Changes in symptoms, peak expiratory flow, and sputum flora during treatment with antibiotics of exacerbations in patients with chronic obstructive pulmonary disease in general practice

Acute Exacerbations of COPD

This chapter explains the exacerbations of chronic obstructive pulmonary disease (COPD) and its causes, mechanisms, and treatment approaches. COPD exacerbations are an important cause of the significant morbidity and mortality related to COPD. These COPD exacerbations increase with severity of the disease, and frequent exacerbations impact the patient's quality of life and activities of daily living. These exacerbations are also associated with considerable physiological deterioration and increased airway inflammatory changes caused by a variety of factors such as viruses, bacteria, and some common pollutants. Exacerbation of COPD results in an increase in airflow obstruction, which further increases the load on the respiratory muscles and increases the effort in breathing, thereby leading to respiratory failure in severe cases. Treatment approaches include the use of corticosteroids, antibiotics, inhaled bronchodilator therapy in certain cases, and ventilatory support. Increased patient education about detecting and treating exacerbations early in the natural history of COPD can be significantly beneficial. Following an exacerbation, the patient's condition should be constantly reviewed, giving attention to risk factors and compliance with therapy.

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.

Relationship between asthma medication and antibiotic use

STUDY OBJECTIVES

Increasing morbidity due to asthma and antimicrobial resistance among human pathogens are both major public-health concerns. Numerous studies describe the overuse of antibiotics in general populations and underuse of anti-inflammatory medications by asthmatic patients. However, little is known about the relationship between asthma medication and antibiotic use in asthmatics. Specifically, we tested the hypothesis that higher use of bronchodilator and anti-inflammatory medication by asthmatics, as a marker of problematic asthma, is associated with greater antibiotic use. We also test the hypothesis that physicians who are low prescribers of anti-inflammatory medications are high prescribers of antibiotics.

DESIGN

We conducted a retrospective cohort study evaluating asthma medication and antibiotic use by children and adults with asthma and the prescribing of these medications by primary-care physicians.

SETTING/PATIENTS

Subjects were continuously enrolled asthma patients aged 6 to 55 years receiving care in an urban, group-model, health maintenance organization.

INTERVENTIONS

None.

MEASUREMENT AND RESULTS

Main outcome measures were (1) antibiotic use by asthmatics stratified by low, moderate, and high bronchodilator use; (2) antibiotic use by asthmatics stratified by no, intermittent, and long-term anti-inflammatory use; and (3) correlation between physician-level anti-inflammatory agent to bronchodilator ratio (AIF:BD) and their rate of antibiotic prescribing. We found that (1) high bronchodilator users received 1.72 antibiotics per person-year (95% confidence interval [CI], 1.62 to 1.83), whereas low bronchodilator users received 1.23 antibiotics per person-year (95% CI, 1.19 to 1.27; p < 0.0001); (2) long-term users of anti-inflammatory agents received 1.85 antibiotics per person-year (95% CI, 1.76 to 1.95), whereas those not receiving an anti-inflammatory agent received 0.95 antibiotics per person-year (95% CI, 0.90 to 1.00; p < 0.0001); and (3) despite variations in physician AIF:BDs and antibiotic prescribing, respectively, these measures were not correlated.

CONCLUSIONS

Antibiotic use and asthma medication use are positively associated in a cohort of asthma patients. Greater effort is needed to define the appropriate role of antibiotics in asthma management.

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.

Bacteria, antibiotics and COPD

Bacterial infection is one of several important causes of exacerbations of chronic obstructive pulmonary disease (COPD) that may coexist. COPD is a heterogeneous condition and the incidence of bacterial infection is not uniform; mucus hypersecretion may be an important risk factor. The bacteriology of infections varies depending on the severity of the underlying airway disease. There is now a much better understanding of the pathogenesis of bacterial infections of the respiratory mucosa. Lower airway bacterial colonization may be a stimulus for chronic inflammation and may influence the interval between exacerbations. Antibiotic resistance has increased in all the major pathogens. Antibiotics are an important part of the treatment of acute exacerbations of COPD and the decision about whether to give an antibiotic can be made on clinical grounds. It is more difficult to decide, on the available evidence, whether patient characteristics and the risk of antibiotic resistance should influence choice of empiric antibiotic treatment. Most new antibiotics are modifications of existing structures, suggesting that every effort should be made to conserve the sensitivity of current antibiotics by using them appropriately.

