Hypertrophic Pyloric Stenosis

Hypertrophic Pyloric Stenosis is a condition that affects the digestive system in infants, specifically the muscle at the lower end of the stomach called the pylorus. In this condition, the muscle becomes abnormally thickened, which blocks food from passing into the small intestine. This blockage causes frequent, forceful vomiting, which can lead to dehydration and weight loss. Babies with this condition often appear hungry after vomiting and may have a visible wave of stomach contractions. It usually develops within the first few weeks of life and requires medical evaluation to confirm the diagnosis.

Hypertrophic Pyloric Stenosis (HPS) is characterized by hypertrophy and hyperplasia of the pyloric muscle, leading to gastric outlet obstruction in infants. The exact cause is unknown but is thought to involve a combination of genetic and environmental factors. The thickened pyloric muscle narrows the pyloric canal, preventing normal gastric emptying. Clinically, it presents with projectile nonbilious vomiting, palpable olive-shaped mass in the right upper quadrant, and signs of dehydration and hypochloremic metabolic alkalosis. It is the most common cause of gastric outlet obstruction in infants and typically manifests between 2 to 8 weeks of age. Early recognition is critical to prevent complications such as electrolyte imbalances and failure to thrive.