Review

Authors: Vandana Kalwaje Eshwara, Chiranjay Mukhopadhyay, Jordi Rello...

Community-acquired pneumonia (CAP) is the prominent cause of mortality and morbidity with important clinical impact across the globe. India accounts for 23 per cent of global pneumonia burden with case fatality rates between 14 and 30 per cent, and Streptococcus pneumoniae is considered a major bacterial aetiology. Emerging pathogens like Burkholderia pseudomallei is increasingly recognized as an important cause of CAP in Southeast Asian countries. Initial management in the primary care depends on clinical assessment while the hospitalized patients require combinations of clinical scores, chest radiography and various microbiological and biomarker assays. This comprehensive diagnostic approach together with additional sampling and molecular tests in selected high-risk patients should be practiced. Inappropriate therapy in CAP in hospitalized patients lengthens hospital stay and increases cost and mortality. In addition, emergence of multidrug-resistant organisms poses tough challenges in deciding empirical as well as definitive therapy. Developing local evidence on the cause and management should be a priority to improve health outcomes in CAP.

Topics: Adult; Anti-Bacterial Agents; Bacteria; Community-Acquired Infections; Humans; India; Pneumonia; Pneumonia, Bacterial; Streptococcus pneumoniae

PubMed: 32461392
DOI: 10.4103/ijmr.IJMR_1678_19

Review

Authors: Patrick M Meyer Sauteur

Community-acquired pneumonia (CAP) is a common disease in children, and its aetiological and clinical diagnosis are challenging for physicians in both private practice and hospitals. Over the past three decades, conjugate vaccines have successfully reduced the burden of the former main causes of CAP, Streptococcus pneumoniae and Haemophilus influenzae type b. Today, viruses are by far the most commonly detected pathogens in children with CAP.  Conclusion: New insights into the aetiology and treatment of CAP in children in recent years have influenced management and are the focus of this review. In addition to reducing diagnostic uncertainty, there is an urgent need to reduce antibiotic overuse and antimicrobial resistance in children with CAP. What is Known: • Conjugate vaccines against Streptococcus pneumoniae and Haemophilus influenzae type b have shifted the epidemiology of childhood CAP to predominantly viral pathogens and Mycoplasma pneumoniae. • Clinical, laboratory, and radiological criteria cannot reliably distinguish between bacterial and viral aetiology in children with CAP. What is New: • Test results and epidemiological data must be carefully interpreted, as no single diagnostic method applied to non-pulmonary specimens has both high sensitivity and high specificity for determining pneumonia aetiology in childhood CAP. • This review provides a simple and pragmatic management algorithm for children with CAP to aid physicians in providing optimal and safe care and reducing antibiotic prescribing.

Topics: Child; Humans; Pneumonia, Bacterial; Pneumonia; Streptococcus pneumoniae; Bacteria; Anti-Bacterial Agents; Vaccines; Community-Acquired Infections

PubMed: 38112800
DOI: 10.1007/s00431-023-05366-6

Review

Authors: B A Cunha

Pneumonia is one of the commonest infections in elderly patients. The pathogens responsible for pneumonias in the elderly are the same as in younger adults. Because of associated cardiopulmonary disease and/or impaired host defenses, pneumonia in elderly patients is associated with increased mortality and morbidity compared to younger patients. The clinical importance of pneumonias in the elderly relates to age-dependent and pathologic changes in the immune system as well as the lungs. Pneumonias in the elderly may be classified, for clinical purposes, according to their location of acquisition, i.e. community-acquired pneumonias, nursing home-acquired pneumonias, or hospital-acquired pneumonias. The clinical presentation of pneumonias in the elderly may be difficult, due to pre-existing cardiopulmonary disease that mimics pneumonia. This review discusses the diagnostic and therapeutic approaches to elderly patients with pneumonia.

Topics: Aged; Community-Acquired Infections; Cross Infection; Humans; Nursing Homes; Pneumonia

PubMed: 11737082
DOI: 10.1046/j.1198-743x.2001.00328.x

Review

Authors: Dustin K Smith, Daniel P Kuckel, Anthony M Recidoro...

In the United States, pneumonia is the most common cause of hospitalization in children. Even in hospitalized children, community-acquired pneumonia is most likely of viral etiology, with respiratory syncytial virus being the most common pathogen, especially in children younger than two years. Typical presenting signs and symptoms include tachypnea, cough, fever, and anorexia. Findings most strongly associated with an infiltrate on chest radiography in children with clinically suspected pneumonia are grunting, history of fever, retractions, crackles, tachypnea, and the overall clinical impression. Chest radiography should be ordered if the diagnosis is uncertain, if patients have hypoxemia or significant respiratory distress, or if patients fail to show clinical improvement within 48 to 72 hours after initiation of antibiotic therapy. Outpatient management of community-acquired pneumonia is appropriate in patients without respiratory distress who can tolerate oral antibiotics. Amoxicillin is the first-line antibiotic with coverage for Streptococcus pneumoniae for school-aged children, and treatment should not exceed seven days. Patients requiring hospitalization and empiric parenteral therapy should be transitioned to oral antibiotics once they are clinically improving and able to tolerate oral intake. Childhood and maternal immunizations against S. pneumoniae, Haemophilus influenzae type b, Bordetella pertussis, and influenza virus are the key to prevention.

