Evaluation of an Enzyme Immunoassay for the Detection of Methadone Metabolite EDDP [2‐Ethylidene‐1, 5‐Dimethyl‐3, 3‐Diphenylpyrrolidine] in Urine. Issue 2 (6th January 2014)

• Record Type: Journal Article
• Authors: Wolf, Carl E.; Goldstein, Ashley; Poklis, Justin L.; Poklis, Alphonse
• Is Part Of: Journal of clinical laboratory analysis. Volume 28:Issue 2(2014:Mar.)
• Page Start: 136
• Page End: 140
• Publication Date: 2014-01-06
• Subjects: Diagnosis, Laboratory -- Periodicals; Medical laboratory technology -- Periodicals; 616
• DOI: 10.1002/jcla.21657
• Languages: English
• ISSNs: 0887-8013

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jcla21657-sec-0010" sec-type="section"> <title>Background</title> <p>We evaluated a new EDDP [2‐ethylidene‐1, 5‐dimethyl‐3, 3‐diphenylpyrrolidine] enzyme immunoassay (EDDPI; Lin‐Zhi International, Inc., Sunnyvale, CA) for the detection of this primary methadone urinary metabolite.</p> </sec> <sec id="jcla21657-sec-0020" sec-type="section"> <title>Methods</title> <p>All specimens were tested with two different cutoff calibrators at 150 and 300 ng/ml EDDP on an ADVIA 1200 Chemistry System auto‐analyzer. Controls containing 0, −25% (negative control), and +25% (positive control) of the cutoff calibrators (Lin‐Zhi) were analyzed with each batch. All urine specimens were then analyzed by high‐pressure liquid chromatography/ mass spectrometry/mass spectrometry (HPLC‐MS/MS) for EDDP.</p> </sec> <sec id="jcla21657-sec-0030" sec-type="section"> <title>Results</title> <p>Approximately, 42% (151) of the 362 specimens yielded positive results by the EDDP assay at 150 and/or 300 ng/ml cutoff values. Of these specimens, HPLC‐MS/MS confirmed the presence of EDDP > 25 ng/ml in all 151 specimens. No specimen yielding negative EDDPI results contained EDDP by HPLC/MS/MS. At 150 ng/ml cutoff, the EDDPI demonstrated a sensitivity of 1.00, a specificity of 0.986, and an overall agreement of HPLC/MS/MS of >99%. At 300 ng/ml cutoff, the EDDPI demonstrated a sensitivity of 1.00, a specificity of 0.959, and an overall agreement of HPLC/MS/MS results of 97.5%.</p> </sec> <sec id="jcla21657-sec-0040" sec-type="section"> <title>Conclusion</title> <p>The Lin‐Zhi EDDPI provides a precise, reliable method for the routine detection of methadone metabolite in urine specimens, particularly in pain management compliance testing.</p> </sec> </abstract>