What Are the Causes of Elevated Glutamic-Pyruvic Transaminase Levels?

Update Date: 2024-06-07 Source: Network

Alanine Aminotransferase Elevation: Causes, Symptoms, and Consequences

When undergoing a physical examination, an elevated level of alanine aminotransferase (ALT) often prompts concerns about liver damage. However, there are numerous reasons for ALT elevation, beyond liver diseases. Heart and biliary diseases can also lead to increased ALT levels. Additionally, pregnant women may experience elevated ALT due to pregnancy-related factors. Therefore, it is crucial to identify the specific cause and provide targeted treatment accordingly.

I. Causes of Elevated Alanine Aminotransferase

There are various reasons for elevated ALT levels. Significant elevations are primarily observed in acute viral hepatitis. Moderate elevations can be seen in chronic hepatitis, active cirrhosis, liver cancer, liver abscess, and the use of certain medications (particularly those harmful to the liver). Mild elevations can also be attributed to myocardial infarction, myocarditis, heart failure, chronic alcohol consumption, certain biliary diseases, heart failure associated with other conditions, and fever. Additionally, normal pregnancy, pregnancy-induced hypertension, acute fatty liver of pregnancy, and other conditions can also lead to elevated ALT.

II. Symptoms of Elevated Alanine Aminotransferase

Symptoms associated with elevated ALT levels include insomnia, dreams, fatigue, poor appetite, low-grade fever, aversion to greasy food, jaundice, nausea, vomiting, abdominal pain, diarrhea, and discomfort in the liver area. Mild symptoms may manifest as excessive sweating, lethargy, thirst, and eye fatigue when reading. Given the high prevalence of hepatitis B in China, many patients with varying degrees of liver damage may experience symptoms of elevated ALT.

It's worth noting that many people mistake the symptoms of elevated ALT for hepatitis. However, various factors such as alcohol consumption, fatty liver, alcoholic liver disease, myocarditis, and influenza can also cause ALT elevations. Therefore, to determine whether the elevated ALT is due to hepatitis, additional tests, combined with a comprehensive analysis of medical history, symptoms, and physical examination findings, are necessary.

III. Consequences of Elevated Alanine Aminotransferase

Elevated alanine aminotransferase activity is a typical manifestation of various liver diseases, including acute and chronic hepatitis, cirrhosis, infectious mononucleosis, acute and chronic heart failure, various infections, metastatic cancer, granulomatous diseases, and alcoholic liver disease. An increase exceeding eightfold is nonspecific and can be observed in any of the aforementioned disease states.

The highest levels of ALT are often observed in cases of extensive hepatocyte damage, such as drug-induced or viral hepatitis and acute heart failure, where ALT levels can reach thousands or even tens of thousands of units. Levels ranging from 10,000 to 15,000 U/L may be seen in a minority of patients with unstable recovery from viral hepatitis.

ALT levels in patients with obstructive jaundice, acquired immunodeficiency syndrome (AIDS) with concomitant viral hepatitis, and cirrhosis typically reach 500 U/L, while they are usually lower than 300 U/L in alcoholic liver disease. In cases of acute bile duct obstruction caused by choledocholithiasis, ALT levels can rapidly increase to several thousand units within 24 to 48 hours of the obstruction. In most hepatobiliary diseases, ALT and aspartate aminotransferase (AST) levels tend to rise simultaneously, with ALT usually slightly higher than AST.