Penicillin prophylaxis in children with cardiac disease: postextraction bacteremia and penicillin-resistant strains of viridans streptococci.

The incidence of postextraction bacteremia in 82 children with dental foci and cardiac disease given parenteral penicillin prophylaxis was assessed 5 min after extraction. Penicillin concentrations were determined in blood samples obtained at the same time. Before extraction, cultures were taken from the gingival sulcus. Postextraction bacteremia occurred in 21% of the patients and was due to penicillin-sensitive microorganisms in 10 and to both penicillin-sensitive and penicillin-resistant microorganisms in seven children. In three of these children penicillin-resistant viridans streptococcal strains were isolated. Penicillin-resistant viridans streptococci were present in the gingival sulcus flora of 39% of the children, but a relationship between the presence of such strains in the gingival sulcus and the occurrence of postextraction bacteremia could not be demonstrated. There was no difference in the serum penicillin concentrations found in children with bacteremia due to penicillin-sensitive or penicillin-resistant microorganisms, or between the concentrations in children with and without bacteremia.