University:
College
Course:
Medical Laboratory Science
Academic year:

2023
Views:

121

Pages:

1
Author:

Carlo M.

IMMUNOLOGY AND SEROLOGY LABORATORY SEROLOGIC TESTS FOR HETEROPHILE ANTIBODIES AGGLUTININS FOR SHEEP ERYHTROCYTES IN HUMAN SERUM Type of Serum OUTLINE • Infectious Mononucleosis o Discussion o IM Test Procedures • INFECTIOUS MONONUCLEOSIS DISCUSSION • • • • Heterophile antibodies (HA) refer to antibodies with affinity for related or identical antigen found in sheep cells, guinea pig tissues and other unrelated biological substances. Three types of heterophile antibodies are recognized by absorption reaction o Forssman o Serum Sickness o Infectious mononucleosis Infectious mononucleosis is an acute self-limiting disease caused by Epstein Barr virus typically seen in young adults. It is characterized by fever, sore throat, cervical lymphadenopathy, splenomegaly and mild hepatitis. IM Quick test is a serological test for infectious mononucleosis and it is based on the principle that horse red blood cells coated with latex particles (IM) are agglutinated by heterophile antibodies of IM. IM TEST PROCEDURES PROCEDURE • • • • Bring reagents and sera to room temperature and mix erythrocyte reagent gently before use. Place in separate cells of the slide. o Serum 1 drop o Positive Control (red dropper) 1 drop o Negative Control (green dropper) 1 drop o Erythrocyte reagent (white dropper) 1 drop each Mix with separate sticks and spread the fluid over the entire area of each cell. Tilt the slide back and forth slowly for 2 minutes. RESULTS • • Positive result - distinct agglutination (indicates the presence of IM) Negative result - absence of agglutination (indicates the absence of IM) CLASSICAL LABORATORY FINDINGS IN ACUTE IM • • • • • Heterophile antibody test - positive Anti-VCA IgM - elevated titer Liver enzymes - elevated Leukocyte differential - increased number of variant (atypical) lymphocytes Note: VCA - viral capsid antigen Normal Infectious Mononucleosis Serum sickness • Absorbed by Guinea Pig Positive (+) Negative (-) Absorbed by Beef Erythrocytes Negative (-) Positive (+) Positive (+) Positive (+)