Diagnostic performance of Triage for benzodiazepines: urine analysis of the dose of therapeutic cases.

We evaluated the diagnostic performance of Triage for benzodiazepines in 74 urine specimens from outpatients given therapeutic doses of benzodiazepines and compared the results of EMIT assays. Results obtained in all urine samples were confirmed using liquid chromatography-mass spectrometry (LC-MS). Overall agreement between results of Triage and EMIT assays was 73%. All of the Triage-positive samples were also positive by EMIT assays. Results of Triage and EMIT assays were different for 20 samples obtained from patients given thienodiazepines (etizolam, brotizolam, and clotiazepam) and nitrobenzodiazepines (nitrazepam, flunitrazepam, and clonazepam). LC-MS confirmed parent drugs in urine specimens, consistent with the prescriptions of drugs. The low agreement between Triage and EMIT results in this study might be due to low sensitivity of Triage for thienodiazepines. Thienodiazines are frequently prescribed benzodiazepines, and Triage panel is the most frequently used screening kit in Japan. It should be noted that negative results obtained by a Triage test might not mean the absence of thienodiazepines.