Evaluation and improvement of a reliable diagnosis of cirrhosis by blood tests.

Objective: To evaluate the rates of reliable diagnosis of cirrhosis by two usual blood tests.

Methods: Reliable diagnosis was mainly evaluated by comparing rates of positive (PPV) and negative (NPV) predictive values with FibroTest and FibroMeters, as either standard test or specifically designed for cirrhosis, in 1056 patients with chronic hepatitis C.

Results: Using the diagnostic limits provided by fibrosis stage scales, the PPV for cirrhosis was: standard FibroMeters: 68.5% versus FibroTest: 37.1%. Using 95% PPV, the cirrhosis detection rate was: specific FibroMeter: 26.1% versus FibroTest: 2.0% (P<10(-3)). The cirrhosis detection rate increased from 26 to 65% by performing liver biopsy in 8% of patients with indeterminate results on specific FibroMeter between 95% NPV and PPV. On the other hand, specific FibroMeter provided three intervals of 95% reliable diagnosis with no biopsy: less than or equal to 95% NPV: no cirrhosis (threshold: diagnosis); significant fibrosis; and greater than or equal to 95% PPV: cirrhosis.

Conclusion: The detection rate and PPV for cirrhosis using fibrosis scales were fair for standard FibroMeter and poor for FibroTest. Around one-fourth of cases of cirrhosis are detected by the 95% PPV of specific FibroMeter, and around two-thirds by performing an additional liver biopsy in only 8% of patients. Finally, specific FibroMeter can avoid liver biopsy by classifying patients into three categories: no cirrhosis; significant fibrosis; and cirrhosis.