A New Screening Strategy for Varices
Condition: Liver Cirrhosis
MeSH terms: Liver Cirrhosis
Study type: Observational

Summary: 
      Liver cirrhosis is an advanced stage of chronic liver diseases, which is often associated
      with various complications, namely esophageal and/or gastric varices, ascites, hepatocellular
      carcinoma (HCC). It is well known that the risk of complications varies even among cirrhotic
      patients, as those with more advanced disease would have more complications and poorer
      survival rates. Liver stiffness measurement (LSM) with transient elastography is found useful
      to identify cirrhotic patients with higher risk of portal hypertension and presence of
      varices . Recently, spleen stiffness measurement (SSM) with the same machine was found
      accurate to predict portal hypertension and esophageal varices.

      Investigators hypothesized that a new screening strategy guided by LSM and SSM (LSSM) values
      (LSSM-guided) is non-inferior to conventional strategy in terms of detection rate of
      clinically significant esophageal and/or gastric varices for patients with liver cirrhosis in
      an open-labeled randomized controlled trial.

      Consecutive patients with compensated liver cirrhosis will be invited for the study. Patients
      fulfilling the study criteria will be randomized into LSSM arm (upper endoscopy only
      performed to patients with high LSM or SSM values), and control arm (upper endoscopy
      performed to all patients). Patients randomized into LSSM arm will undergo transient
      elastography examination; those with high LSM or SSM results will be referred for upper
      endoscopy examination for to screen varices. Patients randomized into control arm will be
      directly referred for upper endoscopy examination.
    

Detailed description: 
      Liver cirrhosis is an advanced stage of chronic liver diseases, which is often associated
      with various complications, namely esophageal and/or gastric varices, ascites, hepatocellular
      carcinoma (HCC). It is well known that the risk of complications varies even among cirrhotic
      patients, as those with more advanced disease would have more complications and poorer
      survival rates. Liver stiffness measurement (LSM) with transient elastography is found useful
      to identify cirrhotic patients with higher risk of portal hypertension and presence of
      varices at cross-sectional basis. LSM cutoff values of 17.6 kPa and 21.0 kPa would have the
      sensitivity ≥ 90% in order to detect patients with hepatic venous pressure gradient (HVPG)
      above 10-12mmHg , while the presence of varices could be confidently excluded with a liver
      stiffness below 12.5-19.8 kPa. However, these suggested cutoff values overlap with those for
      detecting histologic cirrhosis in most chronic liver diseases. Hence there seems no
      significant additional information provided by LSM regarding screening endoscopy for varices
      among cirrhotic patients.

      Recently, spleen stiffness measurement (SSM) with the same machine was found accurate to
      predict portal hypertension and esophageal varices. An SSM cutoff value <41.3 kPa is
      sensitive and seems able to accurately rule out the presence of varices. This supports a
      possible screening strategy, reserving upper endoscopy only for patients with an SSM
      ≥41.3kPa.
    

Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Subjects will be recruited from the medical clinics of Prince of Wales Hospital and Alice
        Ho Miu Ling Nethersole Hospital. Patients with known chronic liver diseases, radiological
        evidence of liver cirrhosis and compensated liver function will be invited.