Predicting bacteremic pneumonia in HIV-1-infected patients consulting the ED

Burden of pneumococcal disease among adults in Southern Europe (Spain, Portugal, Italy, and Greece): a systematic review and meta-analysis

The aim was to summarize pneumococcal disease burden data among adults in Southern Europe and the potential impact of vaccines on epidemiology. Of 4779 identified studies, 272 were selected. Invasive pneumococcal disease (IPD) incidence was 15.08 (95% CI 11.01-20.65) in Spain versus 2.56 (95% CI 1.54-4.24) per 100,000 population in Italy. Pneumococcal pneumonia incidence was 19.59 (95% CI 10.74-35.74) in Spain versus 2.19 (95% CI 1.36-3.54) per 100,000 population in Italy. Analysis of IPD incidence in Spain comparing pre-and post- PCV7 and PCV13 periods unveiled a declining trend in vaccine-type IPD incidence (larger and statistically significant for the elderly), suggesting indirect effects of childhood vaccination programme. Data from Portugal, Greece and, to a lesser extent, Italy were sparse, thus improved surveillance is needed. Pneumococcal vaccination uptake, particularly among the elderly and adults with chronic and immunosuppressing conditions, should be improved, including shift to a higher-valency pneumococcal conjugate vaccine when available.

Treating HIV-Positive/Non-AIDS Patients for Community-Acquired Pneumonia with ART

PURPOSE OF REVIEW

This article reviews the most recent publications on community-acquired pneumonia (CAP) in the HIV-infected population on antiretroviral therapy (ART), focusing on epidemiology, prognostic factors, etiology, and antimicrobial therapy. The data discussed here were mainly obtained from a non-systematic review using Medline and references from relevant articles.

RECENT FINDINGS

CAP remains a major cause of morbidity and mortality among HIV-infected patients and incurs high health costs despite the introduction of ART. HIV-infected patients are generally known to be more susceptible to bacterial pneumonia. Streptococcus pneumoniae is the most frequently reported pathogen in HIV-infected patients on ART, who present a higher rate of bacteremia than non-HIV-infected patients. Several studies have also examined microbial etiology and prognostic factors of CAP in HIV-infected patients on ART. Despite the high rate of bacterial pneumonia in these patients, mortality rates are not higher than in patients without HIV infection.

Community-acquired bacterial pneumonia in adult HIV-infected patients

INTRODUCTION

Despite active antiretroviral therapy (ART), community-acquired pneumonia (CAP) remains a major cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected patients and incurs high health costs. Areas covered: This article reviews the most recent publications on bacterial CAP in the HIV-infected population, focusing on epidemiology, prognostic factors, microbial etiology, therapy, and prevention. The data discussed here were mainly obtained from a non-systematic review using Medline, and references from relevant articles. Expert commentary: HIV-infected patients are more susceptible to bacterial CAP. Although ART improves their immune response and has reduced CAP incidence, these patients continue to present increased risk of pneumonia in part because they show altered immunity and because immune activation persists. The risk of CAP in HIV-infected patients and the probability of polymicrobial or atypical infections are inversely associated with the CD4 cell count. Mortality in HIV-infected patients with CAP ranges from 6% to 15% but in well-controlled HIV-infected patients on ART the mortality is low and similar to that seen in HIV-negative individuals. Vaccination and smoking cessation are the two most important preventive strategies for bacterial CAP in well-controlled HIV-infected patients on ART.

Accuracy of C - Reactive protein as a bacterial infection marker in critically immunosuppressed patients: A systematic review and meta-analysis

BACKGROUND

There is a need for a better understanding of the role of C-reactive protein (CRP) as a valid marker for the detection of bacterial infections in critically immunosuppressed patients. A high negative predictive value of CRP is also needed to rule out sepsis and bacterial infections in immunocompetent patients. However, few studies have evaluated the performance of CRP in immunocompromised hosts. The aim of the present study was to evaluate the performance of CRP as a marker of infection in critically immunosuppressed patients.

