Prevalência de sorotipos e resistência antimicrobiana de cepas invasivas do pneumococo em crianças: análise de 9 anos

Objective: To determine the prevalence of serotypes and antimicrobial susceptibility of strains of pneumococcus in children and to evaluate the implications for vaccine formulation.Methods: Strains of pneumococcus obtained from children admitted with invasive diseases were isolated at Hospital de Clinicas of Universidade Federal de Uberlandia, Uberlandia, Brazil, and sent to Instituto Adolfo Lutz, São Paulo, Brazil, for further identification, serotyping, and determination of antimicrobial susceptibility.Results: From April 1999 to December 2008, 142 strains of pneumococcus, obtained from children under 5 years of age, were analyzed. Seventy-five (52.8%) patients were male, and the age ranged from 1 to 60 months (mean age = 19 +/- 15.4 months; median = 15 months). the most common diagnoses were pneumonia [92 cases (64.8%)] and meningitis [33 cases (23.2%)]. the strains were mostly isolated from blood [61 samples (43%)], pleural fluid [52 samples (36.6%)], and cerebrospinal fluid [28 samples (19.7%)]. the most common serotypes were 14, 5, 6B, 1, 6A, 18C, 19A, 3, 9V, 19F, 23F, 9N, and 10A. There were 14 [9.9%] penicillin-resistant strains, which was detected only in the following serotypes: 14, 6B, 19F, 19A, and 23F, being predominant from 2004 to 2008 (p = 0.000). There was reduced susceptibility to co-trimoxazole (79.5%), erythromycin and clindamycin (11.3% each), and ceftriaxone (5.6%).Conclusions: Penicillin resistance was detected in 9.9% of the strains, being predominant from 2004 to 2008. Twenty different pneumococcal serotypes were identified, and 71.9% of the serotypes were represented in the 7-valent conjugate vaccine (PN CRM7) currently available.Univ Fed Uberlandia, Fac Med, Programa Posgrad Ciencias Saude, BR-38400 Uberlandia, MG, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilUniv Fed Uberlandia, Lab Hosp Clin Uberlandia, Uberlandia, MG, BrazilUniv São Paulo, Microbiol Clin, São Paulo, BrazilIAL, Secao Bacteriol, Projeto Sistema Reg Vacinas SIREVA, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilWeb of Scienc

Distribution of serotypes, antimicrobial resistence and molecular pattern od Strepococcus pneumoniae isolated from invasive infections in Brazil: 1993 through 1998

BV UNIFESP: Teses e dissertaçõe

Nasopharyngeal colonization and antimicrobial resistance of Streptococcus pneumoniae isolated in children with acute rinofaringitis

