Meningitis neumocócica en niños españoles: incidencia, serotipos y resistencia antibiótica. Estudio prospectivo multicéntrico

Paediatric invasive pneumococcal disease on the island of Gran Canaria: 16-year prospective study (2001-2016)

OBJECTIVES

To calculate the incidence of invasive pneumococcal disease (IPD) in the paediatric population of Gran Canaria (Spain), its clinical and epidemiological characteristics, serotype distribution, antibiotic resistance, and variations in these variables before and after the introduction of the PCV13 vaccine.

METHODS

Prospective hospital-based study including all patients (190) aged 0-14 years admitted with confirmed IPD between January 2001-May 2010 (152 cases) and June 2010-December 2016 (38 cases). Patients were divided into 3 age groups (<2 years; 2-5 years; and >5 years). Clinical symptoms were mutually-exclusively classified as meningitis, bacteraemic pneumonia, pleural effusion (PE), empyema or bacteraemia without a focus.

RESULTS

Most cases occurred in boys (59.47%), during autumn-winter (65.79%), in children aged <2 years (55.79%) and with mean age increasing from the pre-PCV13 to the post-PCV13 period (2.5 vs 3.1 years). Incidence between periods reduced by 66.4% (p<0.001): from 13.1/100,000 to 4.4/100,000. PEs (3.9% vs 18.4%, p<0.005) and empyemas (1.5% vs 16.7%, p=NS) increased in the post-PCV13 period whereas all other symptoms decreased, although this was not statistically significant. Vaccine serotypes (77% vs 40.6%, p=0.000), particularly serotypes 19A (23.9% vs 12.5%) and 14 (14.2% vs 9.4%), as well as erythromycin resistance (57.2% vs 7.9%, p=0.000) decreased in the post-PCV13 period.

CONCLUSION

IPD incidence, vaccine serotypes and erythromycin resistance decreased in the post-PCV13 period whereas PEs increased.

Pneumococcal meningitis and vaccine effects in the era of conjugate vaccination: results of 20 years of nationwide surveillance in Germany

Background

Long-term complications and a case mortality rate of 7.5% make meningitis caused by Streptococcus pneumoniae a serious clinical threat. In 2006, a general pneumococcal conjugate vaccination (PCV) recommendation was issued for all children under 2 years in Germany. Here, we investigate serotype changes in meningitis cases after this vaccine recommendation.

Methods

The German National Reference Center for Streptococci (NRCS) has conducted surveillance for invasive pneumococcal disease (IPD) in Germany since 1992. Pneumococcal isolates were serotyped by the Neufeld’s Quellung reaction and antibiotic susceptibility was tested using the broth microdilution method.

Results

Of 22,204 IPD isolates sent to the NRCS from July 1992 to June 2013, 3,086 were meningitis cases. Microbiological and statistical investigations were performed to characterize and quantify all meningitis cases, focusing on changes reflecting implementation of the national PCV recommendation. 1,766 isolates (57.2% of meningitis cases) were from adults (≥16 years) and 1,320 isolates (42.8%) originated from children (<16 years). Overall, the leading serotypes were 14 (9.7%), 7F (7.8%), 3 (6.9%), 19F (5.7%) and 23F (5.0%). Among children, serotypes 14 (16.2%), 7F (8.9%) and 19F (7.1%) were most common, whereas among adults, serotypes 3 (9.6%), 7F (6.9%), 22F (5.0%), 23F (4.9%) and 14 (4.8%) were most prevalent. After the introduction of general PCV7/10/13 vaccination a significant decrease for most vaccine serotypes was observed. Generally, the differences in antibiotic nonsusceptibility between children <16 years and adults ≥16 were low. For macrolides in the pre-PCV7 period, a significantly higher proportion of resistant isolates was found in children (25.1%), compared to the post-vaccination period (9.7%; p<0.0001).

Conclusions

Implementation of the pneumococcal conjugate vaccines broadly reduced vaccine-type meningitis cases. Changes in serotype prevalence must be continuously monitored to observe future trends concerning pneumococcal meningitis.

