Changes of antibacterial sensitivity pattern in patients attended in our health area and diagnosed of low respiratory tract infection
Objectives: Determine the prevalence and pattern of sensitivity of the main etiological agents involved in the development of respiratory infections: Pseudomonas spp, Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis.
Material and methods: We studied 470 strains from 2006 to 2013, in patients attending in our Health Area diagnosed with respiratory infection being mostly sputum, bronchial aspirates, and biological fluids (pleural and bronchoalveolar lavage). The bacterial resistance was determined by study of the Minimum Inhibitory Concentration (E-test diffusion agar). Tested antibiotics: amoxicillin clavulanic (AMC); cefotaxime (CFT) and levofloxacine (LVF).
Results: A total of 470 isolates from respiratory samples, with the following distribution: Pseudomonas spp 226 (48.0%), H. influenzae 126 (26.8%), M. catarrhalis 75 (15.9%) and S. pneumoniae 43 (9.1%). The higher prevalence of isolated microorganisms was obtained in 2008, showing a decline in subsequent years (2011 – 2012). Antibacterial pattern sensitivity to antibiotics tested were the following.
*AMC: oscillations of sensitive isolates with an increase in 2009 to 2010.
*CFT: Most of the isolates were sensitive, except for 2009 and 2013.
*LVF: Progressive decrease from 2009, excepting 2010.
*CFT: Progressive decrease from 2009.
*LVF: Oscillations in prevalence with progressive decrease from 2009, excepting 2010.
*AMC/CFT/LVF: The number of sensitive isolates remains constant, excepting 2011 in which a significant decrease was observed.
*AMC/CFT/LVF: Variations in the prevalence of isolates susceptible, with a rise at end.
The percentages of bacterial sensitivity are similar to those obtained by other authors.
LVF may be more effective than cephalosporins for the respiratory pathogens studied. LVF present higher activity against S. pneumoniae and may be administered orally; for these reasons could be the antibiotic of choice in the treatment of respiratory infections.
LVF do not show resistance associated to penicillin resistance in S. pneumoniae, or β-lactamase producing in strains of H. influenzae and M. catarrhalis. Therefore could become the first-line treatment in certain infections caused by these pathogens.