Published: 2022-03-28

Fetus in fetu: a rare entity

Jaini B. Modi, Shahaji Deshmukh, Saket Jha, Apoorva Kulkarni


Fetus in fetu is a rare congenital anomaly in which a malformed fetus grows within the body of its twin. It is detected as an abdominal mass in infancy. It is a heterophagus parasite of a diamniotic, monozygotic twin. It should be differentiated from teratoma which has no axial arrangement and has got malignant potential. Although fetus in fetu is a rare condition, diagnosis using imaging can be made before surgery. It should be considered as a differential diagnosis for lump abdomen in infants. Complete excision is the treatment of choice. We present a case of a 9 years old female with fetus in fetu who was successfully managed by surgical excision.


Fetus in fetu, Teratoma, Heteropagus twins

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