Fetus-in-fetu: two case reports

Abstract

The objective of our study is to describe the sonographic findings of an extremely rare pathology. We therefore present two case reports of prenatal diagnosis of fetus-in-fetu (FIF) with a review of the literature. FIF is a benign disorder, unlike the teratoma with which often enter into the differential diagnosis, localized in most cases in the retroperitoneal space. Prenatal diagnosis is based mainly on ultrasound and radiological characteristics. The treatment of choice is surgical excision. The importance of prenatal diagnosis of fetus-in-fetu and the effect on subsequent management are described.

Prenatal diagnosis of a “living” oropharyngeal fetus in fetu: a case report

“…With the advance of acoustics technology, ultrasound could be used to detect such malformation in utero. Most of cases with FIF were detected in 2nd and 3rd trimester [4]. Our case was demonstrated at 16 weeks’ gestation, the most early gestation age reported so far.…”

“…Skin, intestinal, bones, cartilage, lung, and adrenal tissue were also often present. A review [4] of reported 32 prenatal cases of FIF concluded that 90% of cases had a vertebral column, 90% had recognize bony extremity or rudimentary limb, 60% had central nervous tissue, 26% had gastrointestinal tissue, and 20% had respiratory tissue. All of reported FIF were acardiac except one case which found rudimentary heart structure by postnatal ultrasound [6].…”

“…FIF mostly located within the abdomen (80%), skull (8%) and sacral region (8%) [4]. The location of oral/ oropharyngeal was only reported in two prenatal cases [7, 8].…”

“…With the increased reports and advanced knowledge, the presence of spinal column wasn’t the necessity for diagnosis any more. The characteristics of FIF include a mass enclosed within a distinct fibrous membrane, partially or completely covered by normal skin, grossly recognizable anatomic structures and supplied by a relatively large blood vessel from the host fetus [1, 3, 4]. Moreover, the presence of grossly recognizable anatomic structures is the key point for differentiating FIF from another internal form of parasitic twin- teratoma.…”

Case report: rare congenital anomaly diagnosed by ultrasonography

“…10,11 It is usually not a malignant condition, but it can cause abdominal distension, problems during feeding, vomiting, jaundice, renal and respiratory disorders. 12 In this case, the patient presented a stable clinical picture, without physical alterations, absence of jaundice and satisfactory suction.…”