Changes in bronchial inflammation during acute exacerbations of chronic bronchitis.

There are little data describing noncellular changes in bronchial inflammation during exacerbations of chronic bronchitis. The relationship between sputum colour and airway inflammation at presentation has been assessed during an exacerbation in patients with chronic bronchitis and a primary care diagnosis of chronic obstructive pulmonary disease. Sputum myeloperoxidase, neutrophil elastase, leukotriene B4 (LTB4), interleukin-8 (IL-8), sol:serum albumin ratio and serum C-reactive protein were measured in patients presenting with an exacerbation and mucoid (n = 27) or purulent sputum (n = 42). Mucoid exacerbations were associated with little bronchial or systemic inflammation at presentation, and sputum bacteriology was similar to that obtained in the stable state. Purulent exacerbations were associated with marked bronchial and systemic inflammation (p < 0.025 for all features) and positive sputum cultures (90%). Resolution was related to a significant reduction in LTB4 (p < 0.01), but no change in IL-8, suggesting that LTB4 may be more important in neutrophil recruitment in these mild, purulent exacerbations. In the stable state, IL-8 remained higher in patients who had experienced a purulent exacerbation (2p < 0.02). The presented results indicate that exacerbations of chronic bronchitis, defined by sputum colour, differ in the degree of bronchial and systemic inflammation. Purulent exacerbations are related to bacterial infection, and are associated with increased neutrophilic inflammation and increased leukotriene B4 concentrations.     

Acute exacerbations of chronic bronchitis

Acute exacerbations of chronic bronchitis are one of the major public health challenges. New data suggest that they will remain so for many years. Although the role of bacteria in the initiation and maintenance of bronchial inflammation, both during and between exacerbations, is well recognized, studies of the long-term effects of therapy are few and inadequate, and the nature of the relationship with disease progression is largely unknown. Data are beginning to emerge that firmly link bacterial inflammation and progressive disease with physiological and functional disability. Methods are being developed to provide integrated, uncomplicated and reproducible assessments of health-related quality of life. These may prove fundamental to the proper investigation of new treatment modalities. Among the newer antibacterial agents, fluoroquinolones have received most investigative attention, regrettably usually without providing clinical confirmation of their obvious superiority in vitro and of their pharmacokinetic and related pharmacodynamic properties. New trial designs need to address an integrated outcome analysis, with the assessment of long-term benefit and pharmaco-economic monitoring. More antibacterial agents are available at the millennium than ever before. After 50 years, it would be preferable if we knew a little more about their role in this complex disease.     

Epidemiology of chronic bronchitis and acute infective exacerbations of chronic bronchitis

Acute exacerbations of chronic bronchitis (AECBs) are one of the major causes of morbidity and mortality in the United States, resulting in significant cost to the health care system. Epidemiological information on chronic bronchitis is abundant and has been collected in most industrialized countries. The epidemiology of AECB, however, is less forthcoming. The causes of AECB are multifactorial and include environmental pollutants, allergic responses, and viral and bacterial infections. The role of bacterial infection in AECB is controversial but is believed to account for half of AECB. Because the medical and economic implications of treatment failure in these patients are substantial, an aggressive approach to stratify and treat these patients is necessary. Epidemiological data on chronic bronchitis and acute infective exacerbations of chronic bronchitis will allow us to more precisely define the role of bacterial infection in AECB, and this information may help guide antimicrobial therapy.     

哮喘、慢性支气管炎急性发作及肺炎病例支原体感染的调查

肺炎支原体(Mycoplasma pneumoniae,MP)是呼吸道感染的常见病原之一,而支气管哮喘、慢性支气管炎和社区获得性肺炎是呼吸系的常见病、多发病.它们的病原学一直是广大呼吸科医生研究的热点之一,但尚未见到MP在上述疾病中感染情况比较的研究.本文对此进行了研究、分析,现将结果报告如下.     

Antibiotic therapy of exacerbations of chronic bronchitis

The role of antibiotics in acute exacerbations of chronic bronchitis (AECB) remains controversial because patients commonly harbor the same bacteria in their sputum at times of stability and at times of acute illness. However, prospective randomized controlled trials do show a benefit for the use of antibiotics, compared with placebo, in AECB, particularly if patients have at least 2 of the following 3 symptoms: increased dyspnea, increased sputum volume, increased sputum purulence. In this setting, antibiotics have value, leading to a more rapid resolution of symptoms and a more rapid return of peak flow rate, compared with placebo. In addition, antibiotics may prevent some patients from developing secondary pneumonia and may prolong the time between exacerbations. When antibiotics are used, a variety of factors must be considered in choosing an agent. These include the likelihood of antibiotic-resistant bacteria, a factor that relates to defining subsets of patients. Patients can fall into 1 of 3 categories, each with a different suggested therapy. These categories include simple AECB, complicated AECB, and AECB at risk for infection with P. aeruginosa. In addition, an antibiotic should be chosen with pharmacokinetics and pharmacodynamic behavior in mind. In the future, research will need to confirm that careful selection of specific agents for specific patients can lead to improved patient outcomes, but already some preliminary data are supporting this concept.     

