Alkali Denaturation Test (APT and Downey)
Test Summary
The Alkali Denaturation Test (APT) is useful in distinguishing between newborn swallowing mother's blood and fetal gastrointestinal bleeding (Melena neonatorum).
The APT test is used to determine whether blood in the diaper, vomitus, or feces of a neonate contains predominantly the baby's or the mother's blood. It is a crude, qualitative method based on resistance of hemoglobin F to alkali denaturation.
Aliases
- N/A
Specimen Collection
Special Instructions
N/A
Preferred Specimen
2 mL of a random, bloody stool submitted in a plastic leak-proof container
Minimum Volume
1 mL
Instructions
Note: The specimen requirement for this test is a grossly bloody (red) non-tarry stool (or bloody vomitus, bloody mucus or blood-stained diaper from newborn within 1 day of birth). If the specimen submitted was not bloody and we were unable to elute any red color from it, the test cannot be performed and will be cancelled
Patient Preparation
N/A
Storage
N/A
Transport Temperature
Room temperature
Specimen Stability
- Room temperature: 7 days
- Refrigerated: 7 days
- Frozen: Unacceptable
Limitations
N/A
Other Acceptable Specimens
2 mL bloody vomitus or bloody mucus, submitted in a plastic leak-proof container or bloody diaper submitted in a plastic leak-proof container
Unacceptable Specimens
Received frozen
Order Code
APT
EPIC (Premier) Code
LAB1993
Includes
N/A
CPT Code
- 85460
Billing Code
- 700000
CPT Statement
Methodology
Colorimetric (C)
FDA Status
FDA Approved
Physician Attestation of Informed Consent
N/A
Testing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly VA, 20153
14225 Newbrook Drive
Chantilly VA, 20153
Reference Range
Negative for fetal blood
Setup Schedule / Expected Turnaround Time
Daily; Report available: 1 day
Specimen Collection
Special Instructions
N/A
Preferred Specimen
2 mL of a random, bloody stool submitted in a plastic leak-proof container
Minimum Volume
1 mL
Instructions
Note: The specimen requirement for this test is a grossly bloody (red) non-tarry stool (or bloody vomitus, bloody mucus or blood-stained diaper from newborn within 1 day of birth). If the specimen submitted was not bloody and we were unable to elute any red color from it, the test cannot be performed and will be cancelled
Patient Preparation
N/A
Storage
N/A
Transport Temperature
Room temperature
Specimen Stability
- Room temperature: 7 days
- Refrigerated: 7 days
- Frozen: Unacceptable
Limitations
N/A
Other Acceptable Specimens
2 mL bloody vomitus or bloody mucus, submitted in a plastic leak-proof container or bloody diaper submitted in a plastic leak-proof container
Unacceptable Specimens
Received frozen
Result Information
Methodology
Colorimetric (C)
Testing Laboratory
N/A
Reference Range
Negative for fetal blood
Setup Schedule / Expected Turnaround Time
Daily; Report available: 1 day