Pyloric stenosis: evolution from pylorospasm?

Abstract

Over a 10-year period, we have performed pyloromyotomy on 260 infants with hypertrophic pyloric stenosis (HPS), 10 of whom had a history suggestive of pyloric stenosis but initially had neither the physical nor radiological findings to confirm the diagnosis. All 10 demonstrated pylorospasm on upper gastrointestinal series (UGIS), were treated medically without improvement, and subsequently developed classic HPS confirmed by repeat UGIS. Age at diagnosis ranged from 3 to 16 weeks (mean 8 weeks). Vomiting was progressively more projectile and severe from the onset until diagnosis and operation, with a duration of 5–50 days (mean 24 days). In 9 of the 10 patients a second UGIS demonstrated the diagnostic signs of HPS in 8 and suggested an antral web in the 9th. The interval between the two UGIS ranged from 2 to 46 days (mean 13 days). The 10th patient had a palpable hypertrophic pyloric muscle 9 days after the first UGIS and was operated upon without a follow-up UGIS. All 10 patients had classic HPS at operation. We conclude that although most infants with pylorospasm on UGIS improve with medical management, a small but significant number go on to develop HPS. Awareness of this variant of pyloric stenosis and appropriate follow-up UGIS will help to avoid undue delay in correctly diagnosing infants with persistent non-bilious vomiting.