Pyogenic streptococci of Lancefield groups C and G as pathogens in man.
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Anti-Bacterial Agents↗
Biomedical subjects
A Efstratiou
Publications and source records attributed to A Efstratiou.
Prevalence of antibiotic resistance and serotypes in pneumococci in England and Wales: results of observational surveys in 1990 and 1995.
OBJECTIVE: To assess the prevalence of antibiotic resistance and serotype distribution among pneumococci in England and Wales in 1990 and 1995. DESIGN: Observational surveys in March 1990 and March 1995. During two weeks in each survey period all pneumococci isolated in public health laboratories in England and Wales were collected and assessed for sensitivity to antibiotics and the distribution of serogroups or serotypes. SETTING: The network of public health laboratories throughout England and Wales. SUBJECTS: 1127 individual patient isolates of Streptococcus pneumoniae obtained during the two surveys. MAIN OUTCOME MEASURES: Sensitivity or resistance to a range of antibiotics; serogroup or serotype. RESULTS: The prevalence of intermediate or full resistance to penicillin increased from 1.5% in 1990 to 3.9% in 1995 and resistance to erythromycin increased from 2.8% to 8.6%. About 92% of isolates belonged to serogroups or serotypes included in the currently available pneumococcal vaccine. CONCLUSION: Resistance to penicillin and erythromycin has increased among pneumococci in England and Wales. Continued surveillance to assess further increases in the prevalence of pneumococcal resistance to antibiotics is essential.
Anti-Bacterial Agents↗
Combined percutaneous carotid stenting and coronary angioplasty during acute ischemic neurologic and coronary syndromes.
This study demonstrates the feasibility of percutaneous carotid and coronary intervention in patients with unstable neurologic and coronary syndromes. Further study is warranted to determine the safety and long-term results in a large series of patients.
Aged↗
Pneumococcal meningitis in the North East Thames Region UK: epidemiology and molecular analysis of isolates.
One hundred and fourteen cases of pneumococcal meningitis were identified by prospective laboratory based surveillance during 1990-3 in the North East Thames Region. Higher rates of disease were seen in Asians (2.1/100000) than Caucasians (0.8/100000) (P = 0.002). The incidence of meningitis was higher in children than adults, while mortality rates were highest in adults over the age of 60 (48%). In 72 cases, both blood and CSF were culture positive. Serotyping of 65 isolates collected identified 22 serotypes (and one non-typable) causing disease, the most common being serotype 6 (13 cases) and serotype 14 (11 cases). Overall, 90% of serotype antigens identified were represented in the 23 valent vaccine. Ribotyping of 62 isolates identified 35 different patterns, of which 26 were single types. Different ribotypes were found among isolates of the same serotypes, with the exception of serotype 14, where 9 of 11 isolates had the same ribotype pattern. Four percent of isolates had reduced susceptibility to penicillin, but no high level penicillin resistance was found.
Adolescent↗
High-resolution genotyping elucidates the epidemiology of group A streptococcus outbreaks.
Streptococcus pyogenes strains were genotyped by a combination of molecular methods for high- resolution epidemiologic studies of disease outbreaks. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the emm gene is reported. Alone or in conjunction with other molecular techniques (16S ribotyping, pulsed-field gel electrophoresis, and detection of exotoxin genes), PCR-RFLP could differentiate outbreak-related strains from contemporaneous background strains of the same M serotype. Three outbreaks were studied: pharyngitis in a boarding school (serotype M5), cross-infection in a hospital burn unit (serotype M76), and severe invasive disease in two elderly care homes (serotype R28). It was possible, for example, to identify within serotype R28 a clone with particular potential for invasive disease. In all cases, the four molecular methods yielded complementary results that were hierarchically related. Strains could be assigned to the outbreak or the background in a precise, reproducible, and rapid manner.
Antigens, Bacterial↗
Virulence regulon polymorphism in group A streptococci revealed by long PCR and implications for epidemiological and evolutionary studies.
A method based on long PCR amplification and restriction endonuclease analysis of the virulence regulon was developed for a rapid (2 days), simple differentiation of group A streptococci. The PCR product size varied from 12.3 kb for serotypes M1 (NCTC 8198) and M12 (NCTC 10085) to 7.8 kb for serotype M6 (NCTC 8302). The fragment patterns formed on HaeIII digestion of the products were unique and this allowed the differentiation of each of the M-type strains (M1, M3, M4, M5, M6, M11, M12, M28, M76 and M78) studied. Contemporary M1 isolates all gave the same fragment pattern but differed from the prototype strain (NCTC 8198) in not having a 1.25-kb fragment. Isolates of serotypes M1 and M3 each had similar patterns, an indication of their clonality and global dispersion. In contrast, more than one restriction fragment length polymorphism (RFLP) pattern was detected among clinical isolates of serotypes M5, M6, M12, M4, M(R)28 and M78. Two strains that were M-protein non-typable by serological means were provisionally classified as M6 by comparisons of HaeIII long PCR fragment patterns.
