Ceftriaxone kinetics and cerebrospinal fluid penetration in infants and children with meningitis.

20 patients (0.4-5.6 years old) receiving ceftriaxone for the treatment of bacterial meningitis were studied. Simultaneous serum and cerebrospinal fluid concentrations of ceftriaxone were determined by HPLC in 15 patients at 11.4-12.8 h after an intravenous loading dose of 75 mg/kg. Serum and cerebrospinal fluid concentrations ranged from 20.5 to 44.9 (31.3 +/- 7.8) and from 1.1 to 8.0 (3.7 +/- 1.8) micrograms/ml, respectively. Cerebrospinal fluid concentrations ranged from 3 to 25% (12 +/- 6%) of the simultaneous serum concentrations. In 6 patients, serum and cerebrospinal fluid concentrations were determined after maintenance doses of 50 mg/kg/12 h. Serum and cerebrospinal fluid concentrations ranged from 120 to 144 and 2.3-4.9 micrograms/ml at 1.8-5.5 h after the first maintenance dose in 2 patients; 74-139 and 5.7-7.9 micrograms/ml at 1.3-5.8 h after the second dose in 3 patients and was 101 and 4.1 micrograms/ml at 4 h after the 3rd dose in 1 patient. Multiple blood samples were collected after the loading dose in 5 patients and after 9-10 days of maintenance doses in 3 patients. Steady-state peak and trough serum concentrations ranged from 295 to 440 and 32.6-44.8 micrograms/ml, respectively. After the loading and maintenance dose at steady-state, total body clearance averaged 1.17 and 0.64 ml/min (p = 0.01); apparent volume of distribution averaged 0.37 and 0.26 l/kg (p greater than 0.05); and elimination half-life averaged 3.7 and 4.6 h (p = 0.01), respectively. These results suggest that (1) adequate cerebrospinal fluid concentrations of ceftriaxone can be achieved in patients with meningitis with the dosage regimen studied.(ABSTRACT TRUNCATED AT 250 WORDS)