A nurse is caring for a client who has HIV. Which of the following laboratory values is the nurse's priority?

The correct answer is A: CD4-T-cell count 180 cells/mm3. This is the nurse's priority because it directly reflects the client's immune status and helps guide treatment decisions in HIV management. A low CD4 count indicates immunosuppression and increased risk of opportunistic infections. Choices B, C, and D are important in HIV care but do not directly indicate the severity of the client's condition like the CD4 count does. A positive Western blot test confirms HIV infection but does not provide immediate information on the client's immune status. Platelets and WBC are important for assessing overall health but do not specifically reflect the impact of HIV on the immune system.