Relationship of sputum color to nature and outpatient management of acute exacerbations of COPD

COPD exacerbations: the importance of a standard definition

Efforts to assess the efficacy of new therapies in the treatment of acute exacerbations of chronic obstructive pulmonary disease (COPD) have been hampered by the lack of a widely agreed and consistently used definition. A variety of definitions have been used in clinical studies, based on changes in patient symptoms or the requirement for antibiotic therapy, oral steroids or hospitalisation. To date, none of these definitions have been assessed in detail for their reliability, responsiveness and validity determined. Considerable heterogeneity in the aetiology and manifestation of COPD exacerbations makes identification and quantification of defining symptoms extremely difficult. New approaches are therefore being sought with a view to identifying a serum or tissue marker that can be used as a valuable diagnostic tool. Improvements in data recording will also contribute to the accuracy of data retrieval and assessment. If we are to progress to a level of sophistication seen in the diagnosis and management of other diseases, it is evident that considerable research efforts will be required to improve our understanding of COPD exacerbations and develop a standard definition for these events, thereby facilitating the assessment of therapeutic approaches.

Acute bronchitis: state of the art diagnosis and therapy

In managing acute bronchitis, pneumonia or an exacerbation of underlying chronic bronchitis should be excluded. Simple bronchitis is best treated symptomatically while an exacerbation of chronic bronchitis can be treated with antibiotics. Broad spectrum antibiotics are appropriate in selected patients.

Chronic obstructive pulmonary disease in geriatric critical care

COPD is a progressive disorder that is punctuated in its later stages with acute exacerbations that present a risk for respiratory failure. COPD has a disproportionate impact on older patients. In the ICU, therapy is directed toward unloading fatigued respiratory muscles, treating airway infection, and prescribing bronchodilatory drugs. Most patients survive hospitalization in the ICU for an episode of respiratory failure. The severity of the underlying lung disease, however, underlies the poor outcomes of patients in terms of postdischarge survival and quality of life.

Relationship between chronic nasal and respiratory symptoms in patients with COPD

The relationship between the upper and lower airways in chronic obstructive pulmonary disease (COPD) is unknown. We examined the prevalence of chronic nasal symptoms and the correlation with lower respiratory symptoms and parameters of severity of COPD such as exacerbation frequency and spirometry. 61 COPD patients from the East London COPD cohort were studied. [Mean (SD) age 70 (6.96) years, FEV1 0.98 (0.38) l, FVC 2.45 (0.72) l, FEV1%Pred 37.0 (12.3), and 47.6 (31.8) smoking pack years, 14 current smokers, 36 males]. COPD patients had a high prevalence of nasal symptoms (75%), more than half reporting nasal discharge (52.5%) and sneezing (45.9%). Associations were found between nasal score and daily sputum production (P = 0.005) and post-nasal drip and sputum production (P = 0.046) with a trend to increased nasal symptoms in frequent exacerbators compared to infrequent exacerbators. No significant relationship was found between nasal symptoms and FEV1 or any other lower respiratory airway symptom. Associations between nasal and respiratory symptoms were found suggesting that there is a relationship between the upper and lower airway in COPD.

Resolution of bronchial inflammation is related to bacterial eradication following treatment of exacerbations of chronic bronchitis

BACKGROUND

Recent studies of the role of bacteria in chronic bronchitis have shown that bacterial colonisation is associated with enhanced inflammation and that purulent acute exacerbations of chronic bronchitis (AECB) are associated with bacteria and characterised by increased inflammation. Changes in bronchial inflammation in response to the success or failure of bacterial eradication following AECB were therefore studied.

METHODS

Bacterial quantitative culture and sputum markers of inflammation (myeloperoxidase (MPO), neutrophil elastase, leukotriene B4 (LTB4), sol:serum albumin ratio, and secretory leukoprotease inhibitor) were measured in patients presenting with culture positive purulent AECB and repeated 10 days and 2 months later. 41 patients provided sputum sufficient for both bacteriology and assessment of inflammation at baseline and day 10, and 46 provided sufficient sample for bacteriology, 40 of which could also be analysed for inflammation at 2 months (when clinically stable).

