Normal liver stiffness and its determinants in healthy blood donors.
BACKGROUND
Several studies in healthy populations have investigated normal liver stiffness on transient elastography, but none has excluded subjects with fatty liver.


OBJECTIVE
To define normal liver stiffness and its determinants in 923 healthy voluntary blood donors with and without fatty liver.


METHODS
Seven hundred and forty six subjects were analyzed with transient elastography according to the absence (602) or presence of fatty liver (144) at ultrasonography. The cut-off for significant fibrosis was a liver stiffness of 7.9kPa.


RESULTS
Normal subjects had significantly lower liver stiffness (median 4.4kPa) than fatty liver subjects (median 5.3, p<0.001). In normal livers male gender was significantly associated with increased liver stiffness at multiple linear regression analysis. Nine (1.4%) blood donors with normal liver and 9 with fatty liver (6.2%) had >7.9kPa. Subjects with verified liver stiffness >7.9kPa, were further investigated with liver biopsy or non-invasive fibrosis markers: only 1 patient with fatty liver had >F1 fibrosis.


CONCLUSIONS
Liver stiffness in normal liver is lower than in fatty liver, and gender is the only influencing variable. Transient elastography has a very low false positive rate for significant fibrosis and may have a role in screening populations at risk for liver disease.
Colombo
Silvia
S
Hepatology Unit, Treviglio Hospital, Treviglio, Bergamo, Italy.
Belloli
Livio
L
Zaccanelli
Maurizio
M
Badia
Elisabetta
E
Jamoletti
Carlo
C
Buonocore
Marco
M
Del Poggio
Paolo
P
D000328:Adult; D000368:Aged; D001706:Biopsy; D001782:Blood Donors; D004548:Elasticity; D054459:Elasticity Imaging Techniques; D005234:Fatty Liver / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology / Q000502:physiology*; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors; D055815:Young Adult