A polyclonal proliferation of T-cells, almost always due to infection. The absolute lymphocyte count is in excess of 4x109 / L
Lymphocyte Populations in the Blood
T-cells (CD3+) is around 75%
B-cells (CD20+) is around 15%
NK-cells (CD56+) is around 5%
Relative Proportion of T-Cell Subtypes
Helper T-cells (CD4+) is around 70%
Cytotoxic T-cells (CD8+) is around 30%
Reactive Lymphocytosis Presentation
Classic presentation is symptoms similar to that of mono.
- Fever, chills, night sweats
- Cough (non-productive)
- Headache and muscle aches
- General malaise and loss of appetite
Reactive Lymphocytosis on PE
The patient may have...
- Lymphadenopathy (tender)
- Hepatomegaly / splenomegaly
DDx of Reactive Lymphocytosis
Pertussis (whooping cough)
Also could be drug-related, stress, or post-splenectomy.
Tender lymph nodes
Fatigue (often long duration)
May have palpable splenomegaly
May have hepatitis
Typical age is the teens/early 20's
Reactive Lymphocytosis and Neoplasism
You must rule out a neoplastic cause.
This can often be done by gathering a thorough history, performing an in-depth physical exam, and potentially ordering labwork.
Lengthy respiratory infection around 6 weeks
Gram negative bacillus
Rhinorrhea, congestion, sneezing, and a hacking cough
Normal, small-appearing lymphocytes on PBS
Congenital rubella is the most feared complication where virtually all organs are involved, along with permanent motor damage and mental retardation.
Lymphadenopathy, maculopapular rash, and fever.
Can culture the virus and detect antibodies.