Caudal mesoderm pattern of anomalies: from renal agenesis to sirenomelia.

Abstract

AbstractThe use of 6168 unselected malformed infants, obtained from the Swedish Register of Congenital Malformations during the years 1965–1971, made possible an analysis of a complex of malformations that form a series from the Potter syndrome to sirenomelia. A total of 73 infants belonging to this group were identified among the approximately 550,000 births — an incidence of 1/7500 births. They formed a series from infants with the typical Potter syndrome to typical sirenomelia. Analysis of the association of various malformations indicated til at pulmonary hypoplasia and “Potter face” are not only an effect of oligohydram‐nios. A mesodermal damage is postulated as the cause of the complex of malformations. A variable craniocaudal extension of the damage can explain the different expressions of the syndrome. Closure defects of the central nervous system, facial clefts, and congenital heart defects were less common than expected when compared with other infants with multiple malformations. The incidence of these infants born in Sweden has apparently increased over the years. There was also an apparent preponderance of them in central Sweden. Pregnancies ending with the birth of infants with this malformation complex began during summertime more often than could be expected. No exogenous cause was identified.