Abstract
Introduction
Fascioliasis is an emerging zoonotic infection in Southeast Asia, often linked to ingestion of contaminated water or aquatic plants. While many infections are asymptomatic, symptomatic fascioliasis typically presents with nonspecific abdominal pain, hepatomegaly, and peripheral eosinophilia. Large liver abscesses due to fascioliasis are rare and can mimic pyogenic or amoebic abscesses. We report a case of an unusually large liver abscess caused by fascioliasis in a young woman from eastern India, highlighting the need to consider parasitic infections in the differential diagnosis of liver lesions in endemic regions.
Case report
A 26-year old female from West Bengal presented with a 1-year history of dull, non-radiating right upper abdominal pain, accompanied by intermittent fever and unintentional weight loss of 5 kg. There was no history of jaundice, diarrhoea, cough, night sweats, comorbidity, addictions, recent travel, or animal exposure.
Examination revealed pallor without icterus nor lymphadenopathy. The liver was palpable but non-tender. Laboratory investigations showed mildly elevated C-reactive protein (10.7 mg/L), with normal white cell count, eosinophils, liver function tests, and tumour markers. Stool examination for ova and parasites and blood cultures were negative.
Contrast-enhanced CT abdomen scan revealed a multiloculated, peripherally enhancing collection with internal septations measuring 10 × 7 × 5.1 cm in the right hepatic lobe, extending to the perihepatic region and reaching the anterior abdominal wall (Fig. 1). On MRI, the lesion demonstrated restricted diffusion. Ultrasound-guided aspiration of the abscess confirmed the presence of Fasciola species on PCR, while PCR for Entamoeba histolytica was negative. Additional investigations for bacterial, anaerobic, and mycobacterial pathogens were negative, effectively ruling out these differential diagnoses. The patient was treated with two doses of triclabendazole.
Computed tomography of abdomen revealed a multiloculated, peripherally enhancing collection with internal septations extending to the perihepatic region and reaching the anterior abdominal wall. (a) Axial view and (b) coronal view.
Discussion
Human fascioliasis is a neglected tropical disease caused by F. hepatica and F. gigantica. Humans are accidental hosts, typically infected through consumption of freshwater plants such as watercress or water chestnuts contaminated with encysted metacercariae. In our case, the patient reported consuming water chestnuts, a potential source of infection.
The clinical course of fascioliasis is biphasic: an initial hepatic (acute) phase due to migration of immature flukes through the liver parenchyma, followed by a chronic biliary phase when adult worms inhabit the bile ducts. The acute phase manifests with fever, weight loss, right upper quadrant pain, jaundice, hepatomegaly, and elevated liver enzymes. The chronic phase involves biliary obstruction by adult flukes, causing colicky pain, cholecystitis, cholangitis, or pancreatitis. 1
Peripheral eosinophilia is a hallmark of the acute phase, while chronic phase is diagnosed via direct visualization of eggs on stool microscopy. Enzyme-linked immunosorbent assay-based assays are highly sensitive and specific but are often unavailable in resource-limited settings.
Typical CT findings include conglomerated hypodense rim-enhancing lesions often located in the subcapsular or peripheral region, along with serpiginous branching tracks resulting from parasite migration.2–4 Atypical radiological presentation as a large liver abscess is rare and may resemble amoebic or pyogenic liver abscesses. 5 In such cases, microbiological confirmation is essential to avoid misdiagnosis.
Triclabendazole, administered at 10 mg/kg every 12 h for two doses, is the treatment of choice for both stages. 6 Symptoms usually resolve within weeks and eosinophilia within few months, although imaging abnormalities may persist for 12–18 months. Follow-up with imaging and eosinophil counts may help monitor treatment response. 3
Footnotes
Acknowledgements
The authors acknowledge the Departments of Radiology and Parasitology for their valuable contributions and support.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. The patient understand that his name and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
