Skip to main content
Ch. 22 The Lymphatic System and Immunity
Martini - Fundamentals of Anatomy & Physiology 11th Edition
Martini, Nath, Bartholomew11th EditionFundamentals of Anatomy & PhysiologyISBN: 9780136874089Not the one you use?Change textbook
Chapter 22, Problem 26

Ted finds out that he has been exposed to measles. He is concerned that he might have contracted the disease, so he goes to see his physician. The physician takes a blood sample and sends it to a lab for antibody levels and titers. The results show an elevated level and activity of IgM antibodies to rubella (measles) virus but very few IgG antibodies to the virus. Has Ted contracted the disease?

Verified step by step guidance
1
Step 1: Understand the roles of IgM and IgG antibodies in immune response. IgM antibodies are the first type produced by the immune system when a new infection occurs, indicating recent or current infection. IgG antibodies develop later and indicate past exposure or immunity.
Step 2: Analyze the lab results: elevated IgM antibodies to the measles virus suggest that Ted's immune system is currently responding to a recent infection, while very few IgG antibodies indicate that he has not yet developed long-term immunity.
Step 3: Recognize that the presence of high IgM and low IgG typically means an acute or recent infection rather than past immunity or vaccination.
Step 4: Conclude that based on the antibody profile, Ted has likely contracted the measles virus recently, as his immune system is actively producing IgM antibodies but has not yet produced significant IgG antibodies.
Step 5: Understand that further clinical evaluation and monitoring of symptoms are important to confirm the diagnosis and manage the disease appropriately.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

IgM and IgG Antibodies

IgM antibodies are the first type produced by the immune system in response to a new infection, indicating recent or current exposure. IgG antibodies develop later and provide long-term immunity, showing past infection or vaccination. The presence of high IgM and low IgG suggests an early or acute phase of infection.
Recommended video:

Serological Testing and Antibody Titers

Serological tests measure antibody levels in the blood to determine immune response to pathogens. Antibody titers quantify the concentration of specific antibodies, helping to distinguish between recent infection, past exposure, or immunity. Elevated IgM titers typically indicate recent infection.
Recommended video:
0:48
Antibodies

Clinical Interpretation of Antibody Results in Measles

In measles diagnosis, elevated IgM antibodies with low IgG suggest recent infection, as IgM appears early and IgG develops later. However, cross-reactivity or false positives can occur, so clinical symptoms and exposure history must be considered to confirm if the disease is contracted.
Recommended video:
2:34
Antibody Diversity
Related Practice
Textbook Question

An investigator at a crime scene discovers some body fluid on the victim's clothing. The investigator carefully takes a sample and sends it to the crime lab for analysis. On the basis of the analysis of antibodies, could the crime lab determine whether the sample is blood plasma or semen? Explain.

1136
views
Textbook Question

An anesthesia technician is advised that she should be vaccinated against hepatitis B, which is caused by a virus. She is given one injection and is told to come back for a second injection in a month and a third injection after 6 months. Why is this series of injections necessary?

1014
views
Textbook Question

Give one example of each type of immunity: innate immunity, naturally acquired active immunity, artificially acquired active immunity, artificially acquired passive immunity, and naturally acquired passive immunity.

1478
views
Textbook Question

Paula's grandfather is diagnosed as having lung cancer. His physician takes biopsies of several lymph nodes from neighboring regions of the body, and Paula wonders why, since his cancer is in the lungs. What would you tell her?

717
views
Textbook Question

While walking along the street, you and your friend see an elderly woman whose left arm appears to be swollen to several times its normal size. Your friend wonders aloud what might be its cause. You say that it may be likely that the woman had a radical mastectomy (the removal of a breast because of cancer). Explain the rationale behind your answer.

49
views
Textbook Question

Willy is allergic to ragweed pollen and tells you that he read about a medication that can help his condition by blocking certain antibodies. Do you think that this treatment could help Willy? Explain.

41
views