Etiology of community-acquired pneumonia: impact of age, comorbidity, and severity

The incidence and etiology of community-acquired pneumonia in fever outpatients

The purpose of this study was to analyze the incidence, etiology and clinical characteristics of community-acquired pneumonia (CAP) among outpatients with sore throat and/or cough, and thus to provide theoretical basis for timely and accurate diagnosis and treatment for CAP. We used chest X-rays for fever (a temperature greater than 37.58C) patients, who were recruited since 2007, presenting with sore throat and/or cough. The patients’ age, gender, days of fever, respiratory symptoms (e.g. cough and sputum), peripheral blood count and etiology (pathogens) of CAP were recorded. Of all the 6539 fever outpatients, those aged 10-39 and above 60 years old accounted for 61.0% and 15.6%, respectively. In total, 402 were diagnosed with CAP with an incidence rate of 6.1%. Among them, 38.1% were above 60 years old. The prevalence increased with age. Of the 402 CAP patients, 36.8% (148/402) presented no respiratory symptoms and 30.1% (121/402) had positive etiology. The top three pathogens were Mycoplasma pneumoniae (23.1%), Streptococcus pneumoniae (17.3%) and Haemophilus influenzae (9.1%). Among the 121 etiology-positive patients, 14 cases were mixed infections (at least one atypical pathogen). Nine cases were M. pneumoniae mixed with bacterial/virus infection, and five cases were Chlamydia pneumoniae mixed with other bacteria/ mycoplasma infection. We found that fever outpatients have a higher prevalence of CAP, which increases with age, i.e. older people are more susceptible to CAP. S. pneumoniae and H. influenzae are common pathogens in CAP; however, atypical pathogens, especially M. pneumoniae, remain the most common pathogens in CAP.

Proton pump inhibitor therapy predisposes to community-acquired Streptococcus pneumoniae pneumonia

BACKGROUND

The pathophysiological mechanisms which contribute to an increased risk of community-acquired pneumonia (CAP) in patients using proton pump inhibitors are not well established.

AIM

To examine differences in microbial etiology in patients with CAP between patients with and without proton pump inhibitor (PPI) therapy and its possible impact on disease severity.

METHODS

All individuals consulting the emergency care unit were prospectively registered and underwent chest radiography. Sputum, urine, nose-throat swabs and blood samples were obtained for microbial evaluation. We evaluated the association between use of proton pump inhibitors, etiology of CAP and severity of illness with multivariate regression analysis.

RESULTS

The final cohort comprised 463 patients, 29% using proton pump inhibitors (PPIs). Pathogens regarded as oropharyngeal flora were more common in CAP patients using PPI therapy compared to those who did not (adjusted OR: 2.0; 95% CI: 1.22-3.72). Patients using proton pump inhibitors more frequently had an infection with Streptococcus pneumoniae (28% vs. 14%) and less frequently with Coxiella burnetii (8% vs. 19%) compared to nonuser of PPI. Adjusted for baseline differences, the risk of PPI users being infected with S. pneumonia was 2.23 times (95% CI: 1.28-3.75) higher compared to patients without PPI's. No risk between PPI use and any other microbial pathogen was found. There was no difference in severity of CAP between patients with and without using PPI therapy.

CONCLUSIONS

Proton pump inhibitor therapy was associated with an approximately 2-fold increased risk to develop community-acquired pneumonia possibly as a result of S. pneumoniae infection.

Comorbidities as a driver of the excess costs of community-acquired pneumonia in U.S. commercially-insured working age adults

BACKGROUND

Adults with certain comorbid conditions have a higher risk of pneumonia than the overall population. If treatment of pneumonia is more costly in certain predictable situations, this would affect the value proposition of populations for pneumonia prevention. We estimate the economic impact of community-acquired pneumonia (CAP) for adults with asthma, diabetes, chronic obstructive pulmonary disease (COPD) and congestive heart failure (CHF) in a large U.S. commercially-insured working age population.

METHODS

Data sources consisted of 2003 through 2007 Thomson Reuters MarketScan Commercial Claims and Encounters and Thomson Reuters Health Productivity and Management (HPM) databases. Pneumonia episodes and selected comorbidities were identified by ICD-9-CM diagnosis codes. By propensity score matching, controls were identified for pneumonia patients. Excess direct medical costs and excess productivity cost were estimated by generalized linear models (GLM).

RESULTS

We identified 402,831 patients with CAP between 2003 through 2007, with 25,560, 32,677, 16,343, and 5,062 episodes occurring in patients with asthma, diabetes, COPD and CHF, respectively. Mean excess costs (and standard error, SE) of CAP were $14,429 (SE=44) overall. Mean excess costs by comorbidity subgroup were lowest for asthma ($13,307 (SE=123)), followed by diabetes ($21,395 (SE=171)) and COPD ($23,493 (SE=197)); mean excess costs were highest for patients with CHF ($34,436 (SE=549)). On average, indirect costs comprised 21% of total excess costs, ranging from 8% for CHF patients to 27% for COPD patients.

CONCLUSIONS

Compared to patients without asthma, diabetes, COPD, or CHF, the excess cost of CAP is nearly twice as high for patients with diabetes and COPD and nearly three times as high for patients with CHF. Indirect costs made up a significant but varying portion of excess CAP costs. Returns on prevention of pneumonia would therefore be higher in adults with these comorbidities.

Pneumococcal infections and adult with risk factors

Streptococcus pneumoniae is an important bacterium in humans, and is a cause of upper and lower respiratory tract infections, meningitis, bacteremia, and/or invasive infections. An analysis of literature allows identifying the main risk factors; spleen dysfunctions, sickle cell anemia, alcohol abuse, chronic liver disease, cirrhosis, ischemic cardiac diseases, congestive cardiac failure, diabetes mellitus, obesity, chronic lung disease, immunodeficient patients including HIV infection, and old age. S. pneumoniae infections are more frequent and more severe in these patients. The pathophysiological mechanisms involved may be associated. These populations at risk should receive anti-pneumococcal vaccination. The availability of a 13 valent conjugate vaccine for adult opens new perspectives, but its clinical effectiveness needs to be proved for these patients at risk.

Clinical differences between influenza A (H1N1) virus and respiratory infection between the two waves in 2009 and 2010

Background

The purpose of the present retrospective study was to examine the clinical differences between patients hospitalized with H1N1 virus and those hospitalized with nonvirus respiratory tract infection in 2009 and 2010.

