[Use of urine drug screening in the emergency department of a paediatric hospital]

Objective: To describe the situations in which urine drug screening is used in a Paediatric Emergency Department (ED). An analysis is also made on its potential usefulness on whether it changes the patient management, and if the results are confirmed by using specific techniques.

Methodology: A retrospective study was conducted on patients under the age of 18 attended in the ED during 2014 and in whom urine drug screening was requested. Depending on the potential capacity of the screening result to change patient management, two groups were defined (potentially useful and not potentially useful).

Results: Urine drug screening was performed on a total of 161 patients. The screening was considered not to be potentially useful in 87 (54.0%). This was because the clinical history already explained the symptoms the patient had in 55 (34.1%) patients, in 29 (18.0%) because the patient was asymptomatic, and in 3 (1.9%) because the suspected drug was not detectable in the screening. The drug screening results changed the patient management in 5 (3.1%) cases. A toxic substance was detected in 44 (27.3%). Two out of the 44 that were positive (2.1%) were re-tested by specific techniques, and presence of the toxic substance was ruled out in both of them (false positives).

Conclusions: Most of the drug screening tests are not justified, and it is very infrequent that they change patient management. It is very rare that the results are confirmed using more specific methods. Urine drug screening tests should be restricted to particular cases and if the result has legal implications, or if the patient denies using the drug, it should be followed by a specific toxicological study to provide a conclusive result.