Pyloric Stenosis

Epidemiology

• • 0.1-0.4% incidence

  • 7% incidence among children of affected parent

  • 4:1 ratio male:female

  • Higher incidence in first born

Symptoms and Signs

• • Nonbilious postprandial emesis 2-12 weeks of life becoming progressively projectile

  • Palpable pylorus in right upper quadrant or epigastric region ("olive")

  • Visible or palpable gastric peristaltic waves

Laboratory Findings

• • Transient unconjugated hyperbilirubinemia in 1-2% of cases

  • Hypokalemic, hypochloremic, metabolic alkalosis

Imaging Findings

• • US: Shows hypertrophic pylorus, 95% sensitive

  • Upper GI: Shows narrowed and elongated pylorus, 95% sensitive

• • Repeated nonbilious vomiting in early infancy may be due to the following:

  • -Overfeeding

    -Intracranial lesions

    -Pylorospasm

    -Antral web

    -Gastroesophageal reflux

    -Pyloric duplication

    -Duodenal stenosis

    -Malrotation of the bowel

    -Adrenal insufficiency

• • History and physical exam

  • Serum electrolytes

  • Abdominal x-ray

  • US of abdomen if diagnosis in doubt

  • Upper GI if diagnosis still in doubt

Surgery

• • Laparoscopic or open pyloromyotomy

Indications

• • Normalization of serum electrolytes

  • Persistent vomiting

Medications

• • Volume resuscitation and correction of chloride to at least 90 mEq/L and CO2 to less than 30 mEq/L

Treatment Monitoring

• • Serum electrolytes before surgery

Complications

• • Duodenal or gastric injury

  • Incomplete myotomy (recurrent gastric outlet obstruction)

Prognosis

• • Excellent

References