Methods

Adult patient data were collected from three tertiary hospital centers. Real-time reverse transcriptase polymerase chain reaction testing was used to confirm the diagnosis. We included 106 H1N1-positive patients (52 from 2009 and 54 from 2010). These data were compared with those from 108 patients with H1N1-negative respiratory tract infection (51 patients from 2009 and 57 from 2010).

Results

In 2009, the mean age was 36.4 years for H1N1-positive patients versus 46.4 years for H1N1-negative patients, and mean body mass index (BMI) was 26.4 kg/m² patients and 28.1 kg/m², respectively. In 2009, seven patients required intubation, six of whom were H1N1-positive. In 2010, the mean age was 43.8 years for H1N1-positive patients versus 60.2 years for H1N1-negative patients, and mean BMI was 32.3 kg/m² and 26.9 kg/m², respectively. In 2010, six patients required intubation, three of whom were H1N1-positive. Abnormal chest x-ray findings were found significantly more frequently in H1N1-negative patients than in H1N1-positive patients.

Conclusion

In comparison with 2009, H1N1-positive patients in 2010 were older, were more likely to be obese, and had more severe clinical and laboratory perturbations. However, this did not affect their outcomes. H1N1-negative patients were older in comparison with those who were H1N1-positive, and had more severe clinical and laboratory perturbations.

Optimizing Treatment Outcomes in Severe Community-Acquired Pneumonia

Severe community-acquired pneumonia (CAP) is a life-threatening condition that requires intensive care unit (ICU) admission. Clinical presentation is characterized by the presence of respiratory failure, severe sepsis, or septic shock. Severe CAP accounts for approximately 5-35% of hospital-treated cases of pneumonia with the majority of patients having underlying comorbidities. The most common pathogens associated with this disease are Streptococcus pneumoniae, Legionella spp., Haemophilus influenzae, and Gram-negative enteric rods. Microbial investigation is probably helpful in the individual case but is likely to be more useful for defining local antimicrobial policies. The early and rapid initiation of empiric antimicrobial treatment is critical for a favorable outcome. It should include intravenous beta-lactam along with either a macrolide or a fluoroquinolone. Modifications of this basic regimen should be considered in the presence of distinct comorbid conditions and risk factors for specific pathogens. Other promising nonantimicrobial new therapies are currently being investigated. The assessment of severity of CAP helps physicians to identify patients who could be managed safely in an ambulatory setting. It may also play a crucial role in decisions about length of hospital stay and time of switching to oral antimicrobial therapy in different groups at risk. The most important adverse prognostic factors include advancing age, male sex, poor health of patient, acute respiratory failure, severe sepsis, septic shock, progressive radiographic course, bacteremia, signs of disease progression within the first 48-72 hours, and the presence of several different pathogens such as S. pneumoniae, Staphylococcus aureus, Gram-negative enteric bacilli, or Pseudomonas aeruginosa. However, some important topics of severity assessment remain controversial, including the definition of severe CAP. Prediction rules for complications or death from CAP, although far from perfect, should identify the majority of patients with severe CAP and be used to support decision-making by the physician. They may also contribute to the evaluation of processes and outcomes of care for patients with CAP.

Laboratory methods for determining pneumonia etiology in children

Laboratory diagnostics are a core component of any pneumonia etiology study. Recent advances in diagnostic technology have introduced newer methods that have greatly improved the ability to identify respiratory pathogens. However, determining the microbial etiology of pneumonia remains a challenge, especially in children. This is largely because of the inconsistent use of assays between studies, difficulties in specimen collection, and problems in interpreting the presence of pathogens as being causally related to the pneumonia event. The laboratory testing strategy for the Pneumonia Etiology Research for Child Health (PERCH) study aims to incorporate a broad range of diagnostic testing that will be standardized across the 7 participating sites. We describe the current status of laboratory diagnostics for pneumonia and the PERCH approach for specimen testing. Pneumonia diagnostics are evolving, and it is also a priority of PERCH to collect and archive specimens for future testing by promising diagnostic methods that are currently under development.

Seroepidemiology of human bocavirus infection in Jamaica

BACKGROUND

Human bocavirus (HBoV) is a newly identified human parvovirus. HBoV is associated with upper and lower respiratory tract infections and gastroenteritis in children. Little is known about the seroepidemiology of HBoV in populations in the Caribbean.

METHODS

In a cross-sectional study conducted at the University Hospital of the West Indies in Kingston, Jamaica, 287 blood samples were collected from pediatric patients and tested for the presence of HBoV-specific antibody using a virus-like-particle based enzyme-linked immunosorbent assay (ELISA).

RESULTS

HBoV-specific antibodies were found to be present in 220/287 (76.7%) of samples collected from the pediatric population. Seroprevalence of HBoV was highest in those ≥2 years old. The seroepidemiological profile suggests that most children are exposed to HBoV during the first two years of life in Jamaica.

CONCLUSION

HBoV infection is common in children in Jamaica. HBoV seroprevalence rates in the Caribbean are similar to those previously reported in other areas of the world.

Bacterial co-infection with H1N1 infection in patients admitted with community acquired pneumonia

BACKGROUND

Bacterial co-infection is an important contributor to morbidity and mortality during influenza pandemics .We investigated the incidence, risk factors and outcome of patients with influenza A H1N1 pneumonia and bacterial co-infection.

METHODS

Prospective observational study of consecutive hospitalized patients with influenza A H1N1 virus and community-acquired pneumonia (CAP). We compared cases with and without bacterial co-infection.

RESULTS

The incidence of influenza A H1N1 infection in CAP during the pandemic period was 19% (n, 667). We studied 128 patients; 42(33%) had bacterial co-infection. The most frequently isolated bacterial pathogens were Streptococcus pneumoniae (26, 62%) and Pseudomonas aeruginosa (6, 14%). Predictors for bacterial co-infection were chronic obstructive pulmonary disease (COPD) and increase of platelets count. The hospital mortality was 9%. Factors associated with mortality were age ≥ 65 years, presence of septic shock and the need for mechanical ventilation. Although patients with bacterial co-infection presented with higher Pneumonia Severity Index risk class, hospital mortality was similar to patients without bacterial co-infection (7% vs. 11%, respectively, p = 0.54).

CONCLUSION

Bacterial co-infection was frequent in influenza A H1N1 pneumonia, with COPD and increased platelet count as the main predictors. Although associated with higher severe scales at admission, bacterial co-infection did not influence mortality of these patients.