RESULTS

At day 10, 17 of the 41 patient samples had a positive bacterial culture. In the stable state, 18 of the 46 samples had a positive culture, but with a significantly lower bacterial load than at presentation. Although there was no difference between the groups at presentation, the concentration of MPO was lower (p<0.05) in those in whom bacteria were eradicated by day 10 than in those with persisting bacteria. The LTB4 concentration was similarly lower (p<0.001) in those in whom bacteria were eradicated than in those with persistent bacteria. In the stable clinical state the concentrations of both MPO and LTB4 were lower in those in whom bacteria were eradicated than in patients with persisting bacteria.

CONCLUSION

Resolution of bronchial inflammation following AECB is related to bacterial eradication. Those in whom bacteria continue to be cultured in their sputum have partial resolution of inflammation which may reflect continued stimulation by the reduced bacterial load.

Emergency department management of acute exacerbations of chronic obstructive pulmonary disease in the elderly: the Multicenter Airway Research Collaboration

OBJECTIVES

To determine adherence of emergency department (ED) management of acute exacerbation of chronic obstructive pulmonary disease (COPD) to current treatment guidelines.

DESIGN

A prospective cohort study, as part of the Multicenter Airway Research Collaboration.

SETTING

The study was performed at 29 EDs in 15 U.S. states and three Canadian provinces.

PARTICIPANTS

ED patients, aged 55 and older, who presented with COPD exacerbation and underwent a structured interview in the ED and another by telephone 2 weeks later.

MEASUREMENTS

Adherence of ED management of COPD exacerbation to that recommended in current treatment guidelines.

RESULTS

The cohort consisted of 397 subjects, of whom 224 (56%) reported only COPD and 173 (44%) reported asthma and COPD. The average age was 70. Most (80%) patients had used rescue medications in the 6 hours before seeking emergency care. Only 31% were evaluated using spirometry and 48% using arterial blood gas measurement. ED treatment included inhaled short-acting beta-agonists for 91% of patients, inhaled anticholinergics for 77%, methylxanthines for 0.3%, systemic corticosteroids for 62%, and antibiotics for 28%. More than half the patients required hospitalization. At 2-week follow-up, 43% of patients reported a relapse event or ongoing exacerbation. Overall, adherence to national and international guidelines was low.

CONCLUSION

Important differences exist between guideline recommendations and actual ED management of COPD exacerbations in older adults. Outcomes after ED treatment are poor and may be related to these shortcomings in quality of care. Better adherence to guideline recommendations when caring for elderly patients with COPD exacerbations may lead to improved clinical outcomes and better resource usage.

Treatment of acute exacerbations of COPD

Chronic obstructive pulmonary disease (COPD), the fourth leading cause of death in the United States, is increasing worldwide and is projected to be the third leading cause of death in the United States by the year 2020 (1). It affects nearly 16 million Americans, and more than $18 billion is spent annually on medications, physician visits, and hospitalizations. COPD is characterized by chronic airflow obstruction with episodic acute exacerbations, which result in increased morbidity and mortality. Patients hospitalized with exacerbations have an overall mortality rate of 3% to 4%, and up to 24% of patients requiring care in the intensive care unit die (2). Since forced expiratory volume in 1 second correlates closely with life expectancy and exacerbation rate, early diagnosis (through spirometric testing) and prevention may reduce acute exacerbations and health care costs.

Ambulant erworbene und nosokomiale Pneumonie

Mortality of pneumonia is low in the outside setting (1%) but rises up to 20% in hospital admitted patients. Early diagnosis and standardized therapy improve patient's prognosis. For community acquired pneumonia age, comorbidity and the setting of therapy (outside department, normal ward or intensive care unit) are the most important variables to choose an adequate antibiotic treatment. For nosocomial pneumonia risk stratification is according to severity of illness, length of hospital stay and antibiotic pretreatment. In the outpatient setting a 7-day monotherapy is mostly successful. In severe illness the combination of a betalactam antibiotic with a new fluorchinolon seems to be superior to an aminoglycosid therapy. Antibiotic resistance due to mistakes in antibiotic therapy is an increasing problem in the intensive care unit. Therefore, pneumonia preventive measures like influenza and pneumococcal vaccination become more important. Standardized hygienical procedures help to reduce nosocomial, mainly ventilator associated pneumonia.