Treatment and prevention strategies to combat pediatric pneumococcal meningitis

Pneumococcal meningitis is a severe, life-threatening infection of the nervous system affecting infants, children and adults alike. The incidence of pneumococcal meningitis in infants and children less than 2 years of age in Europe is approximately 10 out of 100,000 per year, rising to approximately 148 out of 100,000 per year in Gambian infants. The use of highly sensitive tests such as PCR may increase the likelihood of detecting the infection by 20% or more. Epidemics of serotype 1 pneumococcal meningitis in northern Ghana, have had many of the characteristics of meningococcal meningitis epidemics. Neurologic sequelae may occur in 28-63% of cases, and serotype 3 is associated with a 2.54 relative risk of death. The pathogenic process can be divided into invasion, inflammatory pathways, bacterial toxicity and damage; pneumolysin being particularly associated with apoptosis. In the future, neuroprotection may be achieved, targeting this process at all these levels. Therapeutic guidelines have been published by the Infectious Diseases Society of America. Standard empiric therapy, in those aged greater than or equal to 1 month, is a third-generation cephalosporin plus vancomycin. There is insufficient evidence relating to the use or otherwise of corticosteroids in pneumococcal meningitis to make a firm recommendation. The advent of a pneumococcal conjugate vaccine is the most powerful tool available for the prevention of pneumococcal meningitis in all parts of the world.

[Treatment of pneumococcal meningitis with dexamethasone]

Our aim was two compare two different dexamethasone administration schedules in pneumococcal meningitis: short course (48h) and long course (96h) treatment. We diagnosed 18 pneumococcal meningitis treated with the two different schedules. We found a statistically significant longer duration of primary fever in patients who received dexamethasone for two days. We found no differences in the appearance of secondary fever, or in the development of severe neurological handicaps, or death between the two groups. We conclude that they are no significant differences between the two treatment schedules and that there is a need for developing early prognostic markers and adjuvant therapies that improve the outcome of patients with pneumococcal meningitis.

PCR using blood for diagnosis of invasive pneumococcal disease: systematic review and meta-analysis

The use of molecular-based methods for the diagnosis of bacterial infections in blood is appealing, but they have not yet passed the threshold for clinical practice. A systematic review of prospective and case-control studies assessing the diagnostic utility of PCR directly with blood samples for the diagnosis of invasive pneumococcal disease (IPD) was performed. A broad search was conducted to identify published and unpublished studies. Two reviewers independently extracted the data. Summary estimates for sensitivity and specificity with 95% confidence intervals (CIs) were calculated by using the hierarchical summary receiver operating characteristic method. The effects of sample processing, PCR type, the gene-specific primer, study design, the participants' age, and the source of infection on the diagnostic odds ratios were assessed through meta-regression. Twenty-nine studies published between 1993 and 2009 were included. By using pneumococcal bacteremia for case definition and healthy people or patients with bacteremia caused by other bacteria as controls (22 studies), the summary estimates for sensitivity and specificity were 57.1% (95% CI, 45.7 to 67.8%) and 98.6% (95% CI, 96.4 to 99.5%), respectively. When the controls were patients suspected of having IPD without pneumococcal bacteremia (26 studies), the respective values were 66.4% (95% CI, 55.9 to 75.6%) and 87.8% (95% CI, 79.5 to 93.1%). With lower degrees of proof for IPD (any culture or serology result and the clinical impression), the sensitivity of PCR decreased and the specificity increased. All analyses were highly heterogeneous. The use of nested PCR and being a child were associated with low specificity, while the use of a cohort study design was associated with a low sensitivity. The lack of an appropriate reference standard might have caused underestimation of the performance of the PCR. Currently available methods for PCR with blood samples for the diagnosis of IPD lack the sensitivity and specificity necessary for clinical practice.

[Incidence of pneumococcal disease in the autonomous Region of Madrid (1998--2006)]

BACKGROUND AND OBJECTIVE

The availability of antipneumococcal vaccines makes it necessary to go deeply into the knowledge of pneumococcal disease. This study aims at describing the magnitude and incidence of pneumococcal disease in the Region of Madrid from 1998 to 2006.

MATERIAL AND METHOD

Retrospective study of Computerized Hospital Discharge Data registered from 1998 to 2006. Incidence per 100,000 inhabitants and lethality were calculated. Temporal evolution was analyzed.

