Fundamental and clinical studies on Ceftazidime in suppurative otitis media

Abstract

To objectively evaluate the clinical efficacy and safety of Ceftazidime (CAZ) in treating suppurative otitis media, a standard protocol was designed and carried out in a multi-center clinical study. CAZ was examined for its sensitivity distribution against different clinical strains and its transfer into mucosal tissues of middle ear and otorrhea. 1. The MIC₈₀ of CAZ was 6.25 μg/ml for 49 strains of gram-positive bacteria (34 of them were strains of _{S. aureus}) and 3.13 μ g/ml for 22 strains of gram-negative bacteria (8 of them were _{P. aeruginosa}). These strains were all isolated from patients with suppurative otitis media. CAZ had stronger antibacterial activity than the three other antibiotics used for comparison (cefpiramide, cefotiam, and cefazolin). 2. The peak concentrations of CAZ (1 g, i. v.) was 33.8μg/g in the mucosal tissue of the middle ear and 27.9μg/ml in otorrhea, at 30 minutes and 60 minutes after administration, respectively. 3. Clinical evaluation of CAZ was made in 68 patients Clinical effectiveness was made in 63, clinical usefulness in 64. Safety was evaluated in all 68 patients. The dose of CAZ was 1g, twice daily, for most of the patients (59, 86.8%), and the duration of the administration was longer than 5 days, but not exceeding 7 days for 36 patients (52.9%). 4. The clinical efficacy rate assessed by the Efficacy Assessment Committee was rated at 76.2% (48/63), while the doctors in charge rated CAZ to have an efficacy of 74.6% (47/63). The percentage of “Excellent” cases was 57.1% in the assessment by the Committee. The efficacy rates (“Excellent” plus “Good”) in the committee assessment were 100% against acute suppurative otitis media (8 cases), 76.1% against acute exacerbation of chronic suppurative otitis media (46 cases), and 55.6% against chronic suppur- ative otitis media (9 cases). 5. The bacterial elimination rate was 86.0% in the assessment for each case (57 cases) and 87.0% in the assessment for each clinical strain (69 strains). The elimination rate for each species, excluding P. putida (2 strains), and X. maltophilia (1 strain), ranged from 82.4% to 100%. 6. Clinically adverse events were observed in 2 of the 68 patients; one case of rash and induction of an asthmatic attack in the other. Laboratory findings showed a decrease in white blood cell count in 1 case. None of these adverse events or abnormal laboratory findings were judged to be serious. In conclusion, CAZ is considered to be very useful in the treatment of suppurative otitis media.