Transaminitis is the medical term for having elevated levels of specific liver enzymes in the bloodstream, a finding typically made during routine blood work. This elevation is not a disease in itself but rather a biochemical signal that liver cells, or hepatocytes, have been injured or inflamed. These enzymes, primarily alanine aminotransferase (ALT) and aspartate aminotransferase (AST), leak out of the damaged liver cells and into the circulation, raising their measurable concentrations. The presence of transaminitis prompts a deeper investigation to determine the underlying issue affecting the liver or other tissues.
The Function of ALT and AST Enzymes
The two enzymes central to transaminitis, Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST), play important roles in metabolism, specifically in processing amino acids. Both enzymes facilitate the transfer of an amino group from an amino acid to an alpha-keto acid, a process known as transamination. This action allows the body to generate energy and synthesize new proteins.
ALT is highly concentrated within the liver, making it the more specific indicator of liver cell damage. AST is found in various tissues outside the liver, including the heart, skeletal muscles, kidneys, and red blood cells. Therefore, elevated AST without a corresponding rise in ALT may suggest a problem originating from a non-liver source, such as a muscle injury or a heart condition.
Primary Factors Leading to Elevated Levels
The most common reason for elevated liver enzymes is metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as NAFLD. This condition is strongly associated with obesity, type 2 diabetes, and high cholesterol, involving the accumulation of excess fat within liver cells. When this accumulation progresses to Non-Alcoholic Steatohepatitis (NASH), the injury is more severe, increasing the risk of scarring and advanced liver disease.
Frequent causes include substances toxic to the liver, such as alcohol and certain medications. Alcohol-related liver disease often causes significant enzyme elevation with a distinct pattern. Numerous prescription drugs (like statins) and over-the-counter pain relievers (like acetaminophen) can cause liver stress and enzyme leakage. Many herbal supplements can also induce liver injury and should be reviewed with a healthcare provider.
Non-hepatic causes also contribute to elevated transaminases. These include strenuous exercise, which causes temporary muscle breakdown, or underlying issues such as celiac disease and thyroid disorders.
Viral infections, such as chronic hepatitis B and C, cause ongoing inflammation and injury to the liver cells. Less common, serious genetic conditions, including hereditary hemochromatosis (excess iron storage) or Wilson disease (copper accumulation), may also present with transaminitis.
Understanding the Severity of Transaminitis
Clinicians interpret transaminitis by its magnitude relative to the upper limit of normal (ULN). Mild transaminitis (one to two times the ULN) is often associated with chronic, low-grade conditions like MASLD. Moderate elevations (three to five times the ULN) may point toward more active inflammation or a recent injury.
A severe elevation (greater than ten times the ULN) usually indicates an acute and significant liver injury. Causes include acute viral hepatitis, sudden bile duct obstruction, or severe drug-induced toxicity, such as an acetaminophen overdose. The ratio between AST and ALT levels, known as the De Ritis ratio, provides a diagnostic hint: in most liver diseases, ALT is higher than AST, meaning the ratio is less than one.
A ratio greater than two (AST more than double the ALT) is highly suggestive of alcohol-related liver disease, especially when accompanied by elevated gamma-glutamyl transferase (GGT). An AST greater than ALT can also occur in advanced liver scarring (cirrhosis) or from significant muscle trauma. Differentiating between acute (sudden) and chronic (long-term) elevation is important, as massive spikes imply a rapid, severe event, while persistent, low-level elevations suggest an ongoing process.
Diagnostic Follow-up and Management
Once elevated transaminases are detected, a comprehensive evaluation pinpoints the source of the injury. Initial follow-up includes laboratory tests to assess overall liver function, such as checking levels of bilirubin, alkaline phosphatase, and GGT. Specific blood tests are also conducted to rule out common infectious causes, including panels for hepatitis A, B, and C viruses.
Further testing checks for metabolic issues, such as a fasting lipid profile and glucose level, or genetic conditions like hemochromatosis using iron and ferritin studies. Imaging, typically an abdominal ultrasound, is used to visualize the liver, check for fat accumulation, and assess the bile ducts for obstruction.
Management is directed at the underlying cause once identified. For the most common cause, MASLD, treatment centers on lifestyle modifications, including weight loss, dietary changes, and regular physical activity. If a medication or supplement is suspected, the provider reviews all current prescriptions, often stopping or substituting the potential culprit.
Patients are advised to limit or completely avoid alcohol, as it can worsen any form of liver injury. While many cases of transaminitis are mild and resolve with conservative management, immediate medical attention is necessary if the patient experiences symptoms such as jaundice (yellowing of the skin or eyes), severe abdominal pain, or confusion.