RESUMO
Serum antibodies specific for the capsular polysaccharides of Streptococcus pneumoniae provide protection against invasive pneumococcal infection. In Brazil, this vaccine has been used for people over 65 years with clinical risk to develop pneumococcal infection since 1999. We evaluated the immune response of 102 elderly subjects (75.5% females and 24.5% males) with a mean age of 71 years, and 19 young healthy adults (63.2% females and 36.8% males) with a mean age of 27 years. The elderly study group consisted of outpatients who received follow-up care in the Geriatric Department of General Hospital, Faculty of Medicine, University of São Paulo. None had acute illness at the time of vaccination. Both groups were immunized with one intra-deltoid injection with 0.5 ml of a 23-valent pneumococcal polysaccharide vaccine. The total IgG specific antibody concentrations to capsular polysaccharides 1, 3, 5, 6B, 8, and 14 were determined against pre- and 1-month post-vaccination sera. All samples were analyzed according to the second-generation pneumococcal polysaccharide ELISA protocol. We observed that the pneumococcal polysaccharide vaccine evoked consistent antibody increase for serotypes 1, 5, 6B, 8, and 14 (geometric mean concentration increase of 2.46 in the elderly and 2.84 in the young adults). Otherwise, we observed no increase in antibody concentration for serotype 3 in both groups.
Assuntos
Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/imunologia , Brasil , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-IdadeRESUMO
Serum antibodies specific for the capsular polysaccharides of Streptococcus pneumoniae provide protection against invasive pneumococcal infection. In Brazil, this vaccine has been used for people over 65 years with clinical risk to develop pneumococcal infection since 1999. We evaluated the immune response of 102 elderly subjects (75.5 percent females and 24.5 percent males) with a mean age of 71 years, and 19 young healthy adults (63.2 percent females and 36.8 percent males) with a mean age of 27 years. The elderly study group consisted of outpatients who received follow-up care in the Geriatric Department of General Hospital, Faculty of Medicine, University of São Paulo. None had acute illness at the time of vaccination. Both groups were immunized with one intra-deltoid injection with 0.5 ml of a 23-valent pneumococcal polysaccharide vaccine. The total IgG specific antibody concentrations to capsular polysaccharides 1, 3, 5, 6B, 8, and 14 were determined against pre- and 1-month post-vaccination sera. All samples were analyzed according to the second-generation pneumococcal polysaccharide ELISA protocol. We observed that the pneumococcal polysaccharide vaccine evoked consistent antibody increase for serotypes 1, 5, 6B, 8, and 14 (geometric mean concentration increase of 2.46 in the elderly and 2.84 in the young adults). Otherwise, we observed no increase in antibody concentration for serotype 3 in both groups.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Fatores Etários , Anticorpos Antibacterianos/imunologia , Brasil , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/imunologiaRESUMO
PspA is an antigenically variable virulence factor of Streptococcus pneumoniae that inhibits complement deposition and is a potential candidate for human vaccines. Of 64 published strains 96% are in PspA families 1 and 2; optimal protection is family-specific. Effective development of a PspA-containing vaccine requires more information about the PspA family of strains in parts of the world where the vaccine is most needed. In these studies we observed that of 149 isolates (of 19 capsular types) from Argentina, 54.4% were family 1, 41.6% were family 2 and 4.0% expressed both family 1 and family 2 PspAs. Box typing revealed the Argentinian strains to be from at least 10 clonally related groups.
