Liver and Kidney Function Tests: A Comprehensive Guide
The liver and kidneys are two of the most vital organs in the human body, playing crucial roles in metabolism, detoxification, and waste elimination. Proper functioning of these organs is essential for maintaining overall health. Liver function tests (LFTs) and kidney function tests (KFTs) are performed to evaluate the efficiency and health of these organs. Among the many biomarkers used to assess liver and kidney function, four key indicators include Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Blood Urea Nitrogen (BUN), and Creatinine. These tests are commonly ordered as part of routine health check-ups or when there is a suspected dysfunction in the liver or kidneys. Understanding the significance of these tests and their implications can help in the early detection and management of various diseases.
Liver Function Tests (LFTs)
Liver function tests measure various enzymes and proteins in the blood to assess liver health. The liver performs numerous essential functions, such as filtering toxins from the blood, producing bile for digestion, and metabolizing nutrients. Any damage or disease affecting the liver may lead to abnormal levels of certain enzymes and proteins.
Alanine Aminotransferase (ALT)
What is ALT?
Alanine Aminotransferase (ALT) is an enzyme found primarily in the liver. It plays a crucial role in amino acid metabolism by facilitating the conversion of alanine into pyruvate. ALT is released into the bloodstream when liver cells are damaged or destroyed, making it a valuable marker for liver health.
Normal ALT Levels
In healthy individuals, ALT levels typically range between 7 to 56 units per liter (U/L).
However, reference ranges may vary depending on the laboratory and testing methods used.
Causes of Elevated ALT Levels
Elevated ALT levels may indicate liver damage or disease. Some common causes include:
Hepatitis (viral, alcoholic, or autoimmune): Liver inflammation due to infections or excessive alcohol consumption.