Understanding Lab Tests for Infectious Mononucleosis
Written by Private MD Labs Medical Writing Team • Last Updated: September 8, 2025
Infectious mononucleosis, commonly known as mono or the "kissing disease," is a viral infection typically caused by the Epstein-Barr virus (EBV). While the primary diagnosis is often made through specific mono tests and clinical evaluation, additional blood tests play important roles in monitoring the body's response to infection and ruling out other conditions.
Top Recommended Test
Lactic Acid Dehydrogenase (LD) (LDH)
This test measures LDH levels in the blood, which can become elevated during infectious mononucleosis due to cellular breakdown that occurs as the immune system fights the viral infection. Monitoring LDH levels helps assess the extent of tissue involvement and track recovery progress.
2907 reviews
The Role of Blood Testing in Mono
Blood tests for infectious mononucleosis serve multiple purposes: they help confirm the diagnosis through specific mono tests, monitor organ function and cellular damage during the infection, and distinguish mono from other conditions with similar symptoms. These supporting tests provide valuable information about how the infection is affecting your body.
Other Relevant Tests
Rheumatoid Factor (RA)
While this test is primarily used to diagnose rheumatoid arthritis, infectious mononucleosis can sometimes cause a false-positive result for rheumatoid factor. Testing RF helps healthcare providers distinguish between mono and autoimmune conditions when symptoms overlap, ensuring accurate diagnosis and appropriate treatment.
2907 reviews
Understanding Your Results
Elevated LDH levels during mono indicate active cellular damage from the viral infection, which is a normal part of the disease process. A positive rheumatoid factor in the context of mono symptoms typically represents a temporary immune system response rather than true rheumatoid arthritis. Your healthcare provider will interpret these results alongside other clinical findings and specific mono tests.
Important Considerations
The information here is for educational purposes only and is not a substitute for professional medical advice. Always consult with a healthcare provider for diagnosis and treatment.