Management of acute exacerbations of COPD: a summary and appraisal of published evidence

STUDY OBJECTIVES

To critically review the available data on the diagnostic evaluation, risk stratification, and therapeutic management of patients with acute exacerbations of COPD.

DESIGN, SETTING, AND PARTICIPANTS

English-language articles were identified from the following databases: MEDLINE (from 1966 to week 5, 2000), EMBASE (from 1974 to week 18, 2000), HealthStar (from 1975 to June 2000), and the Cochrane Controlled Trials Register (2000, issue 1). The best available evidence on each subtopic then was selected for analysis. Randomized trials, sometimes buttressed by cohort studies, were used to evaluate therapeutic interventions. Cohort studies were used to evaluate diagnostic tests and risk stratification. Study design and results were summarized in evidence tables. Individual studies were rated as to their internal validity, external validity, and quality of study design. Statistical analyses of combined data were not performed.

MEASUREMENT AND RESULTS

Limited data exist regarding the utility of most diagnostic tests. However, chest radiography and arterial blood gas sampling appear to be useful, while short-term spirometry measurements do not. In terms of the risk of relapse and the risk of death after hospitalization for an acute exacerbation, there are identifiable clinical variables that are associated with these outcomes. Therapies for which there is evidence of efficacy include bronchodilators, corticosteroids, and noninvasive positive-pressure ventilation. There is also support for the use of antibiotics in patients with more severe exacerbations. Based on limited data, mucolytics and chest physiotherapy do not appear to be of benefit, and oxygen supplementation appears to increase the risk of respiratory failure in an identifiable subgroup of patients.

CONCLUSIONS

Although suggestions for appropriate management can be made based on available evidence, the supporting literature is spotty. Further high-quality research is needed and will require an improved, generally acceptable, and transportable definition of the syndrome "acute exacerbation of COPD" and improved methods for observing and measuring outcomes.

Antibiotics for acute asthma

BACKGROUND

Antibiotics are often prescribed to patients who are admitted to hospital with acute asthma. Their exacerbation is often precipitated by a viral upper respiratory infection (URTI), but in some instances antibiotics are prescribed in spite of questionable efficacy. A lack of strong evidence either to support or to refute the use of treatments in acute asthma leaves room for discussion and debate as to how effective antibiotics are in an acute setting. This review assesses what evidence is available.

OBJECTIVES

To determine the efficacy of antibiotics prescribed in the treatment of acute asthma

SEARCH STRATEGY

Electronic databases (MEDLINE, EMBASE and CINAHL) were searched to identify all possible randomised control trials.

SELECTION CRITERIA

Only RCTs or quasi RCTs were eligible for inclusion. Studies were included if patients were treated for acute asthma in the ED or its equivalent with antibiotics or placebo. Two reviewers independently assessed articles for potential relevance, final inclusion, and methodological quality.

DATA COLLECTION AND ANALYSIS

Two reviewers completed trial quality assessment and data extraction independently.

MAIN RESULTS

From 128 potential studies, two trials were identified for inclusion in the review. Both trials reported numbers of exacerbations and not patient numbers due to re admissions over the course of the trials. The total number of patients in this review was 97, but values were recorded for 115 exacerbations.

REVIEWER'S CONCLUSIONS

The role of antibiotics in the treatment of acute asthma is difficult to assess from the current literature. Recommendations regarding antibiotic use in acute asthma will remain consensus driven until more research is conducted which includes larger numbers of patients.

