Infections and airway inflammation in chronic obstructive pulmonary disease severe exacerbations

RATIONALE: Severe exacerbations of chronic obstructive pulmonary disease (COPD) are major causes of health care costs mostly related to hospitalization. The role of infections in COPD exacerbations is controversial. OBJECTIVES: We investigated whether COPD exacerbations requiring hospitalization are associated with viral and/or bacterial infection and evaluated relationships among infection, exacerbation severity, assessed by reduction of FEV1, and specific patterns of airway inflammation. METHODS: We examined 64 patients with COPD when hospitalized for exacerbations, and when in stable convalescence. We measured lung function, blood gases, and exhaled nitric oxide, and examined sputum for inflammation and for viral and bacterial infection. RESULTS: Exacerbations were associated with impaired lung function (p < 0.01) and increased sputum neutrophilia (p < 0.001). Viral and/or bacterial infection was detected in 78% of exacerbations: viruses in 48.4% (6.2% when stable, p < 0.001) and bacteria in 54.7% (37.5% when stable, p = 0.08). Patients with infectious exacerbations (29.7% bacterial, 23.4% viral, 25% viral/bacterial coinfection) had longer hospitalizations (p < 0.02) and greater impairment of several measures of lung function (all p < 0.05) than those with noninfectious exacerbations. Patients with exacerbations with coinfection had more marked lung function impairment (p < 0.02) and longer hospitalizations (p = 0.001). Sputum neutrophils were increased in all exacerbations (p < 0.001) and were related to their severity (p < 0.001), independently of the association with viral or bacterial infections; sputum eosinophils were increased during (p < 0.001) virus-associated exacerbations. CONCLUSIONS: Respiratory infections are associated with the majority of COPD exacerbations and their severity, especially those with viral/bacterial coinfection. Airway neutrophilia is related to exacerbation severity regardless of viral and/or bacterial infections. Eosinophilia is a good predictor of viral exacerbations.     

Treatment principle of the chronic obstructive pulmonary disease (COPD) exacerbation

COPD is often accompanied with acute symptoms exacerbations. Patients in Ist stage: slide grade of COPD and IInd stage: middle grade of COPD suffer exacerbations accompanied with increased dyspnoea often together with increased cough and increased production of sputum. Patients in IIIrd stage (serious) and IVth stage (very serious) experience during exacerbations development of respiration insufficiency or its worsening and thus are usually treated in hospital. The most frequent causes of exacerbations are tracheobronchial tree infections and air pollution. The cause of approximately one third of serious exacerbations is not disclosed. Conditions which can resemble acute exacerbation are pneumonia, congestive heart failure, pneumothorax, pleural exudation, pulmonary embolism, and arrhythmia. Exacerbation treatment is symptomatic. Obstruction symptoms are treated with bronchodilatants and corticosteroids administration, hypoxemia with oxygen administration and signs of bacterial infection with antibiotics.     

