Correct answer to Q1 is: Liver and pylorus

Correct answer to Q2 is: Pyloric muscle hypertrophy and pathologic elongation of the pylorus

Correct answer to Q3 is: Surgically with a longitudinal pyelomyotomy

The girl was treated with a pyelomyotomy and supplemental oral antacida. In the following months she was still vomiting, but only a few times a day and no longer explosively.

Discussion

Infantile hypertrophic pyloric stenosis (IHPS) is a common condition in neonates involving narrowing of the pylorus. In Western countries its prevalence is 2 in 1,000 live births (1). The hypertrophy of the pyloric muscle leads to decreased gastric outlet and thus projectile postprandial vomiting. Symptoms often show when the infant is 3-6 weeks old. IHPS can occur as an isolated phenomenon or can be linked with congenital malformations or genetic syndromes (2). Ultrasound is the modality of choice with a sensitivity of 97% and specificity of 100% (3).

Diagnosis is based on a) pyloric muscle thickness/diameter >3 mm on a transverse image (normally <2 mm), b) pyloric length/longitudinal measurement >15-17 mm, and/or c) pyloric transverse diameter >13 mm, with pyloric muscle thickness being the most sensitive finding (4).

IHPS is treated surgically with pyloromyotomy, where the pyloric muscle is incised longitudinally down to the submucosa.

Correct answer to Q4 is: Exaggerated ventricle peristalsis with no opening of the pylorus.

Additional Discussion:

Conclusion

Infantile hypertrophic pyloric stenosis is a common condition among newborns with symptoms of postprandial projectile vomiting typically arising around 3-6 weeks of age. Ultrasound is the diagnostic modality of choice due to its high sensitivity and specificity. Pyelomyotomy is the curative treatment of the condition.

Conflicts of interest

“The authors declare no conflict of interest.”

References

1. MacMahon, B. The continuing enigma of pyloric stenosis in infancy, a review. Epidemiology. 2006;17(2):195-201.
2. Peeters B. et al. Nat. Rev. Gastroenterol. Hepatol. 2012;9, 646–660.
3. Godbole P, Sprigg A, Dickson J, Lin P. Ultrasound Compared with Clinical Examination in Infantile Hypertrophic Pyloric Stenosis. Arch Dis Child. 1996;75(4):335-7.
4. Blumhagen J D, Maclin L, Krauter D, Rosenbaum DM, Weinberger E. AJR. Sonographic diagnosis of hypertrophic pyloric stenosis. 1988;150(6), 1367-1370