METHODS

The inclusion criterion was immunosuppression for which CRP was used as a bacterial infection marker. Searches were performed in the Cochrane Register, MEDLINE, EMBASE, SCOPUS, Web OF Science, LILACS and CINAHL databases. We applied the Quality Assessment of Diagnostic Accuracy Studies tool 2 (QUADAS 2) to evaluate the quality of the articles and evaluated the test accuracy parameters using hierarchical summary receiver operating characteristic (HSROC) curves and bivariate random effect models.

RESULTS

Only 13 of 21 studies produced quantitative results. We analyzed all studies using the random effects method (restricted maximum likelihood) and obtained a joint diagnostic odds ratio (DOR) of 3.04 (95% confidence interval [CI] 1.71-5.40) with heterogeneity (I²=91%, Q=181.48, p<0.001). Therefore, a bivariate model was applied. Analyzing the tuberculosis carrier, steroid user, or presence of opportunistic infection subgroups, as described in the proposal, was not possible due to the lack of information on these topics included in the articles.

CONCLUSIONS

CRP appears to be a good screening tool for sepsis in critically immunosuppressed patients. Submitted PROSPERO 2015: CRD42015019329.

Streptococcus pneumoniae antigen in urine: diagnostic usefulness and impact on outcome of bacteraemic pneumococcal pneumonia in a large series of adult patients

BACKGROUND AND OBJECTIVE

Urinary pneumococcal antigen detection provides good results in the diagnosis of pneumococcal pneumonia but has rarely been used in bacteraemic pneumococcal pneumonia and it is not known whether it is associated with outcome in this type of pneumonia. Our objectives were to assess the usefulness of an immunochromatographic technique for detecting the pneumococcal antigen in urine in a large prospective study of patients with bacteraemic pneumococcal pneumonia and explore any potential association with outcomes.

METHODS

This study, carried out over 8 years, included all adult immunocompetent patients admitted for bacteraemic pneumococcal pneumonia. An immunochromatographic test for the Streptococcus pneumoniae antigen in urine was performed in the first 24 h. The sensitivity of test was assessed and patients were divided into two groups according to test results to explore differences on admission and during the course of the illness using logistic regression models.

RESULTS

Of the 350 patients with bacteraemic pneumococcal pneumonia included, 261 (74.6%) were positive for the antigen. Patient characteristics were very similar on admission and differences in severity (Pneumonia Severity Index) were not statistically significant. In the adjusted analysis, antigen-positive patients had a higher risk of intensive care unit admission, treatment failure and adverse outcome.

CONCLUSIONS

The sensitivity of the immunochromatographic urinary antigen test was 74.6% and positive results were associated with poorer clinical outcome. We therefore recommend systematic use of this test when pneumonia is diagnosed in the emergency department.

Emergency department (ED) utilization by HIV-infected ED patients in the United States in 2009 and 2010 - a national estimation

OBJECTIVES

The aim of the study was to describe the emergency department (ED) resource utilization patterns of ED visits by patients reported to be HIV-infected in the USA in 2009 and 2010 and to compare them with those of the general ED patient population.

METHODS

We identified demographics, HIV infection status, and ED utilization patterns in 2009 and 2010 from a weighted sample of US ED visits using the National Hospital Ambulatory Medical Care Survey, a nationally representative survey. Data on visits by patients aged ≥ 13 years were analysed using procedures for multiple-stage survey data.

RESULTS

In 2009 and 2010, 1 192 535 visits were documented for HIV-infected patients. The estimated annual ED visit rates were 633 per 1000 known HIV-infected persons and 438 per 1000 non-HIV-infected persons [rate difference 195; 95% confidence interval (CI) 194, 197]. While no difference was recorded in the level of acuity between HIV-infected ED patients and general ED patients, the total number of diagnostic/screening services ordered and medications administered in the ED was significantly higher for visits by HIV-infected patients. HIV-infected patients making ED visits also had a longer duration of stays [mean 5.4 h (95% CI 4.6, 6.2 h) vs. 3.6 h (95% CI 3.5, 3.8 h) for HIV-uninfected patients] and were more likely to be admitted [28% (95% CI 22, 34%) vs. 15% (95% CI 14, 16%), respectively] than their non-HIV-infected counterparts.

