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Overview of Drug g Testing g Methods Anthony Albanese, Albanese M M.D. D Clinical Associate Professor of y y Medicine & Psychiatry UC Davis Medical School Director, Chemical Dependency & H Hepatology t l P Programs Sacramento VA Medical Center DISCLAIMER • No financial interests to disclose (UNFORTUNATELY) Commonly asked liver questions • Is it safe to use naltrexone in HCV patients? – Black box..but yes in non decompensated pt pt. if you monitor LFT’s LFT s. • Is it safe to use statins in patients will alcoholic liver disease or hep c? … yes in non decompensated pt. if you monitor LFT s. LFT’s • Monitoring interval? Baseline, 1 week, 1 month, th 4 months th Prevalence of HCV in Select Populations Illicit drug users ~ 300,000 ((80%–90%))2,3 Alcoholics ~ 240,000 (11%–36%)5 Incarcerated ~ 330,000 to 860,000 (16%–41%)1 Female Male HIV-infected ~ 300,000 (30%)4 Homeless ~ 175,000 (22%)7 37% 63% Veterans ~ 280,000 (8%)8 Living below poverty level ~ 940,000 (3.2%)6 Children (6–18 years old) ~ 100,000 (0.1%)9 Adapted Ad d ffrom: 1 1. CDC CDC. MMWR. MMWR 2003;52(RR-1):1-33; 2003 52(RR 1) 1 33 2 2. Edli Edlin B B. Hepatol. H t l 2002;36(5 2002 36(5 suppll 1) 1):S210-S219; S210 S219 3 3. NHSDA R Report 2003 2003; 4. Poles M, et al. Clin Infect Dis. 2000;31:154-161; 5. LaBrecque D, et al. Hepatitis C Choices. 2002:7-15; 6. Alter M, et al. N Engl J Med. 1999;341:556-562; 7. Nyamathi A, et al. J Gen Intern Med. 2002;17:134-143; 8. Bräu N, et al. Am J Gastroenterol. 2002;97:2071-2078; 9. Jonas M. Hepatol. 2002;36(5 suppl 1):S173-S178. OBJECTIVES • Discuss role of Medical Review Officers (MRO) • Discuss limitation of screening test • Review options for forensic testing • Discuss the role of drug testing in the treatment of addictive disease Brief History • 1981 – US Department of Defense instituted periodic and random drug testing of all servicemen. • 1984 – Nearly 80% Fortune 500 companies were conducting pre-employment drug testing. • 1988 – Resulting from Executive Order# 12564, and congressional public law # 11-71 Department of Health and Human Service Guidelines published- require a licensed physician to be responsible – MRO’s’ are born!, DOT involved by 1989. Swotinsky,R, et al. J. Occ Med; 32;10;1990 pp 1003-1008 Why Do We Need MRO’s? MRO s? • To protect the rights of the prospective employee ( not a patient). • To protect the interests of the prospective employer – the client. • To T oversee and d review i th the iintegrity t it off th the forensic testing procedure. • To pursue life, liberty, happiness, and justice for all! How ? 4 of the “NIDA NIDA 5” 5 drugs tested have legitimate uses • Cocaine • Dronabanol- anti nausea, appetite stimulant • TACTAC topical anesthetic, anesthetic vasoconstrictor • Opiates • Pain relief – not 6-MAM • Amphetamines • Depression, ADHD, narcolepsy • No legitimate use • Marijuana • Phencyclidine (PCP) Furthermore…… Screening tests can yield false positive results ( less common in 3rd EMIT) • Amphetamine- ephedrine, pseudoephedrine, phenylephrine, selegiline, chlorpromazine, trazodone, buproprion amantadine buproprion, amantadine, ranitidine ranitidine, fluoxitine • Marijuana j – Ibuprofen, p , naproxyn, p y , efavirenz,, protonix p promethazine, tolectin • OpiatesO i t Rifampin, Flouroquinolones, quinine, poppy seeds, chlorpromazine, dolobid Medical Letter Vol 44, August 10,2002 Screening g tests can yyield false positive results • Phencyclidine- Ketamine, Dextromethorphan, Venlafaxine, diphenhydramine, meperidine • Cocaine – coca leaf tea, ? Others ? • Alcohol- in urine, yeast + sugar = EtOH • http://www.askdocweb.com/falsepositives.html Common Screening Methods: Immunoassay • Radioimmunoassayy ((RIA)) & Enzyme-Linked y Immunosorbent Serologic Assay (ELISA) – heterogeneous assays • Enzyme y Immunoassayy (EIA) ( ) or Enzyme y Multiplied Immunoassay Technique (EMIT), Cloned Enzyme Donor Immunoassay (CEDIA) – detect certain wavelengths of light when enzyme links antigen drug to antibodytib d homogeneous h