Topics: Community-Acquired Infections; Humans; Pediatrics; Pneumonia; United States

PubMed: 34913645
DOI: No ID Found

Authors: Yan-Ning Liu, Yun-Fa Zhang, Qiang Xu...

BACKGROUND

Severe community-acquired pneumonia (SCAP) is associated with a substantial number of hospitalisations and deaths worldwide. Infection or co-infection patterns, along with their age dependence and clinical effects are poorly understood. We aimed to explore the causal and epidemiological characteristics by age, to better describe patterns of community-acquired pneumonia (CAP) and their association with severe disease.

METHODS

National surveillance of CAP was conducted through a network of hospitals in 30 provinces in China from 2009-20 inclusive. Patients with CAP were included if they had evidence of acute respiratory tract, had evidence of pneumonia by chest radiography, diagnosis of pneumonia within 24 h of hospital admission, and resided in the study catchment area. For the enrolled patients with CAP, nasopharyngeal and oral swabs were taken and tested for eight viral pathogens; and blood, urine, or expectorated sputum was tested for six bacterial pathogens. Clinical outcomes, including SCAP, were investigated with respect to age and patterns of infections or co-infections by performing binary logistic regression and multivariate analysis.

FINDINGS

Between January, 2009, and December, 2020, 18 807 patients with CAP (3771 [20·05%] with SCAP) were enrolled. For both children (aged ≤5 years) and older adults (aged >60 years), a higher overall rate of viral and bacterial infections, as well as viral-bacterial co-infections were seen in patients with SCAP than in patients with non-SCAP. For adults (aged 18-60 years), however, only a higher rate of bacterial-bacterial co-infection was observed. The most frequent pathogens associated with SCAP were respiratory syncytial virus (RSV; 21·30%) and Streptococcus pneumoniae (12·61%) among children, and influenza virus (10·94%) and Pseudomonas aeruginosa (15·37%) among older adults. Positive rates of detection of most of the tested pathogens decreased during 2020 compared with the 2009-19 period, except for RSV, P aeruginosa, and Klebsiella pneumoniae. Multivariate analyses showed SCAP was significantly associated with infection with human adenovirus, human rhinovirus, K pneumoniae, or co-infection of RSV and Haemophilus influenzae or RSV and Staphylococcus aureus in children and adolescents (aged <18 years), and significantly associated with infection with P aeruginosa, K pneumoniae, or S pneumoniae, or co-infection with P aeruginosa and K pneumoniae in adults (aged ≥18 years).

INTERPRETATION

Both prevalence and infection pattern of respiratory pathogens differed between patients with SCAP and patients with non-SCAP in an age-dependent manner. These findings suggest potential advantages to age-related strategies for vaccine schedules, as well as clinical diagnosis, treatment, and therapy.

FUNDING

China Mega-Project on Infectious Disease Prevention and The National Natural Science Funds of China.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Topics: Child; Adolescent; Humans; Adult; Aged; Coinfection; Pneumonia; Streptococcus pneumoniae; Virus Diseases; Respiratory Syncytial Virus, Human; Klebsiella pneumoniae; Community-Acquired Infections

PubMed: 37001538
DOI: 10.1016/S2666-5247(23)00031-9

Review

Authors: J H Reynolds, G McDonald, H Alton...

Pneumonia is an acute inflammation of the lower respiratory tract. Lower respiratory tract infection is a major cause of mortality worldwide. Pneumonia is most common at the extremes of life. Predisposing factors in children include an under-developed immune system together with other factors, such as malnutrition and over-crowding. In adults, tobacco smoking is the single most important preventable risk factor. The commonest infecting organisms in children are respiratory viruses and Streptoccocus pneumoniae. In adults, pneumonia can be broadly classified, on the basis of chest radiographic appearance, into lobar pneumonia, bronchopneumonia and pneumonia producing an interstitial pattern. Lobar pneumonia is most commonly associated with community acquired pneumonia, bronchopneumonia with hospital acquired infection and an interstitial pattern with the so called atypical pneumonias, which can be caused by viruses or organisms such as Mycoplasma pneumoniae. Most cases of pneumonia can be managed with chest radiographs as the only form of imaging, but CT can detect pneumonia not visible on the chest radiograph and may be of value, particularly in the hospital setting. Complications of pneumonia include pleural effusion, empyema and lung abscess. The chest radiograph may initially indicate an effusion but ultrasound is more sensitive, allows characterisation in some cases and can guide catheter placement for drainage. CT can also be used to characterise and estimate the extent of pleural disease. Most lung abscesses respond to medical therapy, with surgery and image guided catheter drainage serving as options for those cases who do not respond.

