Immunoglobulin replacement and antimicrobial prophylaxis — branching viva

Outpatient clinic: a six-year-old boy with X-linked agammaglobulinaemia is established on intravenous immunoglobulin every four weeks. He has had three breakthrough pneumonias this year despite a trough IgG in the lower half of the normal range, and his family lives two hours from the hospital. The examiner asks: what is your framework, what are the reassessment questions before changing the dose, what are the advantages of switching to subcutaneous immunoglobulin, and what role does antimicrobial prophylaxis play — then branches to a child with specific antibody deficiency and asks you to justify why you would NOT start immunoglobulin first.