A pediatrician friend of mine consulted about a one-month-old baby boy. The baby was fine in the initial weeks, but in recent days, he has been vomiting in a projectile manner after every feeding. After vomiting, he tries to nurse because his hunger continues, but he loses weight as he cannot feed adequately. When his urine output and bowel movements decreased and he started to become lethargic, they came to see us. Physical examination, blood tests, and abdominal ultrasound revealed excessive enlargement of the muscle at the stomach outlet, causing an obstruction there. After performing the necessary surgery, we discharged the baby in his mother’s arms.
In the Pediatric Surgeon’s Log, I provided brief, concise information about “Pyloric Stenosis.” Enjoy your reading.
The full name of this condition is “Infantile Hypertrophic Pyloric Stenosis.” “Infant” refers to babies under 1 year old. “Hypertrophic” means enlarged. The last part of the stomach is called the pylorus, and “stenosis” means narrowing. So, it refers to a narrowing at the stomach outlet in young babies. Sometimes the term “idiopathic” is used instead of “infantile,” meaning “of unknown cause.” Previously, the term “congenital,” meaning present at birth, was used. However, it became clear that these babies are normal at birth, and their symptoms start appearing after three weeks. Therefore, “idiopathic” started being used instead of “congenital.” This has a strategic importance, as many private health insurances unfortunately do not cover congenital conditions. Although these insurers do not want to cover the issue for babies, I emphasize that this condition is not congenital.
It typically appears between 3-5 weeks of age and is very rare after 12 weeks. It occurs in about 1-3 out of every 1000 babies and is five times more common in boys. It is especially more prevalent in first-borns, premature babies, and babies of young mothers.
The exact cause is unknown, but certain antibiotics, smoking, bottle feeding, and most importantly, genetic factors are thought to contribute. For instance, the likelihood of a sibling also having this condition is 30 times higher than in the general population.
Clinical findings are exactly like the baby I just described. After feeding, they vomit the food accumulated in their stomach in a projectile manner through their mouth and nose. Since they vomit stomach contents, the vomit usually does not contain green bile. They start losing weight and have decreased bowel movements and urination. I won’t discuss the very atypical findings, but we know that these babies may also develop mild jaundice. The vomiting I mentioned is different from the reflux vomiting commonly seen in babies, which does not occur in a projectile manner and appears as dribbling from the mouth about 10 minutes after feeding.
To confirm a diagnosis of pyloric stenosis in babies we suspect from their history, we measure the thickness and length of the muscle at the stomach outlet using ultrasound, and assess the losses in stomach contents through blood tests. If the babies are fit for surgery, we perform an operation to cut the muscle and widen the stomach outlet.
This surgery has a very high success rate. Although the muscle still appears thick on ultrasound for up to a year, the clinical condition improves immediately. 
To answer a frequently asked question, in the long-term follow-up, babies who have undergone this surgery show no difference from other babies; their digestive system symptoms and stomach emptying are the same as normal individuals.
With that, we conclude this log entry. Stay happy.
Prof. Dr. Egemen Eroğlu
June 2024