Definition

An area of the fetal bowel with homogenous echogenicity equal to that of the surrounding bone.

Explanation

The reason for this appearance has yet to be elucidated and is likely to be multi factorial to reflect the different associations. It has been attributed to altered meconium composition (1), bowel wall ischaemia (2) and swallowed blood (3). The incidence is 0.2-0.6%.

Standard image for identification/exclusion

The echogenicity should be at least equal or greater than that of surrounding bone. There should be no shadowing or enhancement to confuse the appearances. The bowel must appear echogenic in transverse and longitudinal sections of the abdomen.

Technique for measurement/assessment

Implications of a positive finding in isolation

These cases must be reviewed by a Consultant Obstetrician with experience in Fetal Medicine. They are complex and may require referral to Fetal Medicine Centres (4).

Echogenic bowel with other signs of placental failure will require further growth/liquor/Doppler assessment.

Karyotyping should be considered by the Consultant reviewing the case.

Cystic fibrosis (CF) should be considered and parental blood taken for carrier status to identify couples at risk. If amniocentesis is taken for chromosome analysis CF studies can be requested. Any DNA analysis will only detect known mutations, currently 85% of clinical cases. All babies born in the UK are screened for CF after birth.

Blood should be taken for TORCH screen and parvovirus serology.

Image 2 - Echogenic Bowel

 

References

1. Nyberg DA, Dubinsky T, Resta RG, Mahony BS, Hickok DE, Luthy DA. Echogenic fetal bowel during the second trimester: clinical importance. Radiology 1993; 188: 527-31, Abstract

2. Ewer AK, McHugo JM, Chapman S, Newell SJ. Fetal echogenic gut: a marker of intrauterine gut ischaemia? Arch Dis Child 1993; 69: 510-3, Abstract

3. Sepulveda W, Hollingsworth J, Bower S, Vaughan JI, Fisk NM. Fetal hyperechogenic bowel following intra-amniotic bleeding. Obstet Gynecol 1994; 83:947-50, Abstract

4. Sepulveda W, Sebire NJ, Fetal echogenic bowel: a complex scenario. Ultrasound Obstet Gynecol. 2000; 16: 510-514, Abstract

5. Sepulveda W, Nicholaides P, Mai AM, Hassan J, Fisk NM. Is isolated second-trimester hyperechogenic bowel a predictor of suboptimal fetal growth? Ultrasound in Obstetrics & Gynecology. 1996;7(2):104-7, Abstract

6. Nyberg DA, Souter VL, El-Bastawissi A, Young S, Luthhardt F, Luthy DA. Isolated sonographic markers for detection of fetal Down syndrome in the second trimester of pregnancy. J Ultrasound Med 2001 Oct; 20(10): 1053-63, Abstract

7. Al-Kouatly HB, Chasen ST, Streltzoff J, Chervenak FA. The clinical significance of fetal echogenic bowel. Am J Obstet Gynecol 2001 Nov; 185(5): 1035-8, Abstract