Case of fetus in fetu

Abstract

Fetus-in-fetu is a rare developmental anomaly resulting from abnormal embryogenesis in a monochorionic diamniotic pregnancy, where vestigial remnants of a nonviable fetus are enclosed within a normally developing fetus. We report a case of a 4-year-old male presenting with abdominal pain for three days. Imaging studies, including ultrasound and computed tomography (CT), revealed an intra-abdominal mass with features consistent with fetus-in-fetu. Surgical excision confirmed the diagnosis, supported by histopathological examination, which identified the mass as a highly differentiated teratoma. This case highlights the diagnostic value of imaging techniques like CT and ultrasound in identifying fetus-in-fetu.