YM-40461, a potent surfactant secretagogue, improves mucociliary clearance in SO2-exposed guinea pigs

The effects of the new pulmonary surfactant secretagogue YM-40461, 1-(2-dimethylaminoethyl)-1-(3,4,5-trimethoxyphenyl) urea, on tracheal mucociliary transport (MCT) were assessed using guinea pigs with acute bronchitis. Acute bronchitis was induced by SO2 gas exposure (400 ppm for 3 h). MCT velocity was measured by means of the dye gelatin technique. YM-40461 at doses of 1-10 mg/kg, p.o. induced recovery of MCT function, with an ED50 value of 2.4 mg/kg. Maximal recovery (78.0+/-12.5%) was observed 2 h in the animals treated with 10 mg/kg of YM-40461. Ambroxol and bromhexine showed less effect on the MCT dysfunction than YM-40461. An artificial surfactant (Surfacten) also aided recovery. YM-40461 at a dose of 10 mg/kg, p.o. significantly improved surfactant production without affecting mucus secretion. These results show that YM-40461 ameliorates MCT dysfunction caused by SO2 exposure by activation of pulmonary surfactant secretion.

Do bacteria cause exacerbations of COPD?

Exacerbations of COPD, which include combinations of dyspnea, cough, wheezing, increased sputum production (and a change in its color to green or yellow), are common. The role of bacterial infection in causing these episodes and the value of antibiotic therapy for them are debated. An assessment of the microbiological studies indicates that conventional bacterial respiratory pathogens, such as Streptococcus pneumoniae and Haemophilus influenzae, are absent in about 50% of attacks. The frequency of isolating these organisms, which often colonize the bronchi of patients in stable condition, does not seem to increase during exacerbations, and their density typically remains unchanged. Serologic studies generally fail to show rises in antibody titers to H influenzae; the only report available demonstrates none to Haemophilus parainfluenzae; and the sole investigation of S pneumoniae is inconclusive. Trials with vaccines against S pneumoniae and H influenzae show no clear benefit in reducing exacerbations. The histologic findings of bronchial biopsies and cytologic studies of sputum show predominantly increased eosinophils, rather than neutrophils, contrary to what is expected with bacterial infections. The randomized, placebo-controlled trials generally show no benefit for antibiotics, but most have studied few patients. A meta-analysis of these demonstrated no clinically significant advantage to antimicrobial therapy. The largest trials suggest that antibiotics confer no advantage for mild episodes; with more severe attacks, in which patients should receive systemic corticosteroids, the addition of antimicrobial therapy is probably not helpful.

Time course and recovery of exacerbations in patients with chronic obstructive pulmonary disease

Although exacerbations of chronic obstructive pulmonary disease (COPD) are associated with symptomatic and physiological deterioration, little is known of the time course and duration of these changes. We have studied symptoms and lung function changes associated with COPD exacerbations to determine factors affecting recovery from exacerbation. A cohort of 101 patients with moderate to severe COPD (mean FEV(1) 41.9% predicted) were studied over a period of 2.5 yr and regularly followed when stable and during 504 exacerbations. Patients recorded daily morning peak expiratory flow rate (PEFR) and changes in respiratory symptoms on diary cards. A subgroup of 34 patients also recorded daily spirometry. Exacerbations were defined by major symptoms (increased dyspnea, increased sputum purulence, increased sputum volume) and minor symptoms. Before onset of exacerbation there was deterioration in the symptoms of dyspnea, sore throat, cough, and symptoms of a common cold (all p < 0.05), but not lung function. Larger falls in PEFR were associated with symptoms of increased dyspnea (p = 0.014), colds (p = 0.047), or increased wheeze (p = 0.009) at exacerbation. Median recovery times were 6 (interquartile range [IQR] 1 to 14) d for PEFR and 7 (IQR 4 to 14) d for daily total symptom score. Recovery of PEFR to baseline values was complete in only 75.2% of exacerbations at 35 d, whereas in 7.1% of exacerbations at 91 d PEFR recovery had not occurred. In the 404 exacerbations where recovery of PEFR to baseline values was complete at 91 d, increased dyspnea and colds at onset of exacerbation were associated with prolonged recovery times (p < 0.001 in both cases). Symptom changes during exacerbation do not closely reflect those of lung function, but their increase may predict exacerbation, with dyspnea or colds characterizing the more severe. Recovery is incomplete in a significant proportion of COPD exacerbations.

