A nurse is reviewing the laboratory results of a client who has a pressure ulcer. The nurse should identify an elevation in which of the following laboratory values as an indication that the client has developed an infection?

A. BUN: Blood urea nitrogen reflects kidney function and hydration status, not infection. Elevated BUN levels are usually associated with dehydration or renal impairment rather than a pressure ulcer infection. B. WBC count: An elevated white blood cell count indicates the body’s immune response to infection. In the context of a pressure ulcer, an increase suggests the presence of local or systemic infection that requires intervention. C. RBC count: Red blood cell levels reflect oxygen-carrying capacity and are related to anemia or blood loss. An elevated or decreased RBC count does not directly indicate infection. D. Potassium: Potassium levels are associated with electrolyte balance and cardiac or neuromuscular function. Changes in potassium do not provide direct evidence of infection in a client with a pressure ulcer.