Assuntos
Proteínas de Bactérias/genética , Streptococcus pneumoniae/classificação , Criança , Pré-Escolar , Variação Genética , Humanos , Lactente , Recém-Nascido , Sorotipagem , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/imunologiaRESUMO
An on-going Streptococcus pneumoniae surveillance in Uruguay furnished national information on serotype distribution of isolates from invasive infections in children
Assuntos
Meningite Pneumocócica/imunologia , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/uso terapêutico , Pneumonia Pneumocócica/imunologia , Streptococcus pneumoniae/isolamento & purificação , Vacinas Conjugadas/uso terapêutico , Pré-Escolar , Humanos , Lactente , Meningite Pneumocócica/epidemiologia , Paraguai/epidemiologia , Resistência às Penicilinas , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/prevenção & controle , Pneumonia Pneumocócica/epidemiologia , Sorotipagem , Streptococcus pneumoniae/classificaçãoRESUMO
Pneumococcal surface protein A (PspA) elicits protection in mice against fatal bacteremia and sepsis caused by genetically diverse pneumococci and protects against carriage and lung infection. We determined the PspA families of invasive isolates of Streptococcus pneumoniae recovered from Colombian children <5 years of age. That 97.5% of Colombian isolates belong to PspA families 1 and 2 supports the hypothesis that a human PspA vaccine covering a few PspA families could be broadly effective.
Assuntos
Proteínas de Bactérias/classificação , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Streptococcus pneumoniae/classificação , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/classificação , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Pré-Escolar , Colômbia , DNA Bacteriano/análise , Humanos , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/imunologia , Reação em Cadeia da Polimerase , Coelhos , Sorotipagem , Streptococcus pneumoniae/imunologia , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/patogenicidadeRESUMO
BACKGROUND: Since 1993 the Pan American Health Organization has coordinated a surveillance network with the National Reference Laboratories of Argentina, Brazil, Chile, Colombia, Mexico and Uruguay aimed at monitoring capsular types and antimicrobial susceptibility of Streptococcus pneumoniae causing invasive disease in children <6 years of age. METHODS: The surveillance system included children 6 years of age and younger with invasive disease caused by S. pneumoniae. The identification, capsular typing and susceptibility to penicillin of the isolates were conducted using a common protocol, based on standard methodologies. RESULTS: By June, 1999, 4,105 invasive pneumococcal isolates had been collected mainly from pneumonia (44.1%) and meningitis (41.1%) cases. Thirteen capsular types accounting for 86.1% of the isolates (14, 6A/6B, 5, 1, 23F, 19F, 18C, 19A, 9V, 7F, 3, 9N and 4) remained the most common types during the surveillance period. Diminished susceptibility to penicillin was detected in 28.6% of the isolates, 17.3% with intermediate and 11.3% with high level resistance. Resistance varied among countries and increased during this period in Argentina, Colombia and Uruguay. Serotypes 14 and 23F accounted for 66.6% of the resistance. CONCLUSION: These surveillance data clearly demonstrate the potential impact of the introduction of a conjugate vaccine on pneumococcal disease and the need for more judicious use of antibiotics to slow or reverse the development of antimicrobial resistance.
Assuntos
Resistência às Penicilinas , Penicilinas/administração & dosagem , Infecções Pneumocócicas/tratamento farmacológico , Streptococcus pneumoniae/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , México , Penicilinas/uso terapêutico , Vigilância da População , Garantia da Qualidade dos Cuidados de Saúde , Controle de Qualidade , Sorotipagem , América do Sul , Streptococcus pneumoniae/classificaçãoRESUMO
In Colombia, penicillin resistance of Streptococcus pneumoniae invasive isolates recovered from children less than 5 years old has increased from 10% in 1994 to 49.4% in 1999, suggesting the circulation of international resistant clones in the country. A total of 167 S. pneumoniae invasive isolates with diminished susceptibility to penicillin (DSP) were studied. The techniques used were pulsed-field gel electrophoresis (PFGE) and restriction fragment length polymorphism (RFLP) of penicillin-binding proteins (PBPs) genes (2B, 2X, and 1A). Forty-nine serotype 23F isolates were grouped in two clusters: 15 (31%) multiresistant isolates showed PFGE pattern A and PBP I profile, thus making them indistinguishable from Spain23F-1 clone, and 34 (69%) with PFGE pattern C, PBP II profile, and intermediate level resistance (ILR) to penicillin and TMP-SMX, features unique to a Colombian clone. Fifty-five serotype 14 isolates were assigned to PFGE B pattern, PBP III profile, having high-level resistance to penicillin, and TMP-SMX, similar to the France9V variant 14. This same pattern was present in five capsular type 9V isolates. Four serotype 14 isolates were assigned to PFGE pattern F, and appeared to be similar to Slovakia(14)-10 PFGE pattern, although they had different PBP profiles. Nine capsular type 6B and one 6A isolates belonged to PFGE pattern M, similar to Spain6B-2, although they showed different PBP profiles. The remaining 44 isolates, corresponding to serotypes 14, 6B, 19F, and 34, showed variable PFGE and PBP patterns. These results show that as many as two international clones may be circulating in Colombia as well as a unique, widely distributed 23F clone with ILR to penicillin. Additionally, some Colombian isolates capsular type 14 and 6B might be related to Slovakia(14)-10 Spain6B-2 clones, respectively.
