Final answer:
An elevated white blood cell count indicates an infection, as the body increases white blood cell production in response to pathogens. This is verified by a full blood count test and is a form of positive feedback in the body's immune response.
Step-by-step explanation:
When assessing a patient for signs of an infection, the laboratory result indicative of an infection is c. Elevated white blood cell count. This increase, known as neutrophilia, suggests that the body is responding to an infection by deploying more white blood cells to combat it. A full blood count test can reveal this condition, which is characterized by a raised number of white cells compared to "normal" values. This elevation is a form of positive feedback, where more white blood cells are recruited in response to increasing numbers of pathogens.
Critical thinking questions such as what is suggested by the presence of white blood cells in the urine would indicate that an infection may be present in the urinary tract. Analysis of differential cell counts in the blood can provide additional information regarding disease conditions associated with deviations in specific white blood cell types.