A 3-year-old boy has recurrent sinopulmonary infections starting at 6 months of age. Serum immunoglobulin levels are: IgG 80 mg/dL (normal 600–1600), IgA undetectable, IgM undetectable. Flow cytometry shows absence of CD19+ B cells. Bruton's tyrosine kinase (BTK) gene sequencing reveals a nonsense mutation. Which immunization should be specifically AVOIDED in this child?
- A Inactivated influenza vaccine
- B Pneumococcal conjugate vaccine
- C Live attenuated oral polio vaccine (OPV) ✓
- D Tetanus toxoid vaccine
Explanation
This is X-linked agammaglobulinemia (XLA/Bruton's disease). Patients lack mature B cells and cannot produce antibodies. Live attenuated OPV is absolutely contraindicated because the attenuated poliovirus can revert to virulence and cause vaccine-associated paralytic poliomyelitis (VAPP) in immunocompromised patients — XLA patients have developed chronic CNS enterovirus infections from OPV. Inactivated influenza, pneumococcal conjugate, and tetanus toxoid are inactivated/subunit/toxoid vaccines and are safe (though efficacy is limited without B cells). IGIV replacement therapy provides passive IgG protection.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.