From the Guidelines
Ultrasound is not routinely needed for patients with infectious mononucleosis (mono) who have abdominal pain, unless there are specific concerns about complications, such as severe left upper quadrant or left-sided abdominal pain, suspicion of splenic rupture, or significantly elevated liver function tests. In most cases of mono with abdominal pain, the discomfort is typically due to splenomegaly (enlarged spleen) or hepatitis, which can be clinically assessed without imaging 1. The American College of Radiology (ACR) Appropriateness Criteria for acute nonlocalized abdominal pain highlights the importance of imaging in evaluating patients with abdominal pain, but also notes that the choice of imaging modality depends on the clinical presentation and suspected diagnosis 1.
Key Considerations
- The ACR Appropriateness Criteria suggests that imaging plays an essential role in narrowing the differential diagnosis and directing management in patients with abdominal pain, but does not specifically recommend ultrasound as the first-line imaging modality for patients with mono and abdominal pain 1.
- Patients with mono should be advised to avoid contact sports and strenuous physical activity for at least 3-4 weeks after diagnosis to reduce the risk of splenic rupture, regardless of whether an ultrasound is performed.
- If the physical examination reveals significant tenderness in the left upper quadrant or if the patient experiences sudden, severe abdominal pain, immediate medical attention with ultrasound imaging is warranted to rule out the rare but serious complication of splenic rupture.
Clinical Assessment
In most cases, a thorough clinical assessment, including a physical examination and laboratory tests, can help identify the cause of abdominal pain in patients with mono. However, if there are concerns about complications, such as splenic rupture or significantly elevated liver function tests, an ultrasound should be considered to evaluate the size of the spleen and liver, detect any splenic complications, and rule out other causes of abdominal pain 1.
From the Research
Mono with Abdominal Pain
- Abdominal pain is a common symptom in patients with infectious mononucleosis, and it can be a sign of a serious complication such as splenic rupture 2, 3, 4.
- The risk of splenic rupture is higher in men under 30 years old, especially within 4 weeks of symptom onset 2.
- Ultrasound (USS) is recommended to confirm the diagnosis of splenomegaly and to assess the risk of splenic rupture 2, 5.
- Patients with infectious mononucleosis should be advised to avoid vigorous physical activity for at least 4-6 weeks, and USS should be performed before returning to high-risk activities 2.
- Abdominal ultrasonography is a useful diagnostic tool in patients with abdominal pain and suspected splenic infarction or rupture, but it may have low sensitivity in some cases 4.
Diagnostic Approach
- Physical examination and laboratory tests are essential in evaluating patients with abdominal pain and suspected infectious mononucleosis 5, 3.
- Imaging studies such as CT scan, ultrasound, or radionuclide scan may be used to confirm the diagnosis of splenic rupture or infarction 3, 4.
- Selective splenic angiography is an accurate diagnostic tool, but it is invasive and rarely used 3.
Management
- Treatment of splenic rupture or infarction usually involves splenectomy, but non-operative therapy may be considered in stable patients 2, 3.
- Patients with splenomegaly should be advised to avoid contact sports and other activities that may increase the risk of splenic rupture 5.
- Management of infectious mononucleosis involves treating the underlying disease process, and patients with limited splenic function may require increased vaccination and prophylactic antibiotics 5.