Congenital Adrenal Hyperplasia (CAH) Newborn Screening, Blood Spot
Method Description Describes how the test is performed and provides a method-specific reference
A 3/16-inch disk is punched out of the blood spot into a 96-well filter plate. Water plus 10% acetone containing the internal standards d817-OHP, d7-androstenedione, d3-cortisol, d2-11-deoxycortisol, and d8-21-deoxycortisol, is added to the filter plate. The punched disks are allowed to elute at room temperature on an orbital shaker for 30 minutes. The blood spot eluate is then centrifuged into a 96-well round bottom plate. Extraction of steroids from the blood spot eluate is performed by turbulent flow chromatography and analysis is by electrospray liquid chromatography-tandem mass spectrometry (LC-MS/MS). The concentration of 17-hydroxyprogesterone (17-OHP), androstenedione, cortisol, 11-deoxycortisol, and 21-deoxycortisol are established by comparison of their ion intensity to that of their respective internal standards.(Lacey JM, Magera MJ, Di Bussolo JM, et al: Development of a method for the determination of congenital adrenal hyperplasia [CAH] by turbulent flow chromatography and LC-MS/MS. 2007 AACC Annual Meeting, San Diego, CA, July 2007)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 8 a.m., Friday and Saturday; 4 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test