Diagnostic Considerations
EBV-negative Mononucleosis
Approximately 10 percent of mononucleosis-type cases are not caused by EBV. CMV, HIV, Toxoplasma, human herpesvirus type 6 (HHV-6), hepatitis B and HHV-7 present similarly to EBV induced IM and should be considered in a heterophile-negative mononucleosis-like syndrome.
Table 1. Differential Diagnoses of Infectious Mononucleosis (Open Table in a new window)
Clinical Parameters |
Epstein-Barr Virus |
Cyto-megalovirus |
Toxoplasmosis |
Viral Hepatitis |
|
Symptoms |
Fatigue |
+++ |
+ |
+/- |
+ |
Malaise |
++ |
+ |
- |
+ |
|
Mild sore throat |
+ |
+ |
+/- |
+/- |
|
Early maculopapular rash |
± |
- |
- |
+/- |
|
Signs |
Early bilateral upper eyelid edema |
± |
- |
- |
- |
Unilateral localized adenopathy |
- |
- |
+ |
- |
|
Bilateral posterior cervical adenopathy |
+ |
+ |
- |
+/- |
|
Tender hepatomegaly |
+/- |
+/- |
- |
+ |
|
Splenomegaly |
+ |
+/- |
+/- |
- |
|
Laboratory abnormalities |
WBC count |
N*/- |
N/- |
N |
¯ |
Elevated SGOT†/SGPT‡ |
++ |
+ |
+/- |
+++ |
|
Atypical lymphocytes (≥ 10%) |
+ |
+ |
- |
- |
|
Thrombocytopenia |
+/- |
+/- |
- |
+/- |
|
Elevated IgM§ CMV titer |
- |
+ |
- |
- |
|
Elevated IgM EBV VCAII titer |
+ |
- |
- |
- |
|
Elevated IgM toxoplasmosis titer |
- |
- |
+ |
- |
|
Positive hepatitis (eg, A, B, D) test |
- |
- |
- |
+ |
|
*Normal † Serum glutamic-oxaloacetic transaminase ‡ Serum glutamic-pyruvic transaminase § Immunoglobulin M II Viral capsid antigen |