The most confirmatory investigation is endoscopy of upper gastrointestinal tract. Laboratory often find hypochloremic, hypokalemic, and alkalotic due to loss of hydrogen chloride and potassium. High urea and creatinine levels may also be observed if the patient is dehydrated. Abdominal X-ray may show a<unk>  fluid level which would support the diagnosis. Barium meal and follow through may show an enlarged stomach and pyloroduodenal stenosis. Gastroscopy may help with cause and can be used therapeutically. Differential diagnosis The differential diagnosis of<unk>  may include: early<unk>  carcinoma, hiatal hernia, gastroesophageal reflux, adrenal insufficiency, and inborn errors of metabolism.
Gastric outlet obstruction
Esophageal food bolus obstruction
Esophagogastric dissociation
Esophagogastric junction outflow obstruction
Gastric volvulus
Inspissation
Exocrine pancreatic insufficiency
Sphincter of Oddi dysfunction