Hepatic paragonimiasis revealed by FDG PET/CT

Area of Science:

• Medical Imaging
• Parasitology
• Hepatology

Background:

• Fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) is a key imaging modality for detecting malignancy.
• Hepatic lesions require thorough evaluation to differentiate benign from malignant conditions.
• Paragonimus westermani is a parasitic lung fluke typically causing pulmonary infections.

Observation:

• An asymptomatic 72-year-old man presented with an incidentally detected hepatic lesion.
• FDG-PET/CT revealed increased FDG uptake in the liver lesion, raising suspicion for malignancy.
• Pathological examination identified the lesion as a granuloma caused by Paragonimus westermani.

Findings:

• The hepatic lesion, initially concerning for cancer on FDG-PET/CT, was pathologically confirmed as a granuloma.
• This represents an unusual presentation of Paragonimus westermani infection, with hepatic involvement.
• While pulmonary FDG uptake in Paragonimus westermani infections is documented, hepatic lesions are rare.

Implications:

• FDG-PET/CT findings suggestive of malignancy in hepatic lesions should consider rare parasitic etiologies.
• This case expands the known spectrum of hepatic manifestations of Paragonimus westermani.
• Awareness of unusual parasitic presentations is crucial for accurate diagnosis and appropriate patient management.