Introduction Case 1 Case 2 Case 3 Case 4 Case 5 Case 6 References

The Patient Scenario
A new patient is referred by his family physician to a pain management practice. The patient complains of moderate-to-severe low back pain as a result of a motor vehicle collision one year ago. His pain is rated “8/10” on the numeric pain scale using OTC anti-inflammatory medication. He is assessed, using the Opioid Risk Tool (ORT), at low risk of drug abuse, misuse, and addiction. The pain specialist physician conducts baseline Point of Collection/Care (POC) urine testing prior to writing a prescription for a controlled substance (CS) for chronic pain.


The Test

Point of Collection/Care (POC) Immunoassay Test Panel, including “opiates”

The Test Results
The test is negative for all analytes except opiates.

The Test Interpretation
The test result (positive opiate) appears to be in conflict with your original assessment of risk.

Which of the following would not explain the results?






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The Physician-Patient Communication
The physician discusses the test results with the patient. The patient denies use of any illicit or unprescribed licit drugs for the treatment of his back pain.

What would you do next?





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POC urine test results are qualitative and often represent the presence of members of classes of drug rather than specific drugs. Unless the POC test is specific for a specific analyte (ie, oxycodone or methadone) test results cannot differentiate which member of the class that was found.

The Physician's Next Step
The physician orders a comprehensive urine drug test to try and identify the cause of the positive result.

The Test Results
The test results are positive for both codeine and morphine, at moderate levels: codeine 1,500 ng/mL and morphine 1,000 ng/mL.

All of the following can explain the UDT results except he took:




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Although codeine metabolism can account for the presence of morphine, morphine metabolism cannot account for codeine. Due to impure starting materials, illicit heroin often contains variable amounts of codeine and so is consistent with these results. The definitive marker for heroin use, 6-monoacetylmorphine (6-MAM) is often not seen in urine samples due to rapid and spontaneous conversion to morphine. It is important to note, simply repeating the original test and obtaining the same result is not “confirmation” of results. This simply establishes repeatability. It is also important to know “why” the result is positive.

Final test results are confirmed as reported.

What would you do next?




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Codeine use can lead to positive results for codeine alone, codeine plus morphine, and, less commonly, morphine alone. The lab may be useful in helping to determine co-use versus metabolite presence in any sample result. In some cases, small amounts of hydrocodone can be found in samples containing large quantities of codeine. The test results may also be interpreted as a result of remote (ie, >12 hour) heroin use.

The Physician-Patient Communication
The physician discusses the confirmatory test results with the patient.

After a lengthy discussion, the patient mentions that he recently had dental work and the oral surgeon prescribed an antibiotic and tablets for pain. In fact, he says, his medication is in his car. The doctor requests the patient to bring his medication into the office to confirm exactly what type of drug the patient is taking.

Upon examination of the medication, it becomes apparent that the patient was prescribed acetaminophen with codeine for treatment of his dental pain. The patient was unaware that he was taking a codeine-containing product.

Use of codeine-containing preparations will usually result in urine testing positive for morphine and codeine.

The legitimate presence of any analyte being tested for makes identification of misuse of that drug, if it occurs, difficult. For similar reasons, the chronic use of codeine is to be avoided.

The Final Outcome
It is determined after additional assessment that the patient is an appropriate candidate for a trial of opioid therapy to treat his musculoskeletal low back pain. He is given a trial prescription for one month with instructions to book a follow-up appointment.

It is essential for the prescriber to obtain a full medication profile including prescribed medications, over-the-counter medications, herbal agents, and recreational drug and alcohol use prior to urine drug testing in order to correctly interpret the results.

The practitioner may prefer to use a non-judgmental, open-ended communication style to obtain accurate and comprehensive information from the patient.

Do not over-interpret results. Over-interpretation of urine test results places the patient and physician at medicolegal risk.
Always be cautious in the interpretation of diagnostic test results.

Communicate with your patient and when necessary, your laboratory support personnel to ensure that the correct patient-centered decision is made.

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Case 2:
High-risk patient

Case 3:
Activity-related pain

Case 4:
Escalating opioid doses

Case 5:
Opioid-dependent
pain patient

Case 6:
Comorbid depression & anxiety