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A Ortqvist

Publications and source records attributed to A Ortqvist.

At least 19 recordsLinked to original sources
PubMed2006

Non-response to specific serotypes likely cause for failure to 23-valent pneumococcal polysaccharide vaccine in the elderly.

During a randomised controlled trial with the 23-valent pneumococcal vaccine in older persons, antibody concentrations and opsonophagocytic activity (OPA) were compared between eight patients who developed culture-verified pneumococcal pneumonia and 38 controls, matched for age, sex and vaccination status. Patients who developed pneumococcal pneumonia did not respond with a significant increase of antibody concentration (>1microg/ml) post-vaccination to the infecting serotype, but responded equally well as controls to most other serotypes. Neither was there any significant difference in the OPA post-vaccination between patients and controls. In conclusion, the 23-valent pneumococcal vaccine should be regarded as 23 different vaccines, rather than one. Older persons who fail to respond to one serotype may well be protected against infection by the other 22 serotypes.

Age Factors↗
PubMed2006

Prognostic score systems and community-acquired bacteraemic pneumococcal pneumonia.

The aim of this study was to evaluate the accuracy of three score systems: the pneumonia severity index (PSI); CURB-65 (confusion; urea >7 mM; respiratory rate > or =30 breaths x min(-1); blood pressure <90 mmHg systolic or < or =60 mmHg diastolic; aged > or =65 yrs old); and modified American Thoracic Society rule for predicting intensive care unit (ICU) need and mortality due to bacteraemic pneumococcal pneumonia. All adult patients (n = 114) with invasive pneumococcal pneumonia at the Karolinska University Hospital, Sweden, 1999-2000, were included in the study. Severity scores were calculated and the independent prognostic importance of different variables was analysed by multiple regression analyses. PSI > or = IV, CURB-65 > or = 2, and the presence of one major or more than one minor risk factor in mATS all had a high sensitivity, but somewhat lower specificity for predicting death and ICU need. The death rate was 12% (13 out of 114). Severity score and treatment in departments other than the Dept of Infectious Diseases were the only factors independently correlated to death. Patients treated in other departments more often had severe underlying illnesses and were more severely ill on admission. However, a significant difference in death rates remained after adjustment for severity between the two groups. In conclusion, all score systems were useful for predicting the need for intensive care unit treatment and death due to bacteremic pneumococcal pneumonia. The pneumonia severity index was the most sensitive, but CURB-65 was easier to use.

Adolescent↗
PubMed2006

Clonal and capsular types decide whether pneumococci will act as a primary or opportunistic pathogen.

BACKGROUND: Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. The role of the different capsular and clonal types in invasive disease severity remains to be defined. METHODS: Disease severity and disease type were correlated to age, underlying disease, capsular serotype, and clonal type of the causative agent for 494 adult patients with invasive pneumococcal disease. RESULTS: Pneumococcal isolates of serotypes 1 and 7F were genetically homogenous, had the highest potential to infect previously healthy individuals, and were not causing deaths. Also, type 1 isolates were only found among younger adults, whereas other serotypes were mainly found among elderly persons (e.g., type 23F). Some serotypes and/or clones were more prone to cause more-severe disease, as observed by high APACHE II scores calculated at admission, and were also associated with a high mortality (e.g., clones of type 3 and 11A). We found no evidence of an impact of penicillin resistance on disease severity and disease type. CONCLUSIONS: We suggest that clones with capsular types 1 and 7F, which are known to have a high invasive disease potential, behave as primary pathogens, whereas clones with other capsular types with a lower relative risk of causing invasive disease are more opportunistic, primarily affecting patients with underlying disease. Disease caused by the latter group, however, was more severe, even in previously healthy individuals.

Adult↗
PubMed2006

Addition of a macrolide to a ss-lactam in bacteremic pneumococcal pneumonia.

In the study presented here, data collected prospectively from 340 adult patients hospitalised in five countries with bacteremic pneumococcal CAP and treated with a ss-lactam +/- a macrolide were analysed retrospectively to evaluate the efficacy of this antimicrobial combination. Univariate and multivariate analyses revealed no significant effect on case fatality rate when a macrolide/ss-lactam regimen was used as initial therapy. Results were not affected by severity of illness, or by excluding patients who died within 2 days of admission. Identified predictors of death in a multivariate regression model were age >65 years (OR=2.6), two or more lung lobes affected (OR=2.2), and severity of disease as estimated using the acute physiology score (APS)>8.

Adult↗
PubMed2006

Endocarditis and pericarditis complicating pneumococcal bacteraemia, with special reference to the adhesive abilities of pneumococci: results from a prospective study.

