An 84-year-old patient is hospitalized for an infected stasis ulcer on his ankle. The nurse is aware that this patient is at risk for a hospital-acquired infection (HAI) because the:

Choice A rationale

Stasis ulcers do not specifically predispose older adults to pneumonia and urinary infections. These infections have different primary risk factors and are not directly related to the presence of stasis ulcers.

Choice B rationale

The patient's defenses are already engaged with the initial infection, which can weaken the immune response and make the body more susceptible to additional infections, such as hospital-acquired infections (HAIs).

Choice C rationale

While being bedfast can increase the risk of pressure sores and related infections, it is not directly caused by the presence of a stasis ulcer. The patient's mobility status and overall health condition are more relevant factors.

Choice D rationale

The patient does not have a blood-borne infection. The presence of a stasis ulcer indicates a local infection, not a systemic blood-borne infection.

Choice A rationale

Interferons are proteins produced by cells in response to viral infections and are part of the body's immune response, but they are not directly involved in the engulfing of pathogens.

Choice B rationale

Phagocytosis is the process by which certain cells, such as macrophages and neutrophils, engulf and destroy pathogens. This is a crucial mechanism of the innate immune system.

Choice C rationale

Creating antibodies is the function of B cells in the adaptive immune system, which works alongside phagocytosis but is not the same process.

Choice D rationale

Phagocytosis itself does not stimulate the body to make more white blood cells, but it is a function performed by existing white blood cells to eliminate pathogens.