The leukocyte response and the erythrocyte sedimentation rate after Diphtheria - Tetanus - Pertussis vaccination in children

The leukocyte response and erythrocyte sedimentation rate (ESR) were studied in 53 healthy infants, who were routinely immunized with Diphtheria-Tetanus-Pertussis (DTP) vaccine. The leukocyte response was determined in 28 infants aged 2-12 months before and 24 hours after vaccination. In a subgroup of 12 infants it was determined also after 72 hours. The total leukocyte count (per mm³) increased from 11.028 ± 615 (mean ± SEM) before vaccination to 13.988 ± 540 following vaccination (p < 0.001). The total neutrophil count increased from 3.878 + 444 to 7.411 ± 400 (p < 0.001) and the total band count from 80 ± 31 to 718 ± 167 (p < 0.001). Both returned to prevaccination levels after 72 hours. The ESR was studied in 25 infants aged 2-12 months. Blood fibrinogen and globulin levels were also determined in 10 infants. ESR was elevated following vaccination with mean increase from 15 ± 3 mm/h before vaccination to 33 ± 4 post vaccination (P < 0.001). The ESR continued to increase with a maximal rate being observed 72 hours post vaccination and thereafter it began to decrease. However, after 96 hours it was still elevated. Blood fibrinogen showed a significant increase from 342 ± 31 mg/dl before vaccination to 436 ± 40 post vaccination (p < 0.002), while serum globulin levels did not show any significant change. In five infants who received only DT vaccination no change was observed in the leukocyte count and ESR. It is concluded that elevated leukocyte count with a 'shift to the left' and elevated ESR can occur following DTP vaccination and not necessarily represent an infectious process.