the condition.

Definition

A transaminase, also known as an aminotransaminase, is an enzyme that acts as a catalyst for a chemical reaction between an amino acid and an alpha-keto acid. What that amounts to is that the enzyme catalyzes the conversion of one type of amino acid into another through chemical reactions. This is particularly important in all animal metabolism because of the dependence of bodies on synthesizing of amino acids to build the body’s proteins from other amino acids ingested in food.

Note that this does not apply only to meat; regardless of what an animal eats, it consists of proteins of other living organisms, and the animal’s body must convert these proteins and their component amino acids into both calories and proteins for its own use. Transaminases are important for this function of metabolism.

Liver Disease

Elevated transaminases can occur for many different reasons, some of them having little or nothing to do with liver disease. However, they are also a primary indication of possible liver disease ranging from fatty liver (relatively harmless although cause for further monitoring) to cirrhosis, hepatitis, and cancer of the liver (all quite serious and potentially life-threatening, and requiring aggressive treatment).

Because of these possibilities, when transaminases are found to be elevated, further diagnostic testing and exploration of possible causes are always indicated.

Causes

The most important causes of elevated transaminases, the ones that are cause for serious concern, are liver damage. The liver is a crucial bodily organ responsible for a wide array of metabolic, digestive, and other vital functions. A human body cannot survive without a functioning liver, at least not for long. Liver disease is one of the most serious complications of alcoholism, as well as a likely consequence of obesity and diabetes.

The most serious liver diseases are cirrhosis of the liver, hepatitis, and cancer, and all of these can produce elevated transaminases in different combinations depending on the extent of damage and the underlying causes.

Causes of elevated transaminases other than liver disease include reduced production of hormones by the adrenal glands, thyroid disorders, side effects of various medications including those used for treatment of high cholesterol levels and antibiotics as well as some seizure-disorder medicines, excessive intake of some herbal supplements, and a few other causes.

Because of the existence of causes for elevated transaminases that have nothing to do with liver disease, as well as the number of possible disorders of the liver itself and of causes for any given liver disease, further diagnostic procedures are always indicated when elevated transaminases are detected.

Pregnancy

Although elevation of some transaminases is normal during pregnancy, elevation of the two most common symptoms of liver disease, AST and ALT, is a sign that something is wrong. This occurs in roughly five percent of pregnant women. It may be a sign of liver disease, or of something specific to the pregnancy itself.Pre-eclampsia, a potentially very serious condition, characterized by high blood pressure and  urinary protein deposits, can produce elevated transaminases.

Pre-eclampsia is always a cause for concern, as it can advance to full-blown eclampsia with seizures, requiring immediate delivery of the baby or likely loss of life to both mother and child. Other acute and, thankfully, rare complications of pregnancy also may result in elevated  transaminases.