All are false except one in case of hyperophic pyloric stenosis -

Ans is 'd' ie USG is diagnostic test Hyperophic Pyloric Stenosis (HPS) The musculature of the pylorus and adjacent antrum is grossly hyperophied, the hyperophy being maximum in the pylorus itself. It occurs in approximately 3 in 1000 live bih and is the most common surgical cause of vomitting in infancy. M > F (4 : 1)* Characterstically the first born male child is affected. The conditon is most commonly seen at 4 wks after bih ranging from the 3rd wk to on rare occasion, the 7th. However, 20% of infants are symptomatic from bih, and most are symptomatic within the first 2 months after bih. Non-bilious vomiting, becoming increasingly projectile, occurs over several days to weeks. Eventually the infant will develop a nearly complete obstruction by the second to fouh week of life and will not be able to hold down even clear liquids. This invariably proceeds to severe dehydration if not t/t. These infants develop a metabolic alkalosis with severe depletion of potassium and chloride ions. " The diagnosis of pyloric stenosis usually can be made on physical examination by palpation of the typical 'olive' in the right upper quadrant and the presence of visible gastric waves on the abdomen. When the olive cannot be palpated, ultrasound in experienced hands will diagnose the condition accurately in 95 percent of pts." - Schwaz. Treatment - Pyloric stenosis is never a surgical emergency although dehydration and electrolyte abnormalities may present a medical emergency Fluid resuscitation and correction of electrolyte abnormalities and metabolic alkalosis is essential before surgery. - Surgery : Fredet-Ramstedt pyloromyotomy. (In it the pyloric mass is split without cutting the mucosa) Also know Administration of erythromycin in early infancy has been linked to the subsequent development of HPS. Jaundice may be seen in HPS, although cause is not clear.