Pneumonia severity index in the immunocompromised

Validation of risk scores for prediction of severe pneumonia in kidney transplant recipients hospitalized with community-acquired pneumonia

PURPOSE

Risk scores for community-acquired pneumonia (CAP) are widely used for standardized assessment in immunocompetent patients and to identify patients at risk for severe pneumonia and death. In immunocompromised patients, the prognostic value of pneumonia-specific risk scores seems to be reduced, but evidence is limited. The value of different pneumonia risk scores in kidney transplant recipients (KTR) is not known.

METHODS

Therefore, we retrospectively analyzed 310 first CAP episodes after kidney transplantation in 310 KTR. We assessed clinical outcomes and validated eight different risk scores (CRB-65, CURB-65, DS-CRB-65, qSOFA, SOFA, PSI, IDSA/ATS minor criteria, NEWS-2) for the prognosis of severe pneumonia and in-hospital mortality. Risk scores were assessed up to 48 h after admission, but always before an endpoint occurred. Multiple imputation was performed to handle missing values.

RESULTS

In total, 16 out of 310 patients (5.2%) died, and 48 (15.5%) developed severe pneumonia. Based on ROC analysis, sequential organ failure assessment (SOFA) and national early warning score 2 (NEWS-2) performed best, predicting severe pneumonia with AUC of 0.823 (0.747-0.880) and 0.784 (0.691-0.855), respectively.

CONCLUSION

SOFA and NEWS-2 are best suited to identify KTR at risk for the development of severe CAP. In contrast to immunocompetent patients, CRB-65 should not be used to guide outpatient treatment in KTR, since there is a 7% risk for the development of severe pneumonia even in patients with a score of zero.

Removable Denture Wearing as a Risk Predictor for Pneumonia Incidence and Time to Event in Older Adults

INTRODUCTION

Older adults are more susceptible to a common respiratory infection: pneumonia. Nearly 1 million older adults per year are hospitalized for community-acquired pneumonia in the United States.

OBJECTIVE

To examine whether wearing removable dentures are associated with an increased risk of pneumonia incidence in a geriatric population.

METHODS

We conducted a retrospective cohort study among patients >65 y of age within a large academic health system (University of Rochester Medical Center). The medical and dental electronic records from 2010 to 2018 were reviewed and used for data collection. The exposure was removable denture wearing. The main outcome variables were the incidence of pneumonia and time to event of pneumonia. A Cox proportional hazards regression was used to examine the association between pneumonia onset and wearing removable dentures, adjusting for demographics, socioeconomic status, and medical and dental conditions.

RESULTS

A total of 2,364 patients were included, with 1,189 (50.29%) in the denture-wearing group and 1,175 (49.70%) in the non-denture wearing group. The annual pneumonia incidence rate per 100,000 persons was 1,191 in the denture-wearing group and 128 per 100,000 persons in the non-denture wearing group, with a crude incidence rate ratio of 9.33 (95% CI, 5.41 to 18.81; P < 0.0001). The mean ± SD age of the pneumonia onset was 78.0 ± 10.0 and 78.6 ± 9.0 y among denture-wearing and nonwearing groups (P = 0.84). The time to event of pneumonia was associated with removable denture wearing (yes/no; hazard ratio, 7.68 [95% CI, 3.91 to 15.08]; P < 0.001) after adjusting for covariates.

CONCLUSIONS

Wearing removable dentures was found to be a risk predictor for pneumonia incidence among the geriatric population even after accounting for other risk factors.

KNOWLEDGE TRANSFER STATEMENT

Wearing removable dentures was found to be a risk predictor of pneumonia incidence among older adults. Although the current study does not imply a causal relationship between denture wearing and pneumonia, clinicians and older patients could reference the study results when choosing dental prostheses to restore missing teeth.