RESULTS

20,813 cases of pneumococcal disease were registered (annual average incidence 41.87/100,000 inhabitants). Incidence was 40.65 for pneumoniae and 0.77 for meningitis. People over 64 years old (185.04) and under 1 year of age (67.22) showed the highest incidence. Lethality was 10.1% (15.8% for meningitis). Incidence in 2004--2006 was lower than 1998--2000 (before the introduction of conjugate vaccine). Incidence trend has declined slightly.

CONCLUSIONS

The incidence is higher than that shown by other studies. Selected source of data can explain this difference, since our data included suspected cases. However, pneumococcal meningitis incidence is similar to that described by others.

Reduction in pediatric invasive pneumococcal disease in the Basque Country and Navarre, Spain, after introduction of the heptavalent pneumococcal conjugate vaccine

This study evaluated the incidence of invasive pneumococcal disease, identified the causal serotypes, and tracked the evolution of the antibiotic susceptibility of Streptococcus pneumoniae isolates in the regions of the Basque Country and Navarre, Spain, before and after the introduction of the heptavalent pneumococcal conjugate vaccine. The study included all children aged between birth and 5 years diagnosed with bacteremia, meningitis, or bacteremic pneumonia caused by pneumococci. By the second year after introduction of the heptavalent pneumococcal conjugate vaccine, compared with the period 1998-2001, the incidence of invasive disease decreased by 64.3% in children less than 12 months of age, by 39.7% in children less than 24 months of age, and by 37.5% in children less than 60 months of age. The prevalence of clinical isolates of S. pneumoniae that lacked susceptibility to penicillin decreased by 58.2% among children less than 60 months of age. With an estimated coverage by four-dose heptavalent pneumococcal conjugate vaccine of 28-45% in 2003, the number of invasive pneumococcal infections in the Basque Country and in Navarre fell significantly after just 2 years of immunization, underscoring the importance of improving vaccination coverage under a universal childhood immunization program.

Microbiologic Workload and Clinical Significance ofStreptococcus pneumoniaeIsolated during One Week in Spain

Most studies reporting Streptococcus pneumoniae (Sp) infections select either specific populations/diseases, or refer to a single or a low number of institutions. A nationwide point-prevalence study including 147 hospitals from which we collected all the isolates of Sp reported in a single week (February 16-22, 2004). Workload and clinical data were studied, and susceptibility testing and serotyping of all isolates were performed. The participating institutions had an estimated catchment population of 37,534,750 inhabitants. During the study week, microbiology laboratories received 224,956 samples of which 34,647 were positive and 360 had S. pneumoniae. Overall, 69% of the isolates were from adults (> or = 15 years). Most of the isolates (89%) were considered clinically significant. Infection was community-acquired in 88% of infections and monomicrobial in 79%. We calculated that S. pneumoniae was isolated 38 times per 100,000 inhabitants/year and it was present in 1% of all samples with one or more bacterial isolates. We also calculated that pneumococcal disease (invasive and noninvasive) was present in 34 patients per 100,000 inhabitants/year. Penicillin resistance (I+R) was 42%, and erythromycin resistance was 35%. The most frequent serotypes were 3, 19F, and 19A. Considering only invasive isolates, the estimated coverage of the 7-valent vaccine was 61% in children and 41% in adults, and the estimated coverage of the 23-valent vaccine in adults was 79%. A nationwide point-prevalence study is an efficient tool for surveying pneumococcal infection in a large population.

Invasive pneumococcal disease among children in a health district of Barcelona: early impact of pneumococcal conjugate vaccine

