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Prevalence and Clonal Distribution of pcpA, psrP and Pilus-1 among Pediatric Isolates of Streptococcus pneumoniae  [PDF]
Laura Selva, Pilar Ciruela, Krystle Blanchette, Eva del Amo, Roman Pallares, Carlos J. Orihuela, Carmen Mu?oz-Almagro
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0041587
Abstract: Streptococcus pneumoniae is the leading cause of vaccine-preventable deaths globally. The objective of this study was to determine the distribution and clonal type variability of three potential vaccine antigens: Pneumococcal serine-rich repeat protein (PsrP), Pilus-1, and Pneumococcal choline binding protein A (PcpA) among pneumococcal isolates from children with invasive pneumococcal disease and healthy nasopharyngeal carriers. We studied by Real-Time PCR a total of 458 invasive pneumococcal isolates and 89 nasopharyngeal pneumococcal isolates among children (total = 547 strains) collected in Barcelona, Spain, from January 2004 to July 2010. pcpA, psrP and pilus-1 were detected in 92.8%, 51.7% and 14.4% of invasive isolates and in 92.1%, 48.3% and 18% of carrier isolates, respectively. Within individual serotypes the prevalence of psrP and pilus-1 was highly dependent on the clonal type. pcpA was highly prevalent in all strains with the exception of those belonging to serotype 3 (33.3% in serotype 3 isolates vs. 95.1% in other serotypes; P<.001). psrP was significantly more frequent in those serotypes that are less apt to be detected in carriage than in disease; 58.7% vs. 39.1% P<.001. Antibiotic resistance was associated with the presence of pilus-1 and showed a negative correlation with psrP. These results indicate that PcpA, and subsequently Psrp and Pilus-1 together might be good candidates to be used in a next-generation of multivalent pneumococcal protein vaccine.
Streptococcus pneumoniae Clonal Complex 199: Genetic Diversity and Tissue-Specific Virulence  [PDF]
Jonathan C. Thomas,Marisol Figueira,Kristopher P. Fennie,Alison S. Laufer,Yong Kong,Michael E. Pichichero,Stephen I. Pelton,Melinda M. Pettigrew
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0018649
Abstract: Streptococcus pneumoniae is an important cause of otitis media and invasive disease. Since introduction of the heptavalent pneumococcal conjugate vaccine, there has been an increase in replacement disease due to serotype 19A clonal complex (CC)199 isolates. The goals of this study were to 1) describe genetic diversity among nineteen CC199 isolates from carriage, middle ear, blood, and cerebrospinal fluid, 2) compare CC199 19A (n = 3) and 15B/C (n = 2) isolates in the chinchilla model for pneumococcal disease, and 3) identify accessory genes associated with tissue-specific disease among a larger collection of S. pneumoniae isolates. CC199 isolates were analyzed by comparative genome hybridization. One hundred and twenty-seven genes were variably present. The CC199 phylogeny split into two main clades, one comprised predominantly of carriage isolates and another of disease isolates. Ability to colonize and cause disease did not differ by serotype in the chinchilla model. However, isolates from the disease clade were associated with faster time to bacteremia compared to carriage clade isolates. One 19A isolate exhibited hypervirulence. Twelve tissue-specific genes/regions were identified by correspondence analysis. After screening a diverse collection of 326 isolates, spr0282 was associated with carriage. Four genes/regions, SP0163, SP0463, SPN05002 and RD8a were associated with middle ear isolates. SPN05002 also associated with blood and CSF, while RD8a associated with blood isolates. The hypervirulent isolate's genome was sequenced using the Solexa paired-end sequencing platform and compared to that of a reference serotype 19A isolate, revealing the presence of a novel 20 kb region with sequence similarity to bacteriophage genes. Genetic factors other than serotype may modulate virulence potential in CC199. These studies have implications for the long-term effectiveness of conjugate vaccines. Ideally, future vaccines would target common proteins to effectively reduce carriage and disease in the vaccinated population.
