Introduction

• Congenital or acquired hypertrophy of circular muscle fibers or hyperplasia of pyloric mucosa (or both) of pyloric ring of stomach.
• Cause: may be associated with excess gastrin levels or abnormal neuro-muscular control.
• Signs: vomiting food at variable interval following feeding.
• Diagnosis: no definitive test - suspect on clinical and contrast radiographic examination + gastroscopy.
• Treatment: pyloroplasty or pyloromyotomy.
• Prognosis: good.

Pathogenesis

Etiology

• Excessive gastrin levels causing hypertrophy of circular muscle fibers (congenital form).
• Possible neuro-muscular dysfunction.
• Acquired = mucosal hypertrophy.

Pathophysiology

• Neuromuscular dysfunction → motility disorder → failure of pylorus to open.
• Obstruction to gastric outflow → gastric distension → gastrin release → hypertrophy of muscle fibers and mucosal hyperplasia.
• Failure of pyloric ring to relax → vomiting of stomach contents.

Timecourse

• Weeks to months.

Diagnosis

Treatment

Outcomes