This study evaluated the impact of heptavalent pneumococcal conjugate vaccine (HPCV) on invasive pneumococcal disease (IPD) in children aged < or = 5 years in Barcelona, Spain. The incidence of IPD, vaccine uptake and prevalence of nasopharyngeal colonisation were analysed in two different periods: 1999-2001 (pre-licence period), and 2002-2004 (post-licence period). In total, 121 cases of IPD were identified. The overall incidence of IPD decreased from 96.9 cases/100,000 to 90.6 cases/100,000 (OR 0.93, 95% CI 0.69-1.26, p 0.71) between the two periods. The proportion of cases caused by non-vaccine-related serotypes (NVS) increased from 21% to 43.7% (OR 2.9, 95% CI 1.2-7, p 0.01). IPD was diagnosed in seven vaccinated children, six of whom were infected by NVS. There was a trend of diminishing prevalence of resistance to penicillin and macrolides in 2002-2004. The incidence of empyema increased from 1.7 to 8.5/100,000 (OR 4.5, 95% CI 0.91-18, p 0.06). The rate of vaccination ranged from 4.8% to 34%. It was concluded that the rates of IPD in this area did not decrease following the introduction of HPCV. The low uptake of vaccine and the greater proportion of colonisation/infection by NVS probably explain these findings. A trend of increasing empyema was also apparent. A decrease in the prevalence of penicillin and macrolide resistance paralleled the progressive uptake of vaccine.

Burden of paediatric invasive pneumococcal disease in Europe, 2005

Within the European Union (EU), documenting the burden of invasive pneumococcal disease (IPD) in infants and children is important for coordinating effective pneumococcal immunization policies. Our objective was to document the burden of IPD in countries of the EU plus Switzerland and Norway. European affiliates of Wyeth Vaccines made available recent epidemiological data on IPD from local disease surveillance programmes, including unpublished sources. Recent literature and websites were also searched to provide as wide a representation as possible. This included OVID and abstracts from a number of international meetings, dating from the year 2000. The reported rates of paediatric IPD per 100000 (age) ranged from a low of 1.7 (<2 years) to 4.2 (2-15 years) in Sweden to a high of 93.5 to 174 (<2 years) to 56.2 (<5 years) in Spain. The percentage of circulating serotypes causing IPD that are covered by 7-valent pneumococcal conjugate vaccine (PCV) IPD serotype coverage ranged from 60% to 80% for European children aged <2 years. Under reporting, differences in reporting methods, antibiotic prescribing and disparities in blood-culturing practices may explain the differences in reported disease incidence. Because of the excellent clinical efficacy of the PCV against IPD, national pneumococcal vaccination programmes in Europe have the potential to prevent much morbidity and mortality.

Streptococcus pneumoniae in western Europe: serotype distribution and incidence in children less than 2 years old

We did a systematic search and synthesis of evidence on the incidence of invasive pneumococcal disease, symptomatic disease, and circulating Streptococcus pneumoniae serotypes in western Europe. Using data from studies published between 1992 and 2005 we calculated a weighted mean invasive pneumococcal disease and pneumococcal meningitis incidence rate per 100,000 children aged 2 years or younger within 95% confidence intervals, together with the prevalence of S. pneumoniae serotypes and resistance to penicillin. Invasive pneumococcal disease incidence was 27.03 cases per 100,000 children under 2 years (95% CI 21.85-33.43) [corrected] Heptavalent conjugate vaccine serotypes account for 43.18-75.32% of isolates among people aged under 18 years of age. 11% of isolates in individuals aged under 18 years were penicillin resistant. The incidence of invasive pneumococcal disease appeared consistently lower in western European countries compared with studies from the USA. Thus the use of studies of vaccine effectiveness based on the US population may lead to an overestimation of the benefits of its introduction in Europe.

Clinical data and factors associated with poor outcome in pneumococcal meningitis

We carried out a 4-year study of 159 children (ages 1 month-14 years) with pneumococcal meningitis. The study was divided into two periods: the retrospective period (1998-2000: 107 patients), and the prospective period (2001-2002: 52 patients). About 2/3 of the children were under 2 years of age: 72 (45%) were under 1 year of age and 38 (24%) had meningitis during the second year of life. One-third of the patients had signs of otitis media; convulsions were more frequent in patients under 1 year compared with older patients (34.7 vs. 14.9%; P=0.004); 13/159 children (8.2%) died; 93/159 (58.5%) recovered completely, 12.6% had motor sequelae, 6.9% hydrocephalus, 29.8% sensorineural hearing loss; 140/159 (88%) were treated with third generation cephalosporins, yet only 8.7% of the pneumococci identified were completely penicillin-resistant (> or =1 microg/ml); 119/159 were treated with dexamethasone. Four patients had received an injection of heptavalent vaccine. Antibiotics for 1 week prior to admission, shock, abnormal pupils, leukocytes count <6,000 mm(3), and CSF glucose < or =8.5 mg/dl were significantly associated with poor outcome and/or death in the univariate analysis. No patient with leukocytosis >16,000/mm(3) died. Conclusion. Sequelae are very common in pneumococcal meningitis. Poor outcome was associated with pupillary abnormality and a leukocyte count <6,000/mm(3) on admission. Leukocytosis was protective against poor outcome.

