Efficacy of Diloxanide Furoate as Additional Luminal Agent Along With Metronidazole for the Treatment of Amoebic Liver Abscess

Liver abscess is a common cause of presentation to medical emergency. Among the various causes of liver abscess, Amoebic liver abscess (ALA) is a frequent cause that can resemble pyogenic infections in tropical regions. Prompt diagnosis and empirical antimicrobials along with drainage or aspiration produces successful clinical recovery.

Metronidazole has been the cornerstone of ALA therapy and achieves clinical cure in approximately 90% of uncomplicated cases (1). It is active against both luminal and tissue forms of Entamoeba histolytica, however it has relatively limited effect against the intestinal (luminal) form of parasite, so intestine may remain colonized after apparent resolution. This persistent intestinal carriage can lead to relapse or ongoing transmission (2). This prompts physicians to consider Diloxanide furoate as additional luminal agent for treatment of ALA along with metronidazole therapy.

Diloxanide furoate is traditionally administered after metronidazole to eradicate residual intestinal infection and lower relapse rates. However, many patients receive only metronidazole because of cost, limited awareness about luminal therapy, poor adherence, or absence of local comparative evidence. Studies have shown that 30-40% of patients can have inadequate luminal parasite clearance following standard metronidazole therapy for ALA (3). Frequent relapses have been seen in ALA after treatment with metronidazole (4,5). As per literature, Diloxanide furoate eradicates intraluminal cysts in approximately 85-95% of patients with non-invasive amoebiasis (6).

It remains unclear whether giving Diloxanide furoate at the same time as Metronidazole has any additional benefit compared with Metronidazole alone for patients with ALA. Theoretically, addition of diloxanide furoate could increase overall cure rate, rapid parasite clearance and reduce recurrence.

However, there is no randomized controlled trial available at present to address the research question whether dual therapy with Diloxanide furoate with Metronidazole has any added benefits in ALA. So, this randomized controlled trial has been planned to evaluate whether adding Diloxanide furoate to Metronidazole treatment improves outcomes. This study will generate robust data to formulate/modify the existing guidelines of management of ALA especially in endemic areas.

Research question:

Whether addition of Diloxanide furoate with Metronidazole is more efficacious than Metronidazole monotherapy for treatment of amoebic liver abscess in terms of achieving better clinical cure, parasitic clearance and reduced recurrence.