title: Urine benzodiazepines screening of involuntarily drugged and robbed or raped patients.
abstract: OBJECTIVE
  This study involved 35 patients who claimed to have been drugged before being robbed or raped, despite urine negative toxicologic screening by immunoenzymatic methods. The urines were frozen for further investigations, including enzymatic hydrolysis of urinary conjugates, liquid-solid extraction and, finally, immunoenzymatic screening of concentrated urine extract.
  
  
  METHODS
  Urine benzodiazepines were analyzed by immunoenzymatic assay before and after enzymatic hydrolysis combined with extraction.
  
  
  RESULTS
  On direct immunoenzymatic screening, 17 of the 35 urine samples were benzodiazepine positive. Enrichment of preserved specimens improved the detection threshold from 200 ng/mL to 50 ng/mL and 10 of the 18 negative urines became positive.
  
  
  CONCLUSIONS
  This method allowed us to demonstrate the benzodiazepines in half of previously negative urine samples. Benzodiazepine screening is particularly problematic because of low dosage, rapid elimination, failure to detect conjugated metabolites by immunoenzymatic reagents and high threshold of sensitivity for certain substances.
authors.affiliation: Laboratoire de Toxicologie, Hôpital Hôtel-Dieu, Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Boussairi
authors.forename: J P
authors.initials: JP
authors.lastname: Dupeyron
authors.forename: B
authors.initials: B
authors.lastname: Hernandez
authors.forename: D
authors.initials: D
authors.lastname: Delaitre
authors.forename: L
authors.initials: L
authors.lastname: Beugnet
authors.forename: P
authors.initials: P
authors.lastname: Espinoza
authors.forename: O
authors.initials: O
authors.lastname: Diamant-Berger
mesh_terms: D000293:Adolescent; D000328:Adult; D001569:Benzodiazepines / Q000506:poisoning / Q000652:urine*; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D013287:Illicit Drugs / Q000032:analysis; D007124:Immunoenzyme Techniques; D008297:Male; D010076:Oxazepam / Q000737:chemistry; D011041:Poisoning / Q000175:diagnosis* / Q000378:metabolism; D011902:Rape; D012680:Sensitivity and Specificity; D013800:Theft
chemical_list: D013287:Illicit Drugs; D001569:Benzodiazepines; D010076:Oxazepam