PYLORIC STENOSIS

RMacLean
January 2005

The stomach has two valves, one at the top (lower esophageal sphincter-associated with reflux) where food enters and one at the bottom where food leaves to enter the small intestine.  It is the valve at the bottom of the stomach or pylorus that is affected in pyloric stenosis.  A condition that can sometimes be initially confused with reflux, pyloric stenosis occurs when the muscle around the pylorus has grown too large.  Most babies with pyloric stenosis will begin to vomit during the second to third week of life, making it easy to confuse with reflux in the beginning.  They begin with "spitting up" that turns into forceful projectile vomiting after feeding.

The pyloric valve continues to enlarge over time and eventually blocks the stomach from emptying. This increases the vomiting and the baby begins to lose weight, may become dehydrated and start to become less active.

A physical exam by the doctor can sometimes show an enlarged pyloric valve and an upper GI may be performed to determine if the baby has pyloric stenosis.  They may also do an abdominal ultrasound.

If the baby does have pyloric stenosis the doctor will check for dehydration through blood work, an IV will be inserted to replace fluids and the baby will likely go to surgery the next day.

The child will have a pyloromyotomy (pie-lore-oh-my-ot-toe-me) performed.  This operation involves making a small incision around the belly button or on the right side of the stomach and opening the muscle around the pyloric valve of the stomach.  Most babies will be discharged one or two days after surgery and will not have any long term complications.

Reviewed By Dave Olson, MD
Fellow, American Academy of Pediatrics
Graduate University of Michigan School of Medicine