Assuntos
Proteínas de Bactérias , Hexosiltransferases , Peptidil Transferases , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Colômbia , Impressões Digitais de DNA , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Resistência Microbiana a Medicamentos , Eletroforese em Gel de Campo Pulsado , Humanos , Muramilpentapeptídeo Carboxipeptidase/genética , Muramilpentapeptídeo Carboxipeptidase/metabolismo , Resistência às Penicilinas , Proteínas de Ligação às Penicilinas , Fenótipo , Sorotipagem , Streptococcus pneumoniae/genéticaRESUMO
Pneumonia is one of the leading causes of hospitalization and death among children in developing countries, and mortality due to pneumonia has been associated with S. pneumoniae infection. This investigation was designed to describe the antimicrobial susceptibility and serotype patterns of pneumococcal strains recovered from the blood of children with community-acquired pneumonia (CAP) and to assess the clinical findings of pneumococcal bacteremic patients with pneumonia. In a 26 month prospective study, blood cultures were obtained as often as possible from children (<16 years of age) diagnosed with CAP in two emergency rooms. Antimicrobial drug susceptibility tests and serotyping were performed when pneumococcus was identified. We studied 3,431 cases and cultured blood samples from 65.5% of those. Pneumococcus was recovered from 0.8% of the blood samples. The differences in age, somnolence, wheezing and hospitalization among children with and without pneumococcal bacteremia were statistically significant. Pneumococcal bacteremia was age-related (mean 1.63 +/- 1.55; median 0.92) and associated with somnolence and hospitalization among children with CAP. One strain was recovered from pleural fluid. Penicillin resistance was detected in 21.0% (4/19) of the strains at an intermediate level, whereas 63.0% of the strains were resistant to trimethoprim-sulfamethoxazole. The most common serotypes were 14 and 6B, and these serotypes included the resistant strains. Eight of our 18 isolates from blood were of types included in the heptavalent conjugate pneumococcal vaccine, recently licensed in the USA.
Assuntos
Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Adolescente , Fatores Etários , Antibacterianos/farmacologia , Bacteriemia/sangue , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Brasil , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/sangue , Resistência Microbiana a Medicamentos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/sangue , Infecções Pneumocócicas/tratamento farmacológico , Pneumonia Pneumocócica/sangue , Pneumonia Pneumocócica/tratamento farmacológico , Pneumonia Pneumocócica/microbiologia , Estudos Prospectivos , Sorotipagem , Streptococcus pneumoniae/classificaçãoRESUMO
The impact of invasive pneumococcal invasive disease is increased by the emergence of antibiotic resistance. We report regional and temporal variations in antibiotic resistance for 4,105 invasive Streptococcus pneumoniae isolates collected from Latin American children <5 years, between 1993 and 1999. Reduced susceptibility to penicillin was detected in 1,182 isolates (28.8%); 36% of these were resistant (> or = 2 microg/ml), including 12.6% with MIC > or = 4 microg/ml, occurring primarily in serotypes 14 and 23F. Reduced susceptibility to third-generation cephalosporins was detected in 12.1% of the collection. Mexico had the highest proportion of reduced susceptibility to penicillin (51.6%) and to third-generation cephalosporins (22%), whereas Brazil had the lowest at 20.9% and 0.7%, respectively. Isolates cultured from patients with pneumonia were more likely to have reduced susceptibility to third-generation cephalosporins than isolates from patients with meningitis (p < 0.0001). Susceptibility to trimethoprim-sulfamethoxazole, chloramphenicol, erythromycin, and vancomycin was tested by disk diffusion for 2.899 isolates. Reduced susceptibility was observed for 45.6%, 11.5%, 6.9%, and 0%, respectively. Thirty-one percent of the strains were resistant to > or = 2 drugs. High levels of antibiotic resistance in Latin America emphasize the need for the development of and adherence to rational antibiotic use guidelines. On-going surveillance will monitor the impact of these programs.
