What is the diagnosis and treatment for pyloric stenosis?

Diagnosis and Treatment of Pyloric Stenosis

Diagnosis

Ultrasound is the diagnostic modality of choice for hypertrophic pyloric stenosis, with definitive diagnosis requiring pyloric muscle thickness >3mm and canal length >12mm, ideally performed by a pediatric radiologist. 1, 2, 3

Clinical Presentation

• Infants present with progressive projectile nonbilious vomiting as the hallmark symptom 4, 5
• Physical examination should be performed by an experienced examiner, ideally after gastric decompression, as a distended stomach can obscure the pyloric mass 1
• The absence of a palpable "olive" mass does not exclude the diagnosis and should prompt ultrasound imaging when clinical suspicion remains high 1

Imaging Approach

• Ultrasound has 96% sensitivity and should be the first-line imaging study 2, 6
• Diagnostic ultrasound criteria include:
  • Pyloric muscle thickness >3mm (main criterion) 3
  • Pyloric canal length >12mm 3
  • Failure of the pyloric canal to relax during real-time observation 3
• Upper GI series should be reserved only for cases where ultrasound findings are equivocal or negative despite strong clinical suspicion 2
• Point-of-care ultrasound by non-radiologists remains controversial; definitive diagnosis should be confirmed by a pediatric radiologist 2

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Treatment

Pyloromyotomy is the definitive curative treatment for pyloric stenosis and should be performed after appropriate fluid resuscitation and correction of metabolic derangements. 4, 6, 5

Preoperative Management

• Fluid resuscitation and electrolyte correction are mandatory before surgery, as infants typically present with hypochloremic, hypokalemic metabolic alkalosis from persistent vomiting 4, 5
• Surgery is not an emergency—adequate time should be taken to optimize the patient's metabolic status 5

Surgical Approach

• Both open and laparoscopic pyloromyotomy are equally safe and effective, with laparoscopic approaches offering superior cosmetic results 7
• Laparoscopic pyloromyotomy demonstrates:
  • Average surgical time of 25-26 minutes 7
  • Time to full feedings of approximately 19-23 hours postoperatively 7
  • Excellent cosmetic outcomes 7
• Pyloromyotomy is curative in 100% of cases when performed appropriately 6

Postoperative Care and Complications

• Postoperative feeding can typically resume within 19-24 hours 7
• Overall complication rate is approximately 16%, with most being minor 6
• Serious complications (Clavien-Dindo grade IIIb-IVa) occur in approximately 3% of cases 6
• Mucosal perforation is the most concerning intraoperative complication and requires immediate recognition and repair 6
• Wound infection occurs in approximately 5% of cases 6
• No long-term sequelae are expected with appropriate management 6

Common Pitfalls

• Do not delay surgery for imaging if the diagnosis is clinically obvious with a palpable pyloric mass 1
• Do not proceed to surgery without adequate resuscitation—metabolic alkalosis must be corrected first 5
• Ensure complete myotomy extends adequately onto the gastric side to prevent incomplete relief of obstruction 4

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Medical Management Alternative

Medical management with atropine has been described but is not recommended as first-line therapy given the definitive cure rate and safety profile of pyloromyotomy 4, 5