Interactions between viruses and bacteria in patients with chronic bronchitis.

The possibility that viral infections of the respiratory tract might predispose to bacterial colonization or infection was studied in 120 patients with chronic obstructive pulmonary disease and 30 control subjects; these individuals were observed for seven years. The ratio of the number of observed to the number of expected associations between viruses and bacteria was 2.43 (P = 0.037) for the pair influenza virus and Streptococcus pneumoniae and was 2.06 (P = 0.056) for influenza virus and Haemophilus influenzae. Consistently positive, but not significant, associations were detected between rhinovirus and herpes simplex virus infections and isolations of S. pneumoniae and H. influenzae. In contrast, isolations of the nonpathogenic Haemophilus parainfluenzae could not be related to prior viral infections. Significant rises in titer of antibody to H. influenzae were detected on 76 occasions, and 20 (26%) of these antibody rises were associated with viral or mycoplasmal infections during the preceding 120 days. The expected number of such associations was 8.34 (ratio of number observed to number expected, 2.40; P = 0.08). These results suggest that viral infections of the respiratory tract in patients with chronic obstructive pulmonary disease are associated with increased colonization by potentially pathogenic bacteria and may also predispose to infections with H. influenzae.     

Cost-effective therapy for acute exacerbations of chronic bronchitis

Pharmacoeconomic analysis involves the measurement of a ratio determining the extra costs required to achieve an additional unit of clinical benefit. Various techniques including modeling studies, retrospective analysis of databases, "piggy-back" economic analysis of prospective randomized clinical trials, and prospective randomized pharmacoeconomic trials have been developed to aid in economic and health decisions. In acute exacerbations of chronic obstructive pulmonary disease, it is possible to identify a group of patients that are at high risk of treatment failure from routine antimicrobial therapy, hospitalization, respiratory failure, and death. The cost of therapy for this relatively small group of patients is extraordinarily high. Data from a variety of approaches have suggested that aggressive antimicrobial therapy may lead to improved outcomes in these patients.The corollary is that aggressive therapy directed toward patients with either acute bronchitis (mainly a viral infection) or exacerbations of trivial chronic obstructive lung disease leads to emergence of resistance and increased costs.     

哮喘性支气管炎患儿肺炎支原体抗体检测及分析

为更好地提高患儿哮喘性支气管炎的治疗效果 ,探讨该类患儿的感染病原 ,特对本院患儿及正常儿童的肺炎支原体抗体 ( Mycoplasma pneumomiaeantibody-Ig M)进行了检测 ,现将结果报告如下。1　资料和方法1 .1　资料来源观察组 :64例患儿均符合王慕狄主编的儿科学中哮喘性支气管炎的诊断标准。为本院儿科 2 0 0 0年 9月至2 0 0 3年 9月住院患儿 ,均在近期 2周内感染。男 3 6例 ,女2 8例 ;年龄 6个月～ 1岁 1 2例 ,1～ 3岁 1 8例 ,>3岁 3 4例。对照组 :正常儿童 47例 ,男 2 2例 ,女 2 5例 ;年龄 6个月～ 1岁 1 0例 ,1～ 3岁 1 6例 ,>3岁 2 1例…     

Antibiotic therapy in acute exacerbations of chronic bronchitis

Chronic obstructive pulmonary disease (COPD) comprises a spectrum of conditions including chronic bronchitis, emphysema, asthma, and bronchiectasis. It has a prevalence in the United States of 5.1% to 5.4% in the middle-aged to elderly population, with a lower rate in nonsmoking individuals. Moreover, COPD is complicated by frequent and recurring acute exacerbations of chronic bronchitis (AECB). Overall, COPD represents the fourth leading cause of mortality in the United States and is the second leading cause of work disability. This condition is also associated with high morbidity and health care expenditures. Despite the controversy over the need to prescribe antibiotics for patients with AECB, high-risk patients have been identified who will benefit from this therapy.These include, patients with a history of repeated infections (>4 per year), comorbid illnesses (such as diabetes, asthma, coronary heart disease), or marked airway obstruction. Furthermore, a bacterial cause is shown in approximately 50% of AECB episodes, and primarily includes Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. Additionally, resistance among community-acquired respiratory pathogens in the United States has risen dramatically, with beta-lactamase production evident in 40% of H. influenzae and greater than 95% of M. catarrhalis isolates, and with approximately 10% of pneumococci highly resistant to penicillin and simultaneously resistant to macrolide antibiotics. The criteria used to make choices for antibiotic use in patients with AECB should include knowledge of the frequencies of pathogen resistance and patients' clinical characteristics. An effective antibiotic, however, must be able to rapidly resolve the acute infection with the least patient morbidity and need for hospitalization. Although there remains controversy as to when to initiate antibiotic therapy in patients with AECB, several guidelines have been published.     

