The Incidence of Respiratory Tract Pathogens and Antimicrobial Susceptibilities of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella (Branhamella) catarrhalis Isolated between 1990 and 1993

• Published in: The Tohoku Journal of Experimental Medicine Vol. 179; no. 2; pp. 111 - 121
• Main Authors: Nishioka, Kiyo, Ogihara, Hisako, Ohno, Isao, Tanno, Yasuo, Shirato, Kunio
• Format: Journal Article
• Language: English
• Published: Japan Tohoku University Medical Press 1996
• Subjects: antimicrobial susceptibility; Drug Resistance, Microbial; Drug Resistance, Multiple; Haemophilus Infections - drug therapy; Haemophilus Infections - epidemiology; Haemophilus Infections - microbiology; Haemophilus influenzae - drug effects; Haemophilus influenzae - isolation & purification; Humans; Japan - epidemiology; Moraxella (Branhamella) catarrhalis - drug effects; Moraxella (Branhamella) catarrhalis - isolation & purification; Neisseriaceae Infections - drug therapy; Neisseriaceae Infections - epidemiology; Neisseriaceae Infections - microbiology; penicillin resistant S. pneumoniae; Pneumococcal Infections - drug therapy; Pneumococcal Infections - epidemiology; Pneumococcal Infections - microbiology; quinolone resistant H. influenzae; quinolone resistant M. (B) catarrhalis; respiratory pathogenic bacteria; Respiratory Tract Infections - drug therapy; Respiratory Tract Infections - epidemiology; Respiratory Tract Infections - microbiology; Streptococcus pneumoniae - drug effects; Streptococcus pneumoniae - isolation & purification; Japan
• ISSN: 0040-8727; 1349-3329
• DOI: 10.1620/tjem.179.111

Using a quantitative culture of sputum, the incidence of pathogenic bacteria in respiratory infection in our laboratory between 1990 and 1993 were investigated. While Haemophilus influenzae, Streptococcus pneumoniae and Moraxella (Branhamella) catarrhalis were isolated at high rates (67∼78%) from the specimens of outpatients throughout the study period, the incidence of S. pneumoniae has increased gradually. The antimicrobial susceptibilities of these three pathogens were examined with the agar dilution method. A marked increase of penicillin (PC) resistant S. pneumoniae (MIC≥0.1 μg/ml) was observed with a resistance rate of 2.1% in 1990 and 25% in 1993. Resistance to erythromycin (EM, MIC≥1.56 μg/ml) was 8.5% in 1990 but then increased to 34% in 1992. Most of the PC resistant isolates were resistant to multidrugs such as EM, minocycline and clindamycin. The MICs of all β-lactams examined for S. pneumoniae increased along with the MICs of PC, though the level varied between drugs. The rates of β-lactamase positive H. influenzae gradually decreased, being 14.3% in 1990 and 7.4% in 1993, whereas those of M. (B) catarrhalis were consistently high (>90%) every year. In addition to β-lactamase production, the emergence of strains of H. influenzae and M. (B) catarrhalis resistant to new quinolone drugs should be noted.