Test : APT test/Swallowed Blood syndrome Test/ Fetal hemoglobin
Indications : This test is done to diagnose swallowed blood syndrome and differentiate this condition from gastrointestinal hemorrhage in the new born.
Physiology : This test uses alkali denaturation of fetal hemoglobin to determine if blood is present in the stool of a newborn as a result of swallowing maternal blood or is due to perinatal or neonatal Gastro-intestinal hemorrhage. In swallowed blood syndrome, blood or bloody stools are passed usually on the second or third day of life. The blood may be swallowed during delivery or may be from a fissure of the mother’s nipple. The test is based on the fact that the infant’s blood contains > 60% fetal hemoglobin that is alkali resistant. Swallowed blood of maternal origin contains adult hemoglobin, which is converted to brownish alkaline hematin on the addition of alkali.
Normal Range : Report will provide indication if blood is of maternal or infant origin (adult or fetal hemoglobin).
Careers
Method..
The blood is mixed with a small amount of tap water to cause hemolysis. The sample is next centrifuged for several minutes. The pink hemoglobin-containing supernatant is then mixed with 1 mL of 1% NaOH for each 5 mL of supernatant. The color of the fluid is assessed after 2 minutes. Fetal hemoglobin will stay pink and adult hemoglobin will turn yellow-brown since adult hemoglobin will convert to hematin which has a hydroxide ligand.
thank for the information on this web, as i was reading on Apt`s test,I was expecting that you were going to explain more especially in terms of the results after that test has been done, but you didn`t say anything!! how would i know if the blood is the fetal or maternal???