Accuracy of sonographic criteria in the decision for surgical treatment in infantile hypertrophic pyloric stenosis

Introduction: Abdominal ultrasonography has replaced barium studies in establishing the diagnosis in difficult cases of infantile hypertrophic pyloric stenosis (IHPS). The aim of this retrospective study was to establish sonographic criteria of qualification for surgical treatment in children with IHPS. Material and methods: Hundred and fifteen infants (98 boys and 17 girls) with suspected IHPS were treated between 2000 and 2009. Pyloric muscle thickness, pyloric diameter and pyloric length were measured in US scans in all patients. Results were compared with US results of 19 infants with negative diagnosis and 29 children of the reference group. Results: Diagnosis of IHPS was confirmed by US examination in 96 children (83.5%). There were 86 boys in the group with male prevalence 8.6 : 1. The remaining 19 infants (16.5%) had a negative ultrasound. The mean PL (20.89 vs. 12.73), PMT (5.41 vs. 2.24), and PD (14.1 vs. 7.42) differed significantly between patients with and without pyloric stenosis (p < 0.0001). The mean PL (12.34), PMT (2.2), and PD (7.48) in the reference group did not differ statistically from values obtained in patients with negative IHPS diagnosis and were significantly lower than in children from the IHPS group (p < 0.0001). US imaging had a sensitivity of 98%, specificity of 100%, with a positive and negative predictive value of 100% and 90% respectively. Conclusions: This study confirmed that ultrasonography is the first choice of diagnostic method in an infant with suspected hypertrophic pyloric stenosis. In cases with an uncertain clinical diagnosis of IHPS the examination can be easily repeated.