Limited prognostic accuracy of the CRB-65 and qSOFA in patients presenting with pneumonia and immunosuppression

BACKGROUND

Scores for risk prediction used in immunocompetent patients with sepsis or pneumonia are poorly evaluated in immunocompromised patients. Therefore, we evaluated the prognostic value of the qSOFA- and CRB-65-criteria in immunocompromised patients presenting with pneumonia.

METHODS

Retrospective cohort study including consecutive patients hospitalized with pneumonia and immunosuppression without treatment restrictions. The qSOFA and CRB-65 criteria were documented in the emergency department. Outcome was defined as need of mechanical ventilation (MV) or vasopressor support (VS) and/or hospital-mortality.

RESULTS

41 of 198 (21%) patients reached the outcome and 10% died. Both, the CRB-65 and qSOFA- were independently associated with the outcome (all p<0.01), but age was not predictive. ROC curve analysis showed moderate predictive potential for both scores (CRB-65: AUC 0.63 and qSOFA: 0.69). With scores of 0, the negative predictive values were below 90% (CRB-65: 9/60 and qSOFA: 12/105 missed patients). With scores > 1, the positive predictive values were 36% (CRB-65) and 58% (qSOFA), respectively.

CONCLUSIONS

Both, the qSOFA and the CRB-65 only showed moderate prognostic value, and negative predictive values were inadequate to exclude organ failure or death in patients with immunosuppression. In this population, age was not a predictive parameter. Patients with > 1 positive vital sign criterion measured by both scores should be assessed for organ failure.

Treatment of Community-Acquired Pneumonia in Immunocompromised Adults: A Consensus Statement Regarding Initial Strategies

Background

Community-acquired pneumonia (CAP) guidelines have improved the treatment and outcomes of patients with CAP, primarily by standardization of initial empirical therapy. But current society-published guidelines exclude immunocompromised patients.

Research Question

There is no consensus regarding the initial treatment of immunocompromised patients with suspected CAP.

Study Design and Methods

This consensus document was created by a multidisciplinary panel of 45 physicians with experience in the treatment of CAP in immunocompromised patients. The Delphi survey methodology was used to reach consensus.

Results

The panel focused on 21 questions addressing initial management strategies. The panel achieved consensus in defining the population, site of care, likely pathogens, microbiologic workup, general principles of empirical therapy, and empirical therapy for specific pathogens.

Interpretation

This document offers general suggestions for the initial treatment of the immunocompromised patient who arrives at the hospital with pneumonia.

Treating bacterial pneumonia in people living with HIV

Introduction: Bacterial pneumonia remains an important cause of morbidity and mortality in people living with HIV (PLWH) in the antiretroviral therapy (ART) era. In addition to being immunocompromised, as reflected by low CD4 cell counts and elevated HIV viral loads, PLWH often have other behaviors associated with an increased risk of pneumonia including smoking and injected drug use. As PLWH are aging, comorbid conditions such as chronic obstructive pulmonary disease (COPD), cancers, and cardiovascular, renal and liver diseases are emerging as additional risk factors for pneumonia. Pathogens are often similar to those in HIV-uninfected individuals; however, PLWH are at risk for unusual and/or multi-drug resistant organisms causing bacterial pneumonia based, in part, on their CD4 cell counts and other exposures. Areas covered: In this review, we focus on the recognition and management of bacterial community-acquired pneumonia (CAP) in PLWH. Along with antimicrobial treatment, we discuss prevention strategies such as vaccination and smoking cessation. Expert opinion: Early initiation of ART after HIV infection can decrease the risk of pneumonia. Improved efforts at vaccination, smoking cessation, and reduction of other substance use are urgently needed in PLWH to decrease the risk for bacterial pneumonia. As PLWH are aging, comorbidities are additional risk factors for bacterial CAP.

Prognostic indicators in the World Health Organization's algorithm for seriously ill HIV-infected inpatients with suspected tuberculosis

BACKGROUND

Criteria for the 2007 WHO algorithm for diagnosing tuberculosis among HIV-infected seriously ill patients are the presence of one or more danger signs (respiratory rate > 30/min, heart rate > 120/min, temperature > 39 °C, and being unable to walk unaided) and cough ≥ 14 days. Determining predictors of poor outcomes among HIV-infected inpatients presenting with WHO danger signs could result in improved treatment and diagnostic algorithms.

