L'alanine aminotransferase (ALT or GPT) is an enzyme protein found mainly in the liver and kidneys. The feedback from High ALT and then of high transaminases it is often suggestive of a liver problem.
The finding of high values ALT, and transaminases in general, in blood tests, is an indication of the presence of an insult that is causing damage to the liver.
L'ALT, together with the other liver enzyme, AST, is also used to diagnose and monitor the course of acute or chronic liver disease over time. L'alanine aminotransferase it is abbreviated with the abbreviation ALT, or with GPT, and is usually dosed in blood tests together with another transaminase, theaspartate aminotransferase, (also called AST or GOT) as part of a set of tests that help evaluate liver function, to determine the presence and possible severity of a liver organ.
What is ALT
What are the transaminases? what is that the ALT? ALT is one of the transaminases, it is an enzyme found mainly in the liver and kidneys.
L'ALT it is more specific for detecting liver damage, as it is concentrated mainly in the liver and has a longer half-life, ie it remains in the blood for longer. Conversely, AST is found in many other organs besides the liver, and its elevation is not necessarily a sign of liver damage. Both are often referred to as hepatic cytolysis enzymes or simply liver enzymes.
In some liver diseases, theAST is higher than ALT, for example in liver damage from alcohol abuse, in cirrhosis and hepatocellular carcinoma. In particular, a AST to ALT ratio greater than 2 suggests the possibility that there has been a significant alcohol damage, and an AST / ALT ratio greater than 3 is strongly indicative of acute alcohol damage.
How does ALT? ALT is an enzyme, which catalyzes (ie promotes) the transfer of an amino group from the amino acid alanine to the alpha-ketoglutarate. The products of this reversible transamination reaction are pyruvate and glutamate, as seen in the following formula:
glutamate + pyruvate ⇌ α-ketoglutarate + alanine
The synthesis of ALT depends on the vitamin B6 (pyridoxal or pyridoxine) and is therefore decreased in all those situations in which low levels of vitamin B6 coexist, as happens in people malnourished, in patients with chronic significant reduction in renal function (chronic renal failure) and liver function (cirrhosis of the liver).
Normal values of ALT
THE normal reference levels for ALT are included between 20 and 60 IU / L (International Units on Liter).
Causes of high ALT OR GPT - high alanine aminotransferase
There are a number of conditions associated with the finding of transaminases ALT-GPT high. Here are the most common causes of high alanine aminotransferase.
Very high ALT-GPT
Below are the most frequent causes of a massive alteration of alanine aminostransferase:
- Acute liver damage: acute hepatitis is an acute inflammation of the liver, which can lead to a simple increase in tranasminase and cholestasis indices, but also to an impairment of the liver protein synthesis function, up to fatal hepatic insufficiency. Transaminase levels are not necessarily correlated with prognosis, i.e., paradoxically, patients with a significant increase in AST and ALT may have complete resolution of the problem without sequelae, while people with minimal transaminase alterations may already be hiding advanced liver disease. forms of acute hepatitis are:
- Acute hepatitis B: acute viral hepatitis linked to HBV infection
- Acute hepatitis A: acute viral hepatitis linked to HAV infection
- Acute hepatitis E: acute viral hepatitis linked to HEV infection,
- Acute alcoholic hepatitis: occurs after an excessive intake of alcohol, usually spirits
- Acute autoimmune hepatitis: more frequent in women than in men, it is secondary to an attack of our own organism against the liver tissue.
- Acute drug-induced hepatitis: classic example is acute paracetamol hepatitis, it can occur when you take more than 4 g per day of tachipirina
- Acute fungal hepatitis: for example acute hepatitis due to amanita phalloides
- Tumor necrosis: for example in the presence of primary liver cancer (hepatocellular carcinoma or HCC) or in the presence of secondary metastases of other neoplasms (especially prostate or colon cancers).
ALT-GPT quite high
The conditions associated with the levels moderately elevated ALT They are the following:
- Chronic liver disease
- Chronic hepatitis / cirrhosis B: chronicization of HBV hepatitis
- Chronic hepatitis / cirrhosis C: chronicity of an HCV infection
- Chronic hepatitis / cirrhosis from iron overload in the liver, as in hemochromatosis
- Chronic hepatitis / cirrhosis of autoimmune etiology: Sometimes our immune system goes crazy and attacks the cells of the liver tissue (hepatocytes) or the biliary channels (biliocytes). Autoimmune liver diseases are mainly:
- autoimune hepatitis / cirrhosis,
- primary sclerosing cholangitis,
- primary biliary cirrhosis.
- Alcohol abuse with an intake of more than 3 alcoholic units per day (one alcoholic unit corresponds more or less to a glass of wine, a small beer or a glass of spirits)
- Cholestasis (for example when a stone occludes the biliary tract, causing a major increase in GGT, ALP and bilirubinemia, but often only a modest increase in GOT and GPT).
- Heart damage: ALT also increases in the case of an insult to the heart tissue (myocardium), such as in the case of a heart attack or heart failure (heart failure). In fact, during myocardial infarction transaminases are released due to damage to the heart muscle, but also due to the possible ischemic damage secondary to the reduced blood flow to the liver. In heart failure, on the other hand, the major cause of ALT and AST elevation is hepatic suffering linked to congestion ("stagnation") of venous blood which is not pumped sufficiently and stagnates upstream of the right ventricle, giving rise to the so-called stasis liver.
- Kidney damage acute: in the case of acute renal insufficiency, especially of the ischemic type, ALT may be released into the circulation.
- Muscle damage or injuries: in the event of intense physical exertion or a trauma to our muscles, blood tests carried out in the following days could show an increase in GPT and GOT.
