An 18-month-old boy is evaluated for recurrent infections. He has been hospitalized 3 times with pneumonia since age 3 months. He has also had multiple skin infections requiring treatment with antibacterial and antifungal agents. During his last episode of pneumonia, he developed a large pleural effusion, which was drained. The pleural fluid revealed numerous neutrophils containing a large number of intact gram-positive cocci. The microorganisms responsible for this patient's recurrent infections most likely produce which of the following virulence factors?

Question

An 18-month-old boy is evaluated for recurrent infections.  He has been hospitalized 3 times with pneumonia since age 3 months.  He has also had multiple skin infections requiring treatment with antibacterial and antifungal agents.  During his last episode of pneumonia, he developed a large pleural effusion, which was drained.  The pleural fluid revealed numerous neutrophils containing a large number of intact gram-positive cocci.  The microorganisms responsible for this patient's recurrent infections most likely produce which of the following virulence factors?

Quizplus · Accepted Answer

Eductional Objective: Chronic granulomatous disease is a primary immunodeficiency due to impaired NADPH oxidase, an enzyme that generates reactive oxygen species in phagolysosomes.  Diminished intracellular killing within neutrophils leads to susceptibility to recurrent infection with catalase-producing bacteria (eg, Staphylococcus aureus, Nocardia) and fungi (eg, Aspergillus).

An 18-Month-Old Boy Is Evaluated for Recurrent Infections