Prescribing habits of general practitioners in choosing an empirical antibiotic regimen for lower respiratory tract infections in adults in Sicily

The survey was carried out, between September 1995 and May 1996, in order to describe the prescriptive behaviour among Sicilian general practitioners (GPs) in choosing an empirical antibiotic regimen for LRTIs in adult patients and begin an educational process which involves the same GPs in decisions regarding their prescriptions and in performing local guidelines. Each practitioner filled out a questionnaire for each therapeutic intervention which ended with an antibiotic prescription. The questionnaire also enquired into the patient's characteristics, diseases to be treated and drug prescription. Doctors were asked to give an opinion about the severity assessment of the infectious disease before choosing the antibiotic treatment, in order to evaluate the prescriptive behaviour of physicians related to the patient's symptoms. Of all Sicilian GPs approached, 76 physicians from 25 Sicilian towns, with a patient population of 96,630, agreed to participate. The GPs used 49 different molecules and six different associations of two antibiotics. The most frequently used antibacterial agents were cephalosporins (55.0%). Penicillins (11.7%), fluoroquinolones (11. 4%), macrolides (10.1%) and combinations of penicillins with beta-lactamase inhibitors (7.9%), together, represented 41.1% of the remaining antibiotic prescriptions. The choice of the route of administration was significantly influenced by age of the patients, by symptoms and signs of the disease and by the presence of concurrent diseases rather than by bacteria suspected of causing the disease. The rather marked variation in antibiotic prescribing pattern for LRTIs among Sicilian GPs reflects lack of availability or knowledge of any local or national guidelines about the management of these diseases.

Relationship between bacterial flora in sputum and functional impairment in patients with acute exacerbations of COPD. Study Group of Bacterial Infection in COPD

STUDY OBJECTIVES

To investigate the possible relationship between functional respiratory impairment measured by FEV1 and isolation of diverse pathogens in the sputum of patients with exacerbations of COPD.

DESIGN

Multicenter, cross-sectional, epidemiologic study.

SETTING

Pneumology units in six secondary or tertiary hospitals in Spain.

PATIENTS

Ninety-one patients with acute exacerbation of COPD were included.

INTERVENTIONS

A quantitative sputum culture was performed, and bacterial growth was considered significant only when the germ was isolated at concentrations > 10(6) cfu (> 10(5) for Streptococcus pneumoniae) in samples with < 10 epithelial cells and > 25 leukocytes per low magnification field (x 100).

RESULTS

Germs isolated were the following: Haemophilus influenzae (20 cases; 22%), Pseudomonas aeruginosa (14 cases; 15%), S. pneumoniae (9 cases; 10%), Moraxella catarrhalis (8 cases; 9%), other gram-negative bacteria (7 cases; 7%), and non-potentially pathogenic microorganisms (non-PPMs; 33 cases; 36%). P. aeruginosa and H. influenzae were isolated more frequently among the patients with FEV1 < 50% than among those with FEV1 > 50% (p < 0.05). All patients with P. aeruginosa in sputum had FEV1 < 1,700 mL. FEV1 < 50% was associated with a very high risk of P. aeruginosa or H. influenzae isolation: the odds ratios (ORs) are 6.62 (95% confidence interval [CI], 1.2 to 123.6) and 6.85 (95% CI, 1.6 to 52.6), respectively. Furthermore, active tobacco smoking was associated with a high risk of H. influenzae isolation (OR, 8.1; 95% CI, 1.9 to 43.0).

CONCLUSIONS

Patients with the greatest degree of functional impairment, as measured by their FEV1, presented a higher probability of having an isolation of P. aeruginosa or H. influenzae in significant concentrations in sputum during an exacerbation. The diagnostic yield of sputum in patients with an FEV1 > 50% was low, with a predominance of non-PPMs. Low FEV1 and active tobacco smoking are data that should be considered when establishing an empiric antibiotic treatment for exacerbated COPD.