CONCLUSIONS

ED visits by HIV-infected individuals occur at rates higher than those of visits by the general population, and consume significantly more ED resources than visits by the general population. These national findings represent baseline prior to full implementation of the 2010 Patient Protection and Affordable Care Act.

Systematic review and meta-analysis of a urine-based pneumococcal antigen test for diagnosis of community-acquired pneumonia caused by Streptococcus pneumoniae

Standard culture methods for diagnosis of Streptococcus pneumoniae pneumonia take at least 24 h. The BinaxNOW urine-based test for S. pneumoniae (BinaxNOW-SP) takes only 15 min to conduct, potentially enabling earlier diagnosis and targeted treatment. This study was conducted to assess whether the use of BinaxNOW-SP at the time of hospital admission would provide adequate sensitivity and specificity for diagnosis of community-acquired pneumonia (CAP) in adult patients. We searched PubMed, EMBASE/OVID, Cochrane Collaboration, Centre for Reviews and Dissemination, INAHTA, and CADTH for diagnostic or etiologic studies of hospitalized predominately adult patients with clinically defined CAP that reported the diagnostic performance of BinaxNOW-SP versus cultures. Two authors independently extracted study details and diagnostic two-by-two tables. We found that 27 studies met our inclusion criteria, and three different reference standards were used between them. A bivariate meta-analysis of 12 studies using a composite of culture tests as the reference standard estimated the sensitivity of BinaxNOW-SP as 68.5% (95% credibility interval [CrI], 62.6% to 74.2%) and specificity as 84.2% (95% CrI, 77.5% to 89.3%). A meta-analysis of all 27 studies, adjusting for the imperfect and variable nature of the reference standard, gave a higher sensitivity of 74.0% (CrI, 66.6% to 82·3%) and specificity of 97.2% (CrI, 92.7% to 99.8%). The analysis showed substantial heterogeneity across studies, which did not decrease with adjustment for covariates. We concluded that the higher pooled sensitivity (compared to culture) and high specificity of BinaxNOW-SP suggest it would be a useful addition to the diagnostic workup for community-acquired pneumonia. More research is needed regarding the impact of BinaxNOW-SP on clinical practice.

Does HIV status affect the aetiology, bacterial resistance patterns and recommended empiric antibiotic treatment in adult patients with bloodstream infection in Cambodia?

OBJECTIVE

The microbiologic causes of bloodstream infections (BSI) may differ between HIV-positive and HIV-negative patients and direct initial empiric antibiotic treatment (i.e. treatment before culture results are available). We retrospectively assessed community-acquired BSI episodes in adults in Cambodia according to HIV status for spectrum of bacterial pathogens, antibiotic resistance patterns and appropriateness of empiric antibiotics.

METHODS

Blood cultures were systematically performed in patients suspected of BSI in a referral hospital in Phnom Penh, Cambodia. Data were collected between 1 January 2009 and 31 December 2011.

RESULTS

A total of 452 culture-confirmed episodes of BSI were recorded in 435 patients, of whom 17.9% and 82.1% were HIV-positive and HIV-negative, respectively. Escherichia coli accounted for one-third (n = 155, 32.9%) of 471 organisms, with similar rates in both patient groups. Staphylococcus aureus and Salmonella cholereasuis were more frequent in HIV-positive vs. HIV-negative patients (17/88 vs. 38/383 (P = 0.02) and 10/88 vs. 5/383 (P < 0.001)). Burkholderia pseudomallei was more common in HIV-negative than in HIV-positive patients (39/383 vs. 2/88, P < 0.001). High resistance rates among commonly used antibiotics were observed, including 46.6% ceftriaxone resistance among E. coli isolates. Empiric antibiotic treatments were similarly appropriate in both patient groups but did not cover antibiotic-resistant E. coli (both patient groups), S. aureus (both groups) and B. pseudomallei (HIV-negative patients).

CONCLUSION

The present data do not warrant different empiric antibiotic regimens for HIV-positive vs. HIV-negative patients in Cambodia. The overall resistance rates compromise the appropriateness of the current treatment guidelines.