assays. • Fluorescence Polarization Immunoassay (FPIA)- Based on competitive binding of labeled and unlabeled antigen t the to th antibody tib d complex l • Kinetic Interaction of Microparticles in Solution (KIMS)– latex microspheres coated with drug and cause turbidity when Ab added dd d unless l d drug concentration t ti in i sample l inhibits i hibit agglutination. l ti ti The Gold Standard Confirmatory test • Gas chromatography/ g p y mass spectroscopy (GC/MS) • Liquid chromatography/ mass spectroscopy ( LC/MS) • Chromatography separates compounds & detects isomers • Mass spectroscopy uses electron impact pact o or cchemical e ca ionization o at o to identify the compound. Concentration determined by determining ratio of tested drug to internal standard. Testing g Methods • Urine- accepted as the standard for the “5” drugs but not alcohol. alcohol Accepted for DOT and government workers/contractors. GC/MS confirmation available. Problems include adulteration, dilution, “shy bladder”. I Inexpensive i - ~ $15/ ttestt • Oral Fluid- not yet accepted for DOT/government applications. li ti LC/MS confirmation fi ti available. il bl All collections observed. Less problem with adulteration. Cost ~ $30/test • Sweat – not yet accepted for most applications. Patch worn for 24hr then read. Confirmation tests more difficult. TIME TABLE for Ui d Urine drug screening i Test drug + test Amphetamine 1000 ng/ml duration 2-3 days Methamphetamine 500 ng/ml Amphetamine 500 ng/ml Cocaine 300ng/ml 2-3 d up to 8 d Marijuana 50 ng/ ml 1-7 d up to 30d Opiates *2000/15,000 ng/ml 1-3 days Phencyclidine 25 ng/ml 7-14 days The Medical Letter Vol 44 (W1137A) August 19, 2002 Hair Testing g • Head hair g grows about ½ inch/month. Hair testing can give a record of use over a period of months, not days. • Tests T can be b confirmed fi db by GC/MS GC/MS. • There is some question of ethnic bias as dark hair concentrates metabolites better than light hair. pe s e ~ $ $150-200/test 50 00/test – “onezees” o e ees • Expensive available. • Not approved for DOT/ government. Collection Process (Urine testing) • D Donor iis positively iti l id identified tifi d with ith photo h t ID by collector and asked to remove outer garments t and d leave l purse or b briefcase. i f List of current meds requested. • Donor washes hands, enters bathroom with no running water and “bluing” in toilet. Provides sample ( ~45 ml ) into container. • Collector insures temp is 90 -100 F and places sample in specimen bottles (30ml & 15ml) and seals them. Donor signs tape & lab slip, before changing. Collection Process (Urine testing) Shy Bladder” Bladder “Shy • Donor must provide 45ml of urine for a valid test test. If unable unable, may be given up 40 oz of water (1.2 liters) over a period of 3 hrs. • If no pre-existing i ti medical di l condition diti tto explain reason, MRO reports “refusal to t t” If short test”. h t term t conditionditi “ “cancelled” ll d” • If permanent or long-term condition noted & this is pre-employment, return to duty or f/u test, clinical hx and physical must be performed for evidence of illicit drug use. Lab testing g ((Urine)) • Collector signs lab slip gives specimen to courier Lab officer signs slip courier. slip, ensuring intact “chain of custody”. • Specimen is tested for creatinine creatinine, specific gravity (SG), pH, and adulterants. • Possible adulterants include nitrites nitrites, hexivalent chromium, halogens, glutaraldehyde, g y , surfactants and other oxidizing agents. Interfering Medications (Urine testing) • • • • • Amiodarone Ciprofloxacin Gi Griseofulvin f l i Mefenamic Acid Metronidazole • Salicyluric Acid (metabolite of ASA) • Sulfasalazine • Sulindac • Tolmentin Lab Testing (Urine) • Creatinine < 20mg/dl but > 2 mg/dl is a dilute sample and requires SG test • SG > 1 1.0010 0010 but < 1 1.0030 0030 is a dilute specimen. • Creatinine C ti i < 2 2mg/dl /dl and d SG < 1 1.0010 0010 or SG > 1.020 is a substituted specimen. • Creatinine < 2 & SG >1.0010 and <1.020 or creatinine > 2 & SG < 1.0010 are invalid specimens Lab