Annual Physical Exam Management for HBsAg-Reactive Patient on Tenofovir 300mg
Continue tenofovir 300mg daily and implement structured monitoring with HBV DNA and ALT every 3-6 months, plus annual HCC surveillance if indicated by age and ethnicity. 1
Essential Laboratory Monitoring
Check the following labs at this annual visit:
- HBV DNA by PCR – This is the single most critical test to confirm viral suppression (target: undetectable or <69 IU/mL) 2, 1
- ALT/AST – Monitor for hepatic inflammation and treatment response 2, 1
- Serum creatinine and calculated creatinine clearance – Tenofovir requires renal monitoring every 3 months in at-risk patients, but at minimum every 12 weeks for all patients 2
- Serum phosphorus – Monitor every 3 months in patients at risk for renal toxicity 2
- Quantitative HBsAg – Annual testing to assess for potential functional cure (HBsAg loss) 1
- HBeAg/anti-HBe status (if initially HBeAg-positive) – Check every 6 months to monitor for seroconversion 2
Hepatocellular Carcinoma Surveillance
Initiate or continue ultrasound screening every 6 months if the patient meets any of these criteria: 1
- Asian men >40 years or Asian women >50 years
- Any patient with cirrhosis
- Age >40 years with persistent ALT elevation
- Family history of HCC
This surveillance continues indefinitely, even with undetectable HBV DNA on treatment 1.
Verify Treatment Adherence and Efficacy
At 8 years of tenofovir treatment, 98-99.6% of patients should have undetectable HBV DNA 2. If viral suppression is not achieved:
- First, assess medication adherence – Virologic breakthrough with tenofovir is rare and usually indicates nonadherence 2, 3
- Check for drug-drug interactions (particularly with antidepressants like venlafaxine, paroxetine, or other medications that may affect absorption) 3
- If adherence is confirmed and breakthrough persists, perform genotypic resistance testing, though no resistance to tenofovir has been documented through 10 years of treatment 2, 4, 5
Coinfection Screening (if not previously done)
Screen for the following if not already completed: 1
- Anti-HCV antibody
- Anti-HDV antibody (especially if history of injection drug use)
- Anti-HIV antibody
- Anti-HAV antibody – If negative, vaccinate against hepatitis A as coinfection increases mortality 5.6- to 29-fold 1
Ongoing Treatment Considerations
Do not discontinue tenofovir without careful consideration 6. The optimal duration of treatment for chronic hepatitis B is unknown, and the relationship between treatment response and long-term prevention of hepatocellular carcinoma is not established 6. For most patients, indefinite treatment is recommended 1.
Severe acute exacerbations of hepatitis can occur after discontinuation in HBV-infected patients 6. If discontinuation is considered, ALT levels must be monitored at least monthly for the first 3 months, then every 3 months thereafter 2.
Special Circumstances Requiring Immediate Action
If the patient will undergo chemotherapy or immunosuppressive therapy:
- Continue tenofovir prophylaxis throughout treatment and for at least 12 months after cessation (24 months for rituximab-based regimens) 2, 1
- Monitor HBV DNA every 6 months during antiviral therapy 2
Preventive Counseling
Reinforce the following at each visit: 6
- Complete alcohol abstinence – Even limited consumption worsens outcomes 1
- Avoid sharing needles, razors, or toothbrushes
- Practice safer sex with barrier protection
- Do not breastfeed (tenofovir is excreted in breast milk) 6
Common Pitfalls to Avoid
Do not attribute virologic breakthrough solely to resistance – With tenofovir's high barrier to resistance, nonadherence or drug interactions are far more likely causes 2, 3. Do not delay HCC surveillance – Screening should begin immediately for high-risk patients and continue indefinitely regardless of viral suppression 1. Do not monitor less frequently than recommended – The 2015 Clinical Gastroenterology and Hepatology guidelines specify HBV DNA every 12-24 weeks and liver panel every 12 weeks as minimum monitoring 2.