A 20-year-old male with a recent diagnosis of infectious mononucleosis presented to the ED with complaints of lightheadedness. He reported that when he woke up in the morning and got out of bed, he felt as though he might faint. He also noted that he had some left sided upper abdominal pain and left shoulder pain. He denied trauma. He reported that throughout the day he began to feel generally worse, and the abdominal pain had increased.


Initial VS: BP 136/82, HR 86, RR 18, SpO2 99% on RA


Physical exam revealed a young male who appeared uncomfortable. His abdomen was distended, and there was diffuse tenderness to palpation.


Given the history and clinical presentation, although uncommon, spontaneous rupture of the spleen was high on the differential. Within minutes of being seen, a FAST exam was done.


Here is the LUQ:



In all of these clips, you can see the spleen. Sitting on top of the spleen is tissue that is hyperechoic compared to the spleen. This was interpreted as a subcapsular hematoma. You can also see some anechoic fluid sitting directly under the diaphragm. This was interpreted as free fluid in the abdomen likely representing rupture of the capsule.


Screen Shot 2015-07-24 at 9.27.48 AM


A view of the RUQ was obtained:

There was no free fluid appreciated in this view.


Lastly, a view of the pelvis was obtained:


You can see in these clips that there is free fluid in the retrovesicular pouch.


Labs and a CT scan were obtained as this patient was hemodynamically stable.


His hemoglobin returned at 14.3. Images from the CT scan can be seen below:

Screen Shot 2015-07-23 at 1.06.36 PM


Screen Shot 2015-07-23 at 1.06.00 PM

A subcapsular splenic hematoma was seen along with free fluid in the pelvis. There was no evidence of active extravasation.


Spontaneous Rupture of the Spleen in Mononucleosis:

  • Spontaneous rupture of the spleen in the setting of mononucleosis is a rare event, occurring in just 0.1-0.5% of those with mononucleosis.
  • This condition can carry significant morbidity and mortality, and there have been case reports of lethal atraumatic rupture of the spleen.
  • Typical presentation is fever, pharyngitis, and lymphadenopathy 1-3 weeks prior to onset of abdominal pain and signs of hypovolemia.
  • Kher sign (referred pain to the left shoulder) may be present in up to 50% of patients.
  • Traditionally management was splenectomy, however, now more surgeons are opting for conservative management with either watchful waiting or splenic artery embolization.
  • In the setting of hemodynamic instability, total splenectomy still seems to be the preferred management.


Surgery was consulted, and he was admitted to their service with plans for non-operative management and serial hemoglobin checks. His hemoglobin remained stable, and he was discharged on hospital day 3 in improved condition.




  1. Brichkov I, Cummings L, Fazylov R, Horovitz JH. Nonoperative management of spontaneous splenic rupture in infectious mononucleosis: the role for emerging diagnostic and treatment modalities. Am Surg. 2006;72(5):401-404.
  2. Khoo SG, Ullah I, Manning KP, Fenton JE. Spontaneous splenic rupture in infectious mononucleosis. Ear Nose Throat J. 2007;86(5):300-301.
  3. Pfaffli M, Wyler D. [Lethal atraumatic splenic rupture due to infectious mononucleosis]. Arch Kriminol. 2010;225(5-6):195-200.
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