Hepatitis B and Liver Elastography: 2024 WHO Guidelines Explained | Elastography Australia

Chronic hepatitis B (CHB) affects an estimated 220,000+ Australians, with significantly higher rates in communities with heritage from endemic regions — including much of East and Southeast Asia, sub-Saharan Africa, and the Pacific.

For years, liver biopsy was the reference standard for staging fibrosis in CHB patients. The 2015 WHO guidelines introduced non-invasive tests (APRI and transient elastography) as alternatives. In 2024, those guidelines were substantially updated — with new elastography thresholds that make liver stiffness measurement more central to treatment decisions than ever before.

What Changed in the 2024 WHO Guidelines

The 2024 WHO hepatitis B treatment guidelines introduced new non-invasive test thresholds that reflect an updated meta-analysis of fibrosis staging accuracy. The key changes for elastography:

• Significant fibrosis (≥F2): liver stiffness >7 kPa now supports treatment recommendation, regardless of HBV DNA or ALT level.

• Cirrhosis (F4): liver stiffness >12.5 kPa supports a cirrhosis diagnosis based on clinical criteria.

The guidelines broadened treatment eligibility — treatment is now recommended for any adult or adolescent with evidence of significant fibrosis or cirrhosis, removing prior restrictions on HBV DNA and ALT thresholds that had excluded many patients from treatment.

These changes were informed by a 2024 systematic review and meta-analysis published in The Lancet Gastroenterology & Hepatology, which found transient elastography more accurate than APRI for both significant fibrosis and cirrhosis diagnosis in CHB patients.

Elastography vs APRI in CHB — Why Elastography Wins

In a hypothetical population of 1,000 unselected CHB patients with 25% prevalence of significant fibrosis:

• APRI at >0.5 cutoff: 262 false positives, 68 false negatives.

• Elastography at >7 kPa cutoff: 158 false positives, 63 false negatives.

Elastography produces significantly fewer false positives — which matters in a clinical context where a false positive may lead to unnecessary treatment, and a false negative may leave a patient undertreated.

Comparative accuracy data also favours 2D shear wave elastography (2D-SWE) over vibration-controlled transient elastography (VCTE) in CHB populations. A 2018 study comparing 402 CHB patients found 2D-SWE achieved an AUC of 0.87 vs 0.80 for VCTE — a meaningful difference when staging patients for treatment decisions.

The Australian CHB Context

Australia's hepatitis B burden is unevenly distributed. High-prevalence communities are concentrated in major metropolitan areas — particularly Melbourne, Sydney, and Brisbane — but regional centres with significant migrant populations also carry high CHB burden.

Many CHB patients in Australia are inadequately monitored. Barriers include:

• Under-recognition of CHB status in primary care.

• Incomplete understanding of the new WHO guidelines and updated treatment thresholds.

• Limited access to elastography — particularly outside major city centres.

• Language and cultural barriers in affected communities.

The 2024 guidelines create an opportunity to identify and treat more CHB patients who meet the new staging thresholds. But only if accurate elastography is available at the point of care.

Practical Implications for Australian Clinicians

For GP practices serving high-prevalence CHB communities:

• Screen for CHB status in all patients from endemic regions if not already documented.

• Calculate FIB-4 (or APRI) from routine blood results for all CHB patients in monitoring.

• For CHB patients with liver stiffness assessment: use the updated 7 kPa threshold for significant fibrosis and 12.5 kPa for cirrhosis when making treatment referral decisions.

• Refer for elastography for any CHB patient with indeterminate FIB-4 or where treatment eligibility is uncertain.

For practices offering in-house elastography, CHB monitoring represents a stable, recurring scan population — typically one scan every 12–24 months per monitored patient, depending on fibrosis stage and treatment status.