Pseudomonal infections in patients with COPD: epidemiology and management

COPD is a common disease with increasing prevalence. The chronic course of the disease is characterized by acute exacerbations that cause significant worsening of symptoms. Bacterial infections play a dominant role in approximately half of the episodes of acute exacerbations of COPD. The importance of pseudomonal infection in patients with acute exacerbations of COPD stems from its relatively high prevalence in specific subgroups of these patients, and particularly its unique therapeutic ramifications. The colonization rate of Pseudomonas aeruginosa in patients with COPD in a stable condition is low.A review of a large number of clinical series of unselected outpatients with acute exacerbations of COPD revealed that P. aeruginosa was isolated from the patients' sputum at an average rate of 4%. This rate increased significantly in COPD patients with advanced airflow obstruction, in whom the rate of sputum isolates of P. aeruginosa reached 8-13% of all episodes of acute exacerbations of COPD. However, the great majority of bacteria isolated in these patients were not P. aeruginosa, but the three classic bacteria Streptococcus pneumoniae, Hemophilus influenzae, and Moraxella catarrhalis. The subgroup of patients, with acute exacerbations of COPD, with the highest rate of P. aeruginosa infection, which approaches 18% of the episodes, is mechanically ventilated patients. However, even in this subgroup the great majority of bacteria isolated are the above-mentioned three classic pathogens. In light of these epidemiologic data and other important considerations, and in order to achieve optimal antibacterial coverage for the common infectious etiologies, empiric antibacterial therapy should be instituted as follows. Patients with acute exacerbations of COPD with advanced airflow obstruction (FEV(1) <50% of predicted under stable conditions) should receive once daily oral therapy with one of the newer fluoroquinolones, i.e. levofloxacin, moxifloxacin, gatifloxacin, or gemifloxacin for 5-10 days. Patients with severe acute exacerbations of COPD who are receiving mechanical ventilation should receive amikacin in addition to one of the intravenous preparations of the newer fluoroquinolones or monotherapy with cefepime, a carbapenem or piperacillin/tazobactam. In both subgroups it is recommended that sputum cultures be performed before initiation of therapy so that the results can guide further therapy.     

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

STUDY OBJECTIVES: To stratify COPD patients presenting with an acute exacerbation on the basis of sputum color and to relate this to the isolation and viable numbers of bacteria recovered on culture. DESIGN: Open, longitudinal study of sputum characteristics and acute-phase proteins. SETTING: Patients presenting to primary-care physicians in the United Kingdom. Patients were followed up as outpatients in specialist clinic. PATIENTS: One hundred twenty-one patients with acute exacerbations of COPD were assessed together with a single sputum sample on the day of presentation (89 of whom produced a satisfactory sputum sample for analysis). One hundred nine patients were assessed 2 months later when they had returned to their stable clinical state. INTERVENTIONS: The expectoration of green, purulent sputum was taken as the primary indication for antibiotic therapy, whereas white or clear sputum was not considered representative of a bacterial episode and the need for antibiotic therapy. RESULTS: A positive bacterial culture was obtained from 84% of patients sputum if it was purulent on presentation compared with only 38% if it was mucoid (p < 0.0001). When restudied in the stable clinical state, the incidence of a positive bacterial culture was similar for both groups (38% and 41%, respectively). C-reactive protein concentrations were significantly raised (p < 0.0001) if the sputum was purulent (median, 4.5 mg/L; interquartile range [IQR], 6. 2 to 35.8). In the stable clinical state, sputum color improved significantly in the group who presented with purulent sputum from a median color number of 4.0 (IQR, 4.0 to 5.0) to 3.0 (IQR, 2.0 to 4. 0; p < 0.0001), and this was associated with a fall in median C-reactive protein level to 2.7 mg/L (IQR, 1.0 to 6.6; p < 0.0001). CONCLUSIONS: The presence of green (purulent) sputum was 94.4% sensitive and 77.0% specific for the yield of a high bacterial load and indicates a clear subset of patient episodes identified at presentation that is likely to benefit most from antibiotic therapy. All patients who produced white (mucoid) sputum during the acute exacerbation improved without antibiotic therapy, and sputum characteristics remained the same even when the patients had returned to their stable clinical state.     

Granulocyte inflammatory markers and airway infection during acute exacerbation of chronic obstructive pulmonary disease