The incidence of pneumococcal cardiac infections is unknown and the pathogenicity of such complications is poorly understood. In a prospective, international, observational study, eight of 844 patients hospitalised with Streptococcus pneumoniae bacteraemia developed endocarditis (n = 5) or pericarditis (n = 3). The clinical and microbiological characteristics of these patients were compared with those of control patients. The corresponding incidence of pneumococcal endocarditis was c. 1-3/1 million inhabitants/year. There was no common pattern in the medical history of patients with an infectious cardiac complication. The severity of illness upon admission was comparable with that for patients without infectious cardiac complications, as was the 14-day mortality rate (25% and 17%, respectively). For encapsulated S. pneumoniae, no significant differences were found between patients with infectious cardiac complications and controls in adherence assays. However, non-encapsulated S. pneumoniae showed higher hydrophobicity and increased adherence to human epithelial cells.

Adolescent↗
PubMed2004

Additive preventive effect of influenza and pneumococcal vaccines in elderly persons.

In 1999, all individuals > or = 65 yrs of age (n=258,754) in Stockholm County, Sweden, were offered influenza and pneumococcal vaccination in a prospective study on the effectiveness of these vaccines in reducing the need for hospital treatment and death due to influenza, pneumonia and invasive pneumococcal disease (IPD). Data on hospitalisation and mortality during 1 yr were obtained from the administrative database in Stockholm County Council. Vaccination was performed in 124,702 (48%) subjects; 72,107 had both vaccines, 29,346 only had the influenza vaccine and 23,249 only had the pneumococcal vaccine. Compared with the unvaccinated cohort, a lower incidence of hospitalisation for all endpoint diagnoses was seen in vaccinated persons. An additive effectiveness of vaccination was seen when both vaccines were given, with a reduction of hospital admissions for influenza (37%), pneumonia (29%) and IPD (44%). In-hospital mortality for pneumonia was significantly lower in those who received both vaccines, than in unvaccinated persons. To conclude, vaccination with influenza and pneumococcal vaccines together was effective in reducing the need for hospital admission for influenza and pneumonia. There was a strong indication that pneumococcal vaccination alone, was effective not only in the prevention of invasive pneumococcal disease, but also of pneumonia overall, although to a low degree.

Aged↗
PubMed2003

Effects of a large-scale intervention with influenza and 23-valent pneumococcal vaccines in elderly people: a 1-year follow-up.

To assess the effectiveness of influenza and pneumococcal vaccination in reducing hospitalisation and deaths in elderly people, the population aged > or =65 years in Stockholm County, Sweden (n = 259627) were invited to take part in a vaccination campaign with influenza and 23-valent pneumococcal vaccine (PV). A no. of persons (100,242) (vaccinated cohort) were vaccinated with one or both vaccines during the campaign. The incidence of hospital admissions during 1 year after the vaccination campaign, adjusted for sex and age, was significantly lower in the vaccinated than in the unvaccinated cohort for influenza (relative risk [RR] 0.68), pneumonia (RR 0.78), and invasive pneumococcal disease (RR 0.46). In the vaccinated cohort, the in-hospital mortality was lower for pneumonia (RR 0.55), COPD (RR 0.53) and cardiac failure (RR 0.72).

Aged↗
PubMed2002

Treatment of community-acquired lower respiratory tract infections in adults.

Community-acquired lower respiratory tract infection (LRTI) is a common cause of acute illness in adults. The spectrum of disease ranges from a mild mucosal colonisation or infection, acute bronchitis or acute exacerbation of chronic bronchitis/chronic obstructive pulmonary disease (AE-CB/COPD), to an overwhelming parenchymal infection with the patient presenting with severe community-acquired pneumonia (CAP). Although the great majority of LRTIs are self-limiting viral infections, CAP is most often a bacterial disease with a substantial mortality. Thus, antibiotic treatment is rarely indicated for acute bronchitis and is only indicated for the more severe cases of AE-CB/COPD, but it is nearly always indicated for CAP, for which a delay in treatment may increase the risk of a fatal outcome. It may be difficult to differentiate between a viral and a bacterial LRTI, or between bronchitis/AE-CB/COPD and CAP. This may be one reason why antibiotics are prescribed to more than two-thirds of patients with LRTIs in Europe and the USA. Considering the worldwide development of antibiotic resistance, this is not an acceptable situation. Since an empirical approach is nearly always necessary in the management of LRTI, greater emphasis must be placed on the decision of whether or not to prescribe an antibiotic at all. This decision should be based on an assessment of the severity of the disease, including underlying risk factors, and on markers for bacterial/parenchymal/ invasive LRTI. The choice of empirical therapy must be based on the same data together with epidemiological information. The choice of antibiotic must always cover Streptococcus pneumoniae, which remains the main pathogen of morbidity and mortality in CAP. In hospital, attempts should be made to obtain an aetiological diagnosis in order to be able to switch to a specific treatment or to evaluate a failure of empirical therapy. Several guidelines for the management of community-acquired pneumonia have been published during the last 10 yrs. Some reports indicate that the implementation of such guidelines has resulted in lowered costs, length of stay in hospital and mortality. However, the results from these studies are not consistent and the evidence is still weak.

