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HelpTest Code COKEM Cocaine and Metabolites Confirmation, Meconium
Reporting Name
Cocaine and Metabolites, Confirm, MUseful For
Detecting in utero drug exposure up to 5 months before birth
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
MeconiumOrdering Guidance
For chain-of-custody testing, order COKMX / Cocaine and Metabolite Confirmation, Chain of Custody, Meconium.
Specimen Required
Supplies: Stool container, Small (Random), 4 oz (T288)
Container/Tube: Stool container
Specimen Volume: 1 g (approximately 1 teaspoon)
Collection Instructions: Collect entire random meconium specimen.
Specimen Minimum Volume
0.3 g (approximately 1/4 teaspoon)
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Meconium | Frozen (preferred) | 21 days | |
| Refrigerated | 21 days | ||
| Ambient | 72 hours |
Reject Due To
| Grossly bloody | Reject; Pink OK |
| Stool Diapers |
Reject |
Reference Values
Negative
Positives are reported with a quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) result.
Cutoff concentrations for LC-MS/MS testing:
Cocaine: 20 ng/g
Benzoylecgonine: 20 ng/g
Cocaethylene: 20 ng/g
m-Hydroxybenzoylecgonine: 20 ng/g
Day(s) Performed
Monday through Sunday
CPT Code Information
80353
G0480 (if appropriate)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| COKEM | Cocaine and Metabolites, Confirm, M | 69008-1 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 31859 | Cocaine | 69009-9 |
| 31860 | Benzoylecgonine | 69010-7 |
| 31861 | Cocaethylene | 69011-5 |
| 31862 | m-Hydroxybenzoylecgonine | 69012-3 |
| 31864 | Interpretation | 69050-3 |
| 31865 | Chain of Custody | 77202-0 |
Clinical Information
Cocaine is an alkaloid found in Erythroxylon coca, which grows principally in the northern South American Andes and, to a lesser extent, in India, Africa, and Java.(1) Cocaine is a powerfully addictive stimulant drug. Cocaine abuse has a long history, is rooted in the drug culture in the United States,(2) and is 1 of the most common illicit drugs of abuse.(3,4) Cocaine is rapidly metabolized primarily to benzoylecgonine, which is further metabolized to m-hydroxybenzoylecgonine (m-HOBE).(1,5) Cocaine is frequently used with other drugs, most commonly alcohol, and the simultaneous use of both can be determined by the presence of the unique metabolite cocaethylene.(4)
Intrauterine drug exposure to cocaine has been associated with placental abruption, premature labor, small for gestational age status, microcephaly, and congenital anomalies (eg, cardiac and genitourinary abnormalities, necrotizing enterocolitis, and central nervous system stroke or hemorrhage).(6)
The disposition of drug in meconium, the first fecal material passed by the neonate, is not well understood. The proposed mechanism is that the fetus excretes drug into bile and amniotic fluid. Drug accumulates in meconium either by direct deposition from bile or through swallowing of amniotic fluid.(7) The first evidence of meconium in the fetal intestine appears at approximately the 10th to 12th week of gestation and slowly moves into the colon by the 16th week of gestation.(8) Therefore, the presence of drugs in meconium has been proposed to be indicative of in utero drug exposure during the final 4 to 5 months of pregnancy, a longer historical measure than is possible by urinalysis.(7)
Interpretation
The presence of any of the following: cocaine, benzoylecgonine, cocaethylene, or m-hydroxybenzoylecgonine, at 20 ng/g or more, is indicative of in utero drug exposure up to 5 months before birth.
Cautions
No significant cautionary statements
Method Description
Meconium is mixed with internal standard and extracted with methanol. The methanolic extract is further processed by solid-phase extraction. The extract is analyzed by liquid chromatography tandem mass spectroscopy.(Unpublished Mayo method)