There is increasing evidence that chronic obstructive pulmonary disease (COPD) is associated with chronic inflammation in the airways and lung parenchyma; however, little is known about the inflammatory response during acute COPD exacerbation. The objectives of this study were (1) to determine if inflammatory markers associated with neutrophilic inflammation and activation increase at times of acute COPD exacerbation relative to the clinically stable state, and (2) to determine whether the presence of acute bacterial or viral infection at the time of COPD exacerbation could be correlated with increases in sputum markers of inflammation. Induced sputum was collected from patients with COPD when they were clinically stable, during the time of an acute exacerbation, and 1 mo later. Sputum was analyzed at each time point for soluble markers associated with neutrophilic inflammation; myeloperoxidase (MPO), tumor necrosis factor-alpha (TNF-alpha), and interleukin-8 (IL-8). Serologic assays on acute and convalescent sera were performed for respiratory viruses, and induced sputum was also subject to quantitative bacterial cultures, viral cultures, and polymerase chain reaction (PCR) for detection of respiratory viruses. Fourteen of the 50 patients enrolled in the study met predetermined criteria for an acute COPD exacerbation over the 15-mo study period. TNF-alpha and IL-8 were significantly elevated in the sputum of patients during acute COPD exacerbation compared with when they were clinically stable (p = 0.01 and p = 0.05, respectively). Concentrations of these cytokines declined significantly 1 mo after the exacerbation. Three of 14 patients (21%) had confirmed bacterial or viral respiratory tract infections. Patients with documented infection did not demonstrate greater increases in sputum levels of inflammatory cytokines during exacerbations compared with patients without demonstrable infection. We conclude that markers of airway neutrophilic inflammation increase at the time of acute COPD exacerbation and then decline 1 mo later, and that this acute inflammatory response appears to occur independently of a demonstrable viral or bacterial airway infection.     

Influence of beclomethasone dipropionate inhalation therapy on respiratory bacterial infection in patients with an acute exacerbation of COPD]

The aim of this clinical study was to investigate the influence of beclomethasone dipropionate (BDP) inhalation therapy on respiratory bacterial infections in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). We studied 30 patients who had been admitted twice, (before and after the beginning BDP inhalation therapy) to our hospital because of an exacerbation of COPD by respiratory tract infection. No differences were observed before and after BDP inhalation therapy in values for PaO2, PaCO2, body temperature, CRP, WBC count, number of admission days, and bacterial culture of sputum on admission. These results suggest that BDP inhalation therapy has little influence on respiratory bacterial infection during exacerbation of COPD.     

Acute purulent exacerbation of chronic obstructive pulmonary disease and Chlamydia pneumoniae infection.

In order to investigate the role of bacteria, including Mycoplasma pneumoniae and especially Chlamydia pneumoniae in acute purulent exacerbations of chronic obstructive pulmonary disease (COPD), we examined sputum specimens and acute and convalescent sera taken 26 d apart from 49 outpatients experiencing an acute purulent exacerbation of COPD. The sera were tested for antibodies to C. pneumoniae with the microimmunofluorescence test, and for antibodies to M. pneumoniae with the indirect fluorescence antibody test. Routine microbiologic culture of sputum yielded potentially pathogenic microorganisms in 12 of the 49 patients (24%). Three patients (6%) showed serologic evidence of recent M. pneumoniae infection. Seven patients showed high IgG titers of >/= 1:1,024 to C. pneumoniae, and an additional four had a fourfold increase in IgG titer, suggesting reinfection with C. pneumoniae. Sputum from two of these 11 patients also grew Streptococcus pneumoniae, and one grew Moraxella catarrhalis. Patients with and without serologic evidence of current C. pneumoniae infection showed no significant differences in clinical features or pulmonary function. The high incidence of infection with C. pneumoniae (the sole causal agent in 16% of cases, and the causal agent with other agents in 6%) provides insight into the importance of this organism among agents leading to exacerbations of COPD in Turkey.     

