By Will Boggs, MD
NEW YORK (Reuters Health) Nov 28 - A simple strategy incorporating platelet counts, ultrasound (US) exam, and liver stiffness (LS) measurements can identify early portal hypertension in asymptomatic patients with liver disease, researchers from Spain report.
"Simple, non-invasive procedures (lab, US, LS) are good enough for prognostic stratification and management of patients with compensated cirrhosis," said Dr. Salvador Augustin from Hospital Universitari Vall d'Hebron in Barcelona.
"Complex indexes or formulas are not needed. Aggressive, expensive procedures (hepatic venous pressure gradient (HVPG), upper endoscopy) should be reserved for high-risk patients only," he told Reuters Health by email.
Several studies have shown that liver stiffness measured by transient elastography correlates well with invasive HVPG measurements, but it remains unclear whether the diagnostic performance of transient elastography can be translated to clinical settings.
Dr. Augustin and colleagues evaluated the feasibility and accuracy of a systematic strategy based on simple parameters and LS measurements for identifying early-stage (i.e., without high-risk varices) portal hypertension in a prospective, longitudinal, observational study of 250 patients with asymptomatic chronic liver disease.
Among these patients, 173 (69%) had normal platelets and ultrasound (group A), 49 (20%) had low platelets and normal ultrasound (group B), and 28 (11%) had low platelets and abnormal ultrasound (group C), according to findings published online November 7 in the Journal of Hepatology.
LS measurements could not be obtained from 22 patients (9%). Three-quarters of the remaining patients (174/228, 76%) had LS values below 13.6 kPa, and 54 patients (24%) had values at or above the "normal" cutoff of 13.6 kPa.
Significantly more patients in group C (81%) than in group A (8%) had abnormally high levels of LS.
Upper endoscopy identified esophageal varices in 10 of 49 patients (20%) with elevated LS values (none of them high-risk), and significantly more patients in group C (43%) than in group B (6%) or group A (0%) had varices.
Only two of 30 patients with LS values below 25 kPa had varices, the researchers note.
Of the 40 patients who underwent HVPG measurement after upper endoscopy, 37 (93%) had portal hypertension and 26 (65%) had clinically significant portal hypertension.
According to post-hoc analyses, the use of 25 kPa as an LS cutoff would allow clinicians to confidently rule in the presence of clinically significant portal hypertension.
"In patients with very high LS (above 25), cirrhosis and clinically significant portal hypertension are almost 100% certain," Dr. Augustin said. "These patients are clearly at higher risk of developing a complication of their liver disease in the short-midterm (40% at 4-5 years)."
"With current available treatment strategies, that would imply performing an upper endoscopy and treat if high-risk varices are found (i.e., primary prophylaxis)," he added. "If ongoing studies prove that drug therapy (beta-blockers) prevent decompensation when given before the development of varices (i.e., pre-primary prophylaxis), in the very near future these patients could be prescribed a simple drug empirically, based exclusively on non-invasive procedures."
For patients with low LS, Dr. Augustin said, "The prevalence of cirrhosis in these patients has been consistently proven to be almost zero. In addition, liver disease progresses very slowly at this compensated stage. I would recommend, based on available evidence and experience, regular outpatient visits once a year, with routine lab & ultrasound workup and a liver stiffness measurement. That would be more than enough. Performance of upper endoscopy for screening of esophageal varices at this stage is not justified."
Dr. Augustin noted that three-quarters of the patients were hepatitis C positive, so the new findings would need validation in patients with different etiologies.
Dr. Hiromitsu Hayashi, who was not involved in the study, said that the three-pronged strategy "enables us to avoid the redundant endoscopy and invasive procedure (HVPG measurement), and results in clinical and economic benefits."
Based on prior work by his group, "we recommend the use of clinical parameters, such as serum bile acid and ammonia, which reflect the formation of porto-systemic shunt, in patients with low LS," Dr. Hayashi, from Kumamoto University's department of gastroenterological surgery in Japan, told Reuters Health by email.
Dr. Hayashi agreed with Dr. Augustin that "high LS is a major risk factor of development of varices. In such a patient, endoscopy should be performed to evaluate the varices."
J Hepatol 2013.
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