Risk factors for 30-day mortality in adult patients with pneumococcal bacteraemia, and the impact of antimicrobial resistance on clinical outcomes

A historical perspective of MDR invasive pneumococcal disease in Spanish adults

OBJECTIVES

To analyse the clonal dynamics and clinical characteristics of adult invasive pneumococcal disease (IPD) caused by MDR and penicillin-non-susceptible (PNS) pneumococci in Spain.

METHODS

All adult IPD episodes were prospectively collected (1994-2018). Streptococcus pneumoniae isolates were serotyped, genotyped and tested for antimicrobial susceptibility. Changes in the incidence of IPD were analysed and risk factors contributing to MDR were assessed by logistic regression.

RESULTS

Of 2095 IPD episodes, 635 (30.3%) were caused by MDR/PNS isolates. Over the study period, the incidence of MDR/PNS-IPD decreased (IRR 0.70; 95% CI 0.53-0.93) whereas that of susceptible isolates remained stable (IRR 0.96; 95% CI 0.80-1.16). A reduction of resistance rates to penicillin (-19.5%; 95% CI -37% to 2%) and cefotaxime (-44.5%; 95% CI -64% to -15%) was observed. Two clones, Spain9V-ST156 and Denmark14-ST230, accounted for 50% of current resistant disease. Among current MDR/PNS isolates, 45.8% expressed serotypes not covered by the upcoming PCV15/PCV20 vaccines. MDR/PNS episodes were associated with older patients with comorbidities, nosocomial acquisition and higher 30 day mortality. MDR/PNS pneumococci were not independently associated with 30 day mortality in multivariate analysis [OR 0.826 (0.648-1.054)].

CONCLUSIONS

Our study shows an overall reduction of MDR/PNS isolates in adults after the introduction of pneumococcal conjugate vaccines. However, a significant proportion of current resistant isolates are not covered by any of the upcoming PCV15/PCV20 vaccines. The burden of resistant disease is related to older patients with underlying conditions and caused by two major clones. Our data show that MDR is not a statistically significant factor related to increased mortality.

Prognostic factors for mortality in invasive pneumococcal disease in adult: a system review and meta-analysis

Risk factors associated with mortality in invasive pneumococcal disease remain unclear. The present work is a meta-analysis of studies that enrolled only patients with invasive pneumococcal disease and reported on mortality. Potentially eligible reports were identified from PubMed, CHAHL, and Web of Science, comprising 26 reports in total. Overall mortality for invasive pneumococcal disease was reported as 20.8% (95% confidence interval (CI) 17.5–24%). Factors associated with mortality were age (odds ratio (OR) 3.04, 95% CI 2.5–3.68), nursing home (OR 1.62, 95% CI 1.13–2.32), nosocomial infection (OR 2.10, 95% CI 1.52–2.89), septic shock (OR 13.35, 95% CI 4.54–39.31), underlying chronic diseases (OR 2.34, 95% CI 1.78–3.09), solid organ tumor (OR 5.34, 95% CI 2.07–13.74), immunosuppressed status (OR 1.67, 95% CI 1.31–2.14), and alcohol abuse (OR 3.14, 95% CI 2.13–4.64). Mortality rates with invasive pneumococcal disease remained high, and these findings may help clinicians provide appropriate initial treatment for this disease.

Factors Associated With Severe Nonmeningitis Invasive Pneumococcal Disease in Adults in France

Background

In France, pneumococcal vaccination in adults is recommended for risk groups (chronic conditions/immunosuppression). We conducted a study on invasive pneumococcal disease (IPD) in adults to identify factors associated with disease severity and death.

Methods

We included IPD cases, excluding meningitis, from 25 acute care hospitals in 6 regions. We defined severe cases as those with shock or severe sepsis or intensive care unit admission/mechanical ventilation. We included deaths occurring within 30 days of hospitalization. Infectious disease specialists collected clinical/microbiological data on cases.

Results

During 2014–2017, 908 nonmeningitis IPD cases were diagnosed; 48% were severe, 84% had comorbidities, 21% died. Ninety percent of cases with comorbidities who previously sought health care were not vaccinated against pneumococcus. Compared with previously healthy cases, the risk of severe IPD increased from 20% (adjusted risk ratio [aRR], 1.2; 95% confidence interval [CI], 1.0–1.4) in cases with 1–2 chronic diseases to 30% (aRR, 1.3; 95% CI, 1.0–7.0) in those with >2 chronic diseases. Among risk groups, 13-valent pneumococcal conjugate vaccine (PCV13) serotypes and 23-valent pneumococcal polysaccharide vaccine (PPSV23) nonPCV13 serotypes were more likely to induce severe IPD compared with nonvaccine serotypes (aRR, 1.5; 95% CI, 1.3–1.9; aRR, 1.3; 95% CI, 1.0–1.5, respectively).