COPD急性加重期肺炎衣原体感染的临床分析

目的　了解肺炎衣原体急性感染在 COPD急性加重期患者中的发生率及其临床特点。方法　采用固相酶联免疫吸附试验 EL ISA法测定 96例 COPD急性加重期患者血清肺炎衣原体特异性抗体 Ig G及 Ig M,同时进行痰培养 ,急性肺炎衣原体感染者分别给予阿奇霉素及左氧氟沙星治疗。结果　 COPD患者急性肺炎衣原体感染率 2 5 .0 % ,临床表现较其他 COPD患者无明显特征性 (P>0 .0 5 )。COPD患者痰细菌阳性率 5 8.3%。左氧氟沙星对肺炎衣原体急性感染的 COPD患者疗效良好。结论　 COPD急性加重期患者中肺炎衣原体急性感染率高且混合感染率多见 ,合并肺炎衣原体急性感染的 COPD患者临床表现无明显特征性。对于怀疑合并肺炎衣原体感染的COPD患者 ,新喹诺酮类药物可用作早期经验性治疗的药物。     

Pseudomonal Infections in Patients with COPD

COPD is a common disease with increasing prevalence. The chronic course of the disease is characterized by acute exacerbations that cause significant worsening of symptoms. Bacterial infections play a dominant role in approximately half of the episodes of acute exacerbations of COPD. The importance of pseudomonal infection in patients with acute exacerbations of COPD stems from its relatively high prevalence in specific subgroups of these patients, and particularly its unique therapeutic ramifications. The colonization rate of Pseudomonas aeruginosa in patients with COPD in a stable condition is low.A review of a large number of clinical series of unselected outpatients with acute exacerbations of COPD revealed that P. aeruginosa was isolated from the patients’ sputum at an average rate of 4%. This rate increased significantly in COPD patients with advanced airflow obstruction, in whom the rate of sputum isolates of P. aeruginosa reached 8–13% of all episodes of acute exacerbations of COPD. However, the great majority of bacteria isolated in these patients were not P. aeruginosa, but the three classic bacteria Streptococcus pneumoniae, Hemophilus influenzae, and Moraxella catarrhalis. The subgroup of patients, with acute exacerbations of COPD, with the highest rate of P. aeruginosa infection, which approaches 18% of the episodes, is mechanically ventilated patients. However, even in this subgroup the great majority of bacteria isolated are the above-mentioned three classic pathogens.In light of these epidemiologic data and other important considerations, and in order to achieve optimal antibacterial coverage for the common infectious etiologies, empiric antibacterial therapy should be instituted as follows. Patients with acute exacerbations of COPD with advanced airflow obstruction (FEV₁ <50% of predicted under stable conditions) should receive once daily oral therapy with one of the newer fluoroquinolones, i.e. levofloxacin, moxifloxacin, gatifloxacin, or gemifloxacin for 5–10 days. Patients with severe acute exacerbations of COPD who are receiving mechanical ventilation should receive amikacin in addition to one of the intravenous preparations of the newer fluoroquinolones or monotherapy with cefepime, a carbapenem or piperacillin/tazobactam. In both subgroups it is recommended that sputum cultures be performed before initiation of therapy so that the results can guide further therapy.     

Chlamydia pneumoniae, strain TWAR, infection in patients with chronic obstructive pulmonary disease.

TWAR, the only known serovar of Chlamydia pneumoniae, is a newly described bacterium that has been identified as a cause of both epidemics and endemic cases of pneumonia. The role of TWAR infection in patients with chronic obstructive pulmonary disease (COPD) is not known. We conducted a prospective study to establish whether TWAR infection is a common cause of acute exacerbations of COPD. We studied two groups of patients: 44 patients admitted to the hospital with acute exacerbations of COPD, and 65 stable clinic patients with COPD. We found that evidence of acute TWAR infection was infrequent in patients with exacerbations (5%). In contrast, the majority of patients from both groups had serologic evidence of previous TWAR infection (77%). This was not significantly greater than the prevalence found in a small group of patients of similar age and sex without lung disease from the same institution (73%). TWAR was not isolated from the oropharyngeal specimens obtained from 97 subjects, suggesting that it does not colonize the respiratory tract of patients with COPD. This study shows that at the time of low incidence in the community, acute TWAR infection is uncommon in patients with acute exacerbations of COPD. The majority of patients with COPD have, however, been infected with TWAR in the past. The clinical manifestations of these infections are not known and should be the focus of further studies.     