Sequence Analysis of 96 Genomic Regions Identifies Distinct Evolutionary Lineages within CC156, the Largest Streptococcus pneumoniae Clonal Complex in the MLST Database  [PDF]
Monica Moschioni, Morena Lo Sapio, Giovanni Crisafulli, Giulia Torricelli, Silvia Guidotti, Alessandro Muzzi, Michèle A. Barocchi, Claudio Donati
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0061003
Abstract: Multi-Locus Sequence Typing (MLST) of Streptococcus pneumoniae is based on the sequence of seven housekeeping gene fragments. The analysis of MLST allelic profiles by eBURST allows the grouping of genetically related strains into Clonal Complexes (CCs) including those genotypes with a common descent from a predicted ancestor. However, the increasing use of MLST to characterize S. pneumoniae strains has led to the identification of a large number of new Sequence Types (STs) causing the merger of formerly distinct lineages into larger CCs. An example of this is the CC156, displaying a high level of complexity and including strains with allelic profiles differing in all seven of the MLST loci, capsular type and the presence of the Pilus Islet-1 (PI-1). Detailed analysis of the CC156 indicates that the identification of new STs, such as ST4945, induced the merging of formerly distinct clonal complexes. In order to discriminate the strain diversity within CC156, a recently developed typing schema, 96-MLST, was used to analyse 66 strains representative of 41 different STs. Analysis of allelic profiles by hierarchical clustering and a minimum spanning tree identified ten genetically distinct evolutionary lineages. Similar results were obtained by phylogenetic analysis on the concatenated sequences with different methods. The identified lineages are homogenous in capsular type and PI-1 presence. ST4945 strains were unequivocally assigned to one of the lineages. In conclusion, the identification of new STs through an exhaustive analysis of pneumococcal strains from various laboratories has highlighted that potentially unrelated subgroups can be grouped into a single CC by eBURST. The analysis of additional loci, such as those included in the 96-MLST schema, will be necessary to accurately discriminate the clonal evolution of the pneumococcal population.
Susceptibilidad antimicrobiana, serotipos capsulares y relación clonal entre cepas invasoras de Streptococcus pneumoniae aisladas de pacientes adultos de la Región del Bío-Bío, Chile: Período 2005-2006 Antimicrobial susceptibility, capsular serotypes and clonal relationship of invasive Streptococcus pneumoniae isolates in adult population of the Bio-Bio Region, Chile: 2005-2006
Cristian Aguilera R,Gerardo González R,Helia Bello T,Sergio Mella M
Revista chilena de infectología , 2010,
Abstract: Las infecciones ocasionadas por Streptococcus pneumoniae constituyen un problema de salud pública. En nuestro país existe escasa información sobre aislados de procesos bacteriémicos en población adulta. Se estudió la susceptibilidad, serotipos y relación clonal de 56 aislados de S. pneumoniae desde hemocultivos, entre enero 2005 y agosto 2006, de pacientes adultos de la intercomuna Concepción-Talcahuano, Región del Bío-Bío, Chile. Se encontró resistencia a tetraciclina (21,4%), cotrimoxazol (18%), eritromicina (18%), cloranfenicol (7%) y a penicilina en un solo aislado procedente de un foco meníngeo (2 %). La totalidad mostró susceptibilidad a cefotaxima, levofloxacina, moxifloxacina y vancomicina. Se demostró una amplia variedad de serotipos capsulares, con predominio de los serotipos 1, 5, 23F, 7F y 3. El análisis de macrorestricción y electroforesis en campo pulsado reveló 31 patrones electroforéticos con 12 grupos clona-les, descartando un clon predominante. De acuerdo a los resultados, al menos 80% de los serotipos de aislados de S. pneumoniae de procesos bacteriémicos están incluidos en la vacuna comercial disponible. Streptococcus pneumoniae infections constitute a public health problem. In our country there is scarce information regarding isolates from bacteraemic episodes in adult population. The antibiotic susceptibility, sero-types and clonal relationship of 56 isolates of S. pneumoniae from adult patients with bacteraemic infections in Concepcion-Talcahuano, Bio-Bio Region, Chile, were studied. Resistance to tetracycline (21.4%), trimethoprim/ sulfamethoxazole (18%), erythromycin (18%), chloramphenicol (7%) and 1 penicillin resistant isolate from a meningeal focus (2%) was found. Also, all the isolates were susceptible to cefotaxime, levofloxacin, moxifloxacin and vancomycin. A wide variety of capsular serotypes was demonstrated, with predominance of serotypes 1, 5, 23F, 7F and 3. The macrorestriction analysis by pulse field electrophoresis revealed 31 electrophoretic patterns and 12 clonal groups, discarding a predominant clone. According to the results, at least, 80% of the S. pneumoniae serotypes isolated from bacteraemic adult patients are included in the available commercial vaccine.