Assuntos
Resistência a Medicamentos , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/metabolismo , Streptococcus pneumoniae/efeitos dos fármacos , Fatores Etários , Resistência às Cefalosporinas , Criança , Resistência a Múltiplos Medicamentos , Feminino , Hospitais Pediátricos , Humanos , América Latina/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Resistência às Penicilinas , Infecções Pneumocócicas/tratamento farmacológico , Controle de Qualidade , Sorotipagem , Resistência beta-LactâmicaRESUMO
Haemophilus influenzae is a relevant cause of morbidity and mortality among children under 5 years of age in the developing world. In Latin America, H. influenzae type b (Hib) conjugate vaccine and surveillance of H. influenzae antimicrobial susceptibility have been implemented in recent years. We have undertaken a systematic review and a pooled analysis on H. influenzae antimicrobial resistance, including reports of 15 Latin America countries over a 10-year period (1990-2000). We have found that 450 (21.4%) of 2,100 invasive isolates were beta-lactamase producers compared to 145 (14.5%) of 998 isolates of noninvasive isolates (p < 0.05). Ampicillin resistance was detected among 783 (21.9%) of 3,577 invasive isolates compared to 111 (17.2%) of 646 noninvasive strains (p < 0.05). In contrast, 568 (41.9%) of 1,355 noninvasive strains were trimethoprim-sulfamethoxazole (TMP-SMX) resistance against 241 (26.9%) of 897 invasive ones (p < 0.05). Therefore, TMP-SMX resistance was more common in nonsterile fluids than in sterile fluids. Over time, rates of beta-lactamase-producing strains were stable in Brazil and Mexico, whereas rates of TMP-SMX resistance were increasing in Brazil. It is predictable that following the Hib immunization, Latin America countries will be faced with increased nontypeable H. influenzae infection. Although standing by the nontypeable H. influenzae vaccine, in this novel epidemiological scenario of post-Hib vaccination in Latin America settings there is a need to improve H. influenzae resistance monitoring to guide clinicians to choose efficacious antimicrobial therapy.
Assuntos
Resistência a Medicamentos , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/metabolismo , Haemophilus influenzae/efeitos dos fármacos , Interpretação Estatística de Dados , Infecções por Haemophilus/tratamento farmacológico , Haemophilus influenzae/enzimologia , Humanos , América Latina/epidemiologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/microbiologia , Combinação Trimetoprima e Sulfametoxazol/farmacologia , beta-Lactamases/metabolismoRESUMO
Community-acquired pneumonia is one of the leading causes of infant morbidity and mortality. Studies conducted in developing countries indicate that the most serious symptoms of pneumonia are associated with bacterial causes, mainly Streptococcus pneumoniae, followed by Haemophilus influenzae type b. Managing those infections in children under two years of age is hindered by the lack of appropriate vaccines and by the decreased susceptibility of S. pneumoniae to penicillin and other antibiotics. In 1993, at the initiative of the Regional System for Vaccines of the Pan American Health Organization, and with funding from the Canadian International Development Agency, a study was designed to identify the S. pneumoniae capsular types that cause invasive disease in Latin American children under 5 years of age. The objective of the study was to determine the ideal composition of a conjugate vaccine that could be used in Latin America, and the penicillin susceptibility of the S. pneumoniae isolates. The initiative was undertaken in Argentina, Brazil, Chile, Colombia, Mexico, and Uruguay. This report analyzes the information that the participating countries generated on pneumococcal pneumonia. A total of 3,393 children were found with systemic S. pneumoniae infections, of which 1,578 corresponded to pneumonias. The analysis focused on 1,409 cases of pneumonia in Argentina, Brazil, Colombia, Mexico, and Uruguay. Of the children, 63.8% of them were under two years of age. Twelve prevalent capsular types were identified, of which serotypes 14, 5, and 1 were the three most common in the majority of the countries. At the beginning of the study the highest