Investigations
Your Organisational Guidance
ebpracticenet urges you to prioritise the following organisational guidance:
GeneesmiddelenverslavingPublished by: Domus Medica | SSMGLast published: 2011Assuétude aux médicamentsPublished by: Domus Medica | SSMGLast published: 20111st investigations to order
Addiction Severity Index (ASI)
Test
Structured interview to assess the patient's problem severity in seven areas of functioning: medical status, employment/support status, drug use, alcohol use, legal status, family/social relationships, and psychiatric status. Addiction Severity Index Opens in new window Based on subsets of items that have been found to be consistently associated with treatment outcome.
The ASI is the most widely used clinical instrument in addiction treatment programmes in the US, and is used for treatment planning and follow-up.[70] A brief version of the ASI (ASI-Lite) and a computerised version are also available.
Result
composite scores ranging from 0 (minimum severity) to 1 (maximum severity) are provided in each area to reflect opioid use disorder severity in the last 30 days. A higher score on the ASI indicates a greater need for treatment
clinical opiate withdrawal scale (COWS)
Test
A clinician-administered tool used to assess the severity of opioid withdrawal; may help to standardise documentation of signs and symptoms of withdrawal as an adjunct to clinical assessment. May be used as part of the assessment as to when to safely initiate drug treatments for opioid use disorder to avoid the risk of precipitated withdrawal.[69][74] [ Clinical Opioid Withdrawal Scale (COWS) for adults and adolescents Opens in new window ]
Result
it includes 11 items, each scored individually and then summed to produce a total score that indicates withdrawal severity. A higher score indicates more severe withdrawal
urine or saliva drug screen
Test
A drug screen should be ordered initially if there is a clinical suspicion of drug use.[69] Testing for other substances such as cocaine, benzodiazepines, and methamphetamine in addition to testing for opioids is clinically important because these and other substances, especially benzodiazepines, can complicate treatment for opioid use disorder. Furthermore, co-occurring substance use disorders will require their own separate treatment plans.[69]
The Drug Screen 9 (DS-9) is one of the more common immunoassays, and tests a urine sample for opioids (oxycodone, hydrocodone, hydromorphone, morphine, and codeine only), cocaine, marijuana, benzodiazepines, phencyclidine, amfetamines, and barbiturates.
The test will report 'positive' for opioids in people who misuse opioids; however, it will not specifically identify which opioid has been taken.
A point of care test (POCT) on a urine or saliva specimen may alternatively be performed as the initial screening test in certain circumstances (e.g., in primary care). The principal advantage of POCTs over laboratory screening tests is that the results are available in approximately 10 minutes. This fast turnaround allows practitioners to discuss the results with the patient during that office visit, and make clinical decisions and act appropriately that day. POCTs are also inexpensive and relatively easy to use with minimal training. Despite these benefits, laboratory testing is more accurate overall, and provides quantitative estimates of drugs and their metabolites.[71]
Routine immunoassays do not usually detect synthetic or semisynthetic opioids (e.g., fentanyl, methadone, meperidine, tramadol) and so a positive urine or saliva screen should be followed by a confirmatory urine test.
Result
positive (cut-off limit 300 nanograms/mL)
gas chromatography-mass spectroscopy (GC-MS)
Test
Positive urine or saliva screen should be followed by a confirmatory urine test due to opioid sensitivity limitations and because certain drugs (e.g., antibiotics) can interfere with the test and produce false-positive results.
Opioid confirmation urine test by GC-MS is the most specific and sensitive test for identifying opioids.
Will identify the specific opioid in the urine.
There are specialised GC-MS tests to detect fentanyl and buprenorphine.
It is important to note that heroin will be detected as morphine in the urine, and a specific metabolite of heroin (i.e., 6-monoacetylmorphine) that is only detectable for a few hours after heroin use has to be identified to distinguish heroin from morphine use.
Result
positive (cut-off limit 150 nanograms/mL)
serum electrolytes
Test
May be deranged secondary to malnutrition associated with opioid use.
Result
normal or deranged
FBC
Test
Useful to identify presence of infections from illicit intravenous drug use and to evaluate baseline for follow-up as part of the general haematological profile.
Result
WBC count is normal or elevated in presence of infections
urea/creatinine
Test
Evaluation of renal function is necessary for dosing of pharmacotherapy.
Result
normal or elevated in presence of renal impairment
LFTs
Test
Evaluation of liver function is necessary for dosing of pharmacotherapy, as well as to direct appropriate intervention for existing liver disease.
LFTs are often elevated due to hepatitis or from injury to the liver caused by contaminants in the injected opioid.[1]
Result
normal or elevated in presence of hepatic impairment
hepatitis serology
Test
Testing for hepatitis B and hepatitis C infection is recommended in all patients by the American Society of Addiction Medicine.[66]
Illicit intravenous drug use is associated with hepatitis B and C infection.
Result
normal or positive in presence of hepatitis B virus or hepatitis C virus infection
HIV serology
Test
Testing for HIV infection is recommended in all patients by the American Society of Addiction Medicine.[66]
Illicit intravenous drug use is associated with HIV infection.
Result
normal or positive in presence of HIV infection
purified protein derivative (PPD) skin test
Test
Testing for tuberculosis infection is recommended in all patients by the American Society of Addiction Medicine.[66]
Immunity is decreased in intravenous drug users, leading to either reactivation of latent tuberculosis or increased susceptibility to infection.
A positive result indicates tuberculosis exposure.
Result
normal or positive (5-10 mm) in presence of tuberculosis infection; A result of 10 mm or more is considered to be positive in intravenous drug users. If HIV-positive, a result of 5 mm or more is considered to be positive
Investigations to consider
rapid plasma reagin
Test
Testing for sexually transmitted infections such as syphilis should be considered.
Intravenous drug use has been associated with a positive rapid plasma reagin test.
Result
normal or positive in presence of syphilis
blood cultures
Test
Indicated if there are signs or symptoms suggestive of septicaemia (e.g., high fever, altered mental state, and vital sign changes) or infective endocarditis (e.g., fever with heart murmur).
Result
normal or positive for staphylococci, streptococci, or Pseudomonas aeruginosa
beta human chorionic gonadotrophin (beta-hCG)
Test
All women of childbearing potential should be tested for pregnancy.[66]
It is important to rule out pregnancy for appropriate use of pharmacotherapy, and to evaluate the risk of neonatal opioid withdrawal syndrome.
Result
normal or positive in pregnant women
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