Abstract:
Statement of the problem:
Pakistan falls in the intermediate prevalence zones for HCV infection.
Steatosis frequently affects the natural history of HCV infection and
causes diagnostic confusion with fibrosis on ultrasound evaluation of
liver.
Objectives:
To determine the accuracy of ultrasound in diagnosis, severity
grading and differentiation of steatosis from fibrosis in patients
with HCV not responding to standard therapy of interferon and
Ribavarin using histopathology as gold standard;
To compare the clinical, hematological and biochemical features
between those with steatosis(S) and those without steatosis (NS).
Methods:
Patients with HCV not responding to Ribavarin-conventional
interferon therapy were evaluated, from March 2008-August 2010 with
ultrasound for detection and grading of steatosis and fibrosis using a
standardized set of criteria. They later underwent liver biopsy,
haematology, and serum biochemistry evaluation for detection of
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significant differences in S and NS groups. Statistical analysis was
done on SPSS 19 using Chi square, t- test, ANOVA and Spearman
correlation as applicable with significance at p>0.05. Sensitivity,
specificity, negative and positive predictive values for ultrasound
were determined using histopathology as the gold standard.
Results:
The overall accuracy for detection of steatosis was 95.39% and that for fibrosis was
98.02%. The specificity of ultrasound for diagnosing and grading the
hepatic steatosis was 90.9% for no steatosis, 100% for both gross and moderate
steatosis and 95.9% for mild steatosis. The specificity for fibrosis was 100%
for no fibrosis, 96.07% for mild fibrosis, 89.18% for moderate fibrosis and 97.05%
for gross fibrosis. Hepatic vein showed increased dampening of flow with
advancing grades of steatosis and fibrosis. Mean BMI, serum Alanine
transferase and serum Gamma GT levels were significantly higher and
platelets were markedly lower among group S than the NS group. The
rest of the clinical, sonographic and laboratory features were not
markedly different.
Conclusions:
Ultrasound has a high accuracy in the diagnosis and grading of
steatosis and fibrosis in HCV patients not responding to standard
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Ribavarin and interferon therapy. Presence of mild fibrosis can hide
the presence of mild to moderate steatosis acting as a confounder.
However reliable distinction is achievable in the more advanced
grades of the condition despite coexistence.