Poorly absorbable antibiotics do not affect hepatic venous pressure gradient

Neither rifaximin nor norfloxacin, both poorly absorbable antibiotics, significantly reduces hepatic venous pressure gradient (HVPG) in patients with portal hypertension and cirrhosis, a recent study has found.

Researchers performed a meta-analysis of five studies retrieved from online databases, such as Medline, Embase, and Scopus. Only randomized controlled trials were considered for inclusion. Those without baseline or follow-up HVPG measurement were ineligible. Three of the included studies had a high risk of bias. The pooled sample included 215 patients.

Meta-analysis found a nonsignificant drop in HVPG after treatment with norfloxacin or rifaximin (mean difference [MD], –0.55 mm Hg; 95 percent confidence interval [CI], –1.52 to 0.42; p=0.27), suggesting that the antibiotics had no effect on HVPG. Moderate heterogeneity of evidence was found: two studies reported a significant reduction, one saw an effect of borderline significance, and the remaining two saw no change.

Subgroup analysis according to therapy duration found that longer duration of antibiotic treatment, lasting for 60–90 days, resulted in a significant decrease in HVPG (p=0.01), in comparison to regimens of just up to 30 days.

Disaggregating according to the type of antibiotics did not reveal important differences. Rifaximin led to a nonsignificant drop in HVPG (MD, –1.56 mm Hg; p=0.11), which was only nominally greater in magnitude than norfloxacin (MD, –0.29; p=0.57).

“[A]dequately powered randomized controlled trials comparing longer-term rifaximin plus nonselective beta-blockers (NSBB) to NSBB alone would be required to guide clinical decision-making in this field, and it remains unclear whether compensated or decompensated patients (with ascites) with cirrhosis are the ideal candidate,” researchers said.