level of penicillin resistance was found in Mexico (47.0%), and the lowest in Colombia (12.1%). Over the 1993-1998 period, resistance to penicillin increased in the five countries. Penicillin resistance was associated with a small number of capsular serotypes, mainly 14 and 23F. The first of those serotypes was resistant to penicillin and to trimethoprim-sulfamethoxazole, and the second was multiresistant. The frequency of resistance to trimethoprim-sulfamethoxazole was high in all of the countries; Argentina had the highest level, 58.0%. A decrease in susceptibility to chloramphenicol was uncommon, except in Colombia, where there was a resistance level of 23.4%. Resistance to erythromycin was low in all the countries, and all the isolates were susceptible to vancomycin.
Assuntos
Pneumonia Pneumocócica/epidemiologia , Pré-Escolar , Humanos , Lactente , América Latina , Testes de Sensibilidade Microbiana , Vigilância da População , Sorotipagem , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacosRESUMO
In some countries, the invasive disease caused by Haemophilus influenzae type b (Hib) has been practically eliminated thanks to vaccination. However, in much of the developing world, meningitides and pneumonias caused by these bacteria continue to be a major cause of childhood morbidity and mortality, as well as high hospitalization costs. Because safe and effective conjugate vaccines are now available, the Special Program for Vaccines and Immunization of the Pan American Health Organization has recommended introducing them into the regular vaccination regimen of as many countries as possible. This has been done in Chile and Uruguay, where the Hib vaccine now forms part of the regular vaccination routine. When the vaccine was being introduced, both countries had difficulties they could have avoided if they had known of the experiences of other nations. Therefore, these two countries now offer the lessons they learned to other nations considering introducing the vaccine into their immunization programs. The most important lessons were to: strengthen the epidemiological surveillance system sufficiently in advance of introducing the vaccine; with the support of scientific societies, present the technical information that justifies introducing the vaccine; seek community backing and acceptance; precisely establish in advance the presentation and dosage of the vaccine that is most appropriate for the country; and be certain to have the political and legal decisions needed to ensure the continuity of Hib vaccination in the future.
Assuntos
Haemophilus influenzae tipo b/imunologia , Meningite por Haemophilus/epidemiologia , Vacinas Conjugadas , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Humanos , Esquemas de Imunização , Lactente , Masculino , Meningite por Haemophilus/imunologia , Meningite por Haemophilus/prevenção & controle , Uruguai/epidemiologia , VacinaçãoRESUMO
From January 1993 through December 1996, 1,252 Streptococcus pneumoniae strains from different geographic regions of Brazil were studied for penicillin (Pen) susceptibility. All pneumococci were isolated from normally sterile fluids from patients, newborns to 88 years old. Pen resistance (R) had a mean rate of 15.1%, with 14.5% of strains showing intermediate level Pen-R and 0.6% showing high-level Pen-R. Similar Pen-R rates were observed in different regions of the country, in the range of 9.5% to 17.1%. A Pen-R increase was noted from 9.6% in 1993 to 20.6% in 1996. Pen-R was mostly associated to serotypes 6B, 14, 19A, and 23F (89%). Chromosomal DNA relatedness of Pen-R strains was determined by pulsed field gel electrophoresis (PFGE). High genetic diversity was identified, being represented by 27 patterns among the 92 strains. Two important features were observed: the predominance of relatively low-level Pen MIC (range 0.1-0.5 mg/L) in 86 of the 92 strains, and the presence of 60.8% as four major PFGE clusters unique to Brazil. Another feature was the geographic spread of these clusters over large distances in the country. The city of São Paulo seems to be a Pen-R focus (18.4%) in Brazil. Only two strains representing the international clone B widely spread in France, Portugal, and Spain, belonging to serotype 14, were found.