Treatment of chronic obstructive pulmonary disease and its exacerbations in general practice. EOLO Group. Estudio Observacional de la Limitación Obstructiva al Flujo aEreo

The high prevalence and chronicity of chronic obstructive pulmonary disease (COPD) imply that many of these patients are treated and controlled in primary-care centres, often without contact with specialized pneumologist care. We conducted the present study to evaluate the treatment administered in stable and exacerbated COPD in GP-setting clinics and to investigate which factors could be associated with the different prescriptions. This is a cross-sectional observational study of ambulatory COPD patients. General practitioners (n = 201) were selected throughout Spain by regionally stratified sampling. We recorded the physician-reported prescription drug use in ambulatory treatment of stable COPD and acute exacerbations of COPD through a standard questionnaire. Factors independently associated with the prescription of drugs were ascertained by multiple logistic regression analysis. Of 1078 questionnaires reviewed, 1001 fulfilled quality criteria. There were 878 men (88%) and 123 women (12%); 777 (78%) were smokers or ex-smokers with a mean age of 68 years. Mean FEV1 was 47% predicted (% pred.) (SD = 13%). The median number of exacerbations was two per year (range = 0-16). Regular treatment for COPD was received by 878 (88%): the most commonly used drugs were inhaled beta 2-agonists (71%), theophyllines (53%) and inhaled corticosteroids (ICs) (50%), followed by mucolytics (25%), ipratropium bromide (23%), and oral corticosteroids (OCs) (4%). Treatment for exacerbations included inhaled bronchodilators (90%), antibiotics (89%), ICs (71%) and OCs (43%). Impairment of FEV1 was the factor most strongly associated in multiple regression analysis with increasing drug prescription in stable COPD, except for mucolytics, while the number of previous acute exacerbations was the main factor associated with exacerbation treatment except for OCs, the use of which was associated with more impaired pulmonary function. A significant number of the treatments prescribed in primary care for stable and exacerbated COPD do not follow current recommendations. Impairment in FEV1 is the factor most strongly associated with increasing prescription in stable COPD and the number of previous exacerbations is the main factor associated with exacerbation treatment.

The value of antibiotics and the outcomes of antibiotic therapy in exacerbations of COPD

COPD is the fifth leading cause of death in the United States, and acute respiratory infections account for a significant proportion of all primary care visits. Approximately one half of all exacerbations of COPD can be attributed to bacterial infection, and antibiotic therapy has been demonstrated to improve clinical outcomes and hasten clinical and physiologic recovery. The major pathogen continues to be Haemophilus influenzae, and resistance to beta-lactam antibiotics such as ampicillin can be expected in 20 to 40% of isolated strains. Certain high-risk patients, in whom the cost of clinical treatment failure is high, can be identified by simple clinical criteria. Patients with significant cardiopulmonary comorbidity, frequent purulent exacerbations of COPD, advanced age, generalized debility, malnutrition, chronic corticosteroid administration, long duration of COPD, and severe underlying lung function tend to fail therapy with older drugs, such as ampicillin, and early relapse can be expected. Treatment directed toward resistant pathogens with potent bactericidal drugs may be expected to lead to improved clinical outcomes and overall lower costs, particularly if hospital admissions and respiratory failure can be prevented. Future studies examining the role of antibiotics should enroll these high-risk patients to determine if new therapies have significant clinical, quality-of-life, and economic advantages over older agents.

The role of infection in COPD

Clinical studies of acute exacerbations of COPD are difficult because of the heterogeneous nature of COPD, diffuse symptoms that can vary spontaneously, and difficulties in defining clinical response both in the short and long term. The role of bacterial infection, and thus use of antibiotics, in COPD is controversial. The available evidence shows that bacterial infection has a significant role in acute exacerbations, but its role in disease progression is less certain. Upper respiratory tract commensals, such as nontypable Haemophilus influenzae, cause most bronchial infections by exploiting deficiencies in the host defenses. Some COPD patients are chronically colonized by bacteria between exacerbations, which represents an equilibrium in which the numbers of bacteria are contained by the host defenses but not eliminated. When an exacerbation occurs, this equilibrium is upset and bacterial numbers increase, which incites an inflammatory response. Neutrophil products can further impair the mucosal defenses, favoring the bacteria, but if the infection is overcome, symptoms resolve. However, if the infection persists, chronic inflammation may cause lung damage. About half of exacerbations involve bacterial infection, but these patients are not easy to differentiate from those who are uninfected, which means that antibiotics have to be given more often than is strictly necessary. Further research is needed to characterize those patients in whom bacterial infection has a more important role.