Effect of interactions between lower airway bacterial and rhinoviral infection in exacerbations of COPD

STUDY OBJECTIVES: The inflammatory responses and associated clinical severity of COPD exacerbations are greatly variable, and the determinants of these factors are poorly understood. We examined the hypothesis that bacteria and viruses may modulate this heterogeneity and that interactions between bacterial and viral infection may affect changes in airway bacterial load and the clinical features and inflammatory responses of exacerbations in patients with COPD. DESIGN: Prospective cohort study. SETTING: Outpatient Department, London Chest Hospital, London, UK. PATIENTS: Thirty-nine patients with COPD. MEASUREMENTS: We prospectively studied 56 COPD exacerbations, obtaining clinical data and paired sputum and serum samples at baseline and exacerbation. Qualitative and quantitative microbiology, polymerase chain reaction detection for rhinovirus, and estimation of cytokine levels by enzyme-linked immunosorbent assay were performed. RESULTS: A total of 69.6% of exacerbations were associated with a bacterial pathogen, most commonly Haemophilus influenzae. Rhinovirus was identified in 19.6% of exacerbations. The rise in bacterial load at exacerbation correlated with the rise in sputum interleukin (IL)-8 (r = 0.37, p = 0.022) and fall in FEV1 (r = 0.35, p = 0.048). Exacerbations with both rhinovirus and H. influenzae had higher bacterial loads (10(8.56) cfu/mL vs 10(8.05)cfu/mL, p = 0.018) and serum IL-6 (13.75 pg/mL vs 6.29 pg/mL, p = 0.028) than exacerbations without both pathogens. In exacerbations with both cold symptoms (a marker of putative viral infection) and a bacterial pathogen, the FEV1 fall was greater (20.3% vs 3.6%, p = 0.026) and symptom count was higher (p = 0.019) than those with a bacterial pathogen alone. CONCLUSIONS: The clinical severity and inflammatory responses in COPD exacerbations are modulated by the nature of the infecting organism: bacterial and viral pathogens interact to cause additional rises in inflammatory markers and greater exacerbation severity.     

Bacterial infection and risk factors in outpatients with acute exacerbation of chronic obstructive pulmonary disease: a 2-year prospective study

BACKGROUND AND OBJECTIVES: Acute exacerbations of COPD (AECOPD) are commonly observed in community-based patients worldwide. The factors causing exacerbation are largely unknown. This study was undertaken to determine the predominant bacterial pathogens cultured from sputum in community-based patients with AECOPD, to assess the risk factors associated with exacerbations and to compare these findings with published studies. METHODS: Forty-five patients with stable COPD were prospectively followed in the outpatients' clinic of King Abdulaziz University Hospital. At the first visit, personal data, CXR and measurement of baseline PEF were obtained from each patient. In the subsequent visits, sputum culture and CXR were carried out during exacerbations. RESULTS: Over a period of 24 months, patients made a total of 139 visits for exacerbations, and 69.8% had a positive sputum culture for a single pathogen. Moraxella catarrhalis (25.2%), Pseudomonas aeruginosa (12.2%) and Haemophilus influenzae (11.5%) were the most common isolated organisms. Patients with a lower level of baseline PEF had a significantly increased frequency of exacerbations (r = 0.337, P = 0.024). However, there was a weak correlation between exacerbation frequency and duration of COPD and exposure to cigarette smoking. CONCLUSION: There was a higher incidence of Moraxella catarrhalis and Pseudomonas aeruginosa than reported in previous studies. These findings should influence antibiotic selection for exacerbations. COPD patients with a low baseline PEF are at a higher risk of having repeated exacerbations and gram-negative pathogens.     