Assuntos
Resistência às Penicilinas/genética , Streptococcus pneumoniae/efeitos dos fármacos , Brasil , Variação Genética , Testes de Sensibilidade Microbiana , Especificidade da Espécie , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/genéticaRESUMO
During a surveillance study to determine the relative prevalence of capsular types of Streptococcus pneumoniae and antimicrobial susceptibility of invasive isolates in children <5 years old in Mexico City, 220 isolates were collected. The serotype 23F was the most common found, followed by types 6A + B, 14, 19F, and 19A. Diminished susceptibility to penicillin was detected in 106 isolates (48.2%), and high penicillin resistance was found in 49 strains (22.2%), 31 belonging to type 23F. Resistance was also observed to erythromycin (13.1%), to chloramphenicol (43.1%), and to cefotaxime (10.9%). No strains were resistant to ofloxacin or vancomycin. Forty-four of the highly penicillin resistant isolates (penicillin MIC > or =2.0 microg/ml) were examined with molecular fingerprinting techniques; 29 (65.9%) of these isolates (all except two strains) were serotype 23F and shared subtype variants of PFGE type A characteristic of the internationally spread Spanish/USA clone of S. pneumoniae. These strains were also resistant to trimethoprim/sulfametoxasole (TMP/SMX), chloramphenicol, and tetracycline, and most of them were susceptible to erythromycin. Another 6 of the highly penicillin-resistant strains (serogroups 9 and 14) showed PFGE fingerprints and antimicrobial susceptibility pattern characteristic of a second internationally spread clone (French/Spanish clone) and carried resistance to penicillin and TMP/SMX. The rest of the 9 penicillin-resistant isolates were represented by 7 distinct additional PFGE types. The findings suggest that almost 80% of all highly penicillin resistant strains may have been "imported" into Mexico.
Assuntos
Resistência a Múltiplos Medicamentos/genética , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Pré-Escolar , Resistência Microbiana a Medicamentos/genética , Eletroforese em Gel de Campo Pulsado , Humanos , México/epidemiologia , Testes de Sensibilidade Microbiana , Sorotipagem , Infecções Estreptocócicas/epidemiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/genéticaAssuntos
Infecções Pneumocócicas/epidemiologia , Vigilância da População , Streptococcus pneumoniae/classificação , América Central/epidemiologia , Pré-Escolar , Humanos , Lactente , Estudos Multicêntricos como Assunto , Organização Pan-Americana da Saúde , Infecções Pneumocócicas/microbiologia , América do Sul/epidemiologia , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
Streptococcus pneumoniae (SPN) is the most common cause of invasive infections in children, with high levels of mortality in developing countries. An increase in frequency of penicillin-resistant strains is reported in most parts of the world. A study was undertaken in Argentina and 5 other countries of the region, to determine the type distribution and penicillin resistance rate of SPN isolated from invasive infections in children less than 5 years old. Between June 1994 and March 1996, a total of 505 SPN isolated from sterile sites were collected from 15 hospitals located in 9 cities of different geographic areas. Clinical and epidemiological data from 443 children were analyzed. Sixty five percent SPN were isolated from children less than 2 years old. Pneumonia was the clinical diagnosis in 58% of the cases, meningitis in 22%, and sepsis in 10.6%. Isolates were recovered from blood (51.2%), pleural fluid (22.7%), CSF (20.7%), and other sterile sites (5.4%). Thirty different pneumococcal capsular types were identified and the 10 most frequent in descending order were: 14, 5, 1, 6A/6B, 7F, 9V, 19F, 19A, 16F y 23F, representing 89.3% of the total. Overall, 13.1% of isolates showed intermediate resistance to penicillin while 11.3% showed high resistance. Lethality was 8.8%, without correlation with penicillin-resistance and/or type. These result should be used in selecting the optimal combination of specific types for a conjugate vaccine, useful in children less than 2 years old and for considering therapeutic strategies for invasive pneumococcal infections.
