From the Guidelines
Based on the blood results, I would recommend further investigations to evaluate the elevated liver enzymes, including a hepatitis panel, an ultrasound of the liver and biliary system, and additional liver function tests such as prothrombin time and INR, as suggested by the guidelines on the management of abnormal liver blood tests 1. The patient's ALT (92 U/L), AST (78 U/L), and GGT (40 U/L) are all elevated above their reference ranges, suggesting hepatocellular injury. The normal alkaline phosphatase (ALP) with elevated transaminases points toward a hepatocellular rather than cholestatic pattern of liver injury. I would also recommend a complete blood count to assess for any hematological abnormalities and a lipid profile to evaluate for non-alcoholic fatty liver disease. Additionally, the estimated GFR of 57 mL/min indicates mild renal impairment, so a urinalysis and urine protein-to-creatinine ratio would be appropriate to further evaluate kidney function. A detailed medication history and alcohol consumption assessment are essential as these could be contributing to the liver enzyme elevations, as highlighted in the guidelines for the management of alcohol-related liver disease 1. If the patient has risk factors, testing for autoimmune hepatitis (ANA, ASMA, immunoglobulins) and metabolic liver diseases (iron studies, ceruloplasmin) might also be warranted. The recent guidelines on the role of noninvasive biomarkers in the evaluation and management of nonalcoholic fatty liver disease suggest that a Fibrosis 4 Index (FIB-4) can be used as a first-line point-of-care test to exclude advanced hepatic fibrosis 1. However, given the patient's elevated liver enzymes, a more comprehensive evaluation, including noninvasive tests such as enhanced liver fibrosis (ELF), vibration-controlled elastography (VCTE), or magnetic resonance elastography (MRE), may be necessary to assess the degree of liver fibrosis. Ultimately, the choice of investigations will depend on the patient's individual risk factors, clinical presentation, and the results of initial tests. Key considerations in the evaluation of abnormal liver blood tests include:
- A thorough clinical history, including age, ethnicity, symptoms, comorbidity, drug history, and travel history
- A targeted clinical examination to look for signs of chronic liver disease
- A standard liver aetiology screen or core panel to identify the cause of damage and exclude additional pathologies
- Referral to a specialist clinic if necessary, based on locally agreed guidance.
From the Research
Additional Investigations
Based on the patient's blood test results, the following additional investigations are recommended:
- Liver ultrasound to assess for fatty liver disease or other liver abnormalities, as elevated ALT and AST levels suggest hepatocellular injury 2, 3
- Viral hepatitis screening (e.g., hepatitis A, B, and C) to rule out infectious causes of liver enzyme elevation 2, 3
- Assessment for nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) given the patient's elevated liver enzymes 2, 3
- Screening for hereditary hemochromatosis, autoimmune hepatitis, Wilson's disease, and alpha-1 antitrypsin deficiency to rule out genetic or autoimmune causes of liver disease 2, 3
- Review of the patient's medication history to identify potential causes of liver enzyme elevation 3
- Consideration of a liver biopsy if serologic testing and imaging fail to elucidate a diagnosis, or to stage a condition 3
Rationale
The patient's elevated ALT and AST levels suggest hepatocellular injury, which can be caused by a variety of factors, including viral hepatitis, NAFLD, and genetic or autoimmune disorders 2, 3. A liver ultrasound can help assess for fatty liver disease or other liver abnormalities, but its accuracy may be limited in patients with chronic liver disease 4. A high-frequency ultrasound may be more useful in diagnosing cirrhosis, with a sensitivity of 87.5% and specificity of 81.5% 5.
Next Steps
The results of these additional investigations will help guide further management and treatment of the patient's liver disease. It is essential to interpret the patient's liver biochemical tests accurately and consider the pattern and magnitude of aminotransferase elevation to determine the underlying cause of the abnormal results 2, 3.