Background and study aim: Liver biopsy couldn’t be utilized
for screening of nonalcoholic steatohepatitis (NASH), as it is
considered invasive, and has many complications. The study
aims to investigate the value of serum levels of CK -18
fragments as a diagnostic biomarker for NASH and NAFLD
and its correlation with severity of NASH as measured by
NAFLD activity score (NAS) of liver biopsies. Patients and
methods: A total number of 46 subjects with biopsy-proven
non-alcoholic steatohepatitis (NASH group) and 54 subjects
with borderline NASH, simple steatosis and normal liver
tissue (non-NASH group) as well as 30 age-matched healthy
volunteers were included in the study. Scoring of liver
biopsies using the NAFLD activity score (NAS) and measurement
of CK-18 in sera was done. Results: The serum level of
cytokeratin-18 was significantly higher in the NASH group
when compared to non-NASH group (P=0.0123) or controls
(P=0.00001). Using the ROC curve, the optimal value of cytokeratin-
18 was 487U/L, with sensitivity 69 % and specificity
84.5 % in detecting NASH. Serum CK-18 levels were significantly
correlated to the disease severity as measured by liver
biopsy (degree of steatosis, fibrosis, lobular inflammation,
and ballooning) in NASH patients. Conclusions: Serum CK-
18 could be used as a non-invasive diagnostic serum marker
for patients of NAFLD and NASH.