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Caudal regression syndrome

Other Names for this Disease
  • Caudal dysplasia
  • Caudal regression sequence
  • Sacral agenesis
  • Sacral agenesis syndrome
  • Sacral regression syndrome
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What is caudal regression syndrome?

What are the signs and symptoms of caudal regression syndrome?

What causes caudal regression syndrome?

What is caudal regression syndrome?

Caudal regression syndrome is a rare birth defect that impairs the development of the lower (caudal) half of the body.[1] The condition may affect the lower back (including the spinal cord) and limbs, the genitourinary tract, and the gastrointestinal tract.[1] The severity of this condition varies among affected individuals. The cause of caudal regression syndrome is not known, but it may be related to maternal diabetes, genetic factors, and blood blockages (vascular hypoperfusion).[2][3][4]
Last updated: 9/25/2012

What are the signs and symptoms of caudal regression syndrome?

The signs and symptoms of caudal regression syndrome vary depending on the severity of the condition.

Some individuals have incomplete closure of the vertebrae around the spinal cord; a fluid-filled sac on the back covered by skin that may or may not contain part of the spinal cord; or tufts of hair at the base of the spine. Curvature of the spine (scoliosis) may also be present. The spinal abnormalities can affect the size and shape of the chest, which may cause breathing problems.

Individuals may have small hip bones and a flat and dimpled buttocks. The leg bones are often underdeveloped. Other features may include clubfeet or calcaneovalgus; decreased sensation in the lower limbs; and/or various abnormalities of the genitourinary tract. In severe cases, affected individuals may have a lack of development of the genitalia (genital agenesis). Gastrointestinal abnormalities may include abnormal twisting (malrotation) of the large intestine; an obstruction of the anal opening (imperforate anus); or inguinal hernias. Constipation and loss of bladder and bowel control are common.[1]
Last updated: 9/25/2012

What causes caudal regression syndrome?

In many cases, the underlying cause of caudal regression syndrome (CRS) remains unclear.[5] It is thought to be a multifactorial disorder, which means that multiple factors (genetic and environmental) likely interact to predispose an individual to being affected.[1]

Up to 22% of cases of CRS are associated with diabetes mellitus in the mother during pregnancy.[1][5] However, CRS also occurs in infants of non-diabetic mothers. There is ongoing research to identify other factors that may increase the risk of CRS, as well as the proportion of cases attributable to these factors.

Some researchers believe there is a disruption of mesoderm development in the fetus, which impairs the normal formation of parts of the skeleton, gastrointestinal system, and genitourinary system.[1] Others have suggested it may result from the presence of an abnormal artery in the abdomen, which diverts blood flow away from the lower areas of the developing fetus.[1] It may also be caused by a combination of these.[1] Inconclusive studies have implicated that some teratogens may play a role in CRS.[5]

The varieties of malformations, the numerous organ systems involved, and the lack of presence of identical abnormalities in subsequent pregnancies have generally not supported the notion that there is a specific genetic cause of CRS.[5] However, one case of an affected girl with a mutation in the VANGL1 gene has been reported.[6]
Last updated: 9/28/2012

  1. Caudal regression syndrome. Genetics Home Reference. January 2012; Accessed 9/25/2012.
  2. Boulas MM. Recognition of caudal regression syndrome. Adv Neonatal Care. 2009 Apr;
  3. Bohring A. Caudal Regression Syndrome. National Organization for Rare Disorders: Guide to Rare Disorders. Philadelphia, PA: Lippincott Wiliams & Wilkins; 2003;
  4. Samartzis D, Shen FH. Caudal regression syndrome. Ann Acad Med Singapore. 2008 May;
  5. Boulas MM. Recognition of caudal regression syndrome. Adv Neonatal Care. April 2009; 9(2):61-69.
  6. SACRAL DEFECT WITH ANTERIOR MENINGOCELE. OMIM. January 11, 2012; Accessed 9/25/2012.
  7. Sylvie Odent. Caudal regression sequence. Orphanet. April 2010; Accessed 9/25/2012.