Abstract
Cefmenoxime (CMX) was evaluated for its absorption and excretion as well as for therapeutic effectiveness in neonates and premature infants, The following results were obtained.
1. Serum concentrations of the drug were examined in 3 premature infants 1 to 11 days old upon intravenous administration of about 10mg/kg body weight (1st group), in 2 premature infants 18 and 32 days old and 1 neonate 17 days old upon intravenous administration of about 20mg/kg (2nd group), and in 1 neonate 15 days old with meningitis upon intravenous administration of 45.2mg/kg. Concentrations of CMX at 30 minutes after administration were 43, 29 and 27μg/ml, respectively, in the 1st group, 46, 37 and 44μg/ml, respectively, in the 2nd group and 208μg/ml in the other neonate, and appeared to be dose-dependent. Concentrations of CMX at 6 hours after administration were 18.2, 6.6 and 8.1μg/ml, respectively, in the 1st group, 9.6, 11 and 1.35μg/ml, respectively, in the 2nd group and 5.2μg/ml in the other subject. Serum half-lives were, respectively, 4.59, 2.85 and 3.48 hours in the 1st group, 2.52, 2.73 and 1.14 hours in the 2nd group and 1.0 hour in the other subject.
Urinary recovery rates during the first 6 hours after administration were 45.8, 87.0, 50.2 and more than 100% in 4 cases examined. Two of these cases, in which recovery rates were 45.8 and 50.2%, were premature infants of low birth weight.
Spinal fluid concentrations of the drug at 80 to 90 minutes after dosing to 1 neonate with purulent meningitis (causative organism presumed: Escherichia coli) given 48.3mg/kg tended to decline gradually with the recovery of the disease, 3.8, 1.72 and 1.32μg/ml on the 2nd, 6th and 8th day, respectively.
2. The drug was given to 9 neonates 0 to 24 days old. The therapeutic effectiveness on bacterial infections was evaluated in 7 cases (10 diseases) including 1 disease of purulent meningitis presumably caused by E. coli, 4 of septicemia caused by E. coil, Staphylococcus aureus and Streptococcus agalactiae (1, 2 and 1, respectively), 3 of urinary tract infection caused by E. coil, Serratia and Enterococcus faecalis (1 each), 1 of purulent parotitis caused by S. aureus and 1 of pneumonia (causative organism was unknown). Therapeutic efficacies were assessed as “Excellent” in all of meningitis, septicemia and urinary tract infection cases, and “Good” in 1 each of purulent parotitis and pneumonia cases.
For prophylactic use, the drug was given to 2 newborn infants in intravenous doses of 18.9 to 28.8mg/kg b. i. d. or t. i. d., and no infection occurred in any cases.
3. No adverse reactions were obtained in any of the 9 cases described above. Slight and transient increase in GPT was observed in 1 case.
4. These results suggested that CMX would be useful for the treatment of neonatal bacterial infections.