OBJECTIVE: to determine the prevalence and risk factors for nasopharyngeal colonization by, and to evaluate antimicrobial susceptibility of Streptococcus pneumoniae strains in children with acute rhinopharyngitis. METHODS: we collected nasopharyngeal swab specimens from 400 children aged 3 months to 5 years and with clinical status of acute rhinopharyngitis from June 16, 1997 to May 20, 1998 at the outpatient clinics of two hospitals in the city of São Paulo. Nasopharyngeal specimens were collected pernasally using a calcium alginate swab and plated immediately after collection onto trypticose soy agar with 5% sheep blood and garamicin 5 mcg/ml. Penicillin susceptibility was determined by oxacillin 1 mcg disk screening test and the minimal inhibitory concentration by the E-test. RESULTS: Pneumococci were recovered from 139 children, indicating a colonization prevalence of 35%. The risk factors analyzed indicated that the colonization was more prevalent in children attending day-care centers, children with siblings younger than 5 years, and children with recent use of antimicrobial agents. The prevalence of penicillin non-susceptible strains was of 16 % (20 strains). All strains were intermediately resistant (0.1mcg/ ml < MIC < 1.0 mcg/ ml). Out of the penicillin intermediately resistant strains, 7 (37%) showed intermediate resistance to cotrimoxazol and 2 (11%) full resistance to trimethoprim-sulfamethoxazole. No strains were resistant to ceftriaxone, amoxicillin, clarithromicin, or chloramphenicol. CONCLUSIONS: our findings indicate that the prevalence of nasopharyngeal colonization by Streptococcus pneumoniae in children with upper respiratory infections was of 34.8%. Children attending day-care centers and children with younger siblings showed higher levels of colonization The results of prevalence of bacterial resistance were similar to those of studies regarding invasive infections, thus indicating that nasopharyngeal isolates of Streptococcus pneumoniae can be used in the surveillance of antimicrobial resistance in a defined geographical area.OBJETIVO: avaliar a prevalência e os fatores de risco para a colonização nasofaríngea e determinar o padrão de suscetibilidade à penicilina de cepas isoladas da nasofaringe de crianças com rinofaringite aguda. METODOLOGIA: No período de 16/6/97 a 20/5/98 foram coletados 400 Swabs da nasofaringe de crianças com idade entre três meses e cinco anos que apresentavam quadro clínico de rinofaringite aguda. A identificação do S. pneumoniae foi realizada através do teste de optoquina e solubilidade em bile. Todas as cepas foram triadas através do disco de oxacilina 1mg, sendo avaliada, posteriormente, a concentração inibitória mínima para penicilina pelo método do E-teste. RESULTADOS: A prevalência da colonização nasofaríngea pelo S. pneumoniae foi de 35%. A análise dos fatores de risco associados à colonização nasofaríngea indicou que as crianças que eram institucionalizadas e que tinham irmãos menores de cinco anos apresentaram uma taxa maior de colonização. A prevalência de cepas não suscetíveis à penicilina foi de 16%. Todas as cepas apresentaram resistência intermediária (0,1mcg/ ml £ CIM £ 1,0 mcg/ ml ). Das 19 cepas com resistência à penicilina, 7 tinham resistência intermediária (37%), e duas (11%) resistência elevada ao cotrimoxazol. Não foi observada resistência à ceftriaxona, amoxicilina, claritromicina ou cloranfenicol. CONCLUSÕES: Concluímos que a prevalência da colonização nasofaríngea pelo pneumococo, em crianças menores de cinco anos com quadro de rinofaringite aguda, foi de 34,8%; as que eram institucionalizadas e tinham irmãos menores apresentaram uma maior taxa de colonização. A resistência à penicilina ocorreu em 15,6% dos isolados, não sendo detectada nenhuma cepa com resistência elevada. A taxa de resistência bacteriana encontrada foi bastante próxima à encontrada em estudo de infecções invasivas. Este fato sugere que os isolados de pneumococo da nasofaringe de crianças com infecção respiratória alta podem ser usados na vigilância da resistência antimicrobiana numa determinada comunidade.Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM)Santa Casa de São Paulo setor de Infectologia PediátricaInstituto Adolfo Lutz setor de bacteriologiaUNIFESP, EPMSciEL

Expansion of the multidrug-resistant clonal complex 320 among invasive Streptococcus pneumoniae serotype 19A after the introduction of a ten-valent pneumococcal conjugate vaccine in Brazil.

BackgroundIn 2010, a ten-valent pneumococcal conjugate vaccine (PCV10) was introduced in the routine infant national immunization program in Brazil. Invasive pneumococcal disease (IPD) caused by serotype 19A (Spn19A) increased after the introduction of PCVs in several countries. We compared the frequency, antimicrobial resistance and molecular patterns of invasive Spn19A strains before and after PCV10 introduction in Brazil using data from the national laboratory-based surveillance.MethodsWe analyzed invasive Spn19A strains isolated from 2005-2009 (pre-PCV10 period), 2011-2015 and 2016-2017 (post-PCV10 periods). Antimicrobial susceptibility was performed for all Spn19A strains, and multilocus sequence typing (MLST) was performed for strains isolated in the age groups ResultsAmong the study period, a total of 9,852 invasive Spn strains were analyzed, and 673 (6.8%) belonged to serotype 19A. Overall, the proportion of Spn19A among the total number of IPD strains increased from 2.8% in 2005-2009 to 7.0% and 16.4% in 2011-2015 and 2016-2017, respectively. The relative increase in Spn19A was observed especially in children ConclusionWe observed an expansion of MDR-CC320 among invasive Spn19A strains after PCV10 introduction in Brazil, probably related to a combination of factors, such as vaccination and antimicrobial pressure. Continued surveillance of Spn19A strains is necessary to monitor the sustainability of this clonal complex in the Brazilian population

Serotype Distribution and Antimicrobial Susceptibility Pattern of <i>Streptococcus pneumoniae</i> in COVID-19 Pandemic Era in Brazil

