More information on the sensitivity of ultrasonography for detecting fatty liver is available in the setting of living-related liver transplantation (Transplantation 2013; 95: DOI: 10.1097/TP.0b013e31828d1588).
In this study the authors retrospectively examined the degree of steatosis from 492 living liver donors who had normal ultrasounds and normal aminotransferase levels. The median age of the donors was 30.1 year and the median BMI was 22.4 kg/meter-squared.
Background: According to the authors, if liver histology shows severe macrosteatosis (>60%), transplantation is canceled. Furthermore, in cases of moderate macrosteatosis (30-59%), the risks/benefits need to be considered on an individual basis due to increased risk of mortality; Spitzer et al (reference below) demonstrated that macrovesicular steatosis >30% was an independent predictor of reduced 1-year graft survival. In addition, a previous report has indicated that both macrosteatosis and microsteatosis had similar impacts on postoperative liver function.
- 3 (0.6%) had severe total steatosis, moderate or greater steatosis was diagnosed in 4 (0.8%) for macrosteatosis, in 26 (5.3%) for microsteatosis, and 56 (11.4%) for total steatosis.
- There were two identified risk factors BMI >23 kg/meter-squared and triglycerides >88 mg/dL. Individuals with both risk factors had a 28.6% prevalence of moderate or greater degree of total steatosis compared with 6.6% with no risk factors. In these individuals, a liver biopsy may be worthwhile.
Why this study matters for the non-transplant physician: This study provides additional data that ultrasonography is not adequate to exclude significant degrees of fatty liver.
Study limitations included the retrospective analysis which relied on medical record accuracy, degree of steatosis was not based on a single pathologist, ultrasonography was not based on not based on a single radiologist, both BMI and triglycerides may vary based on age, gender, ethnicity and other factors.
Related blog entries:
- A liver disease tsunami | gutsandgrowth
- NAFLD Guidelines 2012 | gutsandgrowth
- Pediatric NAFLD Position Paper | gutsandgrowth
- -Spitzer AL et al. Liver Transpl 2010; 16: 874-84.
- -Liver Transpl 2013; 19: 437-49. Difficulty with precisely determining steatosis
- -Hepatology 2011; 54: 1082. U/S w ~85% sensitivity in detecting fatty liver.
- -Gastroenterol 2008; 135: 1961. Liver biopsy (in pediatrics) still needed as surrogates not accurate for correlating degree of fibrosis/injury.
- -J Pediatr 2009; 155: 469. Review. No evidence-based guidelines for treating in pediatrics –main Rx wt loss/exercise. Consider obtaining ultrasound.