POCUS for the Kissing Disease

That’s right! You can use POCUS in the workup of the patient with suspected infectious mononucleosis. So say Drs. Sarah Farukhi and JC Fox from UC Irvine. They published their case report in the latest issue of CUJO, the Critical Ultrasound Journal. These are cases that we see all the time. Mid-late teens. Exudative pharyngitis. It could be strep. It could be mono. All sorts of issues with the accuracy of diagnosis in these patients, including the failings of the Monospot early in the course of mono. We won’t review all of that here. But if you have such a patient, think about putting the probe on to look for an enlarged spleen. Put the probe on in the longitudinal plane in the LUQ just as you would for Abdominal EDE (aka The FAST Scan). Find the spleen at its largest, even rotating the probe a few degrees as needed. Measure the spleen and its largest diameter. If your result is over 12 cm, then the spleen is large. Barring another diagnosis in your differential, you have your diagnosis. It’s mono. See the illustration from the book which I’ve adapted to show where one should perform the measurement.

Steve