Biological Evolution↗
Screening tests for the presumptive identification of Corynebacterium diphtheriae in a diagnostic laboratory.
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Bacterial Typing Techniques↗
Genetic relatedness within and between serotypes of Streptococcus pneumoniae from the United Kingdom: analysis of multilocus enzyme electrophoresis, pulsed-field gel electrophoresis, and antimicrobial resistance patterns.
A collection of 54 isolates of invasive Streptococcus pneumoniae of serotypes 3 and 14 and serogroups 6, 9, 19, and 23 was investigated. Multilocus enzyme electrophoresis and pulsed-field gel electrophoresis suggested that two clones were represented in the collection, one of serotype 14 isolates, most of which were resistant to erythromycin, and one of serotype 9V isolates, in which resistance to penicillin (MIC, 1 microgram/ml), cefotaxime, and co-trimoxazole was common. Among other isolates there were only a limited correlation between genetic relatedness measured by multilocus enzyme electrophoresis and expression of the same capsule type. However, isolates with highly related pulsed-field gel electrophoresis patterns always shared the same serotype and highly related allele profiles. Calculation of the index of association suggests a freely recombining population structure with epidemic spread of successful clones.
Child↗
Diphtheria immunity in UK blood donors.
Immunity to diphtheria was determined in serum samples from 1000 UK-born blood donors at the North London Blood Transfusion Centre during a three-month period in 1993; 125 women and 125 men were stratified in 10-year age groups, from 20 to 59. A tissue (vero cell)-culture toxin-neutralisation assay was used to measure serum diphtheria antitoxin concentrations. According to internationally accepted definitions (antitoxin < 0.01 IU/mL = susceptibility, 0.01-0.09 IU/mL = basic protection, and > or = 0.1 IU/mL = full protection), 37.6% of donors were susceptible to diphtheria, 31.5% had basic protection, and 30.9% were fully protected. Log-linear modelling of the influence of age and sex on population immunity showed a significant trend (p < 0.001) of decreasing immunity with increasing age: 25.2% of donors aged 20-29 were susceptible compared with 52.8% of those aged 50-59. There was a small sex effect (p = 0.052); similar proportions of men and women were susceptible, but fewer women had full protection. There was no age-sex interaction on immunity (p = 0.454). Our results suggest that booster immunisation of adults is necessary to increase herd immunity of the adult population.
Adult↗
An imported fatal case of diphtheria in Italy.
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Adult↗
Epidemiology and molecular characterisation of toxigenic Corynebacterium diphtheriae var mitis from a case of cutaneous diphtheria in Manchester.
Diphtheria is now an uncommon disease in Britain. We describe an imported case of cutaneous diphtheria in a previously immunised adult cause by C. diphtheriae var mitis. The control measures adopted to deal with the index case and two secondary cases so as to limit further spread among household and school contacts are outlined. Molecular typing was used to study the mode of spread of the organism among contacts.
Adult↗
A cluster of cases of streptococcal necrotizing fasciitis in Gloucestershire.
We describe the first cluster of cases of necrotizing fasciitis (NF) in this century in the United Kingdom (UK). Between 1 January and 30 June 1994 there were six cases (five confirmed, one probable) of Streptococcus pyogenes NF in west Gloucestershire, population 320,000. Two cases died. The first two patients probably acquired their infections during the course of elective surgery performed in the same operating theatre, possibly from a nasopharyngeal carrier amongst the theatre staff. The remaining infections were community-acquired. Of 5 S. pyogenes isolates there were 2 M1 strains, 1 M3, 1 M5 and 1 M non-typeable strain. S. pyogenes NF had not been recorded in west Gloucestershire in the preceding 10 years and the incidence of S. pyogenes bacteraemia in England and Wales had not risen in the past 5 years. The two presumably theatre-acquired infections raised several issues. The need for detailed bacteriological investigation of all cases of post-surgical NF was confirmed. Clusters of S. pyogenes infection following surgery should be managed by closure of the operating theatre until all staff have been screened for carriage. Closure of an operating theatre and screening of staff following a sporadic case is probably not justified because of the infrequency of surgical cross-infection with S. pyogenes. Regular, routine screening of theatre staff is neither practical nor necessary.
Aged↗
Distribution of serovariants of group B streptococci in isolates from England and Norway.
The distribution of capsular polysaccharide antigen (CHO) types, surface-exposed c proteins alpha (c alpha) and beta (c beta) and an R-protein antigen was examined in 334 group B streptococci (GBS) isolates from three groups of patients hospitalised in England and Wales or Norway. The isolates were from 108 carriers, 67 cases of neonatal infection and 154 cases of adult infection. Each group contained all CHO types (Ia, Ib, II, III, IV, V and NT); type III strains predominated except in the adult infected group. Strains within each CHO type could be further subdivided by the protein markers into five subtypes by a combined typing system. The proportion of type Ib and type III strains in the neonatal infection cases and of type Ib strains in the adult infection cases significantly outnumbered isolates of these serotypes among the carrier strains. Twenty-nine different serovariants were identified; 24, 13 and 23 serovariants among the carrier, neonatal infection and adult infection isolates, respectively. Certain CHO antigen-protein associations were identified, notably those between Ia/c alpha, Ib/c alpha beta and III/R. The proportion of invasive isolates that expressed protein was not higher than in the carrier isolates. All CHO-type Ib isolates contained a c protein, but 7% of the Ib isolates did not contain any of these proteins. These findings indicate that this combined typing approach may be useful in examining epidemiological problems associated with GBS.
