What laboratory finding is generally expected when there is an infection?

The expected laboratory finding in the presence of an infection is an increased white blood cell count. This reaction is part of the body's immune response to fight off pathogens such as bacteria, viruses, or fungi. White blood cells, or leukocytes, play a crucial role in the immune defense by identifying and eliminating these foreign invaders.

During an infection, the bone marrow produces and releases more white blood cells to increase the body's ability to respond to the infectious agent. The types of white blood cells that may increase include neutrophils during bacterial infections and lymphocytes during viral infections, among others. A significant elevation in white blood cells would often indicate an ongoing infection or inflammatory response.

Other laboratory findings associated with infections may include changes in the type of white blood cells and elevated levels of inflammatory markers, but the most straightforward and significant change is the increase in overall white blood cell count, making it a key indicator of infection in laboratory assessments.