Chronic obstructive pulmonary disease: role of bacteria and guide to antibacterial selection in the older patient

Chronic obstructive pulmonary disease (COPD) is a common problem in the elderly. The disease is characterised by intermittent worsening of symptoms and these episodes are called acute exacerbations. The best estimate, based on several lines of evidence, is that approximately half of all exacerbations are caused by bacteria. These lines of evidence include studies of lower respiratory tract bacteriology during exacerbations, correlation of airways' inflammation with results of sputum cultures during exacerbations, analysis of immune responses to bacterial pathogens, and the observation in randomised, prospective, placebo-controlled trials that antibacterial therapy is of benefit. The most important bacterial causes of exacerbations of COPD are nontypeable Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae and Chlamydia pneumoniae. In approaching the elderly patient with an exacerbation, it is useful to consider the severity of the exacerbation based on three cardinal symptoms: increased sputum volume, increased sputum purulence and increased dyspnoea compared with baseline. Patients experiencing moderate (two symptoms) or severe (all three symptoms) exacerbations benefit from antibacterial therapy. Consideration of underlying host factors allows for a rational choice of antibacterial agent. Patients are considered to have 'simple COPD' or 'complicated COPD' based on: (i) the severity of underlying lung disease; (ii) the frequency of exacerbations; and (iii) the presence of comorbid conditions. It is proposed that patients with simple COPD are treated with doxycycline, a newer macrolide, or an extended-spectrum oral cephalosporin; and patients with complicated COPD are treated with amoxicillin/clavulanate or a fluoroquinolone. The major goals of antibacterial therapy for exacerbations of COPD are acceleration of symptom resolution and prevention of the complications of exacerbation.

Acute exacerbations of chronic obstructive pulmonary disease

This article discusses the definition, pathophysiology, cause, clinical presentation, laboratory work-up, and treatment of chronic obstructive pulmonary disease (COPD) exacerbation. The focus is on the presentation of acute exacerbations of COPD in the emergency department and the available evidence for testing and treatment.

Airway bacterial load and FEV1 decline in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by an accelerated decline in lung function and progressive airway inflammation. Bacteria have been isolated from the lower airway of stable COPD patients, and airway inflammation has been related to bacterial load and type. The relationship between bacterial colonization, airway inflammation, and lung function decline remains uncertain. We studied 30 patients with COPD, mean (SD) FEV1 0.947 (0.329), 34.8% (13.6%) predicted, for 12 months. Sputum collected at recruitment and the end of the study was analyzed for cytokines and for quantitative bacteriology. The decline in FEV1 was 57.6 (137.6) ml year-1. Bacterial growth was identified in all subjects, with an initial count of 107.47(0.91) cfu ml-1 rising to 107.93(0.81) cfu ml-1 at the end of the study (p = 0.019). FEV1 decline was related to this increase in airway bacterial load (r = 0.59, p = 0.001). FEV1 decline was greater in subjects who exhibited a change in the colonizing bacterial type compared with those with persistence of a single bacterial species over the study period (p = 0.017). Higher sputum interleukin (IL-8) was associated with greater declines in FEV1 (p = 0.03). Rising airway bacterial load and species changes are associated with greater airway inflammation and accelerated decline in FEV1. Bacterial colonization in COPD is an important factor in disease progression.

Increased leukotriene B4 and 8-isoprostane in exhaled breath condensate of patients with exacerbations of COPD

BACKGROUND

Exacerbations are an important feature of chronic obstructive pulmonary disease (COPD), accounting for a large proportion of health care costs. They are associated with increased airway inflammation and oxidative stress.

METHODS

Concentrations of leukotriene B4 (LTB4), a marker of inflammation, and 8-isoprostane, a marker of oxidative stress, were measured in the exhaled breath condensate of 21 patients (11 M) with COPD during an exacerbation and 2 weeks after treatment with antibiotics. In 12 patients who had no further exacerbations these markers were also measured after 2 months.