METHODS

We conducted a prospective cohort study of inpatients presenting with any duration of cough and WHO danger signs to two regional hospitals in Cape Town, South Africa. The primary outcome was all-cause mortality up to 56 days post-discharge, and the secondary outcome a composite of any one of: hospital admission for > 7 days, died in hospital, transfer to a tertiary level or tuberculosis hospital. We first assessed the WHO danger signs as predictors of poor outcomes, then assessed the added value of other variables selected a priori for their ability to predict mortality in common respiratory opportunistic infections (CD4 count, body mass index (BMI), being on antiretroviral therapy (ART), hypotension, and confusion) by comparing the receiver operating characteristic (ROC) area under the curve (AUC) of the two multivariate models.

RESULTS

484 participants were enrolled, median age 36, 66% women, 53% had tuberculosis confirmed on culture. The 56-day mortality was 13.2%. Inability to walk unaided, low BMI, low CD4 count, and being on ART were independently associated with poor outcomes. The multivariate model of the WHO danger signs showed a ROC AUC of 0.649 (95% CI 0.582-0.717) for predicting 56-day mortality, which improved to ROC AUC of 0.740 (95% CI 0.681-0.800; p = 0.004 for comparison between the two ROC AUCs) with the multivariate model including the a priori selected variables. Findings were similar in sub-analyses of participants with culture-positive tuberculosis and with cough duration ≥ 14 days.

CONCLUSION

The study design prevented a rigorous evaluation of the prognostic value of the WHO danger signs. Our prognostic model could result in improved algorithms, but needs to be validated.

Presence of an Alcohol Use Disorder is Associated with Greater Pneumonia Severity in Hospitalized HIV-Infected Patients

PURPOSE

Pneumonia is common and more severe in human immunodeficiency virus (HIV)-infected patients. Alcohol consumption in pneumonia patients without HIV is associated with excess mortality and morbidity. However, studies are lacking on the impact of alcohol on pneumonia and HIV. Our goal was to determine if alcohol use was an independent risk factor for pneumonia severity in HIV-infected patients.

METHODS

Secondary analysis of prospective cohort study data evaluating early bronchoscopy for pneumonia diagnosis in HIV patients between 2007 and 2011 was conducted. We defined AUDs using an alcohol use disorder identification test (AUDIT) score as follows: ≥8 indicates hazardous drinking and ≥14 indicates dependence. We quantified pneumonia severity using the pneumonia severity index (PSI). Multivariable linear regression was used to investigate the independent association between alcohol and pneumonia severity.

RESULTS

A total of 196 HIV+ individuals comprised our cohort. Most cohort subjects were middle-aged African American men. Most subjects (70 %) reported not taking antiretroviral therapy. The overall prevalence of hazardous drinking was 24 % in our cohort (48/196) with 10 % (19/196) meeting the criteria for alcohol dependence. Alcohol consumption was significantly associated with pneumonia severity (r = 0.25, p < 0.001). Hazardous drinking (β-coefficient 10.12, 95 % CI 2.95-17.29, p = 0.006) and alcohol dependence (β-coefficient 12.89, 95 % CI 2.59-23.18, p = 0.014) were independent risk factors for pneumonia severity. Reported homelessness and men who have sex with men (MSM) status remained independent risk factors for more severe pneumonia after adjustment for the effects of alcohol.

CONCLUSIONS

In a cohort of HIV patients with pneumonia, presence of an AUD was an independent risk factor for pneumonia severity. Homelessness and MSM status were associated with greater pneumonia severity in AUD patients.