Influenza and community-acquired pneumonia interactions: the impact of order and time of infection on population patterns

Discoveries made during the 1918 influenza A pandemic and reports of severe disease associated with coinfection during the 2009 hemagglutinin type 1 and neuraminidase type 1 (commonly known as H1N1 or swine flu) pandemic have renewed interest in the role of coinfection in disease pathogenesis. The authors assessed how various timings of coinfection with influenza virus and pneumonia-causing bacteria could affect the severity of illness at multiple levels of interaction, including the biologic and population levels. Animal studies most strongly support a single pathway of coinfection with influenza inoculation occurring approximately 7 days before inoculation with Streptococcus pneumoniae, but less-examined pathways of infection also may be important for human disease. The authors discussed the implications of each pathway for disease prevention and what they would expect to see at the population level if there were sufficient data available. Lastly, the authors identified crucial gaps in the study of timing of coinfection and proposed related research questions.

Adenovirus pneumonia in an immunocompetent adult

Adenovirus pneumonias are reported relatively commonly in pediatric or immunocompromised patients, but the clinical presentation of adenovirus pneumonia in immunocompetent hosts is not well known. We treated an immunocompetent 42-year-old man with mild adenovirus pneumonia following pharyngitis and conjunctivitis. Diagnosis was established on the basis of chest radiologic findings, detection of adenovirus type 7 DNA by PCR assay in material obtained from bronchoalveolar lavage (BAL), and a greater than fourfold rise in adenovirus-specific antibody titers during the course of illness. The patient's self-limiting symptoms improved within 2 weeks, and chest radiologic findings improved within 4 weeks. PCR assay of material obtained by BAL was useful for the rapid diagnosis of adenovirus pneumonia.

Epidemiology and management of common pulmonary diseases in older persons

Pulmonary disease prevalence increases with age and contributes to morbidity and mortality in older patients. Dyspnea in older patients is often ascribed to multiple etiologies such as medical comorbidities and deconditioning. Common pulmonary disorders are frequently overlooked as contributors to dyspnea in older patients. In addition to negative impacts on morbidity and mortality, quality of life is reduced in older patients with uncontrolled, undertreated pulmonary symptoms. The purpose of this review is to discuss the epidemiology of common pulmonary diseases, namely pneumonia, chronic obstructive pulmonary disease, asthma, lung cancer, and idiopathic pulmonary fibrosis in older patients. We will review common clinical presentations for these diseases and highlight differences between younger and older patients. We will also briefly discuss risk factors, treatment, and mortality associated with these diseases. Finally, we will address the relationship between comorbidities, pulmonary symptoms, and quality of life in older patients with pulmonary diseases.

Guidelines for the management of adult lower respiratory tract infections--summary

This document is an update of Guidelines published in 2005 and now includes scientific publications through to May 2010. It provides evidence-based recommendations for the most common management questions occurring in routine clinical practice in the management of adult patients with LRTI. Topics include management outside hospital, management inside hospital (including community-acquired pneumonia (CAP), acute exacerbations of COPD (AECOPD), acute exacerbations of bronchiectasis) and prevention. The target audience for the Guideline is thus all those whose routine practice includes the management of adult LRTI.

Successful treatment of fulminant community-acquired Pseudomonas aeruginosa necrotizing pneumonia in a previously healthy young man

This report presents a case of fulminant community-acquired Pseudomonas aeruginosa necrotizing pneumonia in a previously healthy young man, including an analysis of the virulence of the P.aeruginosa isolated from the patient. The patient was successfully treated with intensive care and antibiotic treatment. This study analyzed the pathogenicity of the isolated strain both in vivo (using a mouse pneumonia model) and in vitro (using biofilm production), but could not explain how an otherwise healthy young man developed such severe community-acquired P.aeruginosa pneumonia. Although rare in community-acquired pneumonia, P.aeruginosa infection should be considered in patients with severe rapidly progressive pneumonia.

Severe pneumococcal community-acquired pneumonia admitted to medical Tunisian ICU

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia (CAP). There are no available data about this disease in Tunisian intensive care patients. The objective of this study is to describe the clinical and microbiological features of pneumococcal CAP and determine the prognostic factors. This is a retrospective cohort study of all pneumococcal CAP cases hospitalized in the medical intensive care unit (ICU) of Hospital A. Mami of Ariana (Tunisia) between January 1999 and August 2008. Included were 132 patients (mean age, 49.5 years; 82.6% males); 30 patients had received antimicrobial treatment before hospital admission. The mean of the Simplified Acute Physiology Score II was 32.9. All patients had an acute respiratory failure; 34 patients (25.8%) had pneumococcal bacteremic CAP. Among the isolated strains, 125 antimicrobial susceptibility tests were performed. The use of the new Clinical and Laboratory Standards Institute breakpoints for susceptibility when testing penicillin against S. pneumoniae showed that all isolated strains were susceptible to penicillin. The mortality rate was 25%. The need of mechanical ventilation at admission [odds ratio (OR), 3.4; 95% confidence interval (CI), 1.67-6.94; P = 0.001), Sepsis-related Organ Failure Assessment (SOFA) score at admission ≥4 (OR, 3.1; 95% CI, 1.56-6.13; P = 0.001), and serum creatinine at admission ≥102 μmol/l (OR, 1.8; 95% CI, 1.02-3.17; P = 0.043) were independent factors related to ICU mortality. In conclusion, pneumococcal CAP requiring hospitalization in the ICU is associated with high mortality. All isolated stains were susceptible to penicillin.

Guidelines for the management of adult lower respiratory tract infections--full version

This document is an update of Guidelines published in 2005 and now includes scientific publications through to May 2010. It provides evidence-based recommendations for the most common management questions occurring in routine clinical practice in the management of adult patients with LRTI. Topics include management outside hospital, management inside hospital (including community-acquired pneumonia (CAP), acute exacerbations of COPD (AECOPD), acute exacerbations of bronchiectasis) and prevention. Background sections and graded evidence tables are also included. The target audience for the Guideline is thus all those whose routine practice includes the management of adult LRTI.

Macrophage phagocytosis: effects of environmental pollutants, alcohol, cigarette smoke, and other external factors

The ability of a pathogen to evade host immunity successfully, in contrast to the host's capacity to defend itself against a foreign invader, is a complex struggle, in which eradication of infection is dictated by a robust immunologic response. Often, there are external factors that can alter the outcome by tipping the scale to benefit pathogen establishment rather than resolution by the host's defense system. These external sources, such a cigarettes, alcohol, or environmental pollutants, can negatively influence the effectiveness of the immune system's response to a pathogen. The observed suppression of immune function can be attributed to dysregulated cytokine and chemokine production, the loss of migratory potential, or the inability to phagocytose pathogens by immune cells. This review will focus on the mechanisms involved during the toxin-induced suppression of phagocytosis. The accumulated data support the importance of studying the mechanisms of phagocytosis following exposure to these factors, in that this effect alone cannot only leave the host susceptible to infection but also promote alterations in many other macrophage functions necessary for pathogen clearance and restoration of homeostasis.

