UCSF Navigation Bar

UCSF Departments of Pathology & Laboratory Medicine Home Page

Lab Manual for UCSF Clinical Laboratories

Lab Manual for SFGH

Internal Resources


Item Value
Available Stat? No
Test code MONO
Performed by? Microbiology
Sendout? no
Price range $$
In House Availability Monday - Sat
Principle This procedure is based on agglutination of horse red blood cells by the heterophile antibody associated with infectious mononucleosis (IM). Since horse red blood cells contain both Forssman and IM antigens, a differential absorption of the patient's serum is necessary to remove the Forssman type antibody. This is accomplished by absorbing the serum with a guinea pig kidney preparation which contains the Forssman antigen. IM antibodies are not removed by this absorption. Agglutination of horse red blood cells by the absorbed patient specimen is indicative of a positive reaction for the IM heterophile antibody.
Interpretation This test is useful to distinguish infectious mononucleosis caused by the Epstein-Barr Virus from other agents which can cause an IM-like syndrome, such as cytomegalovirus, adenovirus, hepatitis viruses and Toxoplasma gondii, but which have a negative mono test. Concomitant infections with a number of these agents have been reported after onset of symptomatic disease. It may take 1-3 weeks for IM antibody to be detectable. Children with mononucleosis under five years of age are more likely to give negative test results than adults. Since titer has no relationship of severity of disease or prognosis, this test is reported as positive or negative.
Container type gold top gel tube
Amount to Collect 3 mL
Sample type Blood
Normal range negative
Synonyms Infectious Mononucleosis; Mono Test; EBV
Stability 3 days at 4°C.
References Mandell GL, Bennett JE, and Dolin R, Eds. Principles and Practice of Infectious Diseases, 6th Ed. Churchill Livingston, Inc., NY, 2005.
CPT coding 86308
Last Updated 2/3/2009 11:30:42 AM
Search Our Test Menu
UCSF home page UCSF home page About UCSF Search UCSF UCSF Medical Center