Infantile hypertrophic pyloric stenosis: data on 81 pairs of twins

Abstract

Summary87 affected twins (in 81 pairs) were identified among 3,982 children with pyloric stenosis. The proportion of twins among affected (1 in 46) is about the same as in the general population of births. The incidence of pyloric stenosis in partners of affected twins is 8.6 per cent, considerably higher than in the general population of births (0.3 per cent) but only slightly higher than in subsequent sibs (5.8 per cent).The frequency of concordance is about the same in MM (4 of 31) and MF (2 of 23) pairs. Of 39 like sexed pairs 4 were concordant; the expected number of monozygotic pairs is 18 (assuming the usual proportion of monozygotic pairs), which suggests that the frequency of concordance among them is not greater than 4 in 18. It is shown that the distribution of MM, FF and MF pairs in the series corresponds closely to the distribution expected in a twin universe which contains the usual proportions of monozygotic and dizygotic twin pairs.

Congenital hypertrophic pyloric stenosis in phenotypic female twins with X-XX mosaicism.

“…In contrast, the study of a consecutive series by MacMahon and McKeown (1955) showed no difference in concordance by zygosity, and an incidence of pyloric stenosis in one or both of twins no different from that in the general population.…”

Prevalence of infantile hypertrophic pyloric stenosis in Texas, 1999–2002

“…Mitchell and Risch (1993) published a review of the literature on genetic origins of IHPS. There are three studies on concordance of IHPS in twins (Metrokos, 1953;MacMahon and McKeown, 1955;Dodge, 1970). Among monozygotic twins the rates of concordance for IHPS ranged from a low of 27% to a high of 80%.…”

Orbital blow out fracture.

“…Evidence for a genetic component in the aetiology of pyloric stenosis was suggested by Metrakos (whose series of cases were assembled from the literature) who stated that there was a higher concordance rate of the disease in monozygotic twins than in dizygotic pairs of the same sex. In contrast, the study of a consecutive series by MacMahon and McKeown (1955) showed no difference in concordance by zygosity, and an incidence of pyloric stenosis in one or both of twins no different from that in the general population.…”