Comparisons of clinical characters in patients with pneumococcal and Legionella pneumonia

BACKGROUND/PURPOSE

The etiology of pneumonia is usually unknown, but the availability of urinary pneumococcal and Legionella antigen tests can improve the diagnostic yield. Our aim was to provide clinical clues to help clinicians perform the appropriate urinary antigen tests.

METHODS

A retrospective study of patients admitted to the National Cheng Kung University Hospital between July 2006 and June 2008 was conducted. Patients aged over 18 years presenting with clinical symptoms and signs, radiological findings compatible with pneumonia, and a positive pneumococcal or Legionella pneumophila urinary antigen test, were included. Medical records were reviewed for data collection.

RESULTS

Overall, 55 adults with pneumonia, including 42 with pneumococcal pneumonia (PP) and 13 with Legionella pneumonia (LP), were enrolled. On admission, patients with PP tended to be older (73.5 years vs. 59.1 years; p=0.001), had lower body weights (52.0 kg vs. 69.7 kg; p < 0.001), more frequent respiratory symptoms (59.5%vs. 0%; p < 0.001), and lower systolic (123.0 mmHg vs. 141.0 mmHg; p=0.004) and diastolic blood pressures (68.3 mmHg vs. 81.7 mmHg; p=0.008), compared with patients with LP. However, those with LP had higher body temperatures (39.0°C vs. 37.5°C; p < 0.001), a higher incidence of relative bradycardia (45.5%vs. 0%; p < 0.001), diarrhea (15.4%vs. 0%; p= 0.053), and lower platelet counts (178.5 × 10(3)/mm(3)vs. 233.7 × 10(3)/mm(3); p= 0.026). Radiological findings showed that the major abnormality, lobar consolidation, was indistinguishable between LP and PP. The percentage of patients requiring intensive care (35.7%vs. 38.5%) or ventilator support (31%vs. 23.1%) and in-hospital crude mortality rates (9.5%vs. 7.7%) was similar in both groups.

CONCLUSION

Some clinical and laboratory characteristics may be regarded as important clues indicating the need for an appropriate urinary antigen test in patients with pneumonia.

Review Series: Old age: Pneumonia in old age

At the end of the 19th century William Osler noted key differences in the presentation of pneumonia in the elderly. His observational perspicuity has withstood the passage of time. The following article pays deference to this Canadian physician, summarizing not only differences in clinical presentation but also including an update on epidemiology, aetiology and management.

Correlations between computed tomography findings and clinical manifestations of Streptococcus pneumoniae pneumonia

PURPOSE

The aim of this study was to characterize the imaging features and compare computed tomography (CT) findings with clinical features of patients with Streptococcus pneumoniae pneumonia.

MATERIALS AND METHODS

We retrospectively reviewed 75 patients (44 men, 31 women; mean age 67 years) diagnosed with S. pneumoniae pneumonia who underwent chest CT scanning at our institution between January 2007 and August 2008. Diagnoses were based on detection of the S. pneumoniae antigen in urine.

RESULTS

Chest CT scans revealed abnormalities in all patients. The predominant opacity patterns were an airspace pneumonia pattern (48%) and a bronchopneumonia pattern (48%), followed by an interstitial pneumonia pattern (4%). Consolidation was observed most frequently (84%) followed by ground glass opacity (82.7%), bronchial wall thickening (61.3%), and centrilobular nodules (49.3%). Airway dilatation (21.6%), pleural effusion (33.3%), lymphadenopathy (34.8%), and pulmonary emphysema (21.3%) were also observed. Pulmonary emphysema was significantly less frequent in patients with the bronchopneumonia pattern than in those without (p = 0.007). The clinical features and CT findings did not differ significantly.

CONCLUSION

CT image analysis showed that patients with S. pneumoniae pneumonia exhibited the bronchopneumonia and airspace pneumonia patterns with equal frequency. Bronchopneumonia pattern was less common in patients with preexisting emphysema.

Severe community-acquired Enterobacter pneumonia: a plea for greater awareness of the concept of health-care-associated pneumonia

Background

Patients with Enterobacter community-acquired pneumonia (EnCAP) were admitted to our intensive care unit (ICU). Our primary aim was to describe them as few data are available on EnCAP. A comparison with CAP due to common and typical bacteria was performed.

Methods

Baseline clinical, biological and radiographic characteristics, criteria for health-care-associated pneumonia (HCAP) were compared between each case of EnCAP and thirty age-matched typical CAP cases. A univariate and multivariate logistic regression analysis was performed to determine factors independently associated with ENCAP. Their outcome was also compared.

Results

In comparison with CAP due to common bacteria, a lower leukocytosis and constant HCAP criteria were associated with EnCAP. Empiric antibiotic therapy was less effective in EnCAP (20%) than in typical CAP (97%) (p < 0.01). A delay in the initiation of appropriate antibiotic therapy (3.3 ± 1.6 vs. 1.2 ± 0.6 days; p < 0.01) and an increase in duration of mechanical ventilation (8.4 ± 5.2 vs. 4.0 ± 4.3 days; p = 0.01) and ICU stay were observed in EnCAP patients.

Conclusions

EnCAP is a severe infection which is more consistent with HCAP than with typical CAP. This retrospectively suggests that the application of HCAP guidelines should have improved EnCAP management.

Risk factors and severity scores in hospitalized patients with community-acquired pneumonia: prediction of severity and mortality

Morbidity and mortality in patients with moderate to severe community-acquired pneumonia (CAP) is a global problem, and CAP is a leading cause of death due to infectious diseases. Prompt initiation of expanded-spectrum antimicrobials is essential for the prevention of unnecessary mortality and complications in patients, particularly in the elderly and other at-risk populations, and the treatment decisions made by practitioners have important implications for healthcare systems when hospitalization is required. Empirical antimicrobial treatment and the appropriate management of CAP patients will initially require the proper assessment of severity and patient risk for increased mortality, as well as risk factors for difficult-to-treat bacteria. This review will examine risk factors and scoring systems that may be predictive of moderate to severe CAP, which is often linked to increased risk of mortality. Understanding and recognizing potential risk factors will allow practitioners to proactively identify patients at the highest risk for severe illness or complications, thereby, guiding site-of-care decisions, as well as the choices for empiric antibiotic regimens. The decision to hospitalize a patient with CAP should include not only a clinical perspective and laboratory and radiographic findings, but also at least one objective tool of risk assessment, all in combination with sound clinical judgment.

