Interpretation of Liver Stiffness Measurement (LSM) Reduction After Antiviral Therapy
Key Principle of Interpretation
According to the EFSUMB Guidelines (Update 2017, Dietrich et al.), the diagnostic accuracy and threshold values of liver stiffness in transient elastography (TE) may differ between untreated and treated patients with chronic hepatitis B and C. This aspect should be considered when interpreting elastography results.
Even with a reduction in liver stiffness during antiviral therapy, it remains unknown whether this reflects disease regression. Therefore, changes in LSM should not influence clinical management strategies.
EFSUMB Recommendation (Update 2017)
RECOMMENDATION 25: changes in LSM during HBV therapy should not alter patient management strategy (e.g., monitoring for HCC development in at-risk patients) — LoE 2b, GOR B; strong consensus (16/0/0, 100%).
Practical conclusion: even when a decrease in stiffness indicators is recorded, HCC screening in at-risk patients should not be stopped or weakened.
Data on Fibrosis and Cirrhosis Regression
The literature cited in the fragments mentions publications on cirrhosis regression during therapy with tenofovir disoproxil fumarate for chronic hepatitis B (Marcellin P. et al., Lancet 2013) and cirrhosis regression in patients with hepatitis C with a sustained virological response after antiviral therapy (Akhtar E., Manne V., Saab S., Liver Int 2015). However, a direct link between LSM reduction and histological regression is not confirmed in the provided fragments as a basis for changing management strategies.
Technical Factors Affecting LSM on Repeated Measurement
For correct interpretation of dynamics, it is important to exclude extrahepatic causes of indicator changes. The fragments indicate that food intake affects liver stiffness: standardized food intake alters LSM in patients with HCV at different fibrosis stages (Arena U. et al., Hepatology 2013) and increases stiffness in patients with cirrhosis and portal hypertension (Berzigotti A. et al., PLoS One 2013). Therefore, the examination is performed fasting.
Conditions for Measurement Reproducibility
According to an example protocol (point SWE / ElastPQ):
- Fasting ≥ 4 hours
- Supine position, right arm behind the head
- Intercostal access, right lobe (segments V–VIII)
- Depth of the area of interest 1–3 cm from the capsule (capsule not included)
- 10 measurements, reliability criterion IQR/Med ≤ 30%
Reasons for unacceptable quality (should be indicated): obesity, ascites, cholestasis, heart failure, inflammatory episode.
Approximate Thresholds (EFSUMB, ElastPQ)
| Stage | Threshold |
|---|---|
| F0–F1 | < 7.0 kPa |
| F ≥ 2 | ≥ 7.0 kPa |
| F ≥ 3 | ≥ 9.0–9.5 kPa |
| F4 (cirrhosis) | ≥ 12.0–13.0 kPa |
Exact thresholds vary by etiology (higher in ALD and cholestasis, lower in NAFLD). Additionally, as noted above, thresholds in treated patients may differ from those in untreated patients.
Frequently asked questions
Can LSM reduction indicate fibrosis regression?
No. According to EFSUMB (Update 2017), it is unknown whether LSM reduction during therapy reflects disease regression, so such a conclusion cannot be made.
Should management strategies change with a decrease in stiffness during HBV therapy?
No. According to EFSUMB Recommendation 25 (LoE 2b, GOR B, strong consensus 100%), changes in LSM should not alter management strategies, including monitoring for HCC development.
Do LSM thresholds differ between treated and untreated patients?
Yes. According to EFSUMB (Update 2017), the accuracy and threshold values of TE may differ between untreated and treated patients with hepatitis B and C; this is considered in interpretation.
What technical factors distort repeated LSM measurement?
Food intake increases liver stiffness (Arena 2013; Berzigotti 2013), so measurements are performed fasting ≥ 4 hours. Quality is also reduced by obesity, ascites, cholestasis, heart failure, inflammatory episode.
What is the reliability criterion for measurement in point SWE?
IQR/Med ≤ 30% with 10 successful measurements (according to the ElastPQ working protocol).