Test Code LAB4090 APT (DOWNEY TEST)
Specimen Type
Varies, see Collection Instructions
Collection Instructions
Amniotic Fluid: Collection into an EDTA vacutainer is preferred to prevent clotting of grossly bloody specimen.
Vaginal Fluids: Specimen suspected of containg fetal blood. Collection into an EDTA vacutainer is preferred to prevent clotting of grossly bloody specimen.
Emesis: Submit emesis from newborn suspected of containing fetal blood in leakproof plastic container.
Stool: Submit a stool sample from a newborn suspected of containing fetal blood.
Turnaround Time
STAT: 1 hour
Routine: 4 hours
Test Schedule
Daily
Specimen Processing
48 hours Room Temp
72 hours Refrigerated
Method
Visual Hemolysis
Reference Ranges
APT: Fetal Hemoglobin Present or Absent APT
Reporting Limit
The presence of adult red cells, mixed with fetal may mask the end result.
Synonyms
Downey Test; Fetal Hgb (Qual)
Test Components
APT
CPT Codes
83033
Rejection Criteria
Tarry stools because the proteins have been denatured and will not react.