Assuntos
Resistência às Penicilinas , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Argentina/epidemiologia , Pré-Escolar , Humanos , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Penicilinas/uso terapêutico , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/etiologia , Infecções Pneumocócicas/mortalidade , Vigilância da População , Fatores de Risco , Sorotipagem , Streptococcus pneumoniae/efeitos dos fármacosRESUMO
A laboratory surveillance study was developed in Brazil in 1993 to determine capsular types and antimicrobial susceptibility of Streptococcus pneumoniae strains. By studying 360 strains isolated from children with invasive infections in three different cities, 8 out of 34 types were identified as being the most prevalent and considered as the reference group for further analyses. This group comprised 77.7% of all strains studied, and includes the types 1, 5, 6A/B, 9V, 14, 19F, 19A, and 23F. The prevalence of this reference group was significantly higher among strains isolated from children with pneumonia than meningitis. Similarly, this group was more prevalent among strains isolated from children 3 to 6 years of age than from children under 2 years of age. Most strains (78.6%) were found to be susceptible to penicillin and only 1.4% showed high resistance to this antibiotic. However, intermediate resistance to penicillin was detected in 20% of the strains. This laboratory surveillance will be maintained and extended to other cities of Brazil to better define and monitor the trends of pneumococcal infections for proper control and prevention.
Assuntos
Resistência Microbiana a Medicamentos , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Brasil/epidemiologia , Criança , Pré-Escolar , Humanos , Lactente , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/epidemiologia , Prevalência , Sorotipagem , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
Streptococcus pneumoniae is the leading bacterial cause of childhood pneumonia in the developing world. This study describes the type distribution and antimicrobial susceptibility of invasive pneumococcal isolates from Colombian children and is part of the Sistema Regional de Vacunas (SIREVA), a PAHO regional initiative designed to determine the ideal serotype composition of a protein polysaccharide pneumococcal conjugate vaccine for use in children less than 5 years old in Latin America. In Colombia, during the study period, centres in Bogota, Medellin, and Cali collected 324 S. pneumoniae isolates from invasive diseases, 238 (73.5%) from children under the age of 2. Pneumonia was the clinical diagnosis in 41.3% cases, meningitis in 41%, and sepsis in 11.2%. The seven most frequent types included 14(21.9%), 5(10.5%), 23F(9.6%), 1(9%), 6B(9%), 19F(7.1%), and 6A(6.2%). The frequency of diminished susceptibility to penicillin (DSP) was 12%, with 8.9% of isolates showing intermediate level resistance and 3.1% showing high level resistance. Among DSP isolates, 23% were also resistant to cefotaxime, 33.3% to erythromycin, 48.7% to chloramphenicol, and 74.3% to trimethoprim/sulfamethoxazole. Multiple resistance was detected in 59% of the isolates that have DSP. Penicillin resistance was associated with types 23F (53.8%) and 14 (25.6%). These data provides information on capsular types prevalent in Colombia that will not only allow the formulation of an ideal vaccine for the region but also reinforce the need for ongoing regional surveillance.
Assuntos
Resistência Microbiana a Medicamentos , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Pré-Escolar , Colômbia/epidemiologia , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/epidemiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , Resultado do TratamentoRESUMO
As part of the Sistema Regional de Vacunas (SIREVA) initiative, we conducted a surveillance study to determine the relative prevalence of capsular types of Streptococcus pneumoniae and antimicrobial susceptibility of invasive isolates in children less than 5 years old. We collected 220 isolates and found 33 of the 90 known types, with type 23F as the most common followed by types 6A+B, 14, 19F, and 19A. High penicillin resistance was found in 49 strains (22.2%), 31 belonging to type 23F. Twenty-nine (13.1%) were resistant to erythromycin, 95 (43.1%) were resistant to chloramphenicol, and 24 (10.9%) were resistant to cefotaxime. No strains were resistant to vancomycin.