Adult↗
PubMed2001

Negligible adjuvant effect for antibody responses and frequent adverse events associated with IL-12 treatment in humans vaccinated with pneumococcal polysaccharide.

To assess whether co-administration of recombinant human IL-12 (rhIL-12) and 23-valent pneumococcal polysaccharide vaccine (PPV) enhances the antibody response to this T cell-independent antigen, healthy immunocompetent volunteers (n=34, 55-65 years old) were vaccinated intramusculary with PPV and concurrently-treated subcutaneously with either rhIL-12 (1 or 4 microg) or placebo. The increases of total anti-pneumococcal IgG antibodies were numerically higher among the rhIL-12 recipients compared with placebo recipients, but the difference was not significant. The rhIL-12 recipients had a high incidence of local and systemic side effects. Given the lack of convincing evidence that rhIL-12 enhances the antibody response to PPV, the frequency and severity of the side effects was unacceptable.

Adjuvants, Immunologic↗
PubMed2001

Dynamics of penicillin-susceptible clones in invasive pneumococcal disease.

In a 10-year period, 1987-1997, there was a >4-fold increase in the rate of pneumococcal bacteremia in Sweden. Invasive pneumococcal isolates (n=1136), which were obtained from 18 Swedish clinical microbiology laboratories from 1987 through 1997, and other national and international isolates were serotyped, and their clonal relationships were determined by molecular typing. The increase in invasive pneumococcal disease in Sweden during this period was associated particularly with an increase in isolates of serotypes 1 and 14. A 3-fold increase of type 14 was seen from 1987 through 1992, and a 10-fold increase of type 1 occurred from 1992 through 1997. One dominating penicillin-susceptible clone of type 14 was responsible for the increase of type 14 during the first 5 years. This clone also was found in Canada and the United States and was shown by multilocus sequence typing to correspond to a previously identified hyper-virulent clone. A novel penicillin-susceptible clone of type 1, which was not found among invasive isolates from 1987 or 1992, was responsible for the increase of serotype 1 during the last 5 years. These results illustrate the ability of virulent penicillin-susceptible pneumococcal clones to emerge and spread rapidly within a country.

Alleles↗
PubMed2001

Effects of a large-scale intervention with influenza and 23-valent pneumococcal vaccines in adults aged 65 years or older: a prospective study.

BACKGROUND: The effectiveness of influenza and pneumococcal vaccination in the prevention of hospital admissions and death has not been assessed prospectively. We have therefore examined the effects of influenza and pneumococcal vaccination in individuals aged 65 years and older in a 3-year prospective study, between Dec 1, 1998 and May 31, 1999. METHODS: All individuals in Stockholm County aged 65 years or older (259,627) were invited to take part in a vaccination campaign against influenza and pneumococcal infection. We recorded for all vaccine recipients (100,242) name, and date of birth, and whether they had been given both or one of the vaccines. All individuals (> or = 65 years) admitted to hospital in Stockholm County with influenza and pneumonia related diagnoses were identified between Dec 1, 1998, and May 31, 1999. FINDINGS: The incidence (per 100,000 inhabitants per year) of hospital treatment was lower in the vaccinated than in the unvaccinated cohort for all diagnoses: 263 versus 484 (-46% [95% CI 34-56]) for influenza; 2199 versus 3097 (-29% [24-34)) for pneumonia; 64 versus 100 (-36% [3-58]) for pneumococcal pneumonia; and 20 versus 40 (-52% [1-77]) for invasive pneumococcal disease. The total mortality was 57% (55-60) lower in vaccinated than in unvaccinated individuals (15.1 vs 34.7 deaths per 1000 inhabitants). INTERPRETATION: These findings show that general vaccination leads to substantial health benefits and to a reduction of mortality from all causes in this age group.

Aged↗
PubMed2001

Clinical isolates of Streptococcus pneumoniae that exhibit tolerance of vancomycin.

