DETECTION OF COCAINE, NORCOCAINE, AND COCAETHYLENE IN THE MECONIUM OFPREMATURE NEONATES

Our objective was to investigate the methodologic detection of cocaine abuse during pregnancy by determining the viability of meconium analy sis for cocaine and its metabolites using chromatographic procedures a s an alternative to urine testing using enzyme multiplied immunoassay technique. Our design was as follows: meconium and urine were taken fr om 106 very low birthweight premature babies. Meconium analysis for co caine and its metabolites using extraction and chromatographic analysi s was compared with the criterion standard immunoassay testing for uri ne. The work was carried out at The University of Chicago Hospital, De partment of Pediatrics and the University of Illinois at Chicago, Depa rtment of Pharmacodynamics. Our patients were very low birthweight, pr emature babies (mean birthweight 1109 g; mean gestational age 29.1 wee ks). Gender was evenly divided between male and female. The outcome me asures were as follows: two active metabolites, norcocaine and cocaeth ylene, were detected in the meconium, but not in the urine, of some of the neonates. Determination of cocaine exposure in the newborn influe nced assignment of babies in research studies as well as psychosocial evaluation and subsequent treatment of the neonate. Our results were: of the 106 meconium samples analyzed, 21 (19.8%) were positive for coc aine (n = 19, 0.24-0.78 mg/kg), norcocaine (n = 7, 0.10-0.56 mg/kg), c ocaethylene (n = 1, 0.12 mg/kg) or combinations thereof. Benzoylecgoni ne was not detected in any of the samples. Of the urine samples analyz ed by immunoassay, only 8 (7.5%) were positive for cocaine metabolites . We conclude that meconium is a better sample than urine for determin ing cocaine exposure in utero. The presence of two neuroactive metabol ites, norcocaine and cocaethylene, is reported, norcocaine for the fir st time. Immunoassay screening procedures for urinalysis are inadequat e because false-negative results are obtained.