Infant with vomiting in a patient with ductal-dependent congenital heart disease

Upper GI and US of Prostaglandin E induced gastritis
AP image from an upper GI exam (above) shows persistent narrowing of the pyloric channel. Transverse US of the pylorus (below) shows marked thickening of the central hyperechoic pyloric mucosa and a normal thin appearance of the peripheral hypoechoic pyloric muscle which measures 1.2 mm thick.

The diagnosis was prostaglandin E induced gastritis.