A combined HPLC-immunoenzymatic comprehensive screening for suspected drug poisoning in the emergency department.

OBJECTIVE To review the results of a comprehensive drug screening as first line diagnostic tool in patients attending an emergency department for suspected drug poisoning. METHODS A comprehensive drug screening was carried out in plasma or urine, or both, of 310 patients combining an HPLC multidrug profiling system and a fluorescence polarisation immunoassay. RESULTS In 64.2% of cases the screening confirmed the diagnosis of drug poisoning, in 13.9% suspected drugs were measurable at non-toxic concentrations, and in 21.9% no drugs were found. The suspected drugs were fully confirmed in a minority of cases, (symptomatic patients: 28.2% compared with asymptomatic: 16.5%). Symptomatic patients were less likely to have at least one suspected drug (29.6% compared with 57.7%; p<0.001), and more likely to have at least one unsuspected drug found at analysis (17.4% compared with 3.1%; p = 0.005). In 5% of patients, asymptomatic when first observed, one or more unsuspected drugs were found. In 6 of 29 patients, with suspected poisoning of an unspecified drug, the screening identified the specific drug and excluded acute intoxication in the remaining cases. CONCLUSION A rapid comprehensive drug screening adds to the diagnosis of patients with suspected drug poisoning, identifying unsuspected drugs in symptomatic patients and excluding drugs in asymptomatic subjects.