Reactivation of the bacille Calmette-Guérin scar following immune reconstitution during treatment of infant acute lymphoblastic leukemia.

The authors describe an infant presenting at 2 weeks of age with congenital acute lymphoblastic leukemia who had previously received routine bacille Calmette-Guérin (BCG) vaccination at birth. The risk of BCG dissemination in immunocompromised infants is discussed and the use of antimycobacterial prophylaxis in such cases considered.