 Alkali denaturation test

The alkali denaturation test, also known as A or Apt test, is a medical test used to differentiate fetal or neonatal blood from maternal blood found in a newborn's stool or vomit, or from maternal vaginal blood.The test was developed by Leonard Apt (1922–2013), an American pediatric ophthalmologist.The test was originally used to identify the source of bloody stools in newborn infants.