Viral pneumonia

About 200 million cases of viral community-acquired pneumonia occur every year-100 million in children and 100 million in adults. Molecular diagnostic tests have greatly increased our understanding of the role of viruses in pneumonia, and findings indicate that the incidence of viral pneumonia has been underestimated. In children, respiratory syncytial virus, rhinovirus, human metapneumovirus, human bocavirus, and parainfluenza viruses are the agents identified most frequently in both developed and developing countries. Dual viral infections are common, and a third of children have evidence of viral-bacterial co-infection. In adults, viruses are the putative causative agents in a third of cases of community-acquired pneumonia, in particular influenza viruses, rhinoviruses, and coronaviruses. Bacteria continue to have a predominant role in adults with pneumonia. Presence of viral epidemics in the community, patient's age, speed of onset of illness, symptoms, biomarkers, radiographic changes, and response to treatment can help differentiate viral from bacterial pneumonia. However, no clinical algorithm exists that will distinguish clearly the cause of pneumonia. No clear consensus has been reached about whether patients with obvious viral community-acquired pneumonia need to be treated with antibiotics. Apart from neuraminidase inhibitors for pneumonia caused by influenza viruses, there is no clear role for use of specific antivirals to treat viral community-acquired pneumonia. Influenza vaccines are the only available specific preventive measures. Further studies are needed to better understand the cause and pathogenesis of community-acquired pneumonia. Furthermore, regional differences in cause of pneumonia should be investigated, in particular to obtain more data from developing countries.

Healthcare-associated pneumonia among hospitalized patients in a Korean tertiary hospital

Background

Healthcare-associated pneumonia (HCAP) has more similarities to nosocomial pneumonia than to community-acquired pneumonia (CAP). However, there have only been a few epidemiological studies of HCAP in South Korea. We aimed to determine the differences between HCAP and CAP in terms of clinical features, pathogens, and outcomes, and to clarify approaches for initial antibiotic management.

Methods

We conducted a retrospective, observational study of 527 patients with HCAP or CAP who were hospitalized at Severance Hospital in South Korea between January and December 2008.

Results

Of these patients, 231 (43.8%) had HCAP, and 296 (56.2%) had CAP. Potentially drug-resistant (PDR) bacteria were more frequently isolated in HCAP than CAP (12.6% vs. 4.7%; P = 0.001), especially in the low-risk group of the PSI classes (41.2% vs. 13.9%; P = 0.027). In-hospital mortality was higher for HCAP than CAP patients (28.1% vs. 10.8%, P < 0.001), especially in the low-risk group of PSI classes (16.4% vs. 3.1%; P = 0.001). Moreover, tube feeding and prior hospitalization with antibiotic treatment within 90 days of pneumonia onset were significant risk factors for PDR pathogens, with odds ratios of 14.94 (95% CI 4.62-48.31; P < 0.001) and 2.68 (95% CI 1.32-5.46; P = 0.007), respectively.

Conclusions

For HCAP patients with different backgrounds, various pathogens and antibiotic resistance of should be considered, and careful selection of patients requiring broad-spectrum antibiotics is important when physicians start initial antibiotic treatments.

Improvement of CRB-65 as a prognostic scoring system in adult patients with bacteraemic pneumococcal pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) is the leading cause of hospitalization among infectious diseases, and is mainly caused by Streptococcus pneumoniae. Modifications were tested to improve the accuracy of CRB-65 as a simple but useful bedside scoring system, and to compare it with 3 established severity scoring systems (PSI, CURB-65 and CRB-65) to predict 30-day mortality in bacteraemic pneumococcal CAP.

METHODS

A retrospective analysis was performed on data from 375 adult patients with bacteraemic pneumococcal pneumonia. Mortality, sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic (ROC) curve were calculated for stratifications of the PSI, CURB-65 and CRB-65. The prognostic accuracy after addition of underlying disease and/or a peripheral oxygen saturation (SaO₂) < 90% was evaluated (DS CRB-65).

RESULTS

The mean age of the patients was 61.5 y, and the 30-day mortality was 9%. Coexisting conditions defined according to the pneumonia severity index (PSI) rule (malignancy, liver, cerebrovascular, and renal disease and congestive heart failure, p = 0.006) and SaO₂ < 90% (p < 0.0001) were independently associated with mortality. By adding these variables, the area under the ROC curve of CRB-65 increased from 0.77 (95% confidence interval (CI) 0.66-0.84) to 0.83 (95% CI 0.73-0.89) (p = 0.01), similar to that of PSI (0.84) and CURB-65 (0.81).

CONCLUSIONS

Modification of CRB-65 with the addition of 1 point for the presence of any underlying disease according to the PSI rule, and with 1 point if SaO₂ was < 90%, increased its prognostic accuracy in bacteraemic pneumococcal pneumonia with retained independence of laboratory data. The modified CRB-65 may have potential use in the assessment of prognosis in patients with CAP.

Community-acquired pneumonia in patients with liver cirrhosis: clinical features, outcomes, and usefulness of severity scores

