Infantile pyloric stenosis is the most common condition requiring surgical intervention in the first year of life. It typically presents in infants 2 to 6 weeks after birth. Clinically the disorder is characterized by projectile vomiting, visible gastric ... Infantile pyloric stenosis is the most common condition requiring surgical intervention in the first year of life. It typically presents in infants 2 to 6 weeks after birth. Clinically the disorder is characterized by projectile vomiting, visible gastric peristalsis, and a palpable pyloric tumor (summary by Everett et al., 2008). Mortality was high until successful treatment by pyloromyotomy was developed by Ramstedt (1912). - Genetic Heterogeneity of Infantile Hypertrophic Pyloric Stenosis Multiple susceptibility loci have been implicated in IHPS including IHPS1 on chromosome 12q, IHPS2 (610260) on chromosome 16p13-p12, IHPS3 (612017) on chromosome 11q14-q22, IHPS4 (300711) on chromosome Xq23, and IHPS5 (612525) on chromosome 16q24.
The etiologic role of the NOS1 gene (163731) on chromosome 12q in infantile pyloric stenosis was investigated by analysis of 2 intragenic polymorphisms, NOS1a and NOS1b, in 27 families by Chung et al. (1996). They found significant overall ... The etiologic role of the NOS1 gene (163731) on chromosome 12q in infantile pyloric stenosis was investigated by analysis of 2 intragenic polymorphisms, NOS1a and NOS1b, in 27 families by Chung et al. (1996). They found significant overall transmission disequilibrium between pyloric stenosis and NOS1a (P = 0.006). Consideration of each allele independently revealed a significant tendency for preferential transmission of allele 7 (210 bp) to the affected offspring (P = 0.006). Chung et al. (1996) suggested that NOS1 is a susceptibility locus for pyloric stenosis. Findings leading to a contradictory conclusion were reported by Soderhall and Nordenskjold (1998), who could find no linkage between infantile hypertrophic pyloric stenosis and NOS1 in 3 Swedish families with multiple affected members. For these studies they used the AAT motif repeat in the first intron of the NOS1 gene. Saur et al. (2004) studied molecular mechanisms by which NOS1 gene expression is altered in pyloric tissues of 16 German infants with IHPS and 9 German controls. In IHPS patients, a significantly decreased expression of total NOS1 mRNA was found by quantitative RT-PCR; the decrease affected predominantly exon 1c, with a reduction of 88% compared with controls. Expression of exon 1f was increased significantly, indicating a compensatory upregulation of this NOS1 mRNA variant. Studying DNA samples of the 16 IHPS patients and 81 controls for mutations and SNPs in the NOS1 exon 1c promoter, Saur et al. (2004) found that carriers of the A allele of the exon 1c promoter -84G-A SNP (163731.0001) had increased risk of development of IHPS (odds ratio, 8.0). In contrast, Lagerstedt-Robinson et al. (2009) found no association between dbSNP rs41279104 and infantile hypertrophic pyloric stenosis among 82 Swedish patients and 80 controls. The frequency of the A allele in the control group was 29%.
The incidence of infantile pyloric stenosis was estimated to be between 1 and 5 per 1,000 live births in Britain (Davison, 1946; Dodge, 1975).
There is a striking variation in incidence between population groups, with the ... The incidence of infantile pyloric stenosis was estimated to be between 1 and 5 per 1,000 live births in Britain (Davison, 1946; Dodge, 1975). There is a striking variation in incidence between population groups, with the cumulative incidence in American infants being 1.9 per 1,000 live births in whites, 1.8 in Hispanics, 0.7 in blacks, and 0.6 in Asians (Schechter et al., 1997).