Test Code CAH2T Congenital Adrenal Hyperplasia Newborn Screen, Blood Spot
Reporting Name
CAH Newborn Screen, BSPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Second-tier testing of newborns with abnormal screening result for congenital adrenal hyperplasia
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Portions of this test are covered by patents held by Quest Diagnostics
Necessary Information
Birth weight, time of birth, and gestational age are required.
Specimen Required
Supplies: Card-Blood Spot Collection (Filter Paper) (T493)
Container/Tube:
Preferred: Blood Spot Collection Card
Acceptable: Local newborn screening card, Whatman 903 filter paper, PerkinElmer 226 filter paper, Munktell filter paper
Specimen Volume: 2 Blood spots
Collection Instructions:
1. Do not use device or capillary tube containing EDTA to collect specimen.
2. Completely fill at least 2 circles on the filter paper card (approximately 100 microliters blood per circle).
3. Let blood dry on filter paper at ambient temperature in a horizontal position for a minimum of 3 hours.
4. Do not expose specimen to heat or direct sunlight.
5. Do not stack wet specimens.
6. Keep specimen dry.
Additional Information:
1. For collection instructions, see Blood Spot Collection Instructions
2. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777)
3. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800)
Specimen Type
Whole bloodSpecimen Minimum Volume
1 Blood spot
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole blood | Ambient (preferred) | 90 days | FILTER PAPER |
Frozen | 90 days | FILTER PAPER | |
Refrigerated | 90 days | FILTER PAPER |
Reject Due To
Blood spot specimen that shows serum rings or has multiple layers | Reject |
Insufficient specimen | Reject |
Unapproved filter papers | Reject |
Reference Values
17-HYDROXYPROGESTERONE (17-OHP)
<15.1 ng/mL
ANDROSTENEDIONE
<3.1 ng/mL
CORTISOL
Not applicable
11-DEOXYCORTISOL
<15.1 ng/mL
21-DEOXYCORTISOL
<4.1 ng/mL
(17-OHP + ANDROSTENEDIONE)/CORTISOL RATIO
<1.1
Note: Abnormal (17-OHP + Androstenedione)/Cortisol Ratio: ≥1.1 is only applicable when 17-OHP is elevated
11-DEOXYCORTISOL/CORTISOL RATIO
Not applicable
Interpretation
Findings of a 17-hydroxyprogesterone (17-OHP) value greater than 15.0 ng/mL and a high (17-OHP + androstenedione)/cortisol ratio (≥1) are supportive of the initial abnormal newborn screening result.
Findings of an 11-deoxycortisol value greater than 15.0 ng/mL or 21-deoxycortisol greater than 4.0 ng/mL with elevated 17-OHP further support the abnormal newborn screening result and increase the diagnostic specificity. Clinical and laboratory follow-up is strongly recommended.
Day(s) Performed
Monday through Saturday
Report Available
1 to 3 daysTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82542
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CAH2T | CAH Newborn Screen, BS | 57086-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
42207 | 17-OH Progesterone | 38473-5 |
42208 | Androstenedione | 53343-0 |
42209 | Cortisol | 53345-5 |
42210 | 11-deoxycortisol | 53338-0 |
42211 | 21-deoxycortisol | 53341-4 |
42212 | (17OHP+Androstenedione)/Cortisol | 53336-4 |
42213 | 11-deoxycortisol/Cortisol | No LOINC Needed |
BG688 | Birth Weight (grams, XXXX) | 8339-4 |
BG689 | Time of Birth (24hr time, XX:XX) | 57715-5 |
BG690 | Gestational Age (weeks, XX.X) | 76516-4 |
42206 | Reviewed By | 18771-6 |
42214 | Interpretation (CAH2T) | 46758-9 |
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.