IM

Q: Why is Infectious mononucleosis (IM) called Infectious mononucleosis (IM)?

Answer: 

This question aims to teach the habit of understanding nomenclatures in medicine and science. The pathophysiology can be understood well if the nomenclature is understood well.

Infectious mononucleosis (IM) is characterized by absolute lymphocytosis and atypical mononuclear cells in the blood. In fact, the name of the disease was changed 30 years after its discovery from "Drüsenfieber" (glandular fever) to "infectious mononucleosis."

Infectious mononucleosis (IM) is marked by a triad of 

• fever
• tonsillar pharyngitis, and 
• lymphadenopathy  

The underlying cause is Epstein-Barr virus (EBV).

#ID

References:

1. Sprunt TP, Evans FA. Mononucleosis leukocytosis in reaction to acute infections (infectious mononucleosis). Bull Johns Hopkins Hosp 1920; 31:409.

2. Evans AS. The history of infectious mononucleosis. Am J Med Sci 1974; 267:189.

3. Dunmire SK, Hogquist KA, Balfour HH. Infectious Mononucleosis. Curr Top Microbiol Immunol 2015; 390:211.