Two major patterns of nongenetic malformations are found at autopsy

Second study on the recurrence risk of isolated esophageal atresia with or without trachea-esophageal fistula among first-degree relatives: no evidence for increased risk of recurrence of EA/TEF or for malformations of the VATER/VACTERL association spectrum

BACKGROUND

Esophageal atresia with/without trachea-esophageal fistula (EA/TEF) denotes a spectrum of severe congenital malformations. The aim of this systematic study was to determine both the recurrence risk for EA/TEF, and the risk for malformations of the VATER/VACTERL association spectrum, in first-degree relatives of patients with isolated EA/TEF.

METHODS

A total of 108 unrelated patients with isolated EA/TEF were included. These individuals had 410 first-degree relatives including 194 siblings. The presence of EA/TEF and malformations of the VATER/VACTERL association spectrum in relatives was systematically assessed. Data from the EUROCAT network were used for comparison.

RESULTS

None of the first-degree relatives displayed any form of EA/TEF. In two families, a first-degree relative presented with malformations from the VATER/VACTERL association spectrum. However, no increase in the risk for malformations of the VATER/VACTERL association spectrum was found compared with the control cohort (p = 0.87). In three families, one more distantly related relative presented with EA/TEF.

CONCLUSION

In contrast to previous studies, our results suggest a very low recurrence risk for isolated EA/TEF and/or for malformations of the VATER/VACTERL association spectrum among first-degree relatives.

Nine new twin pairs with esophageal atresia: a review of the literature and performance of a twin study of the disorder

BACKGROUND

Isolated esophageal atresia (EA) is a rare congenital malformation whose etiology remains largely unknown. Nine twin pairs with EA were identified from our clinical service, prompting the performance of a systematic review of the literature and the first reported twin study of isolated EA.

METHODS

A total of 330 twin pairs with EA were identified from the literature. The zygosity, concordance, and malformation (isolated vs. nonisolated) status of all 339 twin pairs were evaluated. A total of 72 twin pairs (4 of 9 / 68 of 330) fulfilled the criteria for inclusion in a classic twin study of isolated EA.

RESULTS

The pairwise concordance rates were 50% (95% confidence interval [CI], 34-66%) for monozygous (MZ) twin pairs and 26% (95% CI, 15-42%) for dizygous (DZ) twin pairs (p = 0.033). The probandwise concordance rates were 67% (95% CI, 53-78%) for MZ twin pairs and 42% (95% CI, 29-56%) for DZ twin pairs (p = 0.011). The MZ/DZ ratios were 1.9 for pairwise analysis and 1.6 for probandwise analysis. The familial risk ratios for MZ and DZ twin pairs were 1700 and 900, respectively.

CONCLUSION

The observation of higher concordance rates for MZ compared to DZ twin pairs indicates that genetic factors contribute to isolated EA.