Immunology USMLE Step 1 Practice Question
A 10-month-old boy with DiGeorge syndrome presents for routine health maintenance. Vital signs are normal (BP 95/60, HR 110, RR 28, Temp 37°C, SpO2 98% on room air). Laboratory studies show low CD3+ T cell count (800/μL). Chest X-ray reveals absent thymic shadow. He has not experienced recurrent infections to date and takes no medications. His mother asks whether he can safely receive all standard childhood vaccinations. Which vaccine is contraindicated because it contains live attenuated organisms?
Answer choices
- ARotavirus vaccineCorrect answer
- BTetanus toxoid
- CInactivated poliovirus vaccine
- DHaemophilus influenzae type b polysaccharide conjugate vaccine
- EPneumococcal conjugate vaccine
- FHepatitis B vaccine
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