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What is Paul Bunnell test is for and explain in detail?
Laboratory diagnosis of IMN
1. Heterophile antibodies test

 The standard diagnostic procedure in children and young adults is heterophile antibodies test - Paul – Bunnell Test
 A titre of 40 fold or greater is diagnostic of acute EBV infection in a patient who has symptoms compatible with infectious mononucleosis,
 The test usually remains positive for 3 months.
 The test is usually negative in children < 5 years, in elderly or in patients with symptoms not typical of infectious mononucleosis.
 Monospot test for heterophile antibodies is more sensitive than the classical heterophile test.

2. EBV specific antibody test

 Used in patients who lack heterophile antibodies (children < 5 years) and for patients with atypical presentation.

anti-viral capsid antigen (anti-VCA)→most common anti-EBV nuclear antigen (anti-EBNA) anti - early antigen (anti - EA)