What is the effectiveness of the Mononucleosis (Mono) test?

From the Guidelines

The Mononucleosis (Mono) test is generally reliable but not perfect, with a sensitivity ranging from 70-95% and a specificity of 95-100%. This means that while a positive result is highly accurate, false negatives can occur, especially early in the infection or in certain populations such as young children 1.

Key Considerations

• The test typically detects heterophile antibodies produced in response to Epstein-Barr virus (EBV), the most common cause of mono.
• False negatives can occur in approximately 10% of patients, and are especially common in children younger than 10 years 1.
• The presence of VCA IgM (with or without VCA IgG) antibodies in the absence of antibodies to EBNA indicates recent primary infection with EBV 1.

Diagnostic Approach

• For best results, mono testing should be done when symptoms are present, and additional laboratory testing may be considered to differentiate EBV infection from a mononucleosis-like illness caused by other pathogens 1.
• Clinical symptoms and other lab tests (like white blood cell count) are also considered for a complete diagnosis.
• If symptoms persist but an initial test is negative, retesting after a week may be warranted, or more specific EBV antibody tests may be necessary for diagnosis 1.

From the Research

Effectiveness of the Mononucleosis (Mono) Test

The effectiveness of the Mononucleosis (Mono) test can be evaluated based on its ability to accurately diagnose the disease.

• The Mono test, also known as the monospot test, detects the presence of heterophile antibodies in the serum, which are indicative of Epstein-Barr virus (EBV) infection 2.
• However, the test may not be sensitive enough to detect the disease in its early stages, and false negatives can occur 3.
• The test has been compared to other diagnostic tests, such as the Paul-Bunnell (P-B) test and the Davidsohn modification of the Paul-Bunnell (P-B-D) test, and has been found to be equally accurate 4.
• The diagnostic accuracy of the Mono test can be measured using parameters such as sensitivity, specificity, positive predictive value, and negative predictive value 5, 6.
• These measures can provide information on the test's ability to discriminate between individuals with and without the disease, as well as its ability to predict the presence or absence of the disease.

Diagnostic Accuracy Measures

The diagnostic accuracy measures of the Mono test are important in evaluating its effectiveness.

• Sensitivity and specificity are measures of the test's ability to correctly identify individuals with and without the disease, respectively 5, 6.
• Positive and negative predictive values provide estimates of the probability of disease in individual patients, but these values vary according to disease prevalence 5, 6.
• The likelihood ratio is a measure of the test's ability to discriminate between individuals with and without the disease, and is considered a useful measure of diagnostic accuracy 5.
• The area under the receiver operating characteristic curve is a measure of the test's overall accuracy, and can provide information on the test's ability to distinguish between individuals with and without the disease 5.