Testing (Urine - pH) • pH < 3 or >11 is an adulterated specimen • pH > 3 & < 4.5 or >9.0 and < 11 is an invalid specimen. specimen Urine (with bacteria) store higher than room temp can produce ammonia and raise pH pH. • For pH 9.0-9.5 -MRO must discuss with d donor tto see if there th is i an explanation. l ti MRO may report result, cancel, or cancel and d requestt di directt observation b ti retest. t t Reporting p g Process • Negative samples reported to MRO review company as such. h P Positive iti specimen i confirmed by GC/MS or LC/MS. • MRO makes k a reasonable bl effort ff t tto contact t t donor. After positive identification, discusses result result, looking for medical explanation and intact chain of custody. Donor may request retest (of sample “B”B at own expense- $ fronted by employer). • Reports finding as positive, negative, canceled, unsuitable, or adulterated. MRO Interview “Essential Elements” 1 Contact –Donor 1. Donor generally has ~ 72 hrs to get back to MRO after initial contact attempt If no contact MRO informs attempt. employer of need to contact donor. 2 MRO identifies self 2. self, and obtains positive ID from Donor. 3 MRO informs 3. i f Donor D off results lt and d records spontaneous comments. MRO Interview “Essential Elements” 4 Miranda Information “ I need to let you know that 4. I am the MRO, not your physician. The information you give me may not be kept confidential.” 5. Discuss collection process and chain of y custody. 6. Elicit information to determine whether there is a medical explanation for the result 7 Offer Retest Rights – don 7. don’tt delay initial report to company if retest requested. MRO Interview Interview- no contact 1. Donor declines interview – report p result 2. MRO can not reach donor. MRO informs Designated Employer Representative (DER) of need to contact. Donor has 72 hrs to contact MRO. 3. MRO and DER can’t reach donor. MRO may report result after 10 days days. Department p of Transportation p (DOT) 49 CFR 40 • Federal Aviation Administration ( FAA) • Federal Motor Carriers Safety Administration (FMCSA) • Federal Railroad Administration (FRA) • Federal Transit Administration (FTA) • Coast Guard • Government Contractors (DOD DOE, (DOD, DOE NASA, NASA NRC) www.dot.gov/ost/dapc/ Department of Transportation (DOT) 49 CFR 40 • DOT has established “safety safety sensitive sensitive” positions (pilot vs baggage handler). • MRO must still report results as per protocol, but may issue a “safety issue” letter of concern depending on circumstances. • www.dot.gov/ost/dapc/ d t / t/d / for f regulations l ti What next ? • A lost chance for employment may be a prime i opportunity t it for f a brief b i f intervention. i t ti • In some “Drug Free Workplace” environments (hospitals), pre-employment “positives” must be referred to the state board or diversion program. • Donors must be referred to a substance abuse professional (SAP). This may be through g the company p y EAP. MRO vs SAP • SAPs are generally licensed physicians, social workers, or psychologists who evaluate and treat addictive illness. • Beware of conflicting roles if you’re program p g is contracted for SAP duties with a corporation for whom you are acting as an MRO. Drug Testing in Hospitals & Addiction Treatment Programs • Important to obtain biological confirmation of the history. • Offers Clinician the opportunity to provide immediate feedback to patient. • Provides P id b basis i ffor th therapeutic ti iintervention t ti when indicated. • Validation of Sobriety . Drug Testing in Hospitals & Addiction Treatment Programs • Important to realize that results are often followed by comment “for medical purposes only” – indicating no chain of custody, and no confirmatory testing. • Many facilities use the 2nd generation screening tests (for cost savings) so false positives occur – primarily with amphetamines, PCP, MJ, opiates, and benzos benzos. • OK to ask pts about positive results, but confirm test results with GC/MS ( on sample in lab) before being confrontational. Questions & Discussion