Abstract
Background:
The emergence of infection caused by invasive penicillinnonsusceptible (PNS) and multidrug-resistant strains of Streptococcus pneumoniae has become a worldwide concern, necessitating the epidemiologic surveillance of such strains.
Objectives:
One aim of this study was to identify clones of invasive PNS S pneumoniae among isolates in Riyadh, Saudi Arabia. The second aim was to compare these clones with international clones to track their spread in Saudi Arabia.
Methods:
The phenotypes of invasive isolates characterized as S pneumoniae were determined using susceptibility testing and serotyping (capsular test and E-test). The genotypes of PNS isolates were determined using random amplified polymorphic DNA analysis. The genetic relatedness of these local strains to the international widespread clones was investigated.
Results:
Of 296 S pneumoniae isolates identified using biochemical and culture characteristics, 89 (30.1%) were invasive. Susceptibility testing using the E-test revealed that 17 of the 89 invasive isolates (19.1%) were PNS. Most of the 89 isolates (89.9%) were resistant to sulfamethoxazole-trimethoprim; 32.6% and 23.6% of isolates were resistant to chloramphenicol and tetracycline, respectively. All of the isolates (100.0%) were fully susceptible to ceftriaxone and vancomycin. Capsular serotyping of the 89 isolates showed that 19A (18.0%), 613 (14.6%), 23F (13.5%), 9V (11.2%), 14 (6.7%), 19F (5.6%), and 18C (4.5%) were the most predominant serogroups/serotypes. The 17 PNS strains were confirmed on polymerase chain reaction to have penicillin resistance genes. Of these 17 strains, international clone 19A-a was the most predominant (41.2%), followed by 6B-a (17.6%), and 23F-a and 9V-a (each, 11.8%).
Conclusions:
The present study identified the spread of the 4 most commonPNS S pneumoniae isolates (clones)—19A, 613, 23F, and 9V-to Riyadh, but identified no new clones among patients having invasive infection with S pneumoniae in Riyadh. This study emphasizes that international PNS clones have contributed to the prevalence and spread of PNS pneumococci among the clinical isolates in Saudi Arabia.
Keywords: Streptococcus pneumoniae, susceptibility, serotyping, randomamplified polymorphic DNA analysis
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References
- 1.Bogaert D., Syrogiannopoulos G.A., Grivea I.N. Molecular epidemiology of penicillin-nonsusceptible Streptococcus paeumoaiae among children in Greece. J Clin Microbiol. 2000;38:4361–4366. doi: 10.1128/jcm.38.12.4361-4366.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Rudolph K.M., Parkinson A.J., Roberts M.C. Molecular analysis by pulsed-field gel electrophoresis and antibiogram of Streptococcus paeumoaiae serotype 6B isolates from selected areaswithin the United States. J Clin Microbiol. 1998;36:2703–2707. doi: 10.1128/jcm.36.9.2703-2707.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Twum-Danso K., Al-Mazrou A.M., Kambal A.M., Al-Zamil F.A. Penicillin resistance in serogroups/serotypes of Streptococcus paeumoaiae causing invasive infections in Central Saudi Arabia. Saudi Med J. 2003;24:1210–1213. [PubMed] [Google Scholar]
- 4.Dunne W.M., Jr, K.S. Kehl, Holland-Staley C.A. Comparison of results generated by serotyping, pulsed-field restriction analysis, ribotyping, and repetitive-sequence PCR used to characterize penicillin-resistant pneumococci from the United States. J Clin Microbiol. 2001;39:1791–1795. doi: 10.1128/JCM.39.5.1791-1795.2001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Overweg K., Hermans P.W., Trzcinski K. Multidrug-resistant Streptococcus pneumoniae in Poland: Identification of emerging clones. J Clin Microbiol. 1999;37:17391745. doi: 10.1128/jcm.37.6.1739-1745.1999. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Hermans P.W., Sluijter M., Hoogenboezem T. Comparative study of five different DNA fingerprint techniques for molecular typing of Streptococcus paeumoaiae strains. J Clin Microbiol. 1995;33:1606–1612. doi: 10.1128/jcm.33.6.1606-1612.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Vilhelmsson S.E., Tomasz A., Kristinsson K.G. Molecular evolution in a multidrugresistant lineage of Streptococcus paeumoaiae: Emergence of strains belonging to the serotype 6B Icelandic clone that lost antibiotic resistance traits. J Clin Microbiol. 2000;38:1375–1381. doi: 10.1128/jcm.38.4.1375-1381.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Memish Z.A., Shibl A.M., Ahmed Q.A. Guidelines for the management of community-acquired pneumonia in Saudi Arabia: A model for the Middle East region. Int J Aatimicrob Agents. 2002;20(Suppl 1):S1–S12. doi: 10.1016/s0924-8579(02)00243-1. [DOI] [PubMed] [Google Scholar]
