Caracteriza????o de cepas de streptococcus pneumoniae causadoras de doen??a invasiva na cidade de Salvador, Bahia

A doen??a pneumoc??cica invasiva (DPI) continua sendo uma das principais causas de morbidade e mortalidade no mundo, mesmo com a disponibilidade atual de terapias antimicrobianas e vacinas conjugadas. O objetivo desse estudo foi caracterizar o perfil fenot??pico e genot??pico das cepas invasivas de Streptococcus pneumoniae isoladas de diferentes s??tos de infec????o que circulam em hospitais p??blicos e privados da cidade de Salvador-Brasil no per??odo de janeiro de 2008 a julho de 2011. Os isolados de S. pneumoniae de doen??a invasiva foram identificados por m??todos microbiol??gicos cl??ssicos e submetidos ?? determina????o capsular atrav??s da t??cnica de Multiplex-PCR. A sensibilidade aos antimicrobianos foi determinada pela t??cnica de microdilui????o em caldo. A caracteriza????o genot??pica foi realizada por PFGE e MLST. No per??odo do estudo foram identificados 75 casos de DPI com cultura positiva, sendo 82,7% provenientes de hemocultura, 9,3% de l??quido pleural e 8,0% de l??quor. As crian??as representaram 37,9% e os idosos 24,0% da popula????o em estudo. Os sorotipos mais prevalentes foram o 14 (14,7%), 19F (13,3%), 6B (10,7%), 23F (9,3%), 3 (9,3%) e 19A (6,7%). Um total de 57,3% dos sorotipos identificados est??o representados na vacina PCV10. N??o-susceptibilidade ?? penicilina (CIM ??? 4??g/mL) foi observada em 5,3% dos isolados. Para o SMX-TMP, tetraciclina e eritromicina, os ??ndices de n??o-susceptibilidade foram de 55%, 15% e 11%, respectivamente. A tipagem por PFGE classificou 61,3% dos isolados de DPI como n??o-clonais e 29 (38,7%) em 10 perfis clonais. Quando comparados aos isolados de meningite isolados no Hospital Couto Maia, 22,7% apresentaram perfis semelhantes, que foram distribu??dos em seis grupos clonais (quatro grupos clonais com isolados n??o-suscept??veis ?? penicilina e dois sens??veis). Foram encontrados 22 STs diferentes entre as 26 amostras caracterizadas por MLST. Quando comparado aos clones j?? caracterizados pelo PMEN, verificou-se que na cidade de Salvador circulam clones j?? identificados em outros pa??ses, a exemplo dos clones: Colombia23F-26 (SLV 338), Portugal19F-21 (ST 177), Spain9V-3 (SLV 156) e Netherlands3-31 (ST 180). Os isolados de pneumococos deste estudo apresentam maior taxa de resist??ncia, incluindo resist??ncia a m??ltiplas drogas quando comparados aos dos casos de meningite identificados em casos de meningite, com exce????o da penicilina. Embora os clones mais frequentemente associados aos casos de meningite pneumoc??cia em Salvador tenham sido identificados nesta casuistica, os isolados de pneumococos provenientes de outras formas de doen??a invasiva apresentaram uma maior diversidade fenot??pica e genot??pica, ressaltando a import??ncia do monitoramento cont??nuo das cepas invasivas nas diferentes manifesta????es da doen??a pneumoc??cica no tempo das vacinas conjugadas.Invasive pneumococcal disease (IPD) remains one of the major causes of morbidity and mortality worldwide, even with the current availability of antimicrobial therapies and conjugate vaccines. The objective of the present study was to characterize the phenotypic and genotypic profiles of invasive pneumococcal isolates obtained from patients admitted to public and private hospitals in Salvador, from the period of Jan/2008 to Jul/2011. The pneumococcal isolates from invasive disease were identified by classical microbiological methods and submitted to capsular deduction by multiplex-PCR. The antimicrobial susceptibility was performed by broth microdilution method. The genotypic profile was accessing by PFGE and MLST. During the study period, 75 consecutive culture-positive cases of IPD were characterized, being 82.7% from blood, 9.3% from pleural fluid and 8.0% from CSF. The study population comprised of 37.9% of children (under 5 years old) and 24.0% of elderly (upper 64 years old). The most prevalent serotypes were: 14 (14.7%), 19F (13.3%), 6B (10.7%), 23F (9.3%), 3 (9.3%) and 19A (6.7%). A total of 57.3% of the serotypes identified are represented in the vaccine PCV10. Non-susceptibility to penicillin (MIC ??? 4??g/mL) was observed in 5.3% of the isolates. The non-susceptibility rate for SMX-TMP, tetracycline and erythromycin was found in 55%, 15% and 11% of the isolates, respectively. The PFGE pattern analysis classified 61.3% of IPD isolates as non-clonal and 29 (38.7%) isolates were clustered in ten PFGE profiles. When the clonal strains were compared with pneumococcal meningitis isolates from Hospital Couto Maia, 22.7% showed similar profiles by PFGE, being distributed into six clonal groups (four clonal groups of penicillin non-susceptible and two of penicillin susceptible). Twenty-two STs were observed among the 26 samples characterized by MLST. When compared to already characterized PMEN clones, it was found that some circulating clones in the city of Salvador have been identified in other countries, such as: Colombia23F-26 (SLV 338), Portugal19F-21 (ST 177), Spain9V-3 (SLV 156) and Netherlands3-31 (ST 180). The pneumococcal strains in the study have a higher rate of resistance, including multidrug resistance when compared to cases of meningitis identified in the HCM, except for penicillin. Although the clones most frequently associated with cases of meningitis in Salvador have been identified in this study, isolates of pneumococci from other forms of IPD had a higher phenotypic and genotypic diversity, highlighting the importance of continuous monitoring of invasive strains in different manifestations of pneumococcal infection in the time of conjugate vaccines