A patient tells the nurse that he is 65 years old and has not had a cold or any other type of infection for at least 30 years. Which assumption can the nurse make about this patient's immune system?

Question

1. The patient's lymph nodes must be engorged with bacteria.
2. The patient must have intact and functioning MHC receptors.
3. The patient has rapidly proliferating white blood cells.
4. The patient's spleen is probably enlarged.

Answer 1

2
Rationale 1: Lymph nodes would be engorged if an infection or inflammatory process were occurring somewhere in the body.
Rationale 2: Major histocompatiblity complex (MHC) receptors on cells are one type of marker used by the immune system to determine whether a cell belongs to the organism. Because the patient claims he has not had a cold or other inflammatory response for at least 30 years, the nurse can surmise that his MHC receptors are functioning well.
Rationale 3: Rapidly proliferating white blood cells would not necessarily provide increased immune protection. If WBCs are immature, they do not work effectively against pathogens.
Rationale 4: It would be more likely that an enlarged spleen would indicate infection or inflammation somewhere in the body.