We performed an observational analysis of a prospective cohort of nonimmunocompromised hospitalized adults with community-acquired pneumonia (CAP) to determine the epidemiology, clinical features, and outcomes of patients with liver cirrhosis. We also analyzed the prognostic value of several severity scores. Of 3420 CAP episodes, 90 occurred in patients with liver cirrhosis. The median value of the Model for End-Stage Liver Disease (MELD) was 14 (range, 6-36). On the Child-Pugh (CP) score, 56% of patients were defined as grade B and 22% as grade C. Patients with liver cirrhosis were younger (61.8 vs. 66.8 yr; p = 0.001) than patients without cirrhosis, more frequently presented impaired consciousness at admission (33% vs. 14%; p < 0.001) and septic shock (13% vs. 6%; p = 0.011), and were more commonly classified in high-risk Pneumonia Severity Index (PSI) classes (classes IV-V) (74% vs. 58%; p = 0.002). Streptococcus pneumoniae (47% vs. 33%; p = 0.009) and Pseudomonas aeruginosa (4.4% vs. 0.9%; p = 0.001) were more frequently documented in patients with cirrhosis. Bacteremia was also more common in these patients (22% vs. 13%; p = 0.023). Areas under the curve (AUCs) from disease-specific scores (MELD, CP, PSI, and CURB-65 [confusion, urea, respiratory rate, blood pressure, and age ≥65 yr]) were comparable in predicting severe disease (30-d mortality and intensive care unit [ICU] admission). A new score based on MELD, multilobar pneumonia, and septic shock at admission (MELD-CAP) had an AUC of 0.945 (95% confidence interval [CI], 0.872-0.983) for predicting severe disease and was significantly different from other scores. Early (5.6% vs. 2.1%; p = 0.048) and overall (14.4% vs. 7.4%; p < 0.024) mortality rates were higher in cirrhotic patients than in patients without cirrhosis. Factors associated with mortality were impaired consciousness, multilobar pneumonia, ascites, acute renal failure, bacteremia, ICU admission, and MELD score. Among the severity scores, MELD-CAP was the only score associated with severe disease (odds ratio [OR], 1.33; 95% CI, 1.09-1.52) and mortality (OR, 1.21; 95% CI, 1.03-1.42). In conclusion, CAP in patients with liver cirrhosis presents a distinctive clinical picture and is associated with higher mortality than is found in patients without cirrhosis. The severity of hepatic dysfunction plays an important role in the development of adverse events. Cirrhosis-specific scores may be useful for predicting and stratifying cirrhotic patients with CAP who have a high risk of severe disease.

Epidemiology, clinical features and outcomes of pneumonia in patients with chronic kidney disease

BACKGROUND

Although infection remains among the most common causes of morbidity and mortality in patients with chronic kidney disease (CKD), data on epidemiology, clinical features and outcomes of pneumonia in this population are scarce.

METHODS

Observational analysis of a prospective cohort of hospitalized adults with pneumonia, between 13 February 1995 and 30 April 2010, in a tertiary teaching hospital. CKD patients, defined as patients with a baseline glomerular filtration rate <60 mL/min/1.73 m(2), were compared with non-CKD patients.

RESULTS

During the study period, 3800 patients with pneumonia required hospitalization. Two-hundred and three (5.3%) patients had CKD, of whom 46 were on dialysis therapy. Patients with CKD were older (77 versus 70 years; P < 0.001), were more likely to have comorbidities (82.3 versus 63.3%; P < 0.001) and more commonly classified into high-risk pneumonia severity index classes (89.6 versus 57%; P < 0.001) than were the remaining patients. Streptococcus pneumoniae was the most frequent pathogen (28.1 versus 34.7%; P = 0.05). Mortality was higher in patients with CKD (15.8 versus 8.3%; P < 0.001). Among CKD patients, age [+1 year increase; adjusted odds ratio, 1.25; 95% confidence interval (CI) 1.07-1.46] and cardiac complications during hospitalization (adjusted odds ratio, 9.23; 95% CI 1.39-61.1) were found to be independent risk factors for mortality, whereas prior pneumococcal vaccination (adjusted odds ratio, 0.05; 95% CI 0.005-0.69) and leukocytosis at hospital admission (adjusted odds ratio, 0.10; 95% CI 0.01-0.64) were protective factors.

CONCLUSIONS

Pneumonia is a serious complication in CKD patients. Independent factors for mortality are older age and cardiac complications, whereas prior pneumococcal vaccination and leucokytosis at hospital admission are protective factors. These findings should encourage physicians to increase pneumococcal vaccine coverage among CKD patients.

The blind nasotracheal aspiration method is not a useful tool for pathogen detection of pneumonia in children

Background

Acute lower respiratory infection (ALRI) is a major cause of hospitalization for children in China, while the etiological diagnosis of ALRI remains a challenge. This study was performed to evaluate the utility of the blind Nasotracheal aspiration (NTA) in the pathogen detection in ALRI through an evaluation of the test's specificity.

Methodology/Principal Findings

A hospital-based study of children ≤3 years was carried out from March 2006 through March 2007 in Suzhou University Affiliated Children's Hospital, including 379 cases with ALRI from the respiratory wards, and 394 controls receiving elective surgery. Nasopharyngeal swabs (NPS) and NTA specimens were taken on admission. S. pneumoniae was isolated from 10.3% of NTA samples from ALRI children, H. influenzae from 15.3%, and M. catarrhalis from 4.7%. The false positive rate—the strains from NTA in control group children—was 8.4% (95% CI: 5.8%–11.4%) for S. pneumoniae, 27.2% (95% CI: 22.7–31.5%) for H. influenzae, and 22.1% (95% CI: 18.0%–26.2%) for M. catarrhalis. The agreement between NPS and NTA in the control group was over 70%.

Conclusion/Significance

The blind NTA test is not a useful test for etiologic diagnosis of ALRI.

Q fever in Japan: an update review

As neglected zoonosis for many years, Q fever is now ubiquitous in Japan. Similarly to elsewhere in the world, domestic animals are considered to be important reservoirs of the causal agent, Coxiella burnetii, a resistant intracellular bacterium. Infected animals shed bacteria in milk, feces, urine, vaginal mucous and birth products. Inhalation of bacteria present in the environment is the main route of animal and human infection. Shedding of C. burnetii in milk by domestic ruminants has a very limited impact as raw milk is seldom ingested by the Japanese population. The clinical expression of Q fever in Japan is similar to its clinical expression elsewhere. However clinical cases in children are more frequently reported in this country. Moreover, C. burnetii is specified as one of the causative organisms of atypical pneumonia in the Japanese Respiratory Society Guideline for the management of community-acquired pneumonia. In Japan, C. burnetii isolates are associated with acute illness and are mainly of moderate to low virulence. Cats are considered a significant source of C. burnetii responsible for human outbreaks in association with the presence of infected parturient cats. Since its recognition as a reportable disease in 1999, 7-46 clinical cases of Q fever have been reported by year. The epidemiology of Q fever in Japan remains to be elucidated and the exact modes of transmission are still unproven. Important further research is necessary to improve knowledge of the disease itself, the endogenous hosts and reservoirs, and the epidemiological cycle of coxiellosis in Japan.

Factors associated with the outcome of life-threatening necrotizing pneumonia due to community-acquired Staphylococcus aureus in adult and adolescent patients

BACKGROUND

Although community-acquired Staphylococcus aureus pneumonia with highly virulent Panton-Valentine leukocidin (PVL)-positive strains, a severe disease with significant lethality, is rare, especially in adult and adolescent patients, recent reports highlight that these infections are on the rise.

