Effectiveness of treatment with mezlocillin, ampicillin and latamoxef (moxalactam) of experimental group B beta-haemolytic streptococcal meningitis in rabbits.

This study compared the effectiveness of treatment with various antibiotics in rabbits with experimental group B beta-haemolytic streptococcal meningitis. Groups of nine infected rabbits each received the following treatments intramuscularly, three times per day: (1) control--no treatment; (2) mezlocillin--400 mg/kg/day; (3) mezlocillin--400 mg/kg/day + gentamicin--15 mg/kg/day; (4) ampicillin--400 mg/kg/day; (5) ampicillin--400 mg/kg/day + gentamicin 15 mg/kg/day; (6) latamoxef (moxalactam)--100 mg/kg/day. Bacterial counts in the cerebrospinal fluid (CSF) and drug levels in the serum and CSF were measured each hour for 7 h and at 24, 48 and 72 h after start of therapy. Percent penetration values (CSF concentration/serum concentration X 100) for the drugs were calculated and effectiveness of bacterial clearing from the CSF was determined. Over the 72 h period, the most effective therapy was mezlocillin + gentamicin, followed by ampicillin + gentamicin, mezlocillin, ampicillin and latamoxef in order of effectiveness in clearing bacteria from the CSF.