Overview
Pyloric stenosis describes the narrowing of the pylorus (the opening from the stomach to the small intestine) caused by hypertrophy and hyperplasia of the smooth muscle surrounding it. It occurs in infants aged 2-8 weeks.
Epidemiology
- Its incidence is around 5 per 1,000 live births per year
- 4 times more common in males
- Around 10% of infants may have a family history
- More common in first-born male infants
Presentation
The key feature of pyloric stenosis is forceful ‘projectile’ non-bilious vomiting around 30 minutes after a feed:
- The baby remains hungry
- The vomiting may not start off as projectile but increase in intensity until it does
- Constipation and dehydration may be present
- A right upper quadrant or epigastric mass may be felt
Investigations
- Blood gases and electrolytes:
- May show hypochloraemic hypokalaemic metabolic alkalosis
- Ultrasound abdomen:
- The test of choice
- Shows increased pyloric muscle thickness
Differential Diagnoses
Gastro-oesophageal reflux (GOR)
- Regurgitation is not forceful and effortless
- Blood gases and electrolytes are normal
Management
- Ramstedt’s pyloromyotomy is the surgery of choice
Complications
- Vomiting can lead to dehydration, weight loss, and electrolyte disturbances
Prognosis
- The prognosis is very good with early diagnosis and treatment