RESULTS

LTB4 concentrations were raised during the COPD exacerbation (mean (SE) 15.8 (1.1) pg/ml and fell after treatment with antibiotics to 9.9 (0.9) pg/ml (p<0.0001). In 12 patients the level of LTB4 fell further from 10.6 (1.1) pg/ml to 8.5 (0.8) pg/ml (p<0.005) after 2 months. In 12 normal age matched subjects the LTB4 levels were 7.7 (0.5) pg/ml. Concentrations of 8-isoprostane were also increased during the exacerbation (13.0 (0.9) pg/ml) and fell after antibiotic treatment to 9.0 (0.6) pg/ml (p<0.0001). In 12 patients there was a further fall from 9.3 (0.7) pg/ml to 6.0 (0.7) pg/ml (p<0.001) after 2 months compared with normal subjects (6.2 (0.4) pg/ml).

CONCLUSIONS

Non-invasive markers of inflammation and oxidative stress are increased during an infective exacerbation of COPD and only slowly recover after treatment with antibiotics.

Association between glycemic state and lung function: the Framingham Heart Study

Diabetes mellitus has been inconsistently associated with a reduced level of pulmonary function. To elucidate this association further, we analyzed the relationship of diabetes and of fasting blood glucose to the level of pulmonary function assessed by spirometry in the 3,254 members of the Framingham Offspring Cohort. Diabetes was defined as a fasting blood glucose of 126 mg/dl or more or pharmacologic treatment. Subjects were classified as current, former, or never smokers based on questionnaire responses. Predicted pulmonary function was determined from the coefficients of a regression of pulmonary function on age, sex, and body habitus in the 1,110 never smokers. Both the diagnosis of diabetes and a higher level of fasting blood glucose were associated with lower than predicted levels of pulmonary function. The adverse effect of diabetes and glycemic level on pulmonary function was stronger among ever smokers than never smokers, suggesting an interaction between the level of fasting glycemia and tobacco smoking.

Evidence-based approach to acute exacerbations of COPD

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States, and it accounts for approximately 500,000 hospitalizations for exacerbations each year. New definitions of acute COPD exacerbation have been suggested, but the one used by Anthonisen et al. is still widely accepted. It requires the presence of one or more of the following findings: increase in sputum purulence, increase in sputum volume, and worsening of dyspnea. Patients with COPD typically present with acute decompensation of their disease one to three times a year, and 3% to 16% of these will require hospital admission. Hospital mortality of these admissions ranges from 3% to 10% in severe COPD patients, and it is much higher for patients requiring ICU admission. The etiology of the exacerbations is mainly infectious (up to 80%). Other conditions such as heart failure, pulmonary embolism, nonpulmonary infections, and pneumothorax can mimic an acute exacerbation or possibly act as "triggers." Baseline chest radiography and arterial blood gas analysis during an exacerbation are recommended. Oxygen administration through a venturi mask seems to be appropriate and safe, and the oxygen saturation should be kept just above 90%. Either a short acting beta 2-agonist or an anticholinergic is the preferred bronchodilator agent. The choice between the two depends largely on potential undesirable side effects and the patient's coexistent conditions. Adding a second bronchodilator to the first one does not seem to offer much benefit. The evidence suggests similar benefit of MDIs when compared with nebulized treatment for bronchodilator delivery. If MDIs are to be used, spacer devices are recommended. Steroids do improve several outcomes during an acute COPD exacerbation, and a 10- to 14-day course seems appropriate. Antibiotic use has been shown to be beneficial, especially for patients with severe exacerbation. Changes in bacteria strains have been documented during exacerbations, and newer generations of antibiotics might offer a better response rate. There is no role for mucolytic agents or chest physiotherapy in the acute exacerbation setting. Noninvasive positive pressure ventilation might benefit a group of patients with rapid decline in respiratory function and gas exchange. It has the potential to decrease the need for intubation and invasive mechanical ventilation and possibly decrease in-hospital mortality.

A comparison of 5-day courses of dirithromycin and azithromycin in the treatment of acute exacerbations of chronic obstructive pulmonary disease

BACKGROUND

Short-term use of antibiotics has become a common component of the management of acute exacerbations of chronic bronchitis (AECB), particularly in complex cases with productive cough or purulent phlegm. The macrolide antibiotics, particularly second-generation agents such as dirithromycin and azithromycin, are among the antibiotic classes frequently recommended and used to treat upper and lower respiratory infections, including AECB.

