Validating controlled attenuation parameter in the assessment of hepatic steatosis in living liver donors

Abstract

Introduction Hepatic steatosis (HS) negatively impacts transplant outcomes in living liver donors. To date, liver biopsy is preferred for HS evaluation. This study aims to evaluate the measurement of controlled attenuation parameter (CAP) as a diagnostic tool of HS in living liver donors. Methods Candidates recruited to this study, conducted from April 2016 to February 2020, were potential donors who had undergone transient elastography using Fibroscan® and CAP measurements at liver segments VI and VII, followed by liver biopsy. The HS grades from liver biopsy were classified as S0 (<5%), S1 (5–33%), S2 (33–66%), and S3 (>66%). For CAP, they were S0 (≤218dB/m), S1 (218-249dB/m)), S2 (250-305dB/m)), and S3 (>305dB/m)). The CAP measurements were compared with the liver biopsy results. Results Of the 150 potential donors [male, 73.3%; mean age, 30.0±7.0 years; body mass index (BMI), 24.7±3.5kg/m2], 92 (61.3%) had no or mild HS, while 58 (38.7%) and 10% had moderate to severe HS based on CAP and liver biopsy, respectively. Subjects with moderate to severe HS per CAP were mostly males (0.014), and had higher BMI (p = .006), alanine aminotransferase (ALT) (.001), gamma-glutamyl transferase (.026), and high-density lipoprotein (.008). On multivariate analysis, high ALT (OR, 1.051; 95% CI, 1.016–1.087; p = .004) was a predictor of significant HS. The sensitivity, specificity, positive and negative predictive values of CAP to detect significant HS were 93.3%, 67.4, 24.1%, and 98.9%, respectively. Conclusion The high sensitivity and negative predictive values of CAP make it a good screening test to exclude significant HS in potential living liver donors which, in turn, can help avoid unnecessary liver biopsies.

Characterization of hepatic steatosis using controlled attenuation parameter and MRI‐derived proton density fat fraction in living donor liver transplantation

“…ing 150 LLD, found an AUROC of .88 for the detection of steatosis (significant or any degree) with CAP, yielding a sensitivity of 87% and specificity of 84% at a cut off value of 276 dB/m. 22 In a retrospective study of 56 healthy potential donors, CAP detected moderate-severe steatosis with an AUROC of .88 (sensitivity 83%, specificity 82% for a cutoff value of 276 dB/m, P < .001). 24 Another study of 54 potential liver donors found even greater accuracy, demonstrating an AUROC of .96 (sensitivity 100%, specificity 89% for a cutoff value of 257 dB/m, P < .001) in detecting any degree of steatosis.…”

“…There are a few similar studies from the Middle East and East Asia which have shown comparable results. The largest study, including 150 LLD, found an AUROC of .88 for the detection of steatosis (significant or any degree) with CAP, yielding a sensitivity of 87% and specificity of 84% at a cut off value of 276 dB/m 22 . In a retrospective study of 56 healthy potential donors, CAP detected moderate‐severe steatosis with an AUROC of .88 (sensitivity 83%, specificity 82% for a cutoff value of 276 dB/m, P < .001) 24 .…”

“…Mean BMI in donors selected for the M-probe was 26 ± 4 kg/m 2 versus 30 ± 3 kg/m 2 (P = .001) in those chosen for the XL-probe. The IQR/median was 13%(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23) and 98 (97%) had an IQR/median ≤30%. Importantly, out of the three patients with an IQR/median >30%, only one had a liver stiffness above 7.1 kPa (stiffness was 7.3 kPa), and thus, all but one measurement (100/101; 99%) were considered to be reliable.Accuracy of donor CAP to detect any degree of steatosis, defined by MRI-PDFF ≥6.4%, showed an AUROC curve of .94 (95% CI .90-.99; Figure2).…”

“…20 Although the optimal detection thresholds for CAP measurements have yet to be defined and accuracy is limited in obese patients and subsets of chronic liver disease, 21 its performance has not been studied in healthy candidates undergoing evaluation for LLD in the Western world. [22][23][24] Given that variations in body frame and overall prevalence of chronic medical conditions across race/ethnic groups affect the accuracy and thresholds for detecting liver disease with transient elastography and CAP, [23][24][25][26][27][28] it is important to have accessible data on the performance of these techniques for the LLD population in the United States.…”

Current Understanding of Marginal Grafts in Liver Transplantation

“…With the increasing incidence of obesity and nonalcoholic fatty liver disease (NAFLD), the global prevalence of liver steatosis has risen among organ donors [42]. Currently, the main methods employed to evaluate hepatic steatosis include gross visual recognition, imaging analysis [43], controlled attenuation parameter (CAP) [44], and biopsies [45]. Steatotic donor livers (SDLs), defined as livers with severe steatosis (≥30% fat content), have emerged as a new source for expanding the donor pool.…”