Management of Hepatotoxicity

Introduction to Hepatotoxicity

Hepatotoxicity can be caused by various factors, including medications, viral hepatitis, and non-alcoholic fatty liver disease (NAFLD), as reported by the American Association for the Study of Liver Diseases 1 and the American Liver Foundation 2, 3
The severity classification of transaminitis is defined as:
Severity Description
Mild <3× upper limit of normal (ULN)
Moderate 3-5× ULN
Severe >5× ULN
Life-threatening >20× ULN

The following tests can provide clues to the underlying cause of transaminitis:

Test	Description
Complete blood count with platelets	Evaluate for anemia, thrombocytopenia
Comprehensive metabolic panel	Evaluate for electrolyte imbalances, kidney function
Fasting lipid profile and glucose	Evaluate for metabolic syndrome
Hepatitis B surface antigen and hepatitis C antibody	Evaluate for viral hepatitis
Serum iron, ferritin, and total iron-binding capacity	Evaluate for iron overload

Ultrasound is the first-line investigation for mild increases in liver enzymes, with 84.8% sensitivity and 93.6% specificity for detecting steatosis when hepatic fat content >33%, and the American College of Radiology recommends considering CT or MRI if ultrasound is inconclusive 8
For isolated transaminase elevation, check creatine kinase to rule out muscle origin, particularly valuable in cases of chronic hepatitis of unknown etiology 6

If no improvement after 3-5 days, consider prednisone 0.5-1 mg/kg/day, as recommended by the American Society of Clinical Oncology 9
Resume medication only when liver enzymes normalize and prednisone dose is <10 mg/day, according to the American Society of Clinical Oncology 9
For Grade 2 (AST/ALT >3.0 to ≤5.0× ULN) immune checkpoint inhibitor-related hepatitis, hold immune checkpoint inhibitor temporarily, discontinue other potentially hepatotoxic drugs, and consider steroids (0.5-1 mg/kg/d prednisone) if no improvement after 3-5 days 6
For Grade 3-4 (AST/ALT >5.0× ULN) immune checkpoint inhibitor-related hepatitis, permanently discontinue treatment, administer 1-2 mg/kg/d methylprednisolone until symptoms improve, and consider early biologics if inadequate response to steroids 6
The National Comprehensive Cancer Network recommends corticosteroids as first-line treatment for immune checkpoint inhibitor-related hepatitis, with consideration of mycophenolate for steroid-refractory cases, avoidance of infliximab due to potential liver toxicity, and potential use of tacrolimus for refractory cases 10

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of mildly elevated transaminases in developed countries, associated with obesity, type 2 diabetes, hyperlipidemia, and metabolic syndrome, according to the American Association for the Study of Liver Diseases 1
Viral hepatitis B and C are important infectious causes of transaminitis, with genotype 3 strains of hepatitis C associated with increased rates of steatosis, as reported by the American Liver Foundation 2, 3
Drug-induced liver injury (DILI) is a common cause of transaminitis, with medications such as amiodarone and tamoxifen contributing to hepatic fat accumulation, according to the European Association for the Study of the Liver 1, 11
The American Association for the Study of Liver Diseases recommends antiviral therapy with entecavir for Hepatitis B, which has the lowest rate of drug resistance in treatment-naïve patients, with monitoring for virologic breakthrough (>1 log10 increase in HBV DNA from nadir) and assessment of compliance before testing for genotypic resistance 12
Integrase inhibitors (raltegravir, dolutegravir) have fewer interactions with HCV medications and may be considered for use in patients with HCV coinfection, as recommended by the American Association for the Study of Liver Diseases 13

The American Heart Association recommends continuing statin therapy with monitoring for patients with mild-to-moderate elevations in liver enzymes (less than 3 times upper limit of normal), as statins rarely cause clinically significant liver injury, and discontinuation is only necessary when ALT/AST exceeds 5 times normal or symptoms develop 14
The American College of Cardiology and the American Heart Association support the use of statin therapy in patients with high cardiovascular risk, with appropriate monitoring for liver enzyme elevations 14, 15
Temporarily discontinue statin therapy if liver enzyme elevation is severe, and evaluate for other causes of liver enzyme elevation, then monitor liver function every 2-4 weeks until improvement, as recommended by the American Thoracic Society 16, 14
Consider non-statin lipid-lowering therapies for patients with recurrent transaminitis on statins but high cardiovascular risk, as recommended by the American College of Cardiology and the American Heart Association 14, 15

Lifestyle modifications, including weight loss (7-10% of body weight), regular exercise (150 minutes/week of moderate activity), and a Mediterranean diet, are the cornerstone of treatment for transaminitis, with monitoring for metabolic syndrome components and treatment accordingly 17
The American Association for the Study of Liver Diseases recommends monitoring every 3-6 months for mild transaminitis, every 1-3 months for moderate transaminitis, and every 2-4 weeks for severe transaminitis until improvement, with continued monitoring for at least 6 months after normalization 17
Obtain baseline liver function tests before initiating statin therapy, and regular monitoring of liver function is not required for those with no evidence of pre-existing liver disease and normal pre-treatment liver function, according to the American Thoracic Society and the American Heart Association 14, 16
Instruct patients to report symptoms such as fatigue, anorexia, right upper quadrant discomfort, dark urine, or jaundice, and liver function should be repeated if fever, malaise, vomiting, jaundice, or unexplained deterioration occurs, as recommended by the American Heart Association and the American Thoracic Society 14, 16

The CDC recommends screening all patients for pre-existing liver disease, especially hepatitis B and C, before initiating antiretroviral therapy, and considering hepatitis A and B vaccination for susceptible patients with chronic HCV 18
The American College of Physicians recommends obtaining baseline liver enzymes (ALT, AST) before initiating antiretroviral therapy and monitoring every 2 weeks when initiating therapy in patients with pre-existing liver disease, and monthly once stable 19
Monitor for drug interactions that may increase the risk of hepatotoxicity, as interactions such as those involving cytochrome P450 inhibitors can significantly affect medication levels and increase liver injury risk, according to the European Association for the Study of the Liver (EASL) and the American College of Clinical Pharmacology 20, 6, 7