The ability of Streptococcus pneumoniae to escape lysis and killing by vancomycin, a property termed "tolerance," has recently been noted in a laboratory strain of the species. Vancomycin tolerance in clinical isolates represents a potential new health risk. We determined the prevalence of vancomycin and penicillin tolerance among 116 clinical isolates of pneumococci by monitoring lysis and viability after exposure to the respective antibiotic for 4 hours. Eight percent of the strains were tolerant to penicillin and 3% were tolerant to vancomycin. The 3 vancomycin-tolerant isolates also had a high ratio of minimum bactericidal concentration to minimum inhibitory concentration, in contrast to nontolerant strains. They were of serotype 9V and had reduced susceptibility to penicillin. Only 1 was also tolerant to penicillin. Growth rate and ability to divide were not affected in the 3 vancomycin-tolerant strains, and they all lysed with deoxycholate, which indicates autolysin production. Vancomycin tolerance among clinical isolates of pneumococci will necessitate tracking to determine the magnitude of the evolving health risk, since tolerance may contribute to treatment failure (in particular, cases of meningitis, in which bactericidal activity is critical for eradication) and since it may also be a favored background for acquisition of resistance of vancomycin.

Amino Acid Sequence↗
PubMed2001

Changes in serotype distribution may hamper efficacy of pneumococcal conjugate vaccines in children.

During the last 10 y we have observed an increased incidence of pneumococcal bacteremia in Sweden. In order to study the serotype distribution over time we collected 1136 invasive pneumococcal isolates from 1987, 1992 and 1997 from Swedish microbiological laboratories. Currently, new pneumococcal conjugate vaccines are being considered for introduction in the general childhood vaccination program in several countries, including Sweden. We studied the potential vaccine coverage rate for the new conjugate vaccines among our Swedish invasive isolates. We found that the serotype distribution fluctuated with time and observed a surprisingly low potential coverage rate for the 7-valent vaccine in Sweden, in contrast to other countries. Therefore we argue that pneumococcal conjugate vaccines have to be tailored to suit current, local serotype patterns and most likely will need to be changed over time.

Adolescent↗
PubMed2001

Pneumococcal vaccination: current and future issues.

Infection with Streptococcus pneumoniae remains a major global health burden meaning the development of effective vaccines is urgently needed. The current 23-valent polysaccharide vaccine has been shown to prevent pneumococcal pneumonia in immunocompetent young adults, but not in elderly persons. However, in prevention of invasive pneumococcal disease, the vaccine is efficacious in the elderly and may also be effective in some groups of immunocompromised patients. The polysaccharide vaccine is, therefore, recommended in all older (> or = 55-65 yrs of age) adults and in young children (>2 yrs of age) who have a high risk for pneumococcal disease. Revaccination can be safely performed and is recommended 5 yrs after the first dose. In children <2 yrs of age, the new polysaccharide-protein conjugate vaccines, including 7-11 serotypes, seem to be effective in the prevention of invasive disease, severe pneumonia and serotype-specific (and vaccine-related types) otitis media. The low serotype coverage, need for repeated doses, and high price, may decrease the usefulness of the new conjugates. However, the included serotypes correspond to those most often associated with penicillin resistance and vaccination is, therefore, a possible tool in limiting the spread of antibiotic-resistant pneumococci.

Adolescent↗
PubMed2000

[Vaccination of the elderly against pneumococcal disease is cost-efficient. Mass vaccination of all aged 65 and over is recommended].

The pneumococcal vaccine has been shown to be about 70 percent efficacious in preventing invasive pneumococcal disease in elderly persons. In a European multicenter study, pneumococcal vaccination was moderately cost-effective in preventing hospital admission due to invasive pneumococcal disease in persons 65 years of age or above. In Sweden the cost was approximately 300,000 SEK per quality adjusted life years (QALY) gained, but only about 60,000 SEK per QALY in a two-way sensitivity analysis making reasonable assumptions regarding the incidence and mortality of invasive pneumococcal disease in this age group. On the basis of these findings, pneumococcal vaccination should be recommended for all persons 65 years of age or older.

Aged↗
PubMed2000

Cost-effectiveness of pneumococcal vaccination of older people: a study in 5 western European countries.

Pneumococcal vaccination of older persons is thought to be cost-effective in preventing pneumococcal pneumonia, but evidence of clinical protection is uncertain. Because there is better evidence of vaccination effectiveness against invasive pneumococcal disease, we determined the cost-effectiveness of pneumococcal vaccination of persons aged > or =65 years in preventing hospital admission for both invasive pneumococcal disease and pneumococcal pneumonia in 5 western European countries. In the base case analyses, the cost-effectiveness ratios for preventing invasive disease varied from approximately 11,000 to approximately 33,000 European currency units (ecu) per quality-adjusted life year (QALY). Assuming a common incidence (50 cases per 100,000) and mortality rate (20%-40%) for invasive disease, the cost-effectiveness ratios were <12,000 ecu per QALY in all 5 countries. For preventing pneumococcal pneumonia, vaccinating all elderly persons would be highly cost-effective to cost saving. Public health authorities should consider policies for encouraging pneumococcal vaccination for all persons aged > or =65 years.

Aged↗