Role of bacteria in acute exacerbations of chronic obstructive pulmonary disease

Background and study objective

Infections are major causes of acute exacerbations of chronic obstructive pulmonary disease (COPD) which result in significant mortality and morbidity. The primary aim of the study was to determine the microbiological spectrum including atypical agents in acute exacerbations. The secondary aim was to evaluate resistance patterns in the microorganisms.

Methods

The sputum culture of 75 patients admitted to our clinic from January 1, 1999 to December 31, 2002 was evaluated prospectively, for aerobic Gram-positive and Gram-negative bacteria, and serologically for Chlamydophila pneumoniae and Mycoplasma pneumoniae. Sensitivity patterns in potentially pathogenic microorganisms (PPMs) were also investigated.

Results

An infectious agent was identified in 46 patients, either serologically or with sputum culture. Pathogens most commonly demonstrated were: Haemophilus influenzae (30%), Chlamydophila pneumoniae (17%), and Mycoplasma pneumoniae (9%). Mixed infections were diagnosed in 9 patients. PPMs showed a high resistance rate to commonly used antibiotics.

Conclusion

We have shown that microorganisms causing acute exacerbations of COPD are not only typical bacteria (46%) but also atypical pathogens (26%), with unpredictable high rates. Typical agents showed a high resistance to commonly used antibiotics.     

Yield of sputum microbiological examination in patients hospitalized for exacerbations of chronic obstructive pulmonary disease with purulent sputum

BACKGROUND: Whether sputum microbiological examination should be performed systematically in hospitalized patients with chronic obstructive pulmonary disease (COPD) exacerbations remains unclear. OBJECTIVES: To assess the yield of sputum microbiological examination in COPD patients hospitalized in a medical ward for an acute exacerbation with purulent sputum. METHODS: Two hundred consecutive exacerbations in 118 patients were studied. Patients underwent sputum microbiological examination on admission and baseline lung function tests and CT scans were recorded. Factors associated with positive culture were analyzed. RESULTS: Sputum culture was positive (>or=10(7) CFU/ml) in 59% of samples, Haemophilus influenzae and Streptococcus pneumoniae being the most frequent pathogens. Factors associated with positive culture were bronchiectasis, long-term oxygen therapy and low FEV1. Pseudomonas spp. were found in 8.5% of all patients, who all had a FEV1<50% of predicted and were older. Only 25% of sputum samples satisfied all quality criteria. Sputum culture was positive in a high proportion of these samples (80.5%), but also in one half of samples with >25 leukocytes but >10 epithelial cells per field. Microbiological results induced a change in antibiotic therapy in 43.9% of cases with both quality criteria but also in 25.2% of cases with only one quality criterion. Finally, a predominant aspect after Gram stain was found in all positive samples. CONCLUSIONS: These data suggest that sputum microbiological examination with direct examination and leukocyte count should be performed routinely in patients hospitalized for COPD exacerbations with purulent sputum, especially when FEV1 is less than 50% predicted and in patients with bronchiectasis.     

Relation Between Amoxicillin Concentration in Sputum of COPD Patients and Length of Hospitalization

Amoxicillin is a widely used antibiotic in COPD. Little is known about the transfer of amoxicillin into sputum of COPD patients. The objective was to investigate the relationship between the concentration of amoxicillin in sputum in hospitalized COPD patients and length of hospitalization. To be effective against bacterial pathogens, the amoxicillin concentration in target tissues should be higher than the Minimal Inhibiting Concentration (MIC) of 2 mg/l. Therefore, this was also used as the cut-off value for the amoxicillin concentration in sputum, as a marker for lung tissue concentration. Fifty-two COPD in-patients with an exacerbation, treated with amoxicillin clavulanic acid, were included in this cohort study. Of these patients 7 also had pneumonia. Patients were divided in patients with an amoxicillin sputum concentration ≥ 2 mg/l and < 2 mg/l. Furthermore, inflammation markers in sputum and serum and clinical parameters were obtained. Of the 33 patients with usable sputum, 11 had a concentration in sputum ≥ 2 mg/l. The mean length of hospitalization for patients with concentrations below the MIC90 to common respiratory pathogens was 11.0 days, while for patients with concentrations at or above the MIC90 this was 7.0 days (p = 0.005). COPD patients admitted for an acute exacerbation of COPD, with a sputum concentration of amoxicillin ≥ 2 mg/l had a markedly reduced length of hospitalization compared to patients with a concentration < 2 mg/l. It is worthwhile testing whether individualized treatment based on sputum amoxicillin concentrations of patients during hospitalization for acute exacerbations can effectively reduce hospital stay.     