CURB-65 and other markers of illness severity in community-acquired pneumonia among HIV-positive patients

As the relative burden of community-acquired bacterial pneumonia among HIV-positive patients increases, adequate prediction of case severity on presentation is crucial. We sought to determine what characteristics measurable on presentation are predictive of worse outcomes. We studied all admissions for community-acquired bacterial pneumonia over one year at a tertiary centre. Patient demographics, comorbidities, HIV-specific markers and CURB-65 scores on Emergency Department presentation were reviewed. Outcomes of interest included mortality, bacteraemia, intensive care unit admission and orotracheal intubation. A total of 396 patients were included: 49 HIV-positive and 347 HIV-negative. Mean CURB-65 score was 1.3 for HIV-positive and 2.2 for HIV-negative patients (p < 0.0001), its predictive value for mortality being maintained in both groups (p = 0.03 and p < 0.001, respectively). Adjusting for CURB-65 scores, HIV infection by itself was only associated with bacteraemia (adjusted odds ratio [AOR] 7.1, 95% CI [2.6-19.5]). Patients with < 200 CD4 cells/µL presented similar CURB-65 adjusted mortality (aOR 1.7, 95% CI [0.2-15.2]), but higher risk of intensive care unit admission (aOR 5.7, 95% CI [1.5-22.0]) and orotracheal intubation (aOR 9.1, 95% CI [2.2-37.1]), compared to HIV-negative patients. These two associations were not observed in the > 200 CD4 cells/µL subgroup (aOR 2.2, 95% CI [0.7-7.6] and aOR 0.8, 95% CI [0.1-6.5], respectively). Antiretroviral therapy and viral load suppression were not associated with different outcomes (p > 0.05). High CURB-65 scores and CD4 counts < 200 cells/µL were both associated with worse outcomes. Severity assessment scales and CD4 counts may both be helpful in predicting severity in HIV-positive patients presenting with community-acquired bacterial pneumonia.

An Approach to a Pulmonary Infiltrate in Solid Organ Transplant Recipients

The onset of a pulmonary infiltrate in a solid organ transplant (SOT) recipient is both a challenging diagnostic and therapeutic challenge. We outline the potential aetiologies of a pulmonary infiltrate in a SOT recipient, with particular attention paid to fungal pathogens. A diagnostic and empirical therapy approach to a pulmonary infiltrate, especially invasive fungal disease (IFD) in SOT recipients, is provided.

A Clinical Predictor Score for 30-Day Mortality among HIV-Infected Adults Hospitalized with Pneumonia in Uganda

Background

Pneumonia is a major cause of mortality among HIV-infected patients. Pneumonia severity scores are promising tools to assist clinicians in predicting patients’ 30-day mortality, but existing scores were developed in populations infected with neither HIV nor tuberculosis (TB) and include laboratory data that may not be available in resource-limited settings. The objective of this study was to develop a score to predict mortality in HIV-infected adults with pneumonia in TB-endemic, resource-limited settings.

Methods

We conducted a secondary analysis of data from a prospective study enrolling HIV-infected adults with cough ≥2 weeks and <6 months and clinically suspected pneumonia admitted to Mulago Hospital in Kampala, Uganda from September 2008 to March 2011. Patients provided two sputum specimens for mycobacteria, and those with Ziehl-Neelsen sputum smears that were negative for mycobacteria underwent bronchoscopy with inspection for Kaposi sarcoma and testing for mycobacteria and fungi, including Pneumocystis jirovecii. A multivariable best subsets regression model was developed, and one point was assigned to each variable in the model to develop a clinical predictor score for 30-day mortality.

Results

Overall, 835 patients were studied (mean age 34 years, 53.4% female, 30-day mortality 18.2%). A four-point clinical predictor score was identified and included heart rate >120 beats/minute, respiratory rate >30 breaths/minute, oxygen saturation <90%, and CD4 cell count <50 cells/mm³. Patients’ 30-day mortality, stratified by score, was: score 0 or 1, 12.6%, score 2 or 3, 23.4%, score 4, 53.9%. For each 1 point change in clinical predictor score, the odds of 30-day mortality increased by 65% (OR 1.65, 95% CI 1.39-1.96, p <0.001).