Effect of dirithromycin on Haemophilus influenzae infection of the respiratory mucosa

Macrolides have properties other than their antibiotic action which may benefit patients with airway infections. We have investigated the effect of dirithromycin (0.125 to 8.0 microg/ml) on the interaction of Haemophilus influenzae with respiratory mucosa in vitro using human nasal epithelium, adenoid tissue, and bovine trachea. Dirithromycin did not affect the ciliary beat frequency of the nasal epithelium or the transport of mucus on bovine trachea, but dirithromycin (1 microg/ml) did reduce the slowing of the ciliary beat frequency and the damage to the nasal epithelium caused by H. influenzae broth culture filtrate. Amoxicillin (2 microg/ml) did not reduce the effects of the H. influenzae broth culture filtrate. H. influenzae infection of the organ cultures for 24 h caused mucosal damage and the loss of ciliated cells. Bacteria adhered to damaged epithelium and to a lesser extent to mucus and unciliated cells. Incubation of H. influenzae with dirithromycin at sub-MICs (0.125 and 0.5 microg/ml) prior to infection of the organ cultures did not reduce the mucosal damage caused by bacterial infection. By contrast, incubation of adenoid tissue with dirithromycin (0.125 to 1.0 microg/ml) for 4 h prior to assembling the organ culture reduced the mucosal damage caused by subsequent H. influenzae infection by as much as 50%. The number of bacteria adherent to the mucosa was reduced, although the tissue that had been incubated with dirithromycin (0.125 and 0.5 microg/ml) did not inhibit bacterial growth. This was achieved by a reduction in the amount of damaged epithelium to which H. influenzae adhered and a reduction in the density of bacteria adhering to mucus. We conclude that dirithromycin at concentrations achievable in vivo markedly reduces the mucosal damage caused by H. influenzae infection due to a cytoprotective effect.

Pharmacological treatment in acute exacerbations of chronic obstructive pulmonary disease

Exacerbations of chronic obstructive pulmonary disease (COPD) are usually treated with bronchodilator therapy, glucocorticoids and antibiotics. However, there are few experimental data on the effects of these agents in patients with acute COPD. A beta(2)-adrenoceptor agonist is usually given first because it can be expected to produce a rapid response. An anticholinergic agent should also be given when the patient is severely ill or responds inadequately to the beta(2) agonist. These agents can be administered via a nebuliser or using a metered-dose inhaler in conjunction with a spacer device. Glucocorticoids can accelerate recovery if the standard empirical regimens for acute exacerbations of asthma are used, although a longer treatment duration appears to be required. Theophylline provides little additional benefit in patients who receive frequent doses of inhaled bronchodilators and an adequate dosage of a glucocorticoid. Although the role of bacterial infections is not completely understood, the use of antibiotics is justified in patients with severe airflow limitation who have febrile tracheobronchitis.

[Protected bacteriologic brushing in patients with severe copd]

To determine the presence of germs and their concentration in a group of patients with severe chronic obstructive pulmonary disease (COPD) (FEV1 < 50%), some of whom were in stable condition and others of whom were in acute phase. Twenty-six patients with severe COPD (14 stable and 12 acute phase) were enrolled. None had received prior antibiotic or corticoid treatment. The stable patients had no signs or symptoms of exacerbation, whereas the acute-phase patients had increased dyspnea, sputum volume and purulence. The patients received aerosol rather than liquid anesthesia when PSB sampling was performed. A PSB finding was considered positive at a level > or = 10(3) CFU/ml. There were no significant differences between the groups with respect to age, sex, proportion of smokers and ex-smokers or packs per year. The only spirometric measure that was significantly different was (FEV1/FVC, which was lower in the acute-phase group (p < 0.05). Positive PSB findings were recorded for 57.1% of the stable patients and for 66.7% of the acute-phase patients (p = NS). H. influenzae was the microorganism found most often in both groups. The mean CFU/ml level was 8,625 in stable patients and 17,375 in acute-phase patients (p = NS). A large proportion of stable patients (57.1%) with severe COPD harbor significant concentrations of germs as revealed by PSB sampling. Germ concentrations were found in a non significantly greater number of acute-phase patients, confirming the lack of congruence between clinical status and bacteriological condition.