From the Guidelines
For a workup of elevated Liver Function Tests (LFTs), a detailed history, inventory of medications, and physical examination should be performed, followed by targeted laboratory tests and imaging studies as indicated by the clinical scenario, as recommended by the American Gastroenterological Association 1. The initial evaluation of abnormal liver tests should include an assessment of the patient’s risk factors for liver disease, medications, alcohol consumption, comorbid conditions, and signs and symptoms of hepatic disease.
- Key components of the workup include:
- Repeating LFTs to confirm elevation
- Obtaining a detailed history, focusing on alcohol use, medications, supplements, and risk factors for viral hepatitis
- Performing a physical examination, looking for signs of chronic liver disease
- Ordering targeted laboratory tests, such as hepatitis B and C antibodies, iron studies, and autoimmune markers, based on the clinical scenario
- Considering imaging studies, such as abdominal ultrasound, to evaluate liver morphology and detect potential liver lesions
- The evaluation of patients with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) elevations should be guided by the clinical context, with common hepatic diseases excluded with noninvasive serologic tests, and additional testing or observation determined by the clinical scenario 1.
- A stepwise approach to the workup of elevated LFTs, taking into account the patient's clinical presentation, medical history, and laboratory results, is essential for efficient diagnosis and management of liver disease, and for preventing progression of liver disease and initiating timely treatment 1.
From the Research
Workup for Elevated Liver Function Tests (LFTs)
The workup for elevated LFTs involves a series of steps to determine the underlying cause and severity of liver disease.
- The first step is to determine whether the abnormal LFTs are associated with the current illness or preceded it 2.
- The second step is to determine the etiology of the underlying liver disease, which can be done by evaluating the pattern of LFT abnormalities 3, 4.
- The third step is to evaluate the severity of liver dysfunction and determine if acute liver failure or acute decompensation of chronic liver failure is present 2.
- The final step is to look for the presence of associated complications, such as those of acute liver failure or chronic liver failure 2.
Laboratory Evaluation
Laboratory evaluation of patients with elevated LFTs typically involves a broad array of biochemical tests, including:
- Aspartate aminotransferase (AST)
- Alanine aminotransferase (ALT)
- Alkaline phosphatase
- Bilirubin
- Albumin These tests can help to screen for liver disease, suggest the underlying cause, estimate the severity, assess prognosis, and monitor the efficacy of therapy 4.
Diagnostic Tools
Diagnostic tools that may be used in the workup for elevated LFTs include:
- Abdominal sonography 5
- Hepatotropic virus workup 5
- Other imaging studies, such as CT or MRI scans, may also be used to evaluate the liver and bile ducts.
Special Considerations
Special considerations in the workup for elevated LFTs include:
- The patient's age, with older patients being more likely to have advanced fibrosis 3
- The patient's medical history, including any history of liver disease or other medical conditions that may affect the liver
- The presence of any symptoms, such as jaundice, fatigue, or abdominal pain, that may indicate liver disease.