OBJECTIVE

This study compared the clinical efficacy and tolerability of 5-day courses of dirithromycin and azithromycin given once daily for the treatment of acute exacerbations of chronic obstructive pulmonary disease (COPD).

METHODS

This randomized, investigator-blinded, parallel-group clinical trial was conducted at 5 centers in the United States. Eligible patients were adult (age >35 years) smokers or ex-smokers (smoking history of at least 10 pack-years) with chronic bronchitis and an acute exacerbation, defined by the occurrence of increased dyspnea and/or productive cough and feverishness within 48 hours of enrollment. Before randomization, an attempt was made to obtain a sputum specimen from each patient for Gram's staining and culture. Patients were randomized to receive dirithromycin 500 mg QD for 5 days or azithromycin 500 mg QD on day 1 and 250 mg QD on days 2 to 5. Clinical efficacy was assessed separately by patients and physicians at early (days 7-10) and late (days 25-35) posttreatment visits.

RESULTS

Eighty-six patients (48 women, 38 men; mean age, 55 years) with a mean smoking history of 31 pack-years were included in the intent-to-treat analysis. Forty-six (54%) patients were randomized to dirithromycin and 40 (47%) patients to azithromycin. Clinical efficacy was reported in a high proportion of patients in both treatment groups, both at the early posttreatment visit (84.8% dirithromycin, 75.7% azithromycin; difference dirithromycin - azithromycin, 9.1%; 95% CI, -8.2 to 26.4) and the late posttreatment visit (95.5% and 86.5%, respectively; difference dirithromycin - azithromycin, 9.0%; 95% CI, -3.7 to 21.6). A similar proportion of patients required a second course of antibiotics over the study period (20.5% dirithromycin, 27.0% azithromycin; difference dirithromycin - azithromycin, -6.6%; 95% CI, -25.2 to 12.1). Only 42 (48.8%) patients were able to produce a sputum sample before receiving study treatment, and of these, only 20 (47.6%) demonstrated a preponderance of neutrophils on Gram's staining. Both treatments were well tolerated.

CONCLUSIONS

The results of this study suggest comparable clinical efficacy between 5-day courses of once-daily dirithromycin and azithromycin in acute exacerbations of COPD. There were insufficient data to permit meaningful comparison of the bacteriologic efficacy of these macrolide antibiotics.

Descompensaciones respiratorias en la enfermedad pulmonar obstructiva crónica

La descompensación en la enfermedad pulmonar obstructiva crónica (EPOC) se define como el agravamiento, en general rápido y reversible, de la situación respiratoria en un paciente con EPOC. Estos trastornos son secundarios a trastornos sobreañadidos que requieren un tratamiento específico (neumopatías infecciosas, embolias pulmonares, neumotórax, insuficiencia cardíaca izquierda, errores terapéuticos, etc.) o a exacerbaciones de los fenómenos inflamatorios bronquiales y de los síntomas crónicos (broncorrea, tos, disnea). Su gravedad es variable y oscila entre las formas bien toleradas que pueden tratarse de manera ambulatoria con un coste escaso y las dificultades respiratorias agudas que precisan reanimación inmediata. La utilización razonada de antibióticos, broncodilatadores en dosis altas, corticoides, oxígeno y ventilación asistida (casi siempre «no invasiva») ha mejorado su pronóstico, que sigue siendo mediocre cuando la descompensación se superpone a una EPOC evolucionada.

Chronic obstructive pulmonary disease . 6: The aetiology of exacerbations of chronic obstructive pulmonary disease

Exacerbations of COPD are thought to be caused by interactions between host factors, bacteria, viruses, and changes in air quality to produce increased inflammation in the lower airway. The evidence for this and the potential mechanisms by which they result in the characteristic symptoms of exacerbations is reviewed. A better understanding of the causes and processes is needed for the appropriate use of existing treatments and the development of new ones. Future studies need to define populations clearly, stratify for known confounding factors, and should aim to identify clinical correlates so that clinical practice can be modified appropriately.