Conclusions

A simple, four-point scoring system can stratify patients by levels of risk for mortality. Rapid identification of higher risk patients combined with provision of timely and appropriate treatment may improve clinical outcomes. This predictor score should be validated in other resource-limited settings.

Enhanced inflammation in aged mice following infection with Streptococcus pneumoniae is associated with decreased IL-10 and augmented chemokine production

Streptococcus pneumoniae is the most common cause of severe pneumonia in the elderly. However, the impact of aging on the innate inflammatory response to pneumococci is poorly defined. We compared the innate immune response in old vs. young adult mice following infection with S. pneumoniae. The accumulation of neutrophils recovered from bronchoalveolar lavage fluid and lung homogenates was increased in aged compared with young adult mice, although bacterial outgrowth was similar in both age groups, as were markers of microvascular leak. Aged mice had similar levels of IL-1β, TNF, IFN-γ, IL-17, and granulocyte colony-stimulating factor following S. pneumoniae infection, compared with young mice, but increased levels of the chemokines CXCL9, CXCL12, CCL3, CCL4, CCL5, CCL11, and CCL17. Moreover, levels of IL-10 were significantly lower in aged animals. Neutralization of IL-10 in infected young mice was associated with increased neutrophil recruitment but no decrease in bacterial outgrowth. Furthermore, IL-10 neutralization resulted in increased levels of CCL3, CCL5, and CXCL10. We conclude that aging is associated with enhanced inflammatory responses following S. pneumoniae infection as a result of a compromised immunomodulatory cytokine response.

Predicting pneumonia mortality using CURB-65, PSI, and patient characteristics in patients presenting to the emergency department of a comprehensive cancer center

The prognostic accuracy of the CURB-65 criteria and pneumonia severity index (PSI) in immunocompromised cancer patients with pneumonia is unknown. We sought to determine whether CURB-65 and PSI predict 28-day mortality in cancer patients with pneumonia, and identify other factors that predispose cancer patients with pneumonia to a high mortality risk. We assessed sensitivities, specificities, predictive values, and areas under the receiver operating curve area under the curve (AUC) of the CURB-65 and PSI in predicting the 28-day mortality of cancer patients presenting to our institution's emergency department with pneumonia. We used the DeLong and Clarke–Pearson approach to determine whether the addition of other risk factors improved the scales' performances. The overall and pneumonia-related 28-day mortality rates were 20.2% (n = 44) and 17.4% (n = 38), respectively. In predicting 28-day mortality, the CURB-65 score had sensitivity of 45% and specificity of 81%, and the PSI score had sensitivity of 82% and specificity of 34%. The CURB-65 and PSI discriminated poorly between fatal and nonfatal pneumonia cases (AUCs, 0.664 and 0.658, respectively; 95% confidence interval [CI], 0.57–0.75 for each). The addition of radiation therapy (RT) within 4 weeks and stem cell transplant (SCT) significantly improved the AUCs of the CURB-65 (0.75; 95% CI, 0.67–0.83) and PSI (0.73; 95% CI, 0.65-0.82). Inadequate performances of CURB-65 and PSI demonstrate that a tool for predicting pneumonia-related mortality in cancer patients and other immunocompromised populations is needed. Pneumonia patients who have undergone recent RT or (SCT) are at a high risk of dying from pneumonia and require special consideration when assessing pneumonia-related mortality risk.

Respiratory tract infections in the immunocompromised

PURPOSE OF REVIEW

Pulmonary infections are particularly common in the immunosuppressed host. This review discusses emerging threats, newer modalities of diagnostic tests and emerging treatment options, and also highlights the increasing problem of antimicrobial resistance.

