Relationship between the magnitude of bacteremia in children and the clinical disease.

The relationship between the magnitude of bacteremia due to Haemophilus influenzae, Streptococcus pneumoniae, and Neisseria meningitidis and the clinical diagnosis was determined on 79 children who were not receiving prior antibiotic therapy and had fever, either in the presence or absence of focal signs of infection. Bacteremia was quantitated by the recently described Quantitative Direct Plating procedure in which heparinized blood (0.5 ml each) is plated onto blood and chocolate agar plates. Additionally, blood was cultured by means of the radiometric Bactec technique. In the case of H. influenzae and S pneumoniae, 23 (92%) of 25 patients with more than 100 organisms per milliliter of blood had meningitis or epiglottitis in contrast to only four (9.5%) of 42 patients with less than 100 organisms (P less than .001). No significant difference was noted in the magnitude of bacteremia due to N meningitidis among 12 patients with meningitis or other serious infections. The possible predictive value of the quantitation of bacteremia is illustrated by the observation of three children with seemingly mild respiratory infection and counts in excess of 100 organisms per milliliter who, within 20 hours, developed meningitis or epiglottitis. High bacterial counts of H influenzae and S pneumoniae in excess of 100 organisms per milliliter of blood should alert the physician to the existence or possible development of serious disease.