Lymphatic and immune system
Review the following Case
Rebecca Jones is a typical second grader at Orchard Hills school. Rebecca is usually a happy child, but has not been feeling well for the past day or so and has been experiencing a fever, headache, and severe throat pain when swallowing.
Rebecca’s mom took her to the doctor who examined her and found the following:
1. Tonsils red, swollen and containing white exudate.
2. Fever of 101 deg F.
3. Bilateral cervical lymphadenopathy
4. CBC indicated leukocytosis and neutrophilia.
The doctor diagnosed Rebecca with acute bacterial pharyngitis and prescribed a course of antibiotics.
After a few days, Rebecca began to feel better and made a full recovery.
Discuss the case by addressing the following:
1. The pediatrician described Rebecca’s pharynx, uvula, and tonsils as swollen and red. Describe how the immune system triggers inflammation.
2. The exudate on Rebecca’s tonsils consisted primarily of neutrophils. Describe the role of neutrophils in helping to overcome a bacterial infection.
3. Describe the role of the lymph nodes and other lymphatic organs in overcoming a bacterial infection.
4. Describe how fever is produced and how fever can help to overcome a bacterial infection.
Sample Solution
Lymphatic and immune system
The immune system protects the body from possibly harmful substances by recognizing and responding to antigens. The inflammatory response (inflammation) occurs when tissues are injured by bacteria, trauma, toxins, heat, or any other cause. The damaged cells release chemicals including histamine, bradykinin, and prostaglandins. These chemicals cause blood vessels to leak fluid into the tissues, causing swelling. This helps isolate the foreign substance from further contact with body tissues. Neutrophils have a well-established role during fungal and extracellular bacterial infections where they promote bacterial clearance through phagocytosis, production of reactive oxygen and nitrogen species (ROS/RNS), neutrophil extracellular trap (NET) formation, and production of pro-inflammatory cytokines.