Airway inflammation and etiology of acute exacerbations of chronic bronchitis

STUDY OBJECTIVES: The etiologic role of bacterial pathogens isolated from sputum culture in 40 to 50% of acute exacerbations of chronic bronchitis (AECB) is controversial. If bacterial pathogens cause these AECB, they should be associated with greater neutrophilic airway inflammation than pathogen-negative exacerbations. DESIGN: This hypothesis was tested by comparing levels of interleukin (IL)-8, tumor necrosis factor (TNF)-alpha, and neutrophil elastase (NE) in 81 sputum samples obtained from 45 patients with AECB. Four groups were compared. In the first three groups, nontypable Haemophilus influenzae (n = 20), Haemophilus parainfluenzae (n = 27), and Moraxella catarrhalis (n = 14) were isolated as sole pathogens, respectively. In the fourth group, only normal flora was isolated (n = 20). Paired samples, obtained from individual patients at different times, that differed in their culture results were also compared. SETTING: An outpatient research clinic at a Veterans Affairs Medical Center. PATIENTS: These patients were participating in a prospective, longitudinal study of the dynamics of bacterial infection in chronic bronchitis, for which they were seen in the study clinic on a monthly basis as well as when they were experiencing symptoms suggestive of AECB. INTERVENTIONS: None. Measurements and results: H influenzae exacerbations were associated with significantly higher sputum IL-8, TNF-alpha, and NE. M catarrhalis exacerbations demonstrated significantly higher sputum TNF-alpha and NE when compared to pathogen-negative exacerbations. H parainfluenzae-associated exacerbations had an inflammatory profile similar to pathogen-negative exacerbations. Sputum elastase level distinguished bacterial from nonbacterial AECB and correlated with clinical severity of the AECB. CONCLUSIONS: Increased airway inflammation associated with isolation of H influenzae and M catarrhalis supports an etiologic role of these pathogens in AECB.     

Pharmacoeconomic evaluation of acute exacerbations of chronic bronchitis and COPD

BACKGROUND: Although exacerbations are the main cause of medical visits and hospitalizations of patients with chronic bronchitis and COPD, little information is available on the costs of their management. OBJECTIVE: This study attempted to determine the total direct costs derived from the management of exacerbations of chronic bronchitis and COPD in an ambulatory setting. METHOD: A total of 2,414 patients with exacerbated chronic bronchitis and COPD were recruited from 268 general practices located throughout Spain. Patients were followed up for 1 month. RESULTS: A total of 507 patients (21%) relapsed; of these, 161 patients (31.7%) required attention in emergency departments and 84 patients (16.5%) were admitted to the hospital. The total direct mean cost of all exacerbations was $159; patients who were hospitalized generated 58% of the total cost. Cost per failure was $477.50, and failures were responsible for an added mean cost of $100.30/exacerbation. Exacerbations of the 1,130 patients with COPD had a mean cost of $141. Sensitivity analysis showed that a 50% reduction in the failure rate (from 21 to 10.5%) would result in a total cost of exacerbation of $107 (33% reduction). CONCLUSION: Exacerbations of chronic bronchitis and COPD are costly, but the greatest part of costs derives from therapeutic failures, particularly those that end in hospitalization.     

The role of antimicrobial therapy in acute exacerbations of chronic bronchitis.

Acute exacerbations of chronic bronchitis (AECB) result in increased morbidity and mortality. The role of bacteria in AECB, the importance of antimicrobial therapy, and the choice of antimicrobial agents have been debated for decades. Fortunately, within the past few years, a number of studies and one consensus statement have been reported that have increased the understanding of the role of bacteria in AECB and suggest approaches in selecting antimicrobial therapy. This article will review these studies and present an empiric approach in treating AECB based upon the patient's presenting findings, related risk factors, and potential antimicrobial resistance patterns that may be encountered.