Topics: Female; Humans; Immunocompromised Host; Lung; Male; Pneumonia; Radiography; Reproducibility of Results; Risk Factors; Streptococcus pneumoniae

PubMed: 21088086
DOI: 10.1259/bjr/31200593

Review

Authors: Lionel A Mandell

Community-acquired pneumonia is still a significant cause of morbidity and mortality and is often misdiagnosed and inappropriately treated. Although it can be caused by a wide variety of micro-organisms, the pneumococcus, atypicals, such as Mycoplasma pneumoniae and Chlamydophila pneumoniae, Staphylococcus aureus and certain Gram-negative rods are the usual pathogens encountered. The site-of-care decision is critical in determining the site and type of care as well as the extent of diagnostic workup. Antimicrobial therapy should be started as soon as possible particularly in those requiring admission to hospital, but typically the physician does not know with any degree of certainty the identity of the etiologic pathogen. A number of national guidelines have been published to help the physician with this choice. The initial drug(s) can be modified if necessary if the pathogen and its antimicrobial susceptibility pattern becomes known. Adjunctive therapy such as pressors and fluid replacement are of value and macrolides appear to help as well, likely secondary to their immunomodulatory effects. Recent data also suggest a role for steroids.

Topics: Anti-Bacterial Agents; Antiviral Agents; Community-Acquired Infections; Humans; Pneumonia

PubMed: 26224210
DOI: 10.1080/00325481.2015.1074030

Review

Authors: Girish B Nair, Michael S Niederman

While the world is grappling with the consequences of a global pandemic related to SARS-CoV-2 causing severe pneumonia, available evidence points to bacterial infection with Streptococcus pneumoniae as the most common cause of severe community acquired pneumonia (SCAP). Rapid diagnostics and molecular testing have improved the identification of co-existent pathogens. However, mortality in patients admitted to ICU remains staggeringly high. The American Thoracic Society and Infectious Diseases Society of America have updated CAP guidelines to help streamline disease management. The common theme is use of timely, appropriate and adequate antibiotic coverage to decrease mortality and avoid drug resistance. Novel antibiotics have been studied for CAP and extend the choice of therapy, particularly for those who are intolerant of, or not responding to standard treatment, including those who harbor drug resistant pathogens. In this review, we focus on the risk factors, microbiology, site of care decisions and treatment of patients with SCAP.

Topics: Community-Acquired Infections; Disease Management; Drug Resistance, Multiple, Bacterial; Guidelines as Topic; Humans; Intensive Care Units; Pneumonia

PubMed: 32805298
DOI: 10.1016/j.pharmthera.2020.107663

Authors: J J Arenas-Jiménez, E García-Garrigós, A Ureña Vacas...

Organizing pneumonia is a nonspecific pathologic pattern of response to lung damage. It can be idiopathic, or it can occur secondary to various medical processes, most commonly infections, connective tissue disease, and pharmacological toxicity. Although there is no strict definition of the pattern of organising pneumonia as in other idiopathic interstitial pneumonias, the characteristic pattern of this disease could be considered to include patchy consolidations and ground-glass opacities in the peribronchial and subpleural areas of both lungs. Moreover, studies of the course of the disease show that these lesions respond to treatment with corticoids, migrate with or without treatment, and tend to recur when treatment is decreased or withdrawn. Other manifestations of organising pneumonia include nodules of different sizes and shapes, solitary masses, nodules with the reverse halo sign, a perilobular pattern, and parenchymal bands.

Topics: Lung; Humans; Lung Diseases; Pneumonia; Tomography, X-Ray Computed; Organizing Pneumonia

PubMed: 36737163
DOI: 10.1016/j.rxeng.2022.08.002

Review

Authors: David M le Roux, Heather J Zar

Pneumonia remains the leading cause of death in children outside the neonatal period, despite advances in prevention and management. Over the last 20 years, there has been a substantial decrease in the incidence of childhood pneumonia and pneumonia-associated mortality. New conjugate vaccines against Haemophilus influenzae type b and Streptococcus pneumoniae have contributed to decreases in radiologic, clinical and complicated pneumonia cases and have reduced hospitalization and mortality. The importance of co-infections with multiple pathogens and the predominance of viral-associated disease are emerging. Better access to effective preventative and management strategies is needed in low- and middle-income countries, while new strategies are needed to address the residual burden of disease once these have been implemented.

Topics: Child; Community-Acquired Infections; Hospitalization; Humans; Incidence; Pneumococcal Vaccines; Pneumonia; Risk Factors

PubMed: 29043417
DOI: 10.1007/s00247-017-3827-8