Prenatal Diagnosis of Body Stalk Anomaly in the First Trimester of Pregnancy
By Tsirka, Aspasia; Korkontzelos, Ioannis; Diamantopoulos, Pantelis; Tsirkas, Panagiotis; Stefos, Theodoros
Anterior abdominal wall defects expressed as three basic types (omphalocele, gastroschisis and body stalk complex) are in general diagnosed during the second trimester of pregnancy . The body stalk anomaly is characterized by the presence of a major abdominal wall defect, severe kyphoscoliosis, a rudimentary umbilical cord (short or monoarterial), neural tube defects, genitourinary malformations, anomalies of the chest wall, intestinal atresia, limb deformities, and craniofacial defects . We report herein a case of body stalk anomaly diagnosed at 12 weeks of gestation.
A 30-year-old woman, primigravida, was referred for a nuchal translucency (NT) scan at 12 weeks of gestation. The medical history was insignificant and no use of medication was reported. We used transabdominal and transvaginal scans for detailed examination. We noticed a live fetus with crown-rump length (CRL) 52.4 mm, compatible with gestational age according to last menstrual period. The NT measurement was 2.8 mm. The lower part of the embryo was placed in the coelomic cavity and the skin of the abdominal wall defect was continuous with the amniotic membrane, which appeared intact (Figure 1). The anterior abdominal wall defect contained bowel and liver. The umbilical cord was short with a single artery. There was anencephaly, cleft lip and palate, and severe kyphoscoliosis. The left forearm was short and the left hand had three fingers. The left shinbone was hypoplastic. The right shinbone was also hypoplastic and the foot was missing. After counseling the patient opted to terminate the pregnancy and an uncomplicated surgical procedure was performed.
At autopsy, the sonographic findings were verified. In addition, exophthalmos of the right eye and absence of the left one were found. Part of the left lung and of the heart protruded out of the thoracic cavity (Figure 2).
Body stalk anomaly is a rare, sporadic and fatal developmental abnormality presenting in monochorionic and dichorionic twin pregnancies and in singleton pregnancies [2,3]. Monozygotic twins seem to be more vulnerable to this abnormality with an incidence of 12.5% . Body stalk anomaly is usually diagnosed by ultrasound in the second trimester, but recent data present a trend to establish early diagnosis in the first trimester with a reported incidence of one in 7500 pregnancies . Furthermore, it appears that the use of ultrasound screening in the first trimester is becoming more comprehensive. Extra-abdominal viscera extruding from a major abdominal wall defect is the primary ultrasonographic sign. Other abdominal wall defects together with rare syndromes such as Cantrell’s pentalogy, Beckwith-Wiedemann syndrome and OEIS complex (omphalocele-exstrophy-imperforate anus-spinal defects) have to be excluded . The NT is usually increased, but karyotyping by invasive procedure is not routinely performed since it is expected to be normal.
The etiology of body stalk anomaly cannot be explained by only one theory. The first theory suggested that early rupture of the amnion induces the creation of fibrous bands from the chorionic surface and causes direct mechanical pressure inducing lesions on the fetal body [1,5]. Van Alien et al. suggested that early generalized compromise of embryonic blood flow during the first six weeks of gestation leads to failure of closure of the ventral body wall and persistence of the extra-embryonic coelomic cavity . The most accepted theory is that of abnormal embryonic folding . During the fifth week of gestation, the flat trilaminar embryo is transformed into a cylindrical fetus by a parallel set of four contiguous body folds (cephalic, caudal and lateral axes). If maldevelopment occurs it will result in the group of anomalies mentioned before such as Cantrell’s pentalogy (abnormal cephalic folding), omphalocele (lateral defect) or cloacal exstrophy (caudal defect) .
Figure 1. Large abdominal wall defect containing liver and bowel. This section also shows the skull-brain defect.
Figure 2. Postmortem appearance after termination.
Body stalk anomaly is a lethal malformation and early diagnosis is essential. Careful counseling is necessary in cases where there is a twin pregnancy with only one affected fetus where the management should be focused on the unaffected fetus. In singleton pregnancies termination of the pregnancy should be strongly advised. In the case reported herein, the membranes appeared intact, thus early amniotic rupture should not be considered the main cause of the defect in this case. Although definite data are still unavailable, it seems that amniotic band syndrome with body wall defects and body stalk anomaly present different expressions of the same developmental abnormality.
1. Ginsberg NE, Cadkin A, Strom. Prenatal diagnosis of body stalk anomaly in the first trimester of pregnancy. Ultrasound Obstet Gynecol 1997; 10:419-421.
2. Kahler C, Humbsch K, Schneider U, Seewald HJ. A case report of body stalk anomaly complicating a twin pregnancy. Arch Gynecol Obstet 2003;268:245-247.
3. Paul C, Zosmer N, Jurkovic D, Nicolaides K. A case of body stalk anomaly at 10 weeks of gestation. Ultrasound Obstet Gynecol 2001;17:157-159.
4. Daskalakis G, Sebire NJ, Jurkovic RM, Snijders RJ, Nicolaides KH. Body stalk anomaly at 10-14 weeks of gestation. Ultrasound Obstet Gynecol 1997; 10:416-418.
5. Torpin R. Amniochorionic mesoblastic fibrous strings and amnionic bands: Associated constricting fetal malformations or fetal death. Am J Obstet Gynecol 1965;91:65-67.
6. Van Alien M, Curry C, Gallagher L. Limb-body wall complex. 1. Pathogenesis. Am J Med Genet 1987;28:529-548.
7. Duhamel B. Embryology of exomphalos and allied malformations. Arch Dis Child 1963;38:142-147.
ASPASIA TSIRKA1, IOANNIS KORKONTZELOS2, PANTELIS DIAMANTOPOULOS1, PANAGIOTIS TSIRKAS2, & THEODOROS STEFOS3
1 Hippocrates Clinic, Agrinio, Greece, 2 Department of Obstetrics and Gynecology, State General Hospital of Ioannina “G. Chatzikosta”, Ioannina, Greece, and 3 Department of Obstetrics and Gynecology, University Hospital of Ioannina, Ioannina, Greece
(Received 2 June 2006; revised 2 August 2006; accepted 17 November 2006)
Department of Obstetrics and Gynecology
State General Hospital of Ioannina “G. Chatzikosta”
Tel: +30 2651077166
Copyright Taylor & Francis Ltd. Feb 2007
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