Ethnically and anthropometrically diverse healthy subjects and patients with liver disease demands investigations regarding liver stiffness measure (LSM) to derive an acceptable normal range. 

A study thus performed LSM by transient elastography (TE) using FibroScan.

• 437 healthy subjects with normal alanine aminotransferase (ALT) levels and 274 patients with liver disease including 188 with nonalcoholic fatty liver disease (NAFLD) and 86 with chronic hepatitis of viral and other etiologies were enrolled for the study.
• 125 patients underwent Liver biopsy. 
• A normal value for LSM, as described by the 5th percentile was 3.2 kPa and the 95th percentile was 8.5 kPa in healthy subjects. 
• Healthy subjects with a lower body mass index (BMI; < <18.5 kg/m2) demonstrated higher LSM than subjects having a normal BMI; this LSM value was similar to obese subjects (6.05 ± 1.78 versus 5.51 ± 1.59 and 6.60 ± 1.21, respectively). 
• Liver disease patients without histological fibrosis demonstrated substantial higher LSM values (7.52 ± 5.49) than healthy subjects (5.63 ± 1.64). 
• Stage of fibrosis was the only histological variable, which was a predictor for LSM.  
• NAFLD and chronic hepatitis groups did not show an association of LSM with inflammatory activity and ALT. 

Thus the range of LSM was established between 3.2 and 8.5 kPa in healthy subjects of South Asian origin. Higher LSM values were demonstrated in lean and obese healthy subjects than in subjects with normal BMI. Also, initiation and progression of Liver stiffness even before the occurrence of fibrosis in patients with liver disease was demonstrated.

SOURCE-

Das K, Sarkar R, Ahmed SM, Mridha AR, Mukherjee PS, Das K et al. “Normal” liver stiffness measure (LSM) values are higher in both lean and obese individuals: A population-based study from a developing country, Hepatology, 2012;55(2):584-593. https://doi.org/10.1002/hep.24694