Characteristic feature of pyloric stenosis?

Concept:-

• Vomiting, also known as emesis and throwing up, is the involuntary, forceful expulsion of stomach contents through the mouth and the nose.
• Projectile vomiting is an acute form of vomiting, sometimes seen in infants, which may include vomiting from the nose.
• Pyloric stenosis is defined as the narrowing of the outlet of the stomach so that food cannot pass easily from it into the duodenum, resulting in feeding problems and projectile vomiting.

Signs and symptoms:

• Vomiting after feeding. The baby may vomit forcefully, ejecting breast milk or formula up to several feet away (projectile vomiting).
• Persistent hunger. Stomach contractions.
• Dehydration.
• Changes in bowel movements.
• Weight problems.

Causes:

• Sex: pyloric stenosis is seen more often in boys — especially firstborn children — than in girls.
• Premature birth. 
• Family history. 
• Smoking during pregnancy. 
• Early antibiotic use. 
• Bottle-feeding.