Risk factors and pathogenic significance of bacteremic pneumonia in adult patients with community-acquired pneumococcal pneumonia

OBJECTIVE

This study was performed to identify risk factors for the development of bacteremic pneumonia and to evaluate the impact of bacteremia on the outcome of pneumococcal pneumonia.

METHODS

Using a database from a surveillance study of community-acquired pneumococcal pneumonia, we compared data of the bacteremic group with that of the non-bacteremic group.

RESULTS

Among 981 adult patients with pneumococcal pneumonia, 114 (11.6%) patients who had documented pneumococcal bacteremia were classified into the bacteremic group. In a multivariable analysis, use of immunosuppressant drugs, younger age (<65 years), and DM were independent risk factors associated with the development of bacteremic pneumonia among patients with pneumococcal pneumonia (all P < 0.05). The mortality rate was significantly higher in the bacteremic group than in the non-bacteremic group (28.6% vs. 8.5%; P < 0.001). The multivariable analysis revealed that concomitant bacteremia was one of the significant risk factors associated with mortality (OR, 2.57; 95% CI, 1.24-5.29), along with cerebrovascular disease and presentation with septic shock (all P < 0.05).

CONCLUSIONS

Bacteremia was a common finding in pneumococcal pneumonia and was associated with a higher mortality rate. Several clinical variables may be useful for predicting bacteremic pneumonia among patients with pneumococcal pneumonia.

Microbiologic profile of endodontic infections from HIV- and HIV+ patients using multiple-displacement amplification and checkerboard DNA-DNA hybridization

OBJECTIVE

To compare the microbiota of endodontic infections in necrotic pulp from HIV-negative and HIV-positive subjects.

MATERIALS AND METHODS

Root canal samples from necrotic pulp were collected from 40 HIV- and 20 HIV+ subjects. Pulps were amplified using multiple displacement amplification (MDA). Then, checkerboard DNA-DNA hybridization was employed to assess the levels of 107 microbial taxa. The percentage of DNA probe count and the percentage of teeth colonized by each test species were investigated. Significant differences between groups regarding proportions of taxa and prevalence of the test species were sought using the Mann-Whitney test and the Chi-square analysis, respectively.

RESULTS

The most prevalent taxa detected were Dialister pneumosintes, Stenotrophomonas maltophilia, Streptococcus sobrinus, Corynebacterium diphteriae, and Helicobacter pylori among HIV- subjects and D. pneumosintes, Prevotella tannerae, Porphyromonas gingivalis, Parvimonas micra, Prevotella nigrescens, and Corynebacterium diphtheriae among HIV+ individuals. D. pneumosintes, C. diphtheria, and C. albicans were the most abundant species in the HIV- group, whereas the predominant taxa in HIV+ samples were P. tannerae, D. pneumosintes and Olsenella uli. P. tannerae, O. uli, Veilonella dispar, Bacteroides fragilis, and Actinomyces meyeri were significantly more abundant in HIV+ samples.

CONCLUSIONS

There were significant differences in the prevalence and proportions of specific microbial taxa between HIV- and HIV+ individuals. The root canal microbiota may represent a reservoir of important oral and medical pathogens, mainly in HIV+ individuals.

Lung Disease in Older Patients with HIV

Successful treatment of HIV with combination antiretroviral therapy (ART) has resulted in an aging HIV-infected population. As HIV-infected patients are living longer, noninfectious pulmonary diseases are becoming increasingly prevalent with a proportional decline in the incidence of opportunistic infections (OIs). Pulmonary OIs such as Pneumocystis jirovecii pneumonia (PCP) and tuberculosis are still responsible for a significant proportion of pulmonary diseases in HIV-infected patients. However, bacterial pneumonia (BP) and noninfectious pulmonary diseases such as chronic obstructive pulmonary disease (COPD), lung cancer, pulmonary arterial hypertension (PAH), and interstitial lung disease (ILD) account for a growing number of pulmonary diseases in aging HIV-infected patients. The purpose of this chapter is to discuss the spectrum and management of pulmonary diseases in aging HIV-infected patients, although limited data exists to guide management of many noninfectious pulmonary diseases in HIV-infected patients. In the absence of such data, treatment of lung diseases in HIV-infected patients should generally follow guidelines for management established in HIV-uninfected patients.