From the Guidelines
Elevated liver enzymes are a significant indicator of potential liver damage or inflammation, and prompt consultation with a healthcare provider is essential for proper evaluation and management. The most common causes of elevated liver enzymes include nonalcoholic fatty liver disease (NAFLD), alcohol-induced liver disease, viral hepatitis, and medication-induced liver injury 1. According to the American College of Radiology, hepatocellular injury causes the release of ALT and AST in serum, and an increase in ALT is directly linked to hepatocyte injury 1.
Key Considerations
- The AST:ALT ratio is generally >2 in alcohol-induced fatty liver disease and <1 in metabolic disease-related fatty liver 1.
- NAFLD is the most common liver disease in first-world countries, with a prevalence of 20% to 30% in the general population, increasing to 70% with obesity and 90% with diabetes mellitus 1.
- The European Association for the Study of the Liver (EASL) recommends screening for NAFLD in individuals with persistently abnormal liver enzymes, as NAFLD is the main reason for unexpectedly elevated liver enzymes 1.
Management and Treatment
- Stopping alcohol consumption and reviewing medications are crucial steps in managing elevated liver enzymes.
- For fatty liver disease, lifestyle changes including weight loss, regular exercise, and a balanced diet low in processed foods and sugar are recommended 1.
- For viral hepatitis, antiviral medications may be prescribed.
- Monitoring is essential, with follow-up blood tests typically scheduled within 2-4 weeks to track enzyme levels 1.
Diagnosis and Evaluation
- A complete liver panel, hepatitis screening, or imaging studies like ultrasound or CT scan may be ordered to evaluate the underlying cause of elevated liver enzymes 1.
- The diagnosis of alcoholic liver disease (ALD) is made by documentation of alcohol excess and evidence of liver disease, and no single laboratory marker definitively establishes alcohol to be the etiology of liver disease 1.
From the Research
Causes of Elevated Liver Enzymes
- Elevated liver enzymes can be caused by various factors, including infectious, autoimmune, genetic, metabolic, drug, and vascular causes 2, 3
- The pattern of aminotransferase and alkaline phosphatase elevations can help narrow down the differential diagnosis 2, 4
Evaluation and Diagnosis
- A thorough history and physical examination, appropriate blood testing, and imaging are typically key to evaluating the patient with abnormal liver enzymes 2
- The clinical presentation and pattern of injury should guide the evaluation 3
- Liver biopsy may be reserved for patients for whom less invasive investigations are unfruitful 4
Specific Causes and Management
- Autoimmune hepatitis is an inflammatory disease of the liver that may progress to liver cirrhosis and end-stage liver failure if diagnosis is overlooked and treatment delayed 5
- The diagnosis of autoimmune hepatitis is based on a specific set of autoantibodies, increased IgG concentrations, and histological demonstration of interface hepatitis and periportal necrosis 5
- Imaging exams have a limited role in the clinical management of autoimmune hepatitis, but can help exclude overlapping syndromes and assess complications related to cirrhosis 6
Treatment and Prognosis
- Treatment of autoimmune hepatitis aims to induce and maintain long-term remission of liver inflammation, and can often reverse liver fibrosis 5
- Most patients with autoimmune hepatitis need lifelong maintenance therapy, and repeated follow-up in experienced hands improves the quality of care and quality of life for affected patients 5