Conclusions

We observed a cumulative effect of concurrent comorbidities on severe IPD. Vaccine serotypes were more likely to induce severe IPD among risk groups. The missed opportunities for vaccination underscore the need to enhance vaccination in risk groups.

Impact of Cefotaxime Non-susceptibility on the Clinical Outcomes of Bacteremic Pneumococcal Pneumonia

Background: We aimed to analyze the impact of cefotaxime non-susceptibility on the 30-day mortality rate in patients receiving a third-generation cephalosporin for pneumococcal bacteremic pneumonia. Methods: We conducted a retrospective observational study of prospectively collected data from the Hospital Clinic of Barcelona. All adult patients with monomicrobial bacteremic pneumonia due to Streptococcus pneumoniae and treated with a third-generation cephalosporin from January 1991 to December 2016 were included. Risk factors associated with 30-day mortality were evaluated by univariate and multivariate analyses. Results: During the study period, 721 eligible episodes were identified, and data on the susceptibility to cefotaxime was obtainable for 690 episodes. Sixty six (10%) cases were due to a cefotaxime non-susceptible strain with a 30-day mortality rate of 8%. Variables associated with 30-day mortality were age, chronic liver disease, septic shock, and the McCabe score. Infection by a cefotaxime non-susceptible S. pneumoniae did not increase the mortality rate. Conclusion: Despite the prevalence of cefotaxime, non-susceptible S. pneumoniae has increased in recent years. We found no evidence to suggest that patients hospitalized with bacteremic pneumonia due to these strains had worse clinical outcomes than patients with susceptible strains.

Risk factors for death from invasive pneumococcal disease, Europe, 2010

Risk varies by Streptococcus pneumoniae serotype.

We studied the possible association between patient age and sex, clinical presentation, Streptococcus pneumoniae serotype, antimicrobial resistance, and death in invasive pneumococcal disease cases reported by 17 European countries during 2010. The study sample comprised 2,921 patients, of whom 56.8% were men and 38.2% were >65 years of age. Meningitis occurred in 18.5% of cases. Death was reported in 264 (9.0%) cases. Older age, meningitis, and nonsusceptibility to penicillin were significantly associated with death. Non–pneumococcal conjugate vaccine (PCV) serotypes among children <5 years of age and 7-valent PCV serotypes among persons 5–64 years of age were associated with increased risk for death; among adults >65 years of age, risk did not differ by serotype. These findings highlight differences in case-fatality rates between serotypes and age; thus, continued epidemiologic surveillance across all ages is crucial to monitor the long-term effects of PCVs.

Impact of preceding respiratory viral infections on the clinical severity of patients with pneumococcal pneumonia

Background

This study aimed to investigate the impact of preceding respiratory viral infections (RVI) on the clinical severity of pneumococcal pneumonia patients.

Methods

A retrospective observational study was conducted at a university hospital from January 2009 to March 2013. Study subjects included adults (aged ≥18 years) with pneumococcal pneumonia who had undergone laboratory tests for RVI. Multivariate logistic regression analysis was performed to identify risk factors associated with severe pneumococcal pneumonia, defined as severity with the Pneumonia Severity Index (PSI) score ≥91.

Results

In total, 191 patients with pneumococcal pneumonia were included for analysis and stratified into 2 groups: the severe group with a PSI score ≥91 (n = 99) and the non-severe group with a PSI score <91 (n = 92). Preceding RVIs were detected in 48 patients, including influenza A virus (n = 20), influenza B virus (n = 4), parainfluenza viruses (n = 5), metapneumovirus (n = 4), rhinovirus (n = 4), respiratory syncytial viruses (n = 6), coronaviruses (n = 2), and mixed viral infections (n = 3). In the multivariate logistic regression analysis, preceding RVIs (odds ratio [OR], 2·49; 95% confidence interval [CI], 1·10–5·60), male sex (OR, 2·58; 95% CI, 1·24–5·38), old age (OR, 2·92; 95% CI, 1·37–6·24), hypoalbuminemia (OR, 3·26; 95% CI, 1·56–6·84)], and azotemia (OR, 2·24; 95% CI, 1·08–4·67) were significantly associated with severe pneumococcal pneumonia.

Conclusion

This study suggests that preceding RVIs might be one of the risk factors affecting the clinical severity of pneumococcal pneumonia.

