From the Guidelines
To diagnose the cause of elevated ALT (SGPT), I recommend ordering a comprehensive liver panel including AST, alkaline phosphatase, bilirubin (total and direct), GGT, albumin, and prothrombin time, as well as hepatitis serologies, iron studies, and autoimmune hepatitis markers, as outlined in the most recent guidelines 1. The evaluation of patients with elevated ALT requires a thorough approach to determine the underlying cause of liver damage. According to the American Gastroenterological Association medical position statement 1, the interpretation of abnormal liver chemistries must be taken in the clinical context of a given patient.
- A detailed history, inventory of medications, and physical examination should be performed to assess the patient's risk factors for liver disease, medications, alcohol consumption, comorbid conditions, and signs and symptoms of hepatic disease.
- The initial laboratory evaluation should include a comprehensive liver panel, as well as tests to rule out other causes of elevated liver enzymes, such as viral hepatitis, alcohol history, iron studies, and potential liver metastasis from primary malignancy 1.
- Additional tests, such as hepatitis serologies (hepatitis A, B, and C), iron studies (ferritin, transferrin saturation), ceruloplasmin to check for Wilson's disease, antinuclear antibody (ANA), anti-smooth muscle antibody, and anti-mitochondrial antibody to evaluate for autoimmune hepatitis, should be considered based on the patient's clinical presentation and risk factors.
- Imaging studies, such as abdominal ultrasound, may also be necessary to assess liver structure and rule out fatty liver, masses, or biliary obstruction.
- The pattern and degree of enzyme elevations, along with imaging and serologic markers, will help establish the correct diagnosis and guide treatment.
- It is essential to note that the most recent guidelines 1 prioritize a thorough workup for other causes of elevated liver enzymes, including viral hepatitis, alcohol history, iron studies, and potential liver metastasis from primary malignancy, to determine the underlying cause of liver damage and guide treatment.
From the Research
Diagnostic Approach for Elevated ALT/SGPT
To diagnose the cause of elevated Alanine Transaminase (ALT)/Serum Glutamic-Pyruvic Transaminase (SGPT), the following steps can be taken:
- Evaluate the patient's medical history, including any previous liver disease, medication use, and exposure to toxins 2, 3
- Perform liver biochemical tests, including ALT, AST, ALP, GGT, TBil, DBil, and albumin 2, 3
- Calculate the R-value to determine the clinical type and prognosis of liver injury 2
- Conduct abdominal imaging, such as ultrasonography, to evaluate liver morphology 2, 4
- Consider liver histopathological examination to aid in diagnosis and differential diagnosis 2
Potential Causes of Elevated ALT/SGPT
Elevated ALT/SGPT can be caused by various factors, including:
- Liver damage or disease, such as viral hepatitis or cirrhosis 5, 2, 3
- Muscle injury or disease, such as idiopathic inflammatory myopathies 5
- Drug-induced liver injury, such as that caused by anti-tuberculosis drugs or immune checkpoint inhibitors 2, 6
- Other medical conditions, such as myocardial infarction or obesity 3
Diagnostic Criteria and Algorithms
Diagnostic criteria and algorithms can be used to evaluate elevated ALT/SGPT, including:
- The RUCAM scale to assess causality in drug-induced liver injury 2
- The ALT:AST ratio to differentiate between hepatocellular and cholestatic liver injury 6
- An algorithmic approach to separate disease processes into hepatocellular, cholestatic, or functioning liver groupings 4
Management and Treatment
Management and treatment of elevated ALT/SGPT depend on the underlying cause, and may include: