Impact of prenatal diagnosis of fetus-in-fetu

The First Case of Fetus in Fetu in Nicaragua: The Management Experience of the Pediatric Neurosurgery Team

Fetus in fetu (FIF) is a rare congenital anomaly of asymmetric monozygotic twins, where the parasitic twin develops abnormally inside the body of the host twin. In most cases, it is incorporated into the sibling's abdomen, which frequently presents as a retroperitoneal mass. Currently, at least 200 cases have been reported worldwide, being this the first case in Nicaragua. We describe a case of a male newborn, born via cesarean section, with a history of multiple congenital malformations observed via ultrasound examination. At birth, a mass is observed on its dorsum that impresses a skull, but without the presence of bones, with three limbs, two upper and one lower, with an outline located transversely on the pelvic girdle and the presence of two male genitalia with agenesis of the testicles and an accessory kidney. A preoperative diagnosis of FIF and spinal dysraphism was made by computed tomography (CT) and magnetic resonance imaging (MRI). They shared a spinal cord and had the presence of an open spinal defect type meningocele with aberrant roots. After the diagnosis and discussion, the multidisciplinary team proceeded to surgery to perform the separation of the twin (FIF). The subsequent anatomopathological examination revealed that the fetus was anencephalic and had reliable FIF characteristics. The resection was performed followed by the closure of the 430 mL meningocele and complete separation of the spine and the parasitic twin. We present the first case of fetus in fetu in Nicaragua.

A cohort of five cases with asymmetric conjoined twining and literature review

PURPOSE

Asymmetric conjoined twining (ACT) is a form of conjoined twining which is a rare malformation of monochorionic monoamniotic twin pregnancy. Most publications were single case reports. We reported a cohort of five cases with ACT from a single tertiary medical center and reviewed the case reports of ACT over the last decade to enrich the clinical research of this disease and summarized the clinical features of the disease.

METHODS

We reviewed five cases of ACT admitted in Tianjin Children's Hospital from 17 March, 2008, through 7 March 2017. The cohort was analysed from general information, imaging manifestations, separation surgery, histopathological findings, outcome and follow-up. We searched the English literatures on case reports of ACT over the past decade from the PubMed database and presented details about the clinical characteristics, treatment, and prognosis of all cases.

RESULTS

There were four males and one female in our cohort. Among the five cases, two parasites were located in epigastrium, two in rachis, and one in retroperitoneum (fetus in fetu, FIF). All of the parasites were separated successfully by operation in five cases and were confirmed to be ACT by histopathology reports. Four patients made an uneventful recovery except for one case of wound infection. All of them were doing well in follow-up. In the literature review, we found 41 cases of exoparasitic heteropagus twining (EHT) and 63 cases of FIF.

CONCLUSIONS

ACT is very rare and usually diagnosed by prenatal ultrasonography (US). Computed tomography (CT) and magnetic resonance imaging (MRI) examinations are essential imaging examinations before separation surgery to delineate the anatomical relationship between the autosite and the parasite. In general, the separation surgery of ACT is less complicated and the prognosis is better compared with the symmetric conjoined twining (SCT).

Rare Fetus-in-Fetu: Experience From a Large Tertiary Pediatric Referral Center

Objective: Fetus-in-fetu (FIF) is an extremely rare disease, and most prior publications are single case reports. Here, we describe the clinical characteristics, imaging manifestations, and the treatment and related complications of FIF from a large tertiary pediatric referral center. Materials: After institutional review board approval, patients with a diagnosis of FIF between January 2010 and November 2019 were further selected and reexamined. We analyzed the general clinical characteristics, imaging manifestations, treatment, and prognosis of the patients. Results: A total of seven (four male and three female) patients with FIF were included in the study. All patients were diagnosed with FIF during the antenatal ultrasound examination along with an abnormal increase in alpha fetoprotein, and it was confirmed by subsequent pathological examination. The median gestation period when FIF was first diagnosed was 25 (range: 22-32) weeks. Ultrasound, computed tomography, and magnetic resonance imaging were the main pre-operative diagnostic techniques used. All patients underwent FIF resection within 1 month after birth: four patients had open surgery and three had laparoscopic surgeries (one case was converted to open surgery); only one patient developed ascites after surgery. All patients are growing up healthy and without tumor recurrence at the last follow-up. The level of alpha fetoprotein decreased to normal within 1 year (range 3-10 months) after surgery performed. Conclusion: As the size of the FIF increases, it can be found and diagnosed in antenatal ultrasound examination. Surgery is an important curative treatment for FIF and generally results in excellent long-term quality of life.

Fetus-in-fetu: two case reports

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.