Pneumococcal vertebral osteomyelitis at three teaching hospitals in Japan, 2003-2011: analysis of 14 cases and a review of the literature

BACKGROUND

Pneumococcal vertebral osteomyelitis (PVO) is a rare disease whose clinical characteristics have not been clarified. This study aimed to investigate the clinical features and outcomes of patients with PVO.

METHODS

We retrospectively evaluated all adult patients diagnosed with PVO at three teaching hospitals in Japan from January 2003 to December 2011. All cases were identified through a review of the medical records of patients with invasive pneumococcal disease (IPD).

RESULTS

Among 208 patients with IPD, we identified 14 with PVO (6.4%; 95% CI, 3.5-10%). All 14 patients (nine male, five female; median age 69 years) had acquired PVO outside the hospital and had no recent history of an invasive procedure or back injury. Five patients (36%) had diabetes mellitus, and four (29%) had heavy alcohol intake. Fever (n = 13; 93%) or back pain/neck pain (n = 12; 86%) were present in most patients. The lumbar spine was affected in nine patients (64%) but the cervical spine was the site of infection in four patients (29%). All patients except one had a positive blood culture for Streptococcus pneumoniae, and there were no distant infected sites in most patients (n = 10; 71%). Intravenous beta-lactam therapy was initiated within 1 week after the onset of symptoms in 11 patients (79%). No patients died within 30 days, but one patient died from aspiration pneumonia on day 37 after admission.

CONCLUSIONS

PVO was relatively common among adult patients with IPD, and mortality was low in this study. S. pneumoniae may be the causative pathogen of vertebral osteomyelitis, especially among community-onset cases without a history of invasive procedures or back injury.

Antimicrobial resistance in Asia: current epidemiology and clinical implications

Antimicrobial resistance has become one of the most serious public health concerns worldwide. Although circumstances may vary by region or country, it is clear that some Asian countries are epicenters of resistance, having seen rapid increases in the prevalence of antimicrobial resistance of major bacterial pathogens. In these locations, however, the public health infrastructure to combat this problem is very poor. The prevalence rates of methicillin-resistant Staphylococcus aureus (MRSA), macrolide-resistant Streptococcus pneumoniae, and multidrug-resistant enteric pathogens are very high due to the recent emergence of extremely drug-resistant gram-negative bacilli in Asia. Because antimicrobial options for these pathogens are extremely limited, infections caused by antimicrobial-resistant bacteria are often associated with inappropriate antimicrobial therapy and poor clinical outcomes. Physicians should be aware of the current epidemiological status of resistance and understand the appropriate use of antimicrobial agents in clinical practice. This review focuses on describing the epidemiology and clinical implications of antimicrobial-resistant bacterial infections in Asian countries.

Regional epidemiology of invasive pneumococcal disease in Asian adults: epidemiology, disease burden, serotype distribution, and antimicrobial resistance patterns and prevention

OBJECTIVES

To summarize published data on the clinical and economic burden, epidemiology, antimicrobial resistance levels, serotype prevalence, and prevention strategies for pneumococcal disease among adults in Asia.

METHODS

We performed a systematic search of the PubMed database for relevant, peer-reviewed articles published between January 1995 and December 2011, covering China, Hong Kong, India, Indonesia, Japan, Malaysia, Pakistan, the Philippines, Singapore, South Korea, Taiwan, Thailand, and Vietnam.

RESULTS

Taiwan and Thailand had the most comprehensive epidemiological data on adult pneumococcal disease. Very little relevant data were found for Indonesia, Pakistan, the Philippines, and Vietnam; surveillance is urgently needed in these countries. The emergence and spread of resistance emphasize the importance of vaccination to prevent infection in adults at increased risk for serious pneumococcal disease. Vaccination policies and opinions on the efficacy of vaccination vary widely in Asian countries, although a new option in the form of a pneumococcal conjugate vaccine is now available.

CONCLUSIONS

Increased awareness of the public health and economic benefits of pneumococcal vaccination is critically needed to help both the public and policymakers in making changes to vaccination policies in the region. Maximizing access to pneumococcal vaccines will decrease the number of hospitalizations, complications, and deaths associated with pneumococcal disease.

Purulent pericarditis with concurrent detection of Streptococcus pneumoniae and malignant squamous cells in pericardial fluid

Pneumococcal pericarditis complicated by a malignant effusion has not been reported previously. We experienced an independent 62-year-old man with lung cancer who was hospitalized for acute onset of atrial flutter and moderate pericardial effusion. He was afebrile; however, pericardiocentesis showed Streptococcus pneumoniae and malignant squamous cells in purulent pericardial fluid. This case shows that clinicians should keep in mind the possibility of afebrile bacterial pericarditis in cancer patients with pericardial effusions and that cultures of pericardial fluid should be performed in such patients along with cytological examinations.