RECENT FINDINGS

Nosocomial pneumonia is increasingly due to multidrug-resistant Gram-negative organisms in immunosuppressed patients. Viral pneumonias remain a very significant threat, present atypically and carry a high mortality. Aspergillosis remains the most common fungal infection, and infections due to Mucorales are increasing. Multidrug-resistant tuberculosis is on the increase throughout the world. Mixed infections are common and early bronchoscopy with appropriate microbiological tests, including molecular diagnostics, optimise management and reduce mortality.

CONCLUSION

Pulmonary infection remains the most frequent infectious complication in the immunocompromised host. These complex infections are often mixed, have atypical presentations and can be due to multidrug-resistant organisms. Multidisciplinary involvement in specialist centres with appropriate diagnostics, treatment and infection control improves outcome. There is a desperate need for new antimicrobial agents active against Gram-negative pathogens.

Impact of prior systemic corticosteroid use in patients admitted with community-acquired pneumonia

BACKGROUND AND OBJECTIVE

Limited information is available regarding the impact of prior outpatient use of systemic corticosteroids (SCS) in patients subsequently developing community-acquired pneumonia (CAP). We investigate the effects of prior SCS on severity of illness, microbiology and clinical outcomes for patients hospitalized with CAP.

METHODS

A retrospective cohort study of subjects with CAP (according to International Classification of Diseases, 9th edition codes) was conducted over a 3-year period at two tertiary teaching hospitals. Subjects were considered to be SCS users if they received oral corticosteroids prior to admission. Primary outcomes were severity of illness, microbiology and 30-day mortality.

RESULTS

Data were abstracted on 698 patients [prior SCS users, 75 (10.7%) versus prior non-SCS users 623 (89.3%)]. Prior SCS users were more likely to have chronic obstructive pulmonary disease. No differences were found in severity of disease at admission, microbiological etiology including opportunistic and drug-resistant pathogens and clinical outcomes, including 30-day mortality, intensive care unit admission, length of hospital stay, need for mechanical ventilation and need for vasopressors.

CONCLUSION

Prior SCS use is not associated with increased 30-day mortality for patients hospitalized with CAP. In addition, no differences were found in either the severity of the disease at the time of presentation or in the presence of the resistant or opportunistic pathogens among groups.

Radiological spectrum of pulmonary infections in patients post solid organ transplantation

Pneumonia remains an important source of morbidity and mortality in transplant recipients. Since clinical findings are nonspecific and cultures may be time-consuming, imaging plays an important role in establishing the probable etiology of pneumonia. Plain films are used as an initial study. However, they have a limited capacity in differentiating the causative factors. HRCT is used as a problem-solving tool in patients with unclear plain film findings and/or no response to treatment. The main advantage of HRCT is a very detailed depiction of the lung parenchyma. Even though HRCT findings are not always specific, there are several sings that are more common in certain types of pneumonia. The aim of the article is to present radiological findings suggestive of a particular causative microorganism and show how they can narrow the differential diagnosis when coupled with clinical data.

Host defenses against bacterial lower respiratory tract infection

Bacterial pneumonia continues to be a significant cause of morbidity and mortality worldwide. Recent studies have shown that lung epithelia signal through pattern recognition receptors to initiate the innate immune response. Other mediators of innate immunity against bacterial pneumonia include transepithelial dendritic cells, alveolar macrophages, and innate produces of IL-17. CD4+ T cells and B cells play a key role in eliminating and preventing the development of bacterial pneumonias. B cell development and maturation can be modulated by the lung epithelia through BAFF and APRIL, furthering our current understanding of the role of epithelial cells in the immune response.

