Penicillin-resistant Streptococcus pneumoniae in Iran.
OBJECTIVE
To determine the prevalence of penicillin-resistant Streptococcus pneumoniae isolated from patients with community-acquired pneumococcal infections.


METHODS
A broth dilution method was used to determine the minimum inhibitory concentration (MIC) of penicillin and other commonly used antibiotics. 115 heavy growth or pure culture of S. pneumoniae strains were isolated from: blood 10, cerebrospinal fluid (CSF) 15, ear 5, eye 12, purulent rhinosinusitis 48, sputum 22, and pleural fluid 3.


RESULTS
Of the 115 pneumococcoal isolates, 76 (66.1%) were sensitive to penicillin while the remaining 39 (33.9%) were nonsusceptible (15.6% resistant and 18.3% intermediately resistant). Among the 25 pneumococcal isolates from sterile sites (blood 15, CSF 10), 15 (60%) were penicillin-resistant whereas among the 90 isolates from nonsterile sites, 24 (26.7%) were resistant to penicillin (<0.004). The MIC values of antibiotics tested for S. pneumoniae were: penicillin 0.008-4 microg/ml, chloramphenicol 0.25-32 microg/ml, erythromycin 0.008-128 microg/ml, tetracycline 0.06-64 microg/ml, vancomycin 0.03-0.5 microg/ml, azithromycin 0.016-128 microg/ml, ciprofloxacin 0.006-8 microg/ml, cefotaxime 0.007-2 microg/ml, and ceftriaxone 0.016-12 microg/ml.


CONCLUSIONS
Approximately one third of S. pneumoniae isolated from the clinical specimens were nonsusceptible to penicillin in this region.
Kohanteb
Jamshid
J
Department of Medical Microbiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. kohanj@sums.ac.ir
Sadeghi
Esmaeel
E
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D010403:Penicillin Resistance; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013296:Streptococcus pneumoniae / Q000187:drug effects*
D000900:Anti-Bacterial Agents