Use of antibiotics in patients admitted to the hospital due to acute exacerbation of chronic obstructive pulmonary disease (COPD)

BACKGROUND: The purpose of this study was to assess to what extent symptoms and signs of bacterial infection are present and evaluated in patients admitted to the hospital for exacerbation of chronic obstructive pulmonary disease (COPD) in relation to initiation of antibiotic treatment. METHODS: All adult patients (>18 years of age) discharged from a department of internal medicine in Copenhagen in 1997 with a diagnosis of exacerbation of COPD were included in our study and their reports were retrospectively reviewed. Gender, age, number of admissions and length of hospital stay, use of antibiotics and steroids prior to admission, temperature, white blood cell (WBC) count, results of lung auscultation and X-ray examination of the thorax at admittance, and growth of sputum culture and antibiotic treatment in the hospital were all registered. RESULTS: A total of 400 admissions took place. In 104 of them, chest X-ray was compatible with pneumonia, and 99 cases were treated with antibiotics. In 44% of the remaining 296 cases, antibiotics were given. It was found that 25-45% of the patients with very little evidence of infection-i.e. the absence of, or only the presence of, one of the following indicators of infection: fever (temperature>37.5 degrees C), a raised WBC count (>9 billion/l), or crepitation at lung auscultation-were given antibiotics. In cases presenting with two or three of these indicators, 50-75% were given antibiotics. In 85% of the cases, penicillin or a macrolide was the initial antibiotic of choice. The median hospital stay was 6 days for the entire group of patients. CONCLUSION: These data suggest that, in patients with acute exacerbation of COPD, a relatively high number of patients with only weak symptoms or signs of bacterial infection are treated with antibiotics.

Relationship between bacterial colonisation and the frequency, character, and severity of COPD exacerbations

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) are prone to frequent exacerbations which are a significant cause of morbidity and mortality. Stable COPD patients often have lower airway bacterial colonisation which may be an important stimulus to airway inflammation and thereby modulate exacerbation frequency.

METHODS

Twenty nine patients with COPD (21 men, 16 current smokers) of mean (SD) age 65.9 (7.84) years, forced expiratory volume in 1 second (FEV(1)) 1.06 (0.41) l, FEV(1) % predicted 38.7 (15.2)%, FEV(1)/FVC 43.7 (14.1)%, inhaled steroid dosage 1.20 (0.66) mg/day completed daily diary cards for symptoms and peak flow over 18 months. Exacerbation frequency rates were determined from diary card data. Induced sputum was obtained from patients in the stable state, quantitative bacterial culture was performed, and cytokine levels were measured.

RESULTS

Fifteen of the 29 patients (51.7%) were colonised by a possible pathogen: Haemophilus influenzae (53.3%), Streptococcus pneumoniae (33.3%), Haemophilus parainfluenzae (20%), Branhamella catarrhalis (20%), Pseudomonas aeruginosa (20%). The presence of lower airway bacterial colonisation in the stable state was related to exacerbation frequency (p=0.023). Patients colonised by H influenzae in the stable state reported more symptoms and increased sputum purulence at exacerbation than those not colonised. The median (IQR) symptom count at exacerbation in those colonised by H influenzae was 2.00 (2.00-2.65) compared with 2.00 (1.00-2.00) in those not colonised (p=0.03). The occurrence of increased sputum purulence at exacerbation per patient was 0.92 (0.56-1.00) in those colonised with H influenzae and 0.33 (0.00-0.60) in those not colonised (p=0.02). Sputum interleukin (IL)-8 levels correlated with the total bacterial count (rho=0.459, p=0.02).

CONCLUSION

Lower airway bacterial colonisation in the stable state modulates the character and frequency of COPD exacerbations.

Treatment of COPD exacerbations. Pharmacologic options and modification of risk factors

Exacerbations of COPD are a major source of morbidity and mortality, resulting in tremendous increases in healthcare costs. Spirometric testing of at-risk persons can help identify patients early in the disease course who may benefit from early intervention to slow the disease process. Avoidance of irritants, smoking cessation, and use of pharmacologic agents aimed at decreasing airflow obstruction are strategies for reducing the frequency and severity of exacerbations. Patients should be educated about modifiable risk factors, such as cigarette smoking, environmental exposures, improper inhaler technique, influenza and pneumonia vaccination, pulmonary rehabilitation, and use of supplemental oxygen. Early, aggressive interventions are necessary to improve quality of life, decrease hospital admissions, improve morbidity and mortality, and reduce overall healthcare costs.

