What is a common laboratory finding in a patient with chronic granulomatous disease?

In chronic granulomatous disease (CGD), a key laboratory finding is the increased leukocyte count. This condition is characterized by a defect in the NADPH oxidase complex, leading to an inability of phagocytes to generate reactive oxygen species necessary for killing certain types of bacteria and fungi. As a result, patients with CGD often experience recurrent infections, particularly from catalase-positive organisms.

The body responds to these recurrent infections by increasing the production of white blood cells, hence the elevated leukocyte counts seen in laboratory tests. This reflects the immune system's attempt to combat the frequent bacterial and fungal infections that patients with CGD are prone to.

Other options like increased serum bilirubin levels and impaired opsonization are not typical findings in CGD. Additionally, normal respiratory burst would contradict the very nature of CGD, which is defined by impaired respiratory burst activity due to the defective oxidative burst in phagocytes. Thus, the hallmark laboratory finding in CGD is indeed the elevated leukocyte count as the body tries to cope with heightened infection risk.