Liver Enzyme Monitoring in HIV Patients on Antiretroviral Therapy

Initial Monitoring Strategy

For clinically stable HIV patients on antiretroviral therapy with viral suppression, liver enzyme monitoring should be performed every 6 months during the first year, then can be reduced to annually after 5 years of stable suppression, with more frequent monitoring (every 2 weeks to monthly) only during the first 12 weeks if using nevirapine or in patients with hepatitis coinfection, as recommended by the American Medical Association 1, 2
Baseline liver function tests, including AST, ALT, and bilirubin, should be obtained to characterize general health before initiating therapy, according to the American College of Physicians 3
Screen for viral hepatitis A, B, and C coinfection, as these significantly increase hepatotoxicity risk, as stated by the Centers for Disease Control and Prevention 1, 2, 3

After achieving viral suppression, monitor safety laboratories, including liver enzymes, every 6 months for the first year, then every 6 months for 1-5 years, and annually after 5 years if the patient remains clinically stable, virologically suppressed, and adherent, as recommended by the American Medical Association 1, 2
For patients with hepatitis C coinfection, closer monitoring is warranted due to the increased risk of severe hepatotoxicity, as stated by the American Association for the Study of Liver Diseases 4, 5, 6

Protease inhibitor (PI) regimens can cause hepatotoxicity at any time during treatment, and ritonavir-containing regimens have higher rates of severe hepatotoxicity, according to the National Institutes of Health 4, 5, 6
Integrase inhibitor regimens have superior hepatic safety profiles compared to NNRTIs and PIs, as stated by the World Health Organization 7
Injectable cabotegravir PrEP requires liver enzyme testing every 6 months, as recommended by the Centers for Disease Control and Prevention 8

Asymptomatic mild elevations (3-5x ULN) in liver enzymes may resolve spontaneously without therapy modification, but symptomatic or severe elevations require assessment for clinical hepatitis symptoms and consideration of ART modification or interruption, as stated by the American College of Gastroenterology 4, 5, 6

Do not delay ART initiation while waiting for baseline liver function results unless severe preexisting liver disease is evident, as recommended by the American Medical Association 3
Do not routinely withhold HAART from hepatitis-coinfected patients, but monitor closely for immune reconstitution hepatitis, as stated by the Centers for Disease Control and Prevention 9

The American College of Physicians recommends monitoring for hepatotoxicity, defined as 3-5 times elevation in serum transaminases, which has been reported with all antiretroviral classes, including integrase inhibitors like bictegravir, with a strength of evidence based on clinical trials 10
The majority of patients with mild transaminase elevations remain asymptomatic, and many cases resolve spontaneously without therapy interruption or modification, according to the Annals of Internal Medicine 10

Hepatitis C coinfection is a major risk factor for development of hepatotoxicity after antiretroviral initiation, with HAART-induced immune reconstitution being the primary mechanism, as reported by the Annals of Internal Medicine 10
Other risk factors include baseline elevated liver enzymes, alcohol abuse, and concomitant use of other hepatotoxic medications, which increase the risk of liver enzyme elevation, according to the Annals of Internal Medicine 10

The American College of Physicians notes that Biktarvy demonstrates better hepatic tolerability than older regimens, particularly nevirapine-based and ritonavir-containing protease inhibitor regimens, with a lower incidence of hepatotoxicity 10
Nevirapine has the highest risk of hepatotoxicity, with clinical hepatitis in 1.1% and potential for fulminant hepatic necrosis, as reported by the Annals of Internal Medicine 10