Exacerbations: etiology and pathophysiologic mechanisms

Some patients with COPD are prone to frequent exacerbations, which are an important determinant of health status. Such patients have elevated airway cytokine levels, suggesting the presence of increased inflammation that may increase their susceptibility to exacerbation. The inflammatory response during a COPD exacerbation is variable, but increases in interleukin-6 levels during the exacerbation are related to the presence of a common cold. Rhinovirus infection is the most important etiologic factor in COPD exacerbations and is an important target for preventive therapy. The reduction of COPD exacerbations will have an important impact on the considerable morbidity and mortality associated with COPD.

Haemophilus influenzae in acute exacerbations of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common progressive respiratory disease that is associated with infective exacerbations that lead to worsening of symptoms. Many organisms are thought to trigger infective exacerbations, but Haemophilus influenzae is the most commonly isolated bacterium. The role of H. influenzae in infective exacerbations remains uncertain, mainly because the organism chronically colonises patients whose clinical condition is stable. H. influenzae may also comprise part of the normal nasopharyngeal flora in man, making the interpretation of positive cultures difficult in some cases.

Infections

Infection, in particular by respiratory viruses, plays an important role in triggering exacerbations and has also been implicated in the etiology of asthma and chronic obstructive pulmonary disease (COPD). This chapter reviews the epidemiological evidence that implicates infectious pathogens as triggers. The chapter also discusses the mechanisms of interaction between the host-pathogen response and preexisting airway pathology resulting in an exacerbation. Much of the treatment of infective exacerbations for both asthma and COPD is symptomatic, consisting of bronchodilators or supportive in the form of oxygen, and in severe cases it includes noninvasive or invasive ventilatory measures. The current therapy for virus-induced exacerbations of asthma and COPD relies on increased treatment of preexisting disease. Antibiotics are indicated for bacterial infections. The effective use of antiviral agents, particularly for influenza viruses, requires viral diagnosis, commencement of treatment early in the course of an exacerbation, or the targeting of high-risk groups for prophylaxis. Alternative strategies for drug development involve the identification of key factors common to exacerbations induced by a range of different viruses. Increased knowledge of the host–virus interaction can help in designing treatments that can increase virus clearance and minimize immunopathology.

Symptom resolution assessed using a patient directed diary card during treatment of acute exacerbations of chronic bronchitis

BACKGROUND

Acute exacerbations of chronic bronchitis are common and the presenting symptoms vary, although it is not clear how this should influence management. From a health care perspective, an understanding of the speed of symptom resolution is of importance to determine the success of treatment or when a change is indicated because of treatment failure.

METHODS

The response of 63 patients treated at home for exacerbations of chronic bronchitis was assessed using a patient directed diary card incorporating sputum characteristics and symptoms. Treatment was given according to the nature of the sputum at presentation; patients with purulent sputum received an antibiotic for 5 or 10 days (randomised, double blind) whereas patients with mucoid sputum received high dose inhaled steroid or placebo for 14 days (randomised, double blind).

RESULTS

The mean (SE) total diary card score at presentation was significantly higher in the purulent group than in the mucoid group (19.7 (0.9) v 16.3 (0.9); mean difference -3.4 (95% CI -6.1 to -0.7), p<0.05). In the purulent group sputum colour and volume improved rapidly and in both groups the mean (SE) total diary card score had improved by the fifth day of treatment to 13.0 (0.7) in the purulent group (mean difference -6.6 (95% CI -8.8 to -4.4), p<0.001) and 14.6 (0.8) in the mucoid group (mean difference -1.7 (95% CI -4.0 to 0.8), p<0.05), which was no longer significantly different from the stable state. Diary card scores did not differ significantly between patients who received antibiotics for 5 or 10 days in the purulent group or between patients who received inhaled fluticasone or placebo in the mucoid group.

CONCLUSIONS

Exacerbations of chronic bronchitis associated with purulent sputum have significantly worse symptoms at presentation than those with mucoid sputum. In both groups these symptoms resolve rapidly so that by the fifth day of treatment they are no different from the stable state. No significant effect was found on symptom resolution of antibiotic duration (5 v 10 days) in the purulent group or of inhaled fluticasone in the mucoid group, which resolved without antibiotics. Larger numbers may be required to demonstrate a statistically (if not clinically) significant difference.