Community-acquired pneumonia in immunocompromised older patients: incidence, causative organisms and outcome

The number of elderly patients in the community with immunosuppressive conditions has increased progressively over recent decades. We sought to determine the incidence, causative organisms and outcome of community-acquired pneumonia (CAP) occurring in immunocompromised older patients. We prospectively compared cases of CAP in immunocompromised and non-immunocompromised patients admitted to five public hospitals in three Spanish regions. Of 320 cases studied, 115 (36%) occurred in immunocompromised patients, including: solid or hematological malignancy (97), corticosteroids or other immunosuppressive drugs (44), solid organ or stem cell transplant (five), and other conditions (eight). The etiology was established in 44% of immunocompromised patients vs. 32% of non-immunocompromised patients (p 0.03). Streptococcus pneumoniae was the most common causative organism in both groups (29% vs. 21%; p 0.08), followed by Legionella pneumophila (3% vs. 6%; p 0.01). Gram-negative bacilli were more frequent among immunocompromised patients (5% vs. 0.5%; p <0.01), particularly Pseudomonas aeruginosa (3% vs. 0%; p 0.04). Nocardiosis was only observed in immunocompromised patients (two cases). Bacteremia occurred similarly in the two groups. No significant differences were found with respect to ICU admission (8%, in both groups) or the length of stay (12.5 vs. 10.4 days). The early (<48 h) (3.5 vs. 0.5%; p 0.04) and overall case-fatality rates (12% vs. 3%; p <0.01) were higher in immunocompromised patients. In conclusion, a substantial number of older patients hospitalized for CAP are immunocompromised. Although relatively uncommon, CAP due to gram-negative bacilli, including P. aeruginosa, is more frequent among these patients. CAP occurring in immunocompromised patients causes significant morbidity and mortality.

Predictors of pneumonia severity in HIV-infected adults admitted to an Urban public hospital

Data on outcomes of community-acquired pneumonia (CAP) in the HIV-infected population are mixed and the perception of worse outcomes in HIV may lead to excess hospitalization. We retrospectively evaluated the utility of the Pneumonia Severity Index, or PORT score, as a prediction rule for mortality in 102 HIV-infected adults hospitalized at an urban public hospital with CAP. Primary outcome was survival at 30 days. Secondary outcomes included survival on discharge, intensive care unit (ICU) admission, length of stay, and readmission within 30 days. The cohort was predominantly male (70%) with a mean age of 45.4 years (standard deviation [SD] ± 7.4). Mean CD4 cell count was 318 cells per microliter; 40 (39%) had CD4 less than 200 cells per microliter. Forty-three percent were on antiretroviral therapy at the time of admission and 31% on prophylactic antibiotics. Twelve patients had bacteremia on admission, predominantly with Streptococcus pneumoniae. Of the 46 patients with admission sputum cultures, 20 yielded an organism, most commonly Haemophilus influenzae and S. pneumoniae. Overall survival in the cohort was high, 96%. Most patients (81%) had a low PORT risk score (class I-III). PORT score predicted 30-day survival (p=0.01) and ICU admission (p=0.03), but antiretroviral use did not. In contrast to a prior study, we did not find that CD4 cell count predicted CAP outcome. Lack of stable housing was not associated with worse outcomes. The PORT score may be a valid tool to predict mortality and need for hospital admission in HIV-infected patients with CAP.

The value of prognostic indices for pneumonia

One of the most important decisions in the management of community-acquired pneumonia is deciding the care site, which affects morbidity, mortality, and costs. Clinical judgment alone is difficult and imprecise. The Pneumonia Severity Index score and the CURB-65 (confusion, urea nitrogen, respiratory rate, blood pressure, 65 years of age and older) score are validated prognostic indices to predict mortality, and they can identify low-risk patients who may be eligible for outpatient management. However, limitations of the scoring systems preclude their isolated use, and they can only be recommended as an aid to guide hospital admission decisions. The Pneumonia Severity Index score is slightly better at identifying the lowest risk patients, whereas CURB-65 is much simpler to use. As an adjunct to clinical judgment, we consider CURB-65 to be the most useful prognostic index for identifying low-risk patients.

Risk and protective factors related to mortality from pneumonia among middleaged and elderly community residents: the JACC Study

BACKGROUND

There have been few systematic investigations into risk and protective factors for pneumonia related mortality for community residents. This study investigated these factors utilizing a large cohort study on Japanese community residents.

