SymptomChildren's health
Olive-Shaped Abdominal Mass (Pyloric Olive)
An olive-shaped abdominal mass, or "pyloric olive", is a firm, movable lump about the size and shape of an olive felt in the upper middle or right upper abdomen of a young baby. It is the thickened muscle of the pylorus, the outlet of the stomach, and it is the classic sign of pyloric stenosis. It usually appears with forceful projectile vomiting after feeds at 2 to 8 weeks of age. Pyloric stenosis is fully curable with a short operation.
Also called: Pyloric olive, olive mass, palpable olive, pyloric tumor (old term)
At a glance
- What it is
- A firm, olive-sized lump in a baby's upper abdomen, formed by thickened pyloric muscle.
- What it means
- Almost always pyloric stenosis, a blockage at the stomach outlet.
- Typical age
- 2 to 8 weeks, most often 3 to 6 weeks. More common in first-born boys.
- Other signs
- Projectile vomiting after feeds, hunger right after vomiting, dehydration, poor weight gain.
- Diagnosis
- Abdominal ultrasound measuring the thickness and length of the pylorus.
- Treatment
- Fluids to correct dehydration, then pyloromyotomy surgery.
When to get help
Call 911 or go to the ER
- A baby who is floppy, very sleepy, hard to wake, or has a sunken soft spot and no wet diapers for 8 hours or more
- Green (bile-stained) vomit in a baby at any age, which suggests a different, more urgent blockage
- Vomiting with a swollen, hard or tender belly, or blood in the vomit or stool
See a doctor within a day or two
- Forceful, projectile vomiting after most feeds in a baby aged 2 to 12 weeks
- A baby who vomits and then wants to feed again straight away, and is losing weight
- A lump felt in a baby's upper belly
- Fewer wet diapers than usual with ongoing vomiting
Book a routine appointment
- Small, effortless spit-ups in a baby who is gaining weight and content, which is normal reflux (mention at the next checkup)
What the "olive" is
The pylorus is a ring of muscle at the lower end of the stomach that controls the flow of milk into the small intestine. In pyloric stenosis, this muscle thickens and lengthens over the first weeks of life until it narrows the channel and blocks feeds from leaving the stomach. The thickened muscle forms a firm, oval mass about 1.5 to 2 cm long, which doctors liken to an olive in size, shape and feel.
The olive sits just above and to the right of the belly button, under the edge of the liver. It is easiest to feel when the baby is calm, relaxed and has just vomited or had the stomach emptied, because a full stomach hides it.
Symptoms that come with an olive mass
- Projectile vomiting: forceful vomiting that can shoot 1 to 3 feet (30 to 90 cm), usually within 30 to 60 minutes of a feed. It gets more frequent over days.
- Non-bilious vomit: milk or curdled milk, not green, because the blockage is above the bile duct.
- Hunger after vomiting: the baby is eager to feed again right away (persistent hunger).
- Visible stomach waves: ripples moving from left to right across the upper belly after a feed, as the stomach tries to push milk through. See visible peristalsis.
- Poor weight gain or weight loss.
- Dehydration: fewer wet diapers, dry mouth, sunken soft spot, lethargy.
- Fewer, smaller stools.
- Jaundice: mild yellowing in a minority of babies.
Who gets pyloric stenosis
It affects about 2 to 3 babies in every 1,000. Risk factors include:
- male sex (boys are affected about 4 times more often than girls)
- being first-born
- a parent or sibling who had it
- exposure to certain antibiotics, especially erythromycin or azithromycin, in the first 2 weeks of life
How the olive mass is diagnosed
A doctor gently feels the upper abdomen, often while the baby sucks on a bottle of sugar water to relax the tummy muscles. An experienced examiner feels the olive in many babies, but it is often missed early, so imaging is used.
- Ultrasound is the test of choice. Pyloric stenosis is confirmed when the pyloric muscle wall is 3 mm or thicker and the channel is about 15 to 17 mm or longer, with milk failing to pass.
- Blood tests check for dehydration and the typical salt imbalance caused by vomiting stomach acid: low chloride, low potassium and high bicarbonate (hypochloremic metabolic alkalosis).
- An upper GI contrast study is used only if ultrasound is unclear, and can rule out malrotation when vomit is green.
Other causes of a mass or vomiting in babies
| Condition | How it differs |
|---|---|
| Normal reflux | Small, effortless spit-ups, good weight gain, no mass |
| Intussusception | Older babies (6 to 36 months), episodes of severe crying, sausage-shaped mass, red jelly stools |
| Malrotation with volvulus | Sudden green vomiting at any age, surgical emergency |
| Overfeeding or milk protein allergy | No mass, vomiting less forceful |
| Kidney or adrenal masses | Felt in the flank, not the upper middle abdomen |
Treatment
- Rehydration first. IV fluids correct dehydration and the salt imbalance, usually over 12 to 48 hours. Surgery is not rushed until blood levels are safe for anesthesia.
- Pyloromyotomy. The surgeon cuts through the thickened muscle lengthwise down to the lining, which lets the channel open. It is often done through tiny keyhole (laparoscopic) incisions or a small cut near the belly button.
- Feeding again. Feeds usually restart within a few hours after surgery and build up over a day. Some vomiting in the first 24 to 48 hours is common.
Most babies go home within 1 to 2 days and grow normally afterward. The muscle does not thicken again, and long-term problems are very rare.
Frequently asked questions
What does an olive-shaped mass in a baby mean?
A firm, movable, olive-sized lump in the upper middle or right upper belly of a young baby almost always means pyloric stenosis, a thickening of the stomach outlet muscle. It usually comes with projectile vomiting and needs prompt medical assessment.
Can you see or feel the pyloric olive at home?
Parents rarely feel it, because it lies deep under the liver edge and is easiest to find when the stomach is empty and the baby is relaxed. Watch instead for projectile vomiting, hunger after vomiting, and fewer wet diapers, and see a doctor.
Is pyloric stenosis serious?
It can lead to serious dehydration and salt imbalances if not treated, but it is not life-threatening when diagnosed promptly. The operation to fix it is short, very effective, and most babies recover fully within days.
Can pyloric stenosis go away without surgery?
Rarely. Surgery is the standard treatment because it is quick and highly effective. In some countries, medicines (atropine) are used when surgery is not possible, but they take longer and work less reliably.
Sources
This guide was written from current patient and clinical guidance, including:
- American Academy of Pediatrics (HealthyChildren.org): Pyloric Stenosis
- MedlinePlus: Pyloric stenosis
- NHS: Pyloric stenosis
- American Pediatric Surgical Association: Pyloric stenosis
- American College of Radiology: ACR Appropriateness Criteria, Vomiting in Infants