355 - Implementation of a Real-Time Urine Immunoassay for Fentanyl at a Children’s Hospital

1401 urine drug screens were performed over 6 months, and 53 (3.8%) were positive for fentanyl. Confirmatory testing was sent on 51 samples from 50 patients. Both unconfirmed samples were known by history to have fentanyl intake. There was 1/52 (2%; 95%CI 0.05-10%) false positive result which was judged due to ciprofloxacin cross-reactivity. Of the 49 confirmed true positives, 43% were ordered in ICUs, 35% in the ED, and 22% in general inpatient wards. The age range of confirmed true positive tests was 1 day to 25 years (median 4 years). Thirty-nine patients (80%) had been administered medical fentanyl prior to urine collection; none of these patients had fentanyl poisoning as the leading diagnosis at discharge. Of the 10 patients who were not given medical fentanyl prior to urine collection, the age range was 19 days to 18 years (6 between age 0-5; 1 between age 6-11; 3 between ages 12-18). Three out of 10 (30%) fentanyl poisoned patients were hospitalized in the ICU; one child died from fentanyl poisoning.



Conclusion(s): Six fentanyl poisonings were detected among children less than 6 years in 6 months, with one death. This fentanyl assay performed well in our population with a false positive rate of only 2%. A highly specific test is important to reduce misdiagnosis and inappropriate activation of child protection responses. We cannot determine a false negative rate as confirmatory testing is not done on negative tests. This fentanyl assay may perform differently in different laboratory and clinical settings. A reliable test for the timely detection of fentanyl poisoning in children appears valuable amid a tragic epidemic.