Tests and diagnosis
By Mayo Clinic staffSigns and symptoms of pyloric stenosis can mimic those of other conditions that cause infant vomiting, including gastroesophageal reflux disease (GERD). Your baby's doctor may use various steps to make the diagnosis:
- Physical exam. Your baby's doctor may feel an olive-shaped lump — the enlarged pyloric muscle — when examining your baby's abdomen.
- Blood tests. The loss of electrolytes — such as sodium, potassium, magnesium and calcium — may be a sign of continual vomiting and dehydration.
- Ultrasound. This test uses sound waves to create an image of your baby's stomach.
- Contrast X-ray. For this test, your baby swallows a small amount of a liquid that coats the stomach. This contrast material helps any abnormalities show up more clearly on an X-ray.
References
- Olive AP, et al. Infantile hypertrophic pyloric stenosis. http://www.uptodate.com/home/index.html. Accessed June 23, 2010.
- Sondheimer JM, et al. Gastrointestinal tract. In: Hay WW Jr., et al. Current Diagnosis & Treatment: Pediatrics. 19th ed. New York, N.Y.: McGraw-Hill; 2007. http://www.accessmedicine.com/content.aspx?aID=3403837. Accessed June 23, 2010.
- D'Agostino J. Common abdominal emergencies in children. Emergency Medicine Clinics of North America. 2002;20:139.
- Guidelines for surgical treatment of infantile hypertrophic pyloric stenosis. Los Angeles, Ca.: International Pediatric Endosurgery Group. http://www.ipeg.org/education/guidelines/pyloric.html. Accessed July 7, 2010.
- Pyloric stenosis. The American Pediatric Surgical Association. http://www.eapsa.org//Surgeons/Content/NavigationMenu/Media/Resources/Pyloric_Stenosis.htm. Accessed July 7, 2010.
- Hoecker J (expert opinion). Mayo Clinic, Rochester, Minn. July 8, 2010.

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