A three month old child was presented as an emergency case at the children's department.
For a longer period this child vomits after each meal. Clinical not dehydrated.
CAVE: ( Infantile) Hypertrophic Pyloric Stenosis or ( I) HPS.
Examination in right sided position.
The correct measurement for HPS may vary from article to article.
It is helpful to remenber the first digits of the number pi 3,1415.
- single muscle layer > 3mm
- pyloric transverse diameter > 14 mm
- longitudinal measurement > 15 mm
In this case there was an incorrect measurement what led to a misinterpretation for HPS.
Secondly there was no clear antral nipple sign, this refers to pyloric mucosa protruding into the gastric antrum.
Several minutes later a second look revealed passage of gastric content through the pylorus, distending the antropyloric region.
Now a correct measurement of the single muscle layer amounted to 1,3 mm and a normal longitudinal measurement of 11 mm
Dynamic evaluation is crucial, as a normal passage of gastric content which distends the antropyloric region excludes HPS.