Susceptibilidad antimicrobiana, serotipos capsulares y relación clonal entre cepas invasoras de Streptococcus pneumoniae aisladas de pacientes adultos de la Región del Bío-Bío, Chile: Período 2005-2006
Aguilera R,Cristian; González R,Gerardo; Bello T,Helia; Mella M,Sergio; Blamey D,Rodrigo; Chabouty G,Henriette; Hormazábal O,Juan C; Maldonado B,Aurora; Rojas U,Bianca; Seoane M,Mabel; Domínguez Y,Mariana;
Revista chilena de infectología , 2010, DOI: 10.4067/S0716-10182010000600002
Abstract: streptococcus pneumoniae infections constitute a public health problem. in our country there is scarce information regarding isolates from bacteraemic episodes in adult population. the antibiotic susceptibility, sero-types and clonal relationship of 56 isolates of s. pneumoniae from adult patients with bacteraemic infections in concepcion-talcahuano, bio-bio region, chile, were studied. resistance to tetracycline (21.4%), trimethoprim/ sulfamethoxazole (18%), erythromycin (18%), chloramphenicol (7%) and 1 penicillin resistant isolate from a meningeal focus (2%) was found. also, all the isolates were susceptible to cefotaxime, levofloxacin, moxifloxacin and vancomycin. a wide variety of capsular serotypes was demonstrated, with predominance of serotypes 1, 5, 23f, 7f and 3. the macrorestriction analysis by pulse field electrophoresis revealed 31 electrophoretic patterns and 12 clonal groups, discarding a predominant clone. according to the results, at least, 80% of the s. pneumoniae serotypes isolated from bacteraemic adult patients are included in the available commercial vaccine.
Resistance of Streptococcus pneumoniae to antimicrobials in S?o Paulo, Brazil: clinical features and serotypes
Levin, Anna Sara S.;Teixeira, Lucia Martins;Sessegolo, Juliana Furian;Barone, Antonio Alci;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1996, DOI: 10.1590/S0036-46651996000300004
Abstract: to study resistance to antimicrobials, serotypes and clinical features of s. pneumoniae in s. paulo, brazil, 50 patients with a positive culture were evaluated: 7 were considered carriers and 43 had pneumococcal infections. pneumonia and meningitis were the most commom infections. mortality was 34% and underlying diseases were present in 70%. relative resistance to penicillin occurred in 24% and complete resistance was not detected. resistance to tetracycline was 32% and to sulfamethoxazole/trimethoprim 32%; one strain had intermediate susceptibility to erythromycin; no resistance was present for chloramphenicol, rifampin or vancomycin. resistance to at least one of the drugs tested occurred in 62%. results by the e-test for penicillin were similar to those by the agar dilution method. there were 24 different serotypes and 74% of the strains belonged to the 23-valent vaccine including all the penicillin-resistant strains. in this study s. pneumoniae caused severe infections and presented a high resistance rate to commonly used antimicrobials. routine surveillance of resistance and the use of vaccination, as well as the restriction of inappropriate use of antimicrobials, are recommended in s?o paulo, brazil.
Seasonality and outbreak of a predominant Streptococcus pneumoniae serotype 1 clone from The Gambia: Expansion of ST217 hypervirulent clonal complex in West Africa
Martin Antonio, Ishrat Hakeem, Timothy Awine, Ousman Secka, Kawsu Sankareh, David Nsekpong, George Lahai, Abiodun Akisanya, Uzochukwu Egere, Godwin Enwere, Syed MA Zaman, Philip C Hill, Tumani Corrah, Felicity Cutts, Brian M Greenwood, Richard A Adegbola
BMC Microbiology , 2008, DOI: 10.1186/1471-2180-8-198
Abstract: A total of 127 invasive and 36 nasopharyngeal carriage serotype 1 isolates were recovered from individuals of all age groups and were analyzed by serotyping, antibiotic susceptibility testing and MLST. MLST analysis revealed 23 different sequence types (STs), 18 of which were novel. The most prevalent clone among the 163 isolates was ST618 (70.5%), followed by ST3575 (7.4%), ST2084 (2.5%) and ST612 (2.5%). A single ST (ST618), previously shown to belong to the ST217 hypervirulent clonal complex, was frequent among carriage (61.1%) and invasive (72.7%) serotype 1 isolates. ST618 causing both paediatric and adult disease peaked annually in the hot dry season and caused outbreak in 1997 and 2002.For over a decade, isolates of ST618 have been the dominant lineage among serotype 1 carriage and disease isolates circulating in the Gambia. This lineage shows similar epidemiological features to those of the meningococcus in the African meningitis belt being able to cause outbreaks of diseaseStreptococcus pneumoniae consists of at least 91 different serotypes, the majority of which rarely cause disease; two serotypes (1 and 5) cause > 30% of invasive disease, among all age groups combined, in The Gambia [1]. Serotype 1 has the potential to cause epidemics – it was recently a cause of outbreaks of meningitis in Burkina Faso and Northern Ghana [2,3]. It has also been associated with outbreaks in crowded or closed communities [4-6]. In contrast, it is only rarely detected in carriage studies [7]. The available, licensed pneumococcal conjugate vaccine (Prevenar?) contains seven of the 91 pneumococcal serotypes and does not contain conjugates of serotypes 1 and 5 [8]. A trial of a 9-valent pneumococcal conjugate vaccine in a rural setting in The Gambia showed protective efficacy against radiological pneumonia (37%) and all invasive pneumococcal disease (50%) and reduced all cause hospitalisations and mortality by 15% and 16% respectively [9]. Although the 9-valent vaccine containe