- Hemolysis: when it happens that a large number of erythrocytes (red blood cells circulating) are destroyed in a short period of time, there may be an increase in bilirubin and transaminases and in cholestasis indices.
- Heat stroke: in the case of intense heat stroke, damage to body tissues can occur with the release of alanine aminotransferase and aspartate transaminase (ALT and AST).
- High consumption of vitamin A.
- Mononucleosis: secondary infection to the Epstein Barr virus (EBV), can also temporarily affect the liver and spleen, enlarging their volume and causing an increase in transaminases.
- Cytomegalovirus infection: As in the case of Epstein Barr Virus (EBV) mononucleosis, CMV infection can settle in the liver and cause an elevation in ALT and AST.
Mildly elevated ALT-GPT
Conditions associated with just high levels of ALT They are the following:
- Fatty liver: hepatic steatosis is a condition in which the liver contains an increased concentration of lipids, and is therefore frequently called by the term fat liver. It is not serious but can become serious if the necessary remedies are not implemented (diet, physical activity, abstention from alcohol)
- Use of alcohol, even without exceeding 3 alcoholic units per day. Even a modest use of wine or beer with meals can, in predisposed people, slightly alter ALT and AST levels.
- Cirrhosis of the liver low degree of activity. Cirrhosis of the liver with a reduced degree of inflammation, such as exotoxic cirrhosis in a person who has stopped drinking, or HBV cirrhosis in a person on antiviral therapy, or HCV cirrhosis with reduced viral activity, may exhibit a mild elevation of GPT and GOT.
- Elevated ALT in pregnancy: the finding of high transaminases in pregnancy it is frequent, and often benign, linked to weight gain with consequent fatty liver disease during gestation. In any case, in the event of a high transaminase finding during pregnancy, the treating doctor or gynecologist must always be notified and promptly investigated to identify the cause.
Medication and high ALT or GPT - high alanine aminotransferase
THE medications how can they cause a increase in ALT and AST?
Hepatocellular damage caused by drugs can be transient and / or minor, but also very serious, and of a definitive nature.
Here is a list of very common medications that can cause ALT and AST to rise:
- Valproic acid and sodium valproate
High ALT - High GPT Symptoms - High Transaminase Symptoms
What are the symptoms of a high alanine aminotransferase? THE high ALT symptoms they are the ones that suggest a liver disease, or another organ that can release transaminases. Here are the main symptoms of High GPT:
- Weakness and fatigue, takes the medical name of asthenia and typically characterizes liver disease
- Nausea with or without He retched: characterizes acute pathologies of the liver
- Feeling of bloating and abdominal tension, it could be simple meteorism or the initial accumulation of fluid in the peritoneal cavity (ascites)
- Abdominal pain, is not uncommon in patients with cirrhosis and ascites due to the high incidence of urinary and peritoneal infections
- Skin and scleral jaundice: yellowing of the eyes and skin.
- Dark urine: it is often a sign related to bilirubinuria, ie the presence of urinary bilirubin
- Made clear: the presence of grayish stools, such as clay, may be a sign of obstructed biliary outflow, a frequent sign in liver disease.
- Very dark stools: also the presence of blackish stools, like coffee grounds, can signal the presence of blood now digested in the excrement: that is, it is caused by acute or chronic grastrointestinal bleeding, which is frequent in diseases characterized by increased portal pressure such as pathologies liver diseases.
- itch: it is frequent in liver diseases, it is due to the increase in circulating bile salts
- Alteration of behavior, confusion, daytime sleepiness and nighttime sleeplessness
- Chest pain, shortness of breath, need to sleep with two or three pillows, swelling in the legs and jugular veins if you have heart problems
- Reduction of diuresis: Doing little pee during the day is a warning sign, it can frequently occur in advanced cirrhosis, but also during heart failure.
- Skin hematomas in case of a recent muscle trauma. It should be noted that even in the course of cirrhosis, the reduction of platelets and the alteration of the coagulation system favor the appearance of hematomas.
When to take the exam
When is ALT measured? When are transaminases measured? The transaminases GPT and GOT (ALT and AST) should be measured:
When liver disease is suspected: liver disease might be suspected if there are signs and symptoms of liver distress, i.e .:
- Easy weakness and fatigue (asthenia)
- Loss of appetite (hyporexia)
- Nausea and / or vomiting
- Swelling and / or abdominal pain, which could be bloating or the initial buildup of fluid in the abdomen (ascites)
- Yellow discoloration of the eyes and skin (jaundice)
- Dark (brown or greenish) urine
- Clear stools (clay-like)
- Very dark stools (such as coffee grounds)
- behavior changes
- sleepiness during the day and sleeplessness at night
ALT analysis could also be useful in particular categories of people, at risk for liver disease:
- People who have may have been exposed to one or more hepatitis viruses
- People who have a history of previous acute hepatitis
- People who abuse alcohol, even if they only do it with meals
- People who have or have had other relatives with liver disease in the family
- People who use chronic drugs that can damage the liver.
- People who have occasionally abused drugs such as paracetamol or other hepatotoxic substances
- People with diabetes or overweight
Furthermore, ALT and transaminases in general are useful for monitoring liver function in people who do not have liver problems:
- Chronic hepatitis or cirrhosis B (HBV)
- Chronic hepatitis or cirrhosis C (HCV)
- Chronic hepatitis or alcoholic cirrhosis
- Hepatitis or autoimmune cirrhosis
- Genetic hemochromatosis or secondary to iron overload
- Wilson's disease
- Primary biliary cholangitis (until recently called primary biliary cirrhosis)
- Primary sclerosing cholangitis
- People undergoing liver transplantation
What do you need and how do you make the withdrawal?
ALT will be measured using a small amount of blood usually drawn from the crook of the arm. You don't need to be fasting to take the exam.Tags: Laboratory medicine Blood