TORCH test for fetal medicine indications: only CMV is necessary in the United Kingdom

To review the indications and value of TORCH testing (toxoplasma, rubella, cytomegalovirus, herpes) for fetal medicine reasons.

Analysis of all maternal and fetal TORCH tests requested from a busy Fetal Medicine Unit during nearly a 10-year period. The main ultrasound findings considered as possibly caused by congenital fetal infections were analysed. Pregnancy outcomes for cases with confirmed maternal or fetal infections were studied.

Four hundred and sixty-two maternal TORCH tests were performed. Of those, TORCH tests were also performed on fetal samples (amniotic fluid or fetal blood) in 67 cases. Fourteen fetal tests without maternal testing were identified, making the total number of patients tested 476. There were 11 cases of maternal CMV infection (2.3%), 10 cases of fetal CMV infection, and none of the other viruses. Indications for testing included fetal hyperechogenic bowel, hydrops, cerebral ventriculomegaly, echogenic foci, oligohydramnios, polyhydramnios, and IUGR. The most common findings to be actually associated with fetal infections were hyperechogenic bowel, ascites, cardiomegaly, and oligohydramnios. No cases were associated with polyhydramnious, while both IUGR and ventriculomegaly were always associated with other more relevant features.

In the United Kingdom, complete maternal TORCH testing because of fetal findings on detailed scans is often not necessary. Testing can be limited only to CMV, particularly since other infectious agents, including toxoplasmosis, are uncommon in the United Kingdom. More understanding of the relevance of the different ultrasound features to congenital infections is also important.