Case 66: Caudal Regression Syndrome in the Fetus of a Diabetic Mother

Abstract

A 21-year-old pregnant woman with an 18-year history of type I diabetes mellitus was referred for a full fetal ultrasonographic (US) examination at 22 weeks gestation (Figs 1-4). Results of a prior US examination at 10 weeks gestation confirmed a single live intrauterine pregnancy; however, crown-rump length was found to be similar to that of a fetus 1 week 2 days younger than expected by last menstrual date. In addition, magnetic resonance (MR) imaging was performed to help assess fetal anatomy (Figs 5-7). IMAGING FINDINGSUS images of the fetal head demonstrated normal intracranial anatomy. In particular, the lateral ventricles and posterior fossa appeared normal (Fig 1), and biometric measurements of the head were normal for gestational age. The ossified elements of the spine were not depicted below the midlumbar region (Fig 2). The fetal legs were extended and clearly separate, and they exhibited reduced soft tissue and possessed a normal number of bones. The right foot had an abnormal orientation (Fig 3). Of note, the legs did not move during the course of the 30-minute examination, and the length of the femora was similar to that of a fetus 1 week younger than Part 1 of this case appeared 4 months previously and may contain larger images. ). © RSNA, 2004 Figure 1. Transabdominal US images of the head of the fetus at 22 weeks gestation. (a) The ventricles (V) and (b) the cerebellum (C) and cisterna magna (arrow) are of normal size and appearance. There is no Arnold-Chiari malformation. 229

Caudal Regression Syndrome: A Case Series of a Rare Congenital Anomaly

“…Ultrasound is also helpful in evaluating other associated anomalies such as renal anomalies including agenesis, cystic dysplasia and caliectasis, and gastrointestinal anomalies such as duodenal atresia [4]. Fetal MRI can also be used to make the diagnosis in difficult cases [5].…”

Prenatal diagnosis of caudal regression syndrome without maternal diabetes mellitus

“…The relationship and interdependence of developing caudal nervous, spinal, hindgut, and mesonephric elements involved in the closure of the neural tube result in the development of neural, distal vertebral, anorectal, renal, and genital abnormalities that produce CRS. However, structures that are developmentally distant from these caudal elements, such as the brain, proximal spine, and spinal cord, are not generally involved in CRS (2). Caudal regression syndrome is a rare disease and the true pathogenesis is unclear.…”

“…This results in motor and sensory deficits of the lower extremities. Cardiac diseases, gastrointestinal disorders, neutral tube defects, and genitourinary malformations may accompany CRS (2). Although uncontrolled maternal diabetes, genetic predisposition and vascular hypoperfusion are the possible risk factors, the actual pathogenesis is unclear (3).CRS is generally diagnosed during prenatal assessment, but also a varying number of newborns with some degree of anomaly may be presented.…”

Pictorial Essay: Infants of diabetic mothers

“…On the other hand, sacral agenesis or caudal regression syndrome (CRS) [Figure 4], which is the congenital defect thought to be most characteristic of diabetic embryopathy, is seen 200 to 400 times more frequently in IDMs;[7] diabetes must be ruled out in mothers who give birth to infants with sacral agenesis. [8] CRS is also known as caudal dysplasia sequence and is characterized by a series of congenital anomalies[9] [Table 2]. Sirenomelia is considered by some to be an extreme form of the CRS, though the single umbilical, persistent vitelline artery in sirenomelia differentiates the two.…”