Adult↗
Molecular subtyping of prevalent M serotypes of Streptococcus pyogenes causing invasive disease.
Reproducible methodologies and a scheme for high-resolution genotyping of Streptococcus pyogenes were defined with respect to a study of six predominant M serotypes causing invasive group A streptococcal disease in the United Kingdom. Serotype reference strains were compared with nine clinical isolates of each serotype from patients with diseases such as pneumonia, puerperal sepsis, toxic shock-like-syndrome, cellulitis, or necrotizing fasciitis. Four enzymes were evaluated for their discriminatory power in 16S rRNA gene-specific ribotyping. Discriminatory power was greatest with EcoRI, which generated serotype-specific ribotypes, and with SacI, which could subdivide strains of the same M serotype. Twenty-five combined ribotypes were found among the 60 strains, and the indices of discriminatory power (D values) of this method varied from 0.51 within serotype M1 to 0.98 within strains of serotype M5. Macrorestriction with the rarely cutting endonuclease SmaI and pulsed-field gel electrophoresis gave D values varying from 0.37 within serotype M1 to the maximal 1.0 within serotype M5. Comparison of macrorestriction profiles revealed various degrees of genetic heterogeneity within M serotypes. Strains of M1, M3, M6, and M11 exhibited clonally related macrorestriction profiles, while those of R28 and M5 strains were consistent with polyphyletic origin.
Antigens, Bacterial↗
Molecular epidemiology of Corynebacterium diphtheriae from northwestern Russia and surrounding countries studied by using ribotyping and pulsed-field gel electrophoresis.
A selection of 100 Corynebacterium diphtheriae isolates from asymptomatic carriers and clinical cases from five regions in northwestern Russia were examined. Six additional isolates from patients in Finland and Estonia with epidemiological links to Russia were also examined. All isolates were characterized by biotyping, toxigenicity testing, ribotyping, and pulsed-field gel electrophoresis (PFGE). Hybridization of genomic DNA digested with BstEII revealed five ribotype patterns among the biotype gravis isolates (G1 through G5) and two patterns among the biotype mitis isolates (M1 and M2). PFGE using SfiI was not able to distinguish between ribotypes G1, G2, and G4. The predominant ribotype pattern, G1, found in cases of disease in all the areas studied, appears to be disseminating, in view of the isolates received from imported cases in Finland and Estonia. Among the 106 isolates examined, 68 produced pattern G1 and 24 produced pattern M1. Most of the M1 isolates were from the Leningrad Oblast region. Distinct ribotypes such as G2, G3, G4, G5, and M2 could represent endemic disease.
Bacterial Typing Techniques↗
Combined spontaneous postpartum coronary artery dissection and pulmonary embolism with survival.
A young woman who survived after suffering in the immediate postpartum period a spontaneous coronary dissection with resultant myocardial infarction and a pulmonary embolism with pulmonary infarct is presented. Diagnostic and therapeutic considerations for this unique occurrence are discussed and reviewed.
Adult↗
An outbreak of group C streptococcal infection in a maternity unit.
An outbreak of Group C streptococcal infection (Streptococcus equisimilis serotype T204) occurred in a Maternity Unit in Durham over a 2-week period. The outbreak strain possessed an M-protein antigen identical to that found in a previously reported Maternity Unit outbreak. Seven patients in total were affected, and in two patients infected perineal wounds took several weeks to heal. The source of the outbreak appeared to be a patient who developed a perineal wound infection and who subsequently returned to the ward for reassessment. Environmental contamination is likely to have been the reservoir of infection for the subsequent patients. The outbreak was controlled by applying strict infection control procedures and establishing a high standard of routine cleaning.
Cross Infection↗
The in-vitro susceptibilities of toxigenic strains of Corynebacterium diphtheriae isolated in northwestern Russia and surrounding areas to ten antibiotics.
The in-vitro activities of ten antibiotics against 83 toxigenic strains of Corynebacterium diphtheriae recently isolated in northwestern Russia and surrounding areas were determined by an agar dilution method. All of the strains were susceptible to erythromycin, penicillin, ampicillin, cefuroxime, chloramphenicol, ciprofloxacin, gentamicin and tetracycline. Trimethoprim and rifampicin were each active against 81 isolates, the two strains resistant to the latter agent having been isolated from two members of the same family.
Anti-Bacterial Agents↗