Pyloric stenosis


Not congenital (symptoms are not present at birth)

More common in boys (4:1)

Pylorus thickened, elongated and lumen narrowed due to hypertrophy of circular muscle

Increased incidence in 0 and B groups

Increased risk in Turner syndrome and Trisomy 18

Erythromycin or azithromycin exposure, in the first 2 weeks of life - increased incidence

Clinical features

The classical presentation is non-bilious, projectile vomiting between 2 - 8 weeks of age

Persistent vomiting à dehydration, malnutrition, hypokalemic, hypochloraemic alkalosis and paradoxical aciduria

Visible gastric peristaltic waves moving from left to right across the upper abdomen

Palpation of the pyloric tumor (olive-shaped) in the epigastrium or right upper quadrant is pathognomic

X-ray after barium meal shows string sign or double neck sign and shoulder sign

Diagnosis confirmed by USG

Persistent pyloric muscle thickness more than 3 to 4 mm

Pyloric canal length more than 15 to 18 mm in the presence of functional gastric outlet obstruction

Pyloric thickness (serosa to serosa) of 15 mm or greater

Target sign on transverse images of the pylorus

Failure of the channel to open during a minimum of 15 minutes of scanning

Retrograde or hyperperistaltic contractions

Antral nipple sign (prolapse of redundant mucosa into the antrum, which creates a pseudomass)

Double-track sign (redundant mucosa in the narrowed lumen, which creates 2 mucosal outlines)

Ramstedt’s operation (pyloromyotomy) is the treatment of choice. The hypertrophied circular muscle fibres are cut longitudinally without damaging the mucosa