- 9.Silverstein M., Bachur R., Harper M.B. Clinical implications of penicillin and ceftriaxone resistance among children with pneumococcal bacteremia. Pediatr Infect Dis J. 1999;18:35–41. doi: 10.1097/00006454-199901000-00010. [DOI] [PubMed] [Google Scholar]
- 10.Smith A.M., Botha R.F., Koornhof H.J., Klugman K.P. Emergence of a pneumococcal clone with cephalosporin resistance and penicillin susceptibility. Antimicrob Agents Chemother. 2001;45:2648–2650. doi: 10.1128/AAC.45.9.2648-2650.2001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Olive D.M., Bean P. Principles and applications of methods for DNA-based typing of microbial organisms. J Clin Microbiol. 1999;37:1661–1669. doi: 10.1128/jcm.37.6.1661-1669.1999. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Truong T.L., Menard C., Mouton C., Trahan L. Identification of mutants and other oral streptococci by random amplified polymorphic DNA analysis. J Med Microbiol. 2000;49:63–71. doi: 10.1099/0022-1317-49-1-63. [DOI] [PubMed] [Google Scholar]
- 13.McEllistrem M.C., Stout J.E., Harrison L.H. Simplified protocol for pulsed-field gel electrophoresis analysis of Streptococcus paeumoaiae. J Clin Microbiol. 2000;38:351–353. doi: 10.1128/jcm.38.1.351-353.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Greenberg D., Dagan R., Muallem M., Porat N. Antibiotic-resistant invasive pediatric Streptococcus paeumoaiae clones in Israel. J Clin Microbiol. 2003;41:5541–5545. doi: 10.1128/JCM.41.12.5541-5545.2003. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Greenberg D., Speert D.P., Mahenthiralingam E. Emergence of penicillinnonsusceptible Streptococcus paeumoaiae invasive clones in Canada. J Clin Microbiol. 2002;40:68–74. doi: 10.1128/JCM.40.1.68-74.2002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.National Committee for Clinical Laboratory Standards (NCCLS) Approved Standard M7-A6. 6th ed. 2003. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. Wayne Pa. [Google Scholar]
- 17.Arai S., Konda T., Wad A. Use of antiserum-coated latex particles for serotyping Streptococcus paeumoaiae. Microbiol Immunol. 2001;45:159–162. doi: 10.1111/j.1348-0421.2001.tb01284.x. [DOI] [PubMed] [Google Scholar]
- 18.Sloas M.M., Barrett F.F., Chesney P.J. Cephalosporin treatment failure in penicillinand cephalosporin-resistant Streptococcus paeumoaiae meningitis. Pediatr Infect Dis J. 1992;11:662–666. [PubMed] [Google Scholar]
- 19.Memish Z.A., Balkhy H.H., Shibl A.M. Streptococcus paeumoaiae in Saudi Arabia: Antibiotic resistance and serotypes of recent clinical isolates. Int J Antimicrob Agents. 2004;23:32–38. doi: 10.1016/j.ijantimicag.2003.05.008. [DOI] [PubMed] [Google Scholar]
- 20.Lee N.Y., Song J.H., Kim S. Carriage of antibiotic-resistant pneumococci among Asian children: A multinational surveillance by the Asian Network for Surveillance of Resistant Pathogens (ANSORP) Clin Infect Dis. 2001;32:1463–1469. doi: 10.1086/320165. [DOI] [PubMed] [Google Scholar]
- 21.Song J.H., Lee N.Y., Ichiyama S. Spread of drug-resistant Streptococcus pneumoniae in Asian countries: Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study. Clin Infect Dis. 1999;28:1206–1211. doi: 10.1086/514783. [DOI] [PubMed] [Google Scholar]
- 22.McGee L., McDougal L., Zhou J. Nomenclature of major antimicrobial-resistant clones of Streptococcus paeumoaiae defined by the pneumococcal molecular epidemiology network. J Clin Microbiol. 2001;39:2565–2571. doi: 10.1128/JCM.39.7.2565-2571.2001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Scott J.A., Hall A.J., Dagan R. Serogroup-specific epidemiology of Streptococcus paeumoaiae: Associations with age, sex, and geography in 7,000 episodes of invasive disease. Clin Infect Dis. 1996;22:973–981. doi: 10.1093/clinids/22.6.973. [DOI] [PubMed] [Google Scholar]