<prompt> Failure to pass meconium within 48 hrs of birth in a newborn with no obvious external abnormality should lead to the suspicion ofAnal atresiaCongenital pouch colonCongenital aganglinosisMeconium ileus  <response>: Read what Nelson says about Hirschsprungs disease Congenital aganglionosis.Ninety-nine per cent of full-term infants pass meconium within 48hrs of birth. Hirschsprung disease should be suspected in any fill term infant with delayed passage of stool. 