Calendario vacunal de la Asociación Española de Pediatría: recomendaciones 2004

The Vaccine Assessment Committee of the Spanish Association of Pediatrics discusses vaccine developments in 2003 and recommends some modifications to the vaccination schedule. The recommendation of substituting the oral polio vaccine for the inactivated polio vaccine, suppressing the fifth dose, is maintained. The introduction of the conjugate pneumococcal vaccine and the varicella vaccine is stressed. Concerning the meningococcal C vaccine, the improvement introduced by being able to immunize with just two doses is discussed. In agreement with the information received from the European Medicines Agency, there appear to be no well-founded reasons to abandon hexavalent preparations.

Enfermedad invasiva por Streptococcus pneumoniae y Haemophilus influenzae serotipo b. Estudio retrospectivo de 12 años

BACKGROUND

Streptococcus pneumoniae and Haemophilus influenzae serotype b (Hib) are two of the most common causes of invasive bacterial disease in children. The introduction of a successful Hib vaccine and the emergence of penicillin-resistant pneumococci have changed the epidemiology of these bacteria over the last few years.

OBJECTIVES

To evaluate the incidence of S. pneumoniae and Hib invasive disease in children (0-15 years) admitted to our hospital during a 12-year period (January 1991-December 2002).

METHODS

We retrospectively reviewed the medical records of 101 children with isolation of S. pneumoniae and Hib in blood, cerebrospinal fluid (CSF) or synovial fluid samples during the study period.

RESULTS

SP was isolated in 81 samples (72 in blood and nine in CSF) from 73 children (72.6 % were aged < 2 years). The annual incidence per 100,000 children aged 0-2 years was 53.76 cases (95 % CI: 40.7-70.9). The most common clinical diagnosis was bacteremia (67 %). The percentage of penicillin-resistant strains was 44 %. Hib was isolated in 38 samples (26 in blood, 10 in CSF and two in synovial fluid) from 28 children (82.1 % were aged < 2 years). The most common clinical diagnosis was meningitis (35.7 %). The annual incidence per 100,000 children aged between 0-5 years dropped from 21.52 cases (95 % CI: 14.4-32) to 1.7 cases (95 % CI: 0.1-10.8) after systematic vaccination. The percentage of ampicillin-resistant strains was 63.1 %.

CONCLUSIONS

The incidence of invasive pneumococcal disease and the increased antimicrobial resistance rates of pneumococcus are two major reasons to support the routine use of pneumococcal conjugate vaccination in children. Systematic Hib vaccination since October 1998 has dramatically reduced the incidence of this disease.

Incidencia de enfermedad neumocócica invasiva en Cantabria (1995-2001) e implicaciones para el calendario vacunal

OBJECTIVE

To describe the incidence of invasive pneumococcal disease in Cantabria (Spain) between 1995 and 2001.

METHOD

We reviewed the records of the Minimum Data Set (MDS) of public hospitals in Cantabria, discharges from private hospitals and the registry of diseases of mandatory reporting, as well as the microbiologic diagnoses and medical records of children discharged from the Pediatric Service of the Cantabria Hospital (the tertiary care hospital in our autonomous community).

RESULTS

We obtained a meningitis incidence of 5.55, 5.03 and 0.76/100,000 in children < 2 years, > or = 2 and < 5 years, and > or = 5 years respectively, and an incidence of invasive disease of 11.11, 11.32 and 1.49/100,000 in the same age groups.

CONCLUSIONS

The incidence of meningitis and invasive pneumococcal disease in Cantabria is low. We discuss factors that should be taken into account when introducing the pneumococcal conjugate vaccine in the childhood immunization schedule of Cantabria.