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Phosphatidylglycerol

Item Value
Approval req'd? No
Available Stat? Yes, available day and evening shift for inpatients only
Test code PGAG
Test group Fetal Lung Maturity
Performed by Parnassus Chemistry
In House Availability STAT: Test available day and evening shift for inpatients only
Routine: Day and evening shift only, seven days per week
Method Immune agglutination
Collection Instructions Specify if the specimen has been collected from drainage through the vagina by writing "diabetic" or "vaginal pool" on the requisition. Indicate time of collection on sample label.

Transport sample immediately to laboratory for testing. If delivery must be delayed or if sending from a remote site refrigerate sample and transport refrigerated
Container type Red top or Plastic tube
Amount to Collect 2 mL
Sample type Amniotic fluid
Preferred volume 2 mL fluid (sufficient for Lamellar Body Count as well)
Min. Volume 1 mL fluid
UCSF Rejection Criteria Sample received at room temperature > 1 hour after collection.
Processing notes Store at 2-8C up to 4 hours; if > 4 hours, store at -20C
Normal range
Present Mature
Synonyms PG
Stability Room temperature 1 hour, refrigerated 4 hours
Turn around times STAT 2 hours, Routine 4 hours
Additional information The PG test cannot be ordered without a lamellar body count (LBC) test. PG only orders will convert to an order for both the LBC and PG tests.

If ordered, the assay for PG will be performed in those settings where the lamellar body count (LBC) is in the transitional range (15-50 x 109/L), and in samples contaminated with blood, vaginal secretions or meconium. A positive PG assay in those settings is indicative of fetal lung maturity. The PG assay is unnecessary in mature specimens with a LBC > 50 x 109/L and is also unnecessary in samples with a LBC < 15 X 109/L, as PG is typically absent in samples with a low LBC.

Note that phosphatidylglycerol (PG) is usually not detectable in significant amounts before 35 weeks gestation. The presence of PG is indicative of fetal lung maturity, however, absence of PG does not necessarily predict development of RDS. Most amniotic fluid samples with LBCs in the transitional range will be negative for PG.

Samples received from Moffitt-Long Hospital will be treated as stats between the hours of 7:00am and 11:00pm, processed immediately and given to Chemistry. Samples received from outside hospitals between 7am -11pm will also be treated as stats whereas those received at night between 11pm-7am will be held for assay until the morning shift. Requests for stat testing on such samples will be performed only with lab medicine approval. Inform the technologist whenever the word "vaginal pool" is recorded on the request slip.
LOINC code 20499-0
Last Updated 3/24/2013 8:14:25 PM
Entry Number 838
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