<prompt> True about hyperophic pyloric stenosis is all except:Typical electrolyte abnormality is Hypochloremic, hypokalemic, metabolic alkalosis with paradoxical aciduria .First born male is commonly affectedRamstedt operation is doneVisible peristalsis is always seen  <response>: Clinical presentation: Infants is normal at bih, symptomatic between the ages of 3-6 weeksQ . Infants with HPS typically present with projectile non bilious vomitingQ. Visible gastric peristalsis may be seen not alwaysas a wave of contraction from the left upper quadrant to the epigastriumQ. Typical electrolyte abnormality: Hypochloremic, hypokalemic, metabolic alkalosis with paradoxical aciduriaQ. First born male commonly affected. Ramsted operation commonly done. 