METHODS

Subjects, 110,792 individuals (aged 40-79 years) enrolled in 1988-1990, were followed until death, or when they moved away from the surveyed communities, or the end of 2003. Pneumonia death was defined following 480-486 (International Classification of Diseases, 9th Revision) or J12-J18 (10th Revision). Age-adjusted and multivariate hazard ratios were calculated along with 95% confidence intervals using the Cox proportional hazards model.

RESULTS

With 1,112,747 person-years of the study, a total of 1,246 persons died of pneumonia. We found history of blood transfusion (multivariate hazard ratio=2.0 [95% confidence interval: 1.7-2.4]) was a potent novel risk factor. Walking 0.5-1 hour/day (0.8 [0.6-1.0]), 1+ hour/day (0.7 [0.6-0.8]), and/or a history of pregnancy (0.6 [0.4-0.9]) were found to reduce pneumonia mortality. A large body mass index (BMI) (25+kg/m²) was a protective factor (0.7 [0.5-0.8]), while low BMI (<18) was confirmed as a risk one (2.1 [1.7-2.6]). Smoking was an important preventable risk factor (1.6 [1.3-1.9], population attributable risk proportion=14%), and its cessation reduced risk (0.7 [0.5-1.0]) to levels comparable to never-smokers (0.7 [0.5-1.0]).

CONCLUSIONS

The risk and protective factors ascertained here for pneumonia mortality among community residents, history of blood transfusion, large BMI, and walking habits, warrant further study. Smoking cessation may effectively reduce pneumonia mortality.

Clinical judgment versus the Pneumonia Severity Index in making the admission decision

The Pneumonia Severity Index (PSI) is a validated risk assessment tool for patients with community-acquired pneumonia (CAP). Guidelines endorse outpatient treatment for patients deemed low risk, but experience shows that such patients are frequently hospitalized. We investigated the limitations of the PSI as a triage tool by examining outcomes in patients whose disposition from the Emergency Department differed from that predicted by the PSI. PSI scores were calculated by retrospective chart review for all adults with CAP presenting to the Emergency Department of a university medical center. Disposition was classified as consistent with the PSI when low-risk patients were discharged and high-risk patients were admitted. Charts of low-risk patients whose disposition was inconsistent with the PSI were abstracted for documentation of comorbidities contributing to the admission decision, as well as length of stay and level of care. There were 174 patients with CAP who met inclusion criteria, and 32% had a disposition inconsistent with the PSI. Eighty-six percent of the inconsistencies involved low-risk patients admitted to the hospital, and 41% of all low-risk patients with CAP were hospitalized. Hypoxia contributed to the decision to admit in 48% of these patients. Average length of stay was 5.2 days, and 78% of patients remained in the hospital > 48 h. Hypoxia was the most frequent factor contributing to admission of low-risk patients with CAP. Low-risk inpatients had a significant length of stay, suggesting that clinical judgment appropriately superseded the PSI in these cases.

Prognostic scoring systems: which one is best?

PURPOSE OF REVIEW

In the initial evaluation of patients with community-acquired pneumonia, a number of important assessments are made, including that of the severity of the illness. This assessment will determine the appropriate site of care, diagnostic work-up, and choice of empiric antibiotics. A number of severity assessment tools have been developed and some of the recent findings are reviewed.

RECENT FINDINGS

A number of studies of the efficacy of the individual scoring systems, as well as comparator studies, have been undertaken. A significant number of patients with community-acquired pneumonia in Pneumonia Severity Index classes I and II are admitted to hospital and several of these patients suffer complications. Clinical and social factors other than those contained in the scoring systems need to be taken into consideration when deciding about hospitalization of patients with community-acquired pneumonia. A number of studies of the efficacy of the various scoring systems in predicting 'severe pneumonia' have been undertaken, as well as studies of their accuracy in the sub-set of patients with pneumococcal infections and in the elderly.

SUMMARY

The various scoring systems have reasonable sensitivity and specificity and their own strengths and weaknesses, but should always be used in association with good clinical judgment.