Positive Methacetin Breath Test Predicts Poor Survival in Chronic Viral Hepatitis
By Megan Brooks
Medscape Medical News
November 16, 2009 (Boston, Massachusetts) — The 13C methacetin breath test (MBT; BreathID, Exalenz Bioscience Ltd) can be used to accurately predict long-term survival in patients with chronic viral hepatitis and might serve as an adjunctive tool to the Model for End-Stage Liver Disease (MELD) system.
That's according to the results of a 395-patient clinical trial reported during a plenary session here at The Liver Meeting 2009: American Association for the Study of Liver Diseases (AASLD) 60th Annual Meeting.
During his presentation, study investigator Beat Mullhaupt, MD, from the Department of Gastroenterology and Hepatology at University Hospital Zurich in Switzerland, said that "impaired liver function picked up by this test could help us in evaluating our patients."
The 395 patients with chronic viral hepatitis in the study performed the breath test after ingesting 75?mg of methacetin. Eighty percent of patients had a MELD score below 10. The average age of study subjects was 46 years, roughly two thirds were male, and most had hepatitis?C virus infection. Patients were followed for up to 2 years.
An MBT survival score, which includes age and MBT parameters, was used to predict mortality. According to the investigators, with each log unit increase in survival score, the risk for death was increased by 32% (hazard ratio, 1.32; 95% confidence interval, 1.18?- 1.48; P?< .0001).
Patients who died with a MELD score below 15 were correctly identified as being at risk by the MBT survival score. Of the 395 patients, 11 died during follow-up; the breath test identified 9 of the 11 as being at high risk. "Importantly, 6 of the 11 deaths occurred in patients with a MELD score below 15," Dr. Mullhaupt and colleagues report.
Conversely, there were no deaths in patients identified as low risk by the MBT survival score, despite MELD scores as high as 23.
AASLD president Scott L. Friedman, MD, chief of liver diseases at Mount Sinai Medical Center in New York CIty, said: "What's interesting about this study is that there were actually patients who had what would be considered a relatively low MELD score. That is, we would think they had pretty stable liver function and yet, when this more subtle test of liver function was performed, some patients actually?.?.?. ended up having decreased survival."
"The implication of this study," Dr. Friedman told reporters, "is that there is now a technology, if it is validated, that can discriminate between patients who have apparently well-preserved liver functioning and yet have a higher risk of succumbing to liver failure."
"This, along with other technologies, really represents a new generation of effort to diagnose liver disease at earlier stages?.?.?. and predict who is at risk for decompensation without having to wait for more advanced disease," he added.
Dr. Mullhaupt has disclosed no relevant financial relationships. Dr. Friedman has participated in advisory committees or review panels for Exalenz.
The Liver Meeting 2009: American Association for the Study of Liver Diseases (AASLD) 60th Annual Meeting: Abstract 96. Presented November?2, 2009.