OBJECTIVES

To describe the demographic and clinical features of reported cases of life-threatening community-acquired S. aureus pneumonia with usually PVL-positive strains in adult and adolescent patients, to evaluate the variables related to death, and to select a more appropriate antimicrobial treatment for this potentially deadly disease.

METHODS

We summarized all of the 92 reported cases and our case. The effect of 5 variables on mortality was measured using logistic regression.

RESULTS

S. aureus community-acquired pneumonia (CAP) with usually PVL-positive strains is a severe disease with significant lethality, i.e. 42.9%; a short duration of the time from the onset of symptoms to death, i.e. 5.5 ± 10.1 days, and prolonged hospital admissions, i.e. 33.2 ± 29.5 days. Seventy-three cases have been tested for the gene for PVL, and 71 strains have been found to carry the PVL gene. Logistic regression analysis showed that leucopenia (p = 0.002), influenza-like symptoms or laboratory-confirmed influenza (p = 0.011), and hemoptysis (p = 0.024) were the factors associated with death. Antibiotic therapies inhibiting toxin production were associated with an improved outcome in these cases (p = 0.007).

CONCLUSIONS

Physicians should pay special attention to those patients who acquired severe CAP during influenza season and have flu-like symptoms, hemoptysis, and leucopenia, and they should consider S. aureus more frequently among the possible pathogens of severe CAP. Empiric therapy for severe CAP with this distinct clinical picture should include coverage for S. aureus. Targeted treatment with antimicrobials inhibiting toxin production appears to be a more appropriate selection.

Pneumonia in older people

The incidence of pneumonia is higher in older than younger people, due to both an increase in factors facilitating entry of infectious agents into the lungs, and attenuated functioning of the immune system. Classic features of presentation of pneumonia may be absent. The most common signs of pneumonia in old age are tachypnoea and tachycardia. Aetiology is established in only 50% of older patients. The empirical treatment of community-aquired pneumonia (CAP) should be aimed at its most common cause,Streptococcus pneumoniae. The empirical treatment of health care-associated pneumonia (HCAP) should be targeted at Gram-negative agents. Choice of antibiotic must include consideration of potential drug interactions.

Aetiology of community-acquired pneumonia in hospitalized adult patients in New Caledonia

OBJECTIVE

To describe the aetiology of community-acquired pneumonia (CAP) in hospitalized adult patients in New Caledonia, a French archipelago in the South Pacific.

METHODS

Confirmed CAP patients (n=137) were enrolled prospectively. Pathogens were detected by culture, molecular methods, serology on paired sera, immunofluorescence on nasopharyngeal swabs and antigen detection in urine.

RESULTS

The aetiology of CAP was determined in 82 of 137 cases (59.8%), of which 31 exhibited two or more pathogens (37.8%). Hundred and seventeen pathogens were detected: Streptococcus pneumoniae was the most common one (41.0%), followed by influenza virus A (22.1%) and Haemophilus influenzae (10.2%). The frequency of atypical bacteria was low (6.0%). The most frequent and significant coinfection was S. pneumoniae with influenza A virus (P=0.004). Influenza virus was detected from nasopharyngeal swabs in four patients (15.4% of patients tested for influenza) and by PCR from pulmonary specimens in 15 patients (57.7%). CONCLUSIONS : Pneumoniae is the leading cause of CAP in New Caledonian adults. Viral-bacterial co-infections involving S. pneumoniae and influenza virus are very common during the winter. Such adult patients hospitalized with CAP are a clear sentinel group for surveillance of influenza. Vaccination against influenza and S. pneumoniae should be strengthened when risk factors are identified.

Human rhinovirus C: a newly discovered human rhinovirus species

Although often ignored, human rhinoviruses (HRVs) are the most frequent causes of respiratory tract infections (RTIs). A group of closely related novel rhinoviruses have recently been discovered. Based on their unique phylogenetic position and distinct genomic features, they are classified as a separate species, HRV-C. After their discovery, HRV-C viruses have been detected in patients worldwide, with a reported prevalence of 1.4-30.9% among tested specimens. This suggests that the species contribute to a significant proportion of RTIs that were unrecognized in the past. HRV-C is also the predominant HRV species, often with a higher detection rate than that of the two previously known species, HRV-A and HRV-B. HRV-C infections appear to peak in fall or winter in most temperate or subtropical countries, but may predominate in the rainy season in the tropics. In children, HRV-C is often associated with upper RTIs, with asthma exacerbation and wheezing episodes being common complications. The virus has also been detected in children with bronchitis, bronchiolitis, pneumonia, otitis media, sinusitis and systemic infections complicated by pericarditis. As for adults, HRV-C has been associated with more severe disease such as pneumonia and exacerbation of chronic obstructive pulmonary disease. However, larger clinical studies with asymptomatic controls are required to better define the significance of HRV-C infection in the adult population. On the basis of VP4 sequence analysis, a potential distinct subgroup within HRV-C has also been identified, although more complete genome sequences are needed to better define the genetic diversity of HRV-C.

Efficacy and safety of nemonoxacin versus levofloxacin for community-acquired pneumonia

Nemonoxacin, a novel nonfluorinated quinolone, exhibits potent in vitro and in vivo activities against community-acquired pneumonia (CAP) pathogens, including multidrug-resistant Streptococcus pneumoniae. Patients with mild to moderate CAP (n = 265) were randomized to receive oral nemonoxacin (750 mg or 500 mg) or levofloxacin (500 mg) once daily for 7 days. Clinical responses were determined at the test-of-cure visit in intent-to-treat (ITT), clinical per protocol (PPc), evaluable-ITT, and evaluable-PPc populations. The clinical cure rates for 750 mg nemonoxacin, 500 mg nemonoxacin, and levofloxacin were 89.9%, 87.0%, and 91.1%, respectively, in the evaluable-ITT population; 91.7%, 87.7%, and 90.3%, respectively, in the evaluable-PPc population; 82.6%, 75.3%, and 80.0%, respectively, in the ITT population; and 83.5%, 78.0%, and 82.3%, respectively, in the PPc population. Noninferiority to levofloxacin was demonstrated in both the 750-mg and 500-mg nemonoxacin groups for the evaluable-ITT and evaluable-PPc populations, and also in the 750 mg nemonoxacin group for the ITT and PPc populations. Overall bacteriological success rates were high for all treatment groups in the evaluable-bacteriological ITT population (90.2% in the 750 mg nemonoxacin group, 84.8% in the 500 mg nemonoxacin group, and 92.0% in the levofloxacin group). All three treatments were well tolerated, and no drug-related serious adverse events were observed. Overall, oral nemonoxacin (both 750 mg and 500 mg) administered for 7 days resulted in high clinical and bacteriological success rates in CAP patients. Further, good tolerability and excellent activity against common causative pathogens were demonstrated. Nemonoxacin (750 mg and 500 mg) once daily is as effective and safe as levofloxacin (500 mg) once daily for the treatment of CAP.

