Pyloric stenosis in babies: Leading cause of forceful vomiting in newborns

Pyloric stenosis is a problem that affects babies between birth and six months of age, and causes forceful vomiting that can lead to dehydration. It is the second most common problem requiring surgery in newborns.

The lower portion of the stomach that connects to the small intestine is known as the pylorus. In pyloric stenosis, the muscles in this part of the stomach enlarge, narrowing the opening of the pylorus and eventually preventing food from moving from the stomach to the intestines.

Because the stomach opening becomes blocked and babies start vomiting, several problems can happen. The most serious problem is dehydration. When a baby vomits regularly, he or she will not get enough fluids to meet his or her nutritional needs. Babies have smaller bodies than adults and cannot tolerate losing fluid as easily as adults can. Minerals that the body needs to stay healthy, such as potassium and sodium, are also lost as the baby vomits. Babies who lack the right amount of water and minerals in their bodies can become very sick quickly which can be life-threatening.

Pyloric stenosis in babies usually presents between two and eight weeks of life and rarely beyond three months. The most common symptoms noted in a baby with pyloric stenosis is forceful, projectile vomiting. Large amounts of breast milk or formula are vomited, and may go several feet across a room (projectile). The baby is usually quite hungry and eats or nurses eagerly after vomiting. The vomited milk is sometimes curdled in appearance, because as the milk remains in the stomach and does not move forward to the small intestine, the stomach acid “curdles” it. Weight loss occurs as the disease progresses (baby fails to thrive), urinary frequency and volume reduce such that parents note they are changing fewer, and less heavy, nappies. Stool frequency is also reduced. It is important to know that the symptoms of pyloric stenosis may resemble other conditions or medical problems, hence, require proper medical consultation to determine the specific cause of the baby’s symptoms.

There is no specific known cause of this condition, but some factors are known to increase its likelihood. There is a 4:1 male preponderance, and chances increase if there is history in other relatives (can be genetic). The recurrence risk of this condition in the child of an affected father is five per cent for male child and two per cent for a female offspring. The risk of developing this condition in children of an affected mother is much higher at 17 per cent. Pyloric stenosis in babies is also seen to be less frequent in breast-fed babies, and more seen in babies of Caucasian ancestry.

The doctor can diagnose pyloric stenosis of the baby on the basis of a good history and clinical examination. An ultrasound of the abdomen can be performed if there is doubt about the diagnosis (this will show the thickening of the pylorus). Blood tests may be done to determine any complications resulting from longstanding vomiting due to the condition.

Once the diagnosis of pyloric stenosis in a baby has been made, management plan usually involves initial stabilisation of the baby to correct any complications developed due to the condition and then surgery is required to relieve the condition. It is a relatively short procedure done when the baby has been put to sleep (general anesthesia) and a small incision made above the umbilicus to easily locate and relieve the pylorus of its tightening to allow easy flow of feeds from the stomach to the intestines.

 Dr Ian Shyaka , Resident in Surgery,

Rwanda Military Hospital,