Multilocular hepatic echinococcosis mimicking hepatic malignancy in a child: A diagnostic dilemma.

Multilocular (alveolar) hepatic echinococcosis is an uncommon parasitic disease that may closely resemble malignant hepatic tumors because of its infiltrative growth pattern and complex internal architecture. The condition is rare in India and is therefore frequently misdiagnosed, particularly in pediatric patients. Early and accurate diagnosis is essential, as treatment strategies differ markedly from those of hepatic malignancies and pyogenic infections. We report the case of a 13-year-old boy who presented with a four-month history of intermittent fever and right upper abdominal pain. Initial ultrasonography revealed a complex multiloculated hepatic lesion with internal septations and mass effect at the hepatic hilum, raising concern for a mesenchymal tumor. Contrast-enhanced computed tomography demonstrated a large multiloculated cystic mass with enhancing septa and peripheral walls, without solid enhancing nodules. Magnetic resonance imaging further characterized the lesion, showing T2-hyperintense cystic cavities, T2-hypointense septa, and diffusion restriction confined to the septa and peripheral walls, a pattern favoring echinococcal disease over abscess or malignancy. Serological testing confirmed hepatic echinococcosis. The patient was treated conservatively with albendazole, resulting in clinical improvement and interval reduction in lesion size on follow-up imaging. This case highlights the importance of multimodality imaging, particularly MRI with diffusionweighted sequences, in differentiating multilocular echinococcosis from malignant hepatic masses and avoiding unnecessary invasive procedures.