A nurse is providing care for clients in a hospital setting. Which of the following clients is at highest risk for developing an opportunistic infection?

A. A client who has a risk of severe anaphylaxis: Anaphylaxis is an overactive immune response (hypersensitivity), not an immunodeficiency that leads to opportunistic infections. B. A client who has advanced osteoarthritis: Osteoarthritis is a degenerative "wear-and-tear" joint disease, not a systemic immune disorder. C. A client who is experiencing a rheumatoid arthritis flare up: While the treatments for RA (immunosuppressants) increase risk, the disease itself is autoimmune; it does not deplete the immune system as severely as HIV. D. A client who has HIV: HIV specifically attacks CD4+ T-cells, the "conductors" of the immune system. When these levels drop, the body becomes susceptible to opportunistic infections (pathogens that usually don't cause disease in healthy people).