Synonyms: congenital hypertrophic pyloric stenosis, hypertrophic pyloric stenosis
This condition is caused by diffuse hypertrophy and hyperplasia of the smooth muscle of the antrum of the stomach and pylorus. It usually occurs in infants aged 2-8 weeks. The pyloric muscle hypertrophy results in narrowing of the pyloric canal, which can then become easily obstructed. Genetic studies have identified susceptibility loci for infantile hypertrophic pyloric stenosis (IHPS) and molecular studies have concluded that smooth muscle cells are not properly innervated in this condition.
- Add notes to any clinical page and create a reflective diary
- Automatically track and log every page you have viewed
- Print and export a summary to use in your appraisal
- It occurs in 1 in 500 live births.
- It is more common in males than in females, with reported ratios ranging from 2:1 to 5:1.
- First-born male children are believed to have the highest risk.
- Hypertrophic pyloric stenosis (HPS) occurs very rarely in adults and must then be differentiated from gastric cancer.
- Typical presentation is onset of vomiting at 2-8 weeks old but late presentation up to 6 months can occur:
- Vomiting increases in frequency over several days.
- Vomiting also increases in intensity until it becomes projectile.
- Slight haematemesis may occur.
- Persistent hunger, weight loss, dehydration, lethargy, and infrequent or absent bowel movements may be seen.
- Stomach wall peristalsis may be visible.
- An enlarged pylorus, classically described as an 'olive', can usually be palpated in the right upper quadrant or epigastrium of the abdomen:
- With the infant supine and the examiner on the child's left side, gently palpate the liver edge near the xiphoid process.
- Then displace the liver superiorly; downward palpation should reveal the pyloric olive just on, or to the right of, the midline.
- It should be possible to roll the pylorus beneath the examining finger.
- Feeding problem or milk intolerance.
- Gastro-oesophageal reflux.
- Duodenal atresia, oesophageal atresia or other bowel obstruction in the newborn.
- Intestinal malrotation.
- Acute midgut volvulus.
- Serum electrolytes (for correction of imbalances before surgical repair); there is often metabolic alkalosis with severe potassium depletion.
- Ultrasound is reliable and easily performed and has become the main investigation. Imaging is not required if an experienced examiner is able to palpate an 'olive'.
- Although ultrasound is most often performed, one study found upper gastrointestinal barium series to be more cost-effective than ultrasound because fewer secondary studies were required.
- A further advantage of a barium study is that it can identify other possible diagnoses such as gastro-oesophageal reflux.
- Preoperative management is directed at correcting the fluid deficiency and electrolyte imbalance.
- Ramstedt's pyloromyotomy is easily performed and is associated with minimal complications.
- Laparoscopic pyloromyotomy is also performed and is an effective alternative where suitable facilities are available. Time to achieve full enteral feeding has been found to be significantly shorter (18.5 hours) in those treated laparoscopically vs those having open pyloromyotomy (23.9 hours).
- Double-Y pyloromyotomy has also been safely and effectively performed.
- Vomiting can lead to dehydration, weight loss, and severe electrolyte disturbance with hypokalaemic, hypochloraemic metabolic alkalosis.
- Operative complications include mucosal perforation, continued postoperative bleeding (very rare), and persistent vomiting due to incomplete pyloromyotomy (rare).
- Foveolar cell hyperplasia (FCH) has been reported as a rare cause of persistent gastric outlet obstruction in patients with infantile hypertrophic pyloric stenosis (HPS). An extended pyloromyotomy is required to manage this.
- Prognosis is excellent unless diagnosis is delayed and prolonged severe dehydration occurs.
- Mortality is rare after pyloromyotomy.
Further reading & references
- Panteli C; New insights into the pathogenesis of infantile pyloric stenosis. Pediatr Surg Int. 2009 Dec;25(12):1043-52. Epub 2009 Sep 16.
- Hellan M, Lee T, Lerner T; Diagnosis and therapy of primary hypertrophic pyloric stenosis in adults: case report and review of literature. J Gastrointest Surg. 2006 Feb;10(2):265-9.
- Graadt van Roggen JF, van Krieken JH; Adult hypertrophic pyloric stenosis: case report and review.; J Clin Pathol. 1998 Jun;51(6):479-80.
- Infantile hypertrophic pyloric stenosis, Surgical Tutor
- White MC, Langer JC, Don S, et al; Sensitivity and cost minimization analysis of radiology versus olive palpation for the diagnosis of hypertrophic pyloric stenosis.; J Pediatr Surg. 1998 Jun;33(6):913-7.
- Hulka F, Campbell JR, Harrison MW, et al; Cost-effectiveness in diagnosing infantile hypertrophic pyloric stenosis.; J Pediatr Surg. 1997 Nov;32(11):1604-8.
- Aspelund G, Langer JC; Current management of hypertrophic pyloric stenosis. Semin Pediatr Surg. 2007 Feb;16(1):27-33.
- van der Bilt JD, Kramer WL, van der Zee DC, et al; Laparoscopic pyloromyotomy for hypertrophic pyloric stenosis: impact of experience on the results in 182 cases. Surg Endosc. 2004 Jun;18(6):907-9. Epub 2004 Apr 27.
- Hall NJ, Pacilli M, Eaton S, et al; Recovery after open versus laparoscopic pyloromyotomy for pyloric stenosis: a Lancet. 2009 Jan 31;373(9661):390-8. Epub 2009 Jan 18.
- Alalayet YF, Miserez M, Mansoor K, et al; Double-Y pyloromyotomy: a new technique for the surgical management of infantile Eur J Pediatr Surg. 2009 Feb;19(1):17-20. Epub 2009 Feb 16.
- Tan HL, Blythe A, Kirby CP, et al; Gastric foveolar cell hyperplasia and its role in postoperative vomiting in Eur J Pediatr Surg. 2009 Apr;19(2):76-8. Epub 2009 Feb 25.
- Nazer H et al; Pediatric Hypertrophic Pyloric Stenosis, Medscape, Mar 2012
|Original Author: Dr Colin Tidy||Current Version: Dr Hayley Willacy|
|Last Checked: 21/01/2011||Document ID: 1455 Version: 22||© EMIS|
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.