Anal atresia, vertebral, genital, and urinary tract anomalies: a primary polytopic developmental field defect identified through an epidemiological analysis of associations.

Anal atresia (AA) is observed per se or as part of different Mendelian or chromosomal syndromes, and as part of the VACTERL primary developmental field, CHARGE association, cloacal extrophy, in a mitochondrial cytopathy, and other multiple congenital anomaly patterns. There are only a few studies on the defects associated with AA, and in all of them it was observed that genitourinary defects are most frequent in infants with AA. Here we present the analysis of 28,410 malformed infants to study the frequency of 11 selected congenital defects in infants with AA in relation to their frequency in infants with multiple congenital anomaly patterns without AA. We conclude that the association of AA + spine defects + renal/urinary tract defects + genital defects constitutes a group of defects that tends to be present together in the same child because they are pathogenetically related, and since they are of blastogenetic origin they constitute a primary polytopic developmental field defect.