A Vomiting Three Week Old

What's Your Diagnosis?

Doctor listening to a baby breathing
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You're a little worried about your newborn baby. He was born full-term and had been breastfeeding and gaining weight well. He was exposed to an uncle with pertussis (whooping cough) and so had been placed on the antibiotic erythromycin as a preventative measure, but had otherwise seemed fine.

Your Baby is Spitting Up

For the past few days, he has been spitting up after his feedings. Although this is your first baby, you had worked in a daycare and so had seen a lot of kids spitting up. Your baby's spitting up seems a little more forceful, almost going across the room, and that is why you are worried.

You go to see your pediatrician, who isn't too worried because he isn't vomiting after every feeding and he hasn't lost any weight. He suggests stopping breastfeeding and giving him an elemental formula, like Nutramigen or Alimentum, instead. He also thinks that your baby may have an upset stomach because of the erythromycin he had been taking, and so also prescribes Zantac.

You are reassured that he hasn't lost weight, but decide that stopping breastfeeding is a bad idea and so you continue.

More Vomiting

Over the next few days, the vomiting increases, occurring right after or within 30 minutes of a feeding. The Zantac does not seem to be working and you are also concerned because he does not seem to be having as many wet diapers as he used to and he is sleeping more.

In your pediatrician's office, they note that he has lost 1/2 pound, but they don't share your concern. Since he drinks a few ounces of Pedialyte in the office, the pediatrician feels that the problem is a milk intolerance and that you should stop breastfeeding. He explains that the weight loss is probably because he was weighed on a different scale and that you aren't noticing wet diapers because today's diapers are so super-absorbent.

You are far from reassured now and your pediatricians 'advice' doesn't make sense to you. After all, you are using the same diapers you had been using all along and if they were so super-absorbent, how come they felt soaking wet before?

You are even more concerned because your husband had something similar happen to him as a baby and he needed emergency surgery to fix it.

Because your baby has had projectile vomiting for several days that has been worsening, you decide to go to the emergency room at your local Children's Hospital.

Why Is This Baby Dehydrated?

Upon your arrival, because of his decreased urine output, dry mouth, and sunken fontanelle, they feel that he is dehydrated and he is seen right away.

They decide to not let him eat anymore (NPO) and start intravenous fluids while they try to figure out what is wrong.

They ask you several more questions, including:

  • Is he just spitting up non-forcefully or is it real, forceful, projectile vomiting?
  • When he vomits, does it just look like breastmilk or is it dark green (bilious emesis)?
  • Has he been vomiting since birth, or is this a new thing?
  • Is he having bloody diarrhea?
  • Has anyone else at home had vomiting or diarrhea?
  • Do you feel like you have a good supply of breastmilk and is he latching on and sucking well?

You answer that no, no one else has been sick, he doesn't have diarrhea or dark green vomiting, and that he does have projectile vomiting. You state that you also feel like he has been breastfeeding well and that you have a good supply of breastmilk.

The doctors say something about not feeling an "olive," but that they are pretty sure that they know what is wrong. They order a test to confirm the diagnosis.

After your baby with projectile vomiting was evaluated in the emergency room, the doctors decide to do a test to confirm what they think is wrong. They had considered doing an upper GI test but decided that an ultrasound would be a better choice.

It's Pyloric Stenosis

The ultrasound is done and shows that your baby's pyloric muscle has a thickness of greater than 4mm and a pyloric length greater than 16mm, which means that he has hypertrophic pyloric stenosis, a common cause of projectile vomiting at this age.

You learn that pyloric stenosis is the most common cause of gastroesophageal obstruction in newborns, occurring in about 1 in 250 to 500 infants. Although it is often diagnosed at about 3 weeks of age, it can occur anywhere from 1 week to 5 months. In this condition, the pylorus, or muscular outlet of the stomach becomes enlarged, so that breastmilk or formula can't empty out of the stomach and is vomited up instead.

Although many infants with pyloric stenosis have electrolyte problems, your child's blood work is normal, he is easily rehydrated, and he is scheduled for surgery to repair the pyloric stenosis.

After meeting with the Pediatric Surgeon, you learn that he will need a pyloromyotomy, in which the pyloric muscle is cut or spread open to enlarge it.

Your baby's surgery goes well and he is back to breastfeeding well and is home for a few days.

Although the cause of pyloric stenosis isn't known, you find out that your baby had many risk factors, including being a firstborn male (pyloric stenosis is more common in boys than girls), having a possible family history since dad may have had it too, and having taken erythromycin, which has recently been associated with pyloric stenosis.

Although the case described here was very 'classic' for pyloric stenosis, the diagnosis is not always so easy to make.

More often, instead of projectile vomiting after each and every feeding and weight loss, these babies can present with just occasional projectile vomiting, once or twice a day. It is in these more difficult cases that the diagnosis may be delayed.

Projectile Vomiting

Among the conditions often confused with pyloric stenosis are:

  • Gastroesophageal reflux - infants with reflux will often have nonforceful, non-projectile vomiting. They may also be fussy and have poor weight gain if they develop GERD.
  • Milk/formula intolerance - although they will often have gas and diarrhea, infants with a formula intolerance can sometimes have spitting up or vomiting.
  • Gastroenteritis - can cause vomiting, but you would also expect diarrhea and other contacts who are sick with similar symptoms
  • Intestinal malrotation with obstruction or volvulus - in this condition, an infant's intestines can twist and become obstructed, causing pain, a distended abdomen, and bilious (dark green) vomiting. Unlike reflux or even mild cases of pyloric stenosis, a volvulus is a medical emergency.

This case also highlighted some 'mistakes' that pediatricians sometimes make, including not recognizing dehydration because of the belief that diapers are super-absorbent, advising that an infant would be better off not breastfeeding, and not recognizing the importance of weight loss, which is never normal in younger children.

If your baby has persistent projectile vomiting that is not responding to your pediatrician's recommendations, including medications like Zantac or formula changes, you might ask if an upper GI or a pyloric ultrasound might be required to help make a diagnosis, especially if your baby is losing weight or just not gaining weight well.