Despite the introduction of the pneumococcal vaccine, Streptococcus pneumoniae remains a cause of invasive diseases in Brazil. This study provides the distribution of serotypes and antimicrobial susceptibility patterns for pneumococcal isolates before and during the years of the COVID-19 pandemic in two age groups, S. pneumoniae from the pre-COVID-19 (January 2016 to January 2020) and COVID-19 (February 2020 to May 2022) periods. Antimicrobial resistance was evaluated by disk diffusion and minimum inhibitory concentration. The year 2020 was marked by a 44.6% reduction in isolates received and was followed by an upward trend from 2021 onwards, which became evident in 2022. No differences were observed in serotypes distribution between the studied periods. The COVID-19 period was marked by the high prevalence of serotypes 19A, 3, and 6C in both age groups. Serotypes 19A and 6C were related to non-antimicrobial susceptibility. We observed a reduction in S. pneumoniae, without changes in serotypes distribution and epidemiological capsular switch during the COVID-19 period. We observed elevated resistance rates, mainly to penicillin and ceftriaxone for non-meningitis cases in children under 5 years of age

Nasopharyngeal colonization by Streptococcus pneumoniae in children with sickle cell disease receiving prophylactic penicillin

OBJECTIVES: To determine the prevalence of nasopharyngeal pneumococcus colonization in children with sickle cell disease undergoing penicillin prophylaxis, to identify risk factors for colonization and to serotype and determine antibiotic resistance in pneumococci obtained from those children. METHODS: Between April 9, 2002 and February 28, 2003, 188 nasopharyngeal swabs were obtained from 98 children with sickle cell disease in follow-up at the Hospital São Paulo - Universidade Federal de São Paulo (UNIFESP). Pneumococci were isolated and identified by standard methods. The minimal inhibitory concentration for penicillin was determined by the E-test method. Isolates were serotyped with the use of type-specific antisera for 46 different serotypes (Neufeld-Quellung reaction). RESULTS: The age of children ranged from 4 months to 17 years (median and standard deviation 6.8±4.7 years). Thirteen of the 98 children had nasopharyngeal pneumococcus colonization (13.3% prevalence). There was a significantly greater risk of colonization among children less than 2 years old (p = 0.02). Twenty-one percent of isolates had intermediate penicillin resistance. There were no isolates highly resistant to penicillin. All isolates were susceptible to erythromycin, ceftriaxone, or vancomycin. The most frequently identified serotypes were 18C and 23F. CONCLUSIONS: Penicillin prophylaxis reduced pneumococcal nasopharyngeal colonization and did not increase the prevalence of penicillin-resistant pneumococci in children with sickle cell disease. Penicillin can be used not only for prophylaxis, but also in the acute management of febrile states with these children.OBJETIVOS: Determinar a prevalência de colonização nasofaríngea pelo pneumococo em crianças com doença falciforme, em uso de profilaxia com penicilina; identificar fatores de risco para colonização; sorotipar as cepas isoladas e avaliar a resistência antimicrobiana. METODOLOGIA: Foram colhidos 188 suabes de nasofaringe de 98 crianças com doença falciforme em acompanhamento no Hospital São Paulo, da Universidade Federal de São Paulo (UNIFESP), no período de 09 de abril de 2002 a 28 de fevereiro de 2003. O isolamento e a identificação dos pneumococos seguiram procedimentos padronizados. A concentração inibitória mínima para penicilina foi determinada pelo método do E-test. A sorotipagem foi realizada pela reação de Neufeld-Quellung com anti-soros para 46 sorotipos. RESULTADOS: A idade variou de 4 meses a 17 anos (média e desvio padrão de 6,8±4,7 anos). Das 98 crianças do estudo, 13 apresentaram colonização pelo pneumococo (prevalência de 13,3%). O maior risco de colonização ocorreu em menores de 2 anos de idade (p = 0,02). A prevalência de cepas com resistência intermediária à penicilina foi de 21,4%, não sendo evidenciada resistência plena. Também não houve cepas resistentes à eritromicina, ceftriaxona e vancomicina. Os sorotipos isolados mais freqüentes foram o 18C e o 23F. CONCLUSÕES: O uso profilático de penicilina diminuiu a colonização nasofaríngea pelo pneumococo e não determinou aumento da resistência a esse antimicrobiano nas crianças com doença falciforme. A penicilina ainda pode ser usada na profilaxia e no tratamento dos episódios febris dessas crianças