system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
One week after starting amoxicillin for sinusitis, a 4-year-old girl is brought to the emergency department with fever, rash, and myalgia. She has been hospitalized multiple times for recurrent streptococcal pneumonia and meningitis. She appears tired. Examination shows a diffuse urticarial rash. Her antibiotic is discontinued. Which of the following is the most likely underlying mechanism for her recurrent infections?
assistant
Impaired opsonization