Received: 15 January 2004Accepted: 1 July 2004Published online: 28 September 2004© Springer-Verlag 2004

An author’s reply to this letter is availableat http://dx.doi.org/10.1007/s00330-004-2469-z

Sir,We read with interest the paper byMeijer et al. [1] that attempts to sup-port the use of ultrasound in the de-tection of intestinal drug smuggling.While the authors report and empha-size the positive predictive value ofthe sonographic evaluation, we be-lieve that a more clinically relevantanalysis is necessary.

The author’s stated goal was to“. . . investigate the value of abdominalultrasound for the detection of intesti-nal drug containers in air travelerssuspected of intestinal drug traffick-ing.” Although they conclude that ul-trasound is useful, their highly select-ed population may limit the applica-bility of their results to the use of ul-trasound as a medical screening test.If incarcerated, 84% of suspects ulti-mately passed packets. Given this ex-ceedingly high pretest probability, it isnot surprising that ultrasound correct-ly identified 97.6% of those carryingpackets. The more important questionthat is only alluded to is whether ultra-sound can exclude suspects? To re-duce the number of passengers inap-propriately incarcerated for days, thenegative predictive value of the testshould near 100%. The calculatednegative predictive value from thestudy data was only 77%. A test thatmerely enhances the ability to confirmtrue positives is less valuable since itdoes not identify the few patients whoare true negatives and should there-fore be released immediately.

Additionally, the current study failsto define an effective gold standardagainst which ultrasound can be com-pared. Commonly cited as an endpoint[2], there is no evidence to support the

supposition that three container-freestools assures that a passenger is not abody packer. In our experience, pack-ets can sometimes fail to pass despitethe passage of several container-freestools, even in patients receiving ag-gressive gastrointestinal decontamina-tion. Additionally, packets can fail tobe detected even by more sensitivemethods such as plain radiography orcomputed tomography [3]. Therefore,even though 84% of the study popula-tion was confirmed to have packets, itis possible that the actual percentagewas even higher. This would furtherlower the negative predictive value,making the screening exam even lessuseful.

In summary, the authors report anew indication for handheld ultraso-nography. Unfortunately, it does notappear that this will be a useful ad-junct for the screening of suspectedgastrointestinal drug smugglers if thegoal is to obviate the need for the de-tention of non-smugglers. If the goalis to identify intestinal drug smug-glers, then the current method of iden-tification used by airport personnelseems to be effective and ultrasoundadds little.

References1. Meijer R, Bots ML (2003) Detection of

intestinal drug containers by ultrasoundscanning: an airport screening tool? Eur Radiol 13:1312–1315

2. Traub SJ, Hoffman RS, Nelson LS(2003) Body packing—the intemal concealment of illicit drugs. N Engl J Med 349:2519–2526

3. Hahn IH, Hoffman RS, Nelson LS(1999) Contrast CT fails to detect the last heroin packet (Abstract). J Toxicol Clin Toxicol 37:644–645

Eur Radiol (2005) 15:193DOI 10.1007/s00330-004-2468-0 L E T T E R T O T H E E D I T O R

Howard A. GrellerJohn McDonaghRobert S. HoffmanLewis S. Nelson

Use of ultrasound in the detection of intestinal drug smuggling

H. A. Greller (✉) · R. S. HoffmanL. S. NelsonNew York City Poison Control Center,New York, New York, USA

J. McDonaghDepartment of Emergency Medicine,SUNY at Stony Brook,Stony Brook, New York, USA