PENICILLIN–RESISTANT STREPTOCOCCUS PNEUMONIAE – A REVIEW
SS Taiwo, BA Onile
African Journal of Clinical and Experimental Microbiology , 2004,
Abstract: Since the first report in 1967, the incidence of Penicillin Resistant Streptococcus pneumoniae (Pneumococcus) has risen steadily worldwide, and now complicates diagnostic and treatment strategies for infections due to this organism. More worrisome is the fact that in areas where Penicillin Resistant Streptococcus pneumoniae (PRSP) has become established, resistance to other antimicrobial agents such as cephalosporins, sulphonamides and macrolides is also common. This development has a grave implication for therapy of life threatening pneumococcal infections like meningitis and septicaemia, with the extended spectrum cephalosporins, such as ceftriaxone and cefotaxime, and the newer macrolides, azithromycin and clarithromycin. The mechanism of resistance to β-lactam antibiotics is decreased binding of drug to the bacteria cell wall brought about by genetic transformation in bacterial chromosome. Recently, using molecular techniques that can index overall relatedness of the drug resistant pneumococcal isolates, it has been possible to establish clonal dissemination of drug resistant pneumococci across continents, with acquisition of additional drug resistance determinants as a result of “local” antibiotic selective pressures. This is a review of literature on the epidemiology, mechanism of resistance, laboratory identification, treatment, prevention and control of Penicillin Resistant Pneumococci (PRP), with emphasis on the problems of identification and reporting in developing countries. Key Words: penicillin, Streptococcus pneumoniae, resistant, extended spectrum cephalosporins. African Journal Of Clinical And Experimental Microbiology Jan 2004 Vol.5 No.1 78-107
Custos hospitalares da meningite causada por Streptococcus pneumoniae na cidade de S?o José dos Campos, S?o Paulo, Brasil
Lucarevschi, Bianca Rezende;Escobar, Ana Maria de Ulh?a;Grisi, Sandra;
Cadernos de Saúde Pública , 2012, DOI: 10.1590/S0102-311X2012000400013
Abstract: knowledge of hospital costs is highly important for public health decision-making. this study aimed to estimate direct hospital costs related to pneumococcal meningitis in children 13 years or younger in the city of s?o josé dos campos, s?o paulo state, brazil, from january 1999 to december 2008. data were obtained from medical records. hospital costs were calculated according to the mixed method for measurement of quantities of items with identified costs and value attribution to items consumed (micro-costing and gross-costing). all costs were calculated according to monetary values for november 2009 and in brazilian currency (real). epi info 3.5.1 was used for frequencies and means analysis. forty-one cases were reported. direct hospital costs varied from r$ 1,277.90 to r$ 19,887.56 (mean = r$ 5,666.43), or 10 to 20 times the mean cost of hospitalization for other diseases. hospital staff labor was the highest cost, followed by medication, procedures, supplies, and lab tests.
Meningoencefalitis bacteriana a Streptococcus pneumoniae
Estévez Sierra,Ingrid; Sanchén Casas,Alexis; Rodríguez Heredia,Odalys; García González,Gloria;
Revista Archivo M??dico de Camag??ey , 2011,
Abstract: background: the streptococcus pneumoniae occupies the first place among the causal bacteria of bacterial meningoencephalitis since the year 2000, which affects children and adults with great lethality. objective: to characterize some epidemiological and microbiological aspects from the bacterial meningoencephalitis to streptococcus pneumoniae. method: a descriptive and observational study on bacterial meningoencephalitis to streptococcus pneumoniae was performedin the microbiology lab at the provincial center of hygiene epidemiology and microbiology from 2000 to 2009. the universe was constituted by 209 patients with bacterial meningoencephalitis and the sample was formed of 50 positive patients to streptococcus pneumoniae. results: the 24,4 % of patients had streptococcus pneumoniae. all the ages were affected, especially the old men with lethality of 80 %. there was 40% of deaths in children and 60 % in adults. the bacteriological study of the cerebrospinal fluid turned out to be the most important test to establish the bacterial meningoencephalitis diagnostic to streptococcus pneumoniae. the 84% of strains was detected to be resistant to penicillin. conclusions: results demonstrate that an extreme surveillance should be carried to the meningoencephalitis to this germ in vulnerable population in the face of the great lethality observed in the positive patients to streptococcus pneumoniae.
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