Legionnaires disease in cannabis smokers

Tobacco smoking is a well-recognized risk factor for Legionnaires disease. However, it may be potentiated by cannabis use, as there is strong evidence that Δ(9)-tetrahydrocannabinol impairs immune functions in vitro and in vivo. We report herein two out of three cases of severe Legionnaires disease in three men with no overt comorbid illnesses, aged 38, 28, and 48 years, respectively. All of them were heavy cigarette and cannabis smokers.

Community-acquired pneumonia in the elderly

BACKGROUND

Community-acquired pneumonia (CAP) is a frequent cause of hospitalization and death among the elderly.

OBJECTIVE

This article reviews information on CAP among the elderly, including age-related changes, predisposing risk factors, causes, treatment strategies, and prevention.

METHODS

Searches of MEDLINE (January 1990-November 2009), International Pharmaceutical Abstracts (January 1990-November 2009), and Google Scholar were conducted using the terms community-acquired pneumonia, pneumonia, treatment guidelines, and elderly. Additional publications were found by searching the reference lists of the identified articles. Studies that reported diagnostic criteria as well as the treatment outcomes achieved in adult patients with CAP were selected for this review.

RESULTS

Three practice guidelines, 5 reviews, and 43 studies on CAP in the elderly were identified in the literature search. Based on those publications, risk factors that predispose the elderly to pneumonia include comorbid conditions, poor functional and nutritional status, consumption of alcohol, and smoking. The clinical presentation of pneumonia in the elderly (>/=65 years of age) may be subtle, lacking the typical acute symptoms (fever, cough, dyspnea, and purulent sputum) observed in younger adults. Pneumonia should be suspected in all elderly patients who have fever, altered mental status, or a sudden decline in functional status, with or without lower respiratory tract symptoms such as cough, purulent sputum, and dyspnea. Treatment of CAP in the elderly should be guided by the latest recommendations of the Infectious Diseases Society of America and the American Thoracic Society (IDSA/ATS), along with consideration of local rates and patterns of antimicrobial resistance, as well as individual patient risk factors for acquiring less common or more resistant pathogens. Recommended empiric antimicrobial regimens generally consist of either a beta-lactam plus a macrolide or a respiratory fluoroquinolone alone. Adherence to the IDSA/ATS guidelines has been found to improve in-hospital mortality (adherence vs nonadherence, 8%; 95% CI, 7%-10% vs 17%; 95% CI, 14%-20%; P< 0.01), length of hospital stay (8 days; interquartile range [IQR], 5-15 vs 10 days; IQR, 6-24 days, respectively; P < 0.01), and time to clinical stability in elderly patients with CAP (percentage of stable patients by day 7, 71%; 95% CI, 68%-74% vs 57%; 95% CI, 53%-61%, respectively; P < 0.01). All elderly patients should be vaccinated against pneumococcal disease and influenza based on recommendations from the Centers for Disease Control and Prevention. Lifestyle modifications and nutritional support are also important elements in the prevention of pneumonia in the elderly.

CONCLUSION

Adherence to established guidelines, along with customization of antimicrobial therapy based on local rates and patterns of resistance and patient-specific risk factors, likely will improve the treatment outcome of elderly patients with CAP.

Clinical and economic burden of pneumococcal disease in older US adults

We developed a model characterizing rates and costs of pneumococcal disease in the US to estimate the expected annual clinical and economic burden of this condition among older adults. Among the 91.5 million US adults aged >or=50 years, 29,500 cases of invasive pneumococcal disease, 502,600 cases of nonbacteremic pneumococcal pneumonia, and 25,400 pneumococcal-related deaths are estimated to occur yearly; annual direct and indirect costs are estimated to total $3.7 billion and $1.8 billion, respectively. Pneumococcal disease remains a substantial burden among older US adults, despite increased coverage with PPV23 and indirect benefits afforded by PCV7 vaccination of young children.

Mixed community-acquired lower respiratory tract infections

Although mixed infections are known to be clinically relevant in conditions such as nosocomial pneumonia and ventilator-related pneumonia, it is increasingly recognized that a substantial number of community-acquired lower respiratory tract infections may also be attributed to more than one pathogenic organism. A better definition of the true incidence of mixed infections in community-acquired lower respiratory tract infections is partly derived from recent advances in available diagnostic methods (eg, molecular biology). Two points still must be determined: whether the presence of a mixed infection is associated with altered outcomes and whether empirical antibiotic selection should be modified to account for potential polymicrobial infections.

Ethanol upregulates glucocorticoid-induced leucine zipper expression and modulates cellular inflammatory responses in lung epithelial cells

Alcohol abuse is associated with immunosuppressive and infectious sequelae. Particularly, alcoholics are more susceptible to pulmonary infections. In this report, gene transcriptional profiles of primary human airway epithelial cells exposed to varying doses of alcohol (0, 50, and 100 mM) were obtained. Comparison of gene transcription levels in 0 mM alcohol treatments with those in 50 mM alcohol treatments resulted in 2 genes being upregulated and 16 genes downregulated by at least 2-fold. Moreover, 0 mM and 100 mM alcohol exposure led to the upregulation of 14 genes and downregulation of 157 genes. Among the upregulated genes, glucocorticoid-induced leucine zipper (GILZ) responded to alcohol in a dose-dependent manner. Moreover, GILZ protein levels also correlated with this transcriptional pattern. Lentiviral expression of GILZ small interfering RNA in human airway epithelial cells diminished the alcohol-induced upregulation, confirming that GILZ is indeed an alcohol-responsive gene. Gene silencing of GILZ in A549 cells resulted in secretion of significantly higher amounts of inflammatory cytokines in response to IL-1beta stimulation. The GILZ-silenced cells were more resistant to alcohol-mediated suppression of cytokine secretion. Further data demonstrated that the glucocorticoid receptor is involved in the regulation of GILZ by alcohol. Because GILZ is a key glucocorticoid-responsive factor mediating the anti-inflammatory and immunosuppressive actions of steroids, we propose that similar signaling pathways may play a role in the anti-inflammatory and immunosuppressive effects of alcohol.