Factors associated with relapse after ambulatory treatment of acute exacerbations of chronic bronchitis. DAFNE Study Group

This study aimed to identify the risk factors for relapse after ambulatory treatment of acute exacerbations of chronic bronchitis (AECB) that can easily be used in a primary care setting. Data were prospectively collected on 2,414 ambulatory patients with AECB from 268 general practices located throughout Spain. A multivariate model to identify risk factors independently associated with failures was developed and validated from the information recorded at the inclusion visit and at 30-days follow-up visit. A total of 507 patients relapsed (21%); of these, 84 required admission (16.5%). The multivariate model for prediction of the risk of relapse included 2,414 cases: 1,689 for the developmental sample and 725 in the validation sample. The model obtained contained three readily-obtainable variables: ischaemic heart disease (odds ratio (OR)=1.63; 95% confidence interval (CI)=1.07-2.47), degree of dyspnoea (OR = 1.31; 1.14-1.50) and number of visits to the general practitioner the previous year (OR = 1.07; 1.04-1.10). The model calibrated well in developmental and validation samples (goodness-of-fit tests: p = 0.295 and p = 0.637, respectively). Severity of the exacerbation was not associated with increased risk of relapse in either univariate or multivariate analysis. The present results suggest that baseline characteristics of the patients such as degree of dyspnoea, coexisting ischaemic heart disease and number of previous visits to the general practitioner for respiratory problems are strongly associated with increased risk of relapse after ambulatory treatment of acute exacerbations of chronic bronchitis. In contrast, exacerbation severity was not associated with clinical failure. Guidelines for management of acute exacerbations of chronic bronchitis should consider such risk factors and advocate intensive broad spectrum treatment and closer follow-up of patients exhibiting them.

Assessment of airway neutrophils by sputum colour: correlation with airways inflammation

BACKGROUND

Airway inflammation, with recruitment of neutrophils to the airway lumen, results in purulent secretions and a variety of potential adverse consequences for patients with chronic bronchitis and bronchiectasis. We hypothesised that gradations of sputum colour would correlate directly with the myeloperoxidase content of sputum and with various other indicators of the activity and consequences of bronchial diseases.

METHODS

To test this hypothesis, we quantified sputum colour by reference to a sensitive nine point colour chart and correlated this assessment with indices of a number of inflammatory mediators in sputum.

RESULTS

The results indicate that standardised visual measurements of sputum colour correlated strongly with myeloperoxidase, interleukin 8, leucocyte elastase (both activity and total quantity), sputum volume, protein leak, and secretory leucocyte proteinase inhibitor (p<0.001 for all). In addition, there was a strong direct correlation between leucocyte elastase and both myeloperoxidase (p<0.003) and sputum volume (p<0.001), but a strong negative correlation with secretory leucocyte proteinase inhibitor (p<0.001).

CONCLUSIONS

These results indicate that sputum colour graded visually relates to the activity of the underlying markers of bronchial inflammation. The results of this simple visual analysis of sputum provides guidance concerning underlying inflammation and its damaging potential. It also provides a useful scientific tool for improving the monitoring of chronic airways diseases and response to treatment.

Bacterial infection in chronic obstructive pulmonary disease in 2000: a state-of-the-art review

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States. The precise role of bacterial infection in the course and pathogenesis of COPD has been a source of controversy for decades. Chronic bacterial colonization of the lower airways contributes to airway inflammation; more research is needed to test the hypothesis that this bacterial colonization accelerates the progressive decline in lung function seen in COPD (the vicious circle hypothesis). The course of COPD is characterized by intermittent exacerbations of the disease. Studies of samples obtained by bronchoscopy with the protected specimen brush, analysis of the human immune response with appropriate immunoassays, and antibiotic trials reveal that approximately half of exacerbations are caused by bacteria. Nontypeable Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae are the most common causes of exacerbations, while Chlamydia pneumoniae causes a small proportion. The role of Haemophilus parainfluenzae and gram-negative bacilli remains to be established. Recent progress in studies of the molecular mechanisms of pathogenesis of infection in the human respiratory tract and in vaccine development guided by such studies promises to lead to novel ways to treat and prevent bacterial infections in COPD.