Relation between amoxicillin concentration in sputum of COPD patients and length of hospitalization

Amoxicillin is a widely used antibiotic in COPD. Little is known about the transfer of amoxicillin into sputum of COPD patients. The objective was to investigate the relationship between the concentration of amoxicillin in sputum in hospitalized COPD patients and length of hospitalization. To be effective against bacterial pathogens, the amoxicillin concentration in target tissues should be higher than the Minimal Inhibiting Concentration (MIC) of 2 mg/l. Therefore, this was also used as the cut-off value for the amoxicillin concentration in sputum, as a marker for lung tissue concentration. Fifty-two COPD in-patients with an exacerbation, treated with amoxicillin clavulanic acid, were included in this cohort study. Of these patients 7 also had pneumonia. Patients were divided in patients with an amoxicillin sputum concentration ≥ 2 mg/l and < 2 mg/l. Furthermore, inflammation markers in sputum and serum and clinical parameters were obtained. Of the 33 patients with usable sputum, 11 had a concentration in sputum ≥ 2 mg/l. The mean length of hospitalization for patients with concentrations below the MIC90 to common respiratory pathogens was 11.0 days, while for patients with concentrations at or above the MIC90 this was 7.0 days (p = 0.005). COPD patients admitted for an acute exacerbation of COPD, with a sputum concentration of amoxicillin ≥ 2 mg/l had a markedly reduced length of hospitalization compared to patients with a concentration < 2 mg/l. It is worthwhile testing whether individualized treatment based on sputum amoxicillin concentrations of patients during hospitalization for acute exacerbations can effectively reduce hospital stay.     

COPD稳定期肺功能与急性加重期痰细菌学关系探讨

目的探讨COPD稳定期肺功能分级与急性加重期痰培养细菌学状况以及细菌感染之间关系。方法对我院142例有发病前稳定期肺功能检查结果的AECOPD住院病例进行回顾性分析。结果痰培养阳性者73例,阳性率为51.41%。FEV1占预计值百分比(FEV1%)50%时假单胞菌、肠杆菌及不动杆菌出现的机会比FEV1%≥50%时多,FEV1%50%与假单胞菌、肠杆菌和不动杆菌有高度相关性(P0.05)。结论随着COPD患者基础肺功能的降低,特别在FEV1%50%时,发生急性加重时痰菌以假单胞菌和肠杆菌最常见。FEV1%≥50%时痰培养诊断率较低,大多数无菌生长。     

慢性阻塞性肺疾病患者急性加重期血清降钙素原水平的变化及临床意义

目的探讨慢性阻塞性肺疾病(COPD)患者急性加重期血清降钙素原(PCT)水平的变化及其临床意义。方法2004年10月至2005年3月在我院呼吸科门诊45例COPD急性加重期患者,治疗前采用免疫发光法测定其血清PCT水平,并进行诱导痰细菌定量培养;治疗后达稳定期时再次进行血清PCT水平测定及诱导痰细菌定量培养作为自身对照。以痰中下呼吸道潜在病原菌(PPM)浓度≥107CFU／ml作为诊断COPD急性加重期细菌感染的标准,将COPD急性加重期患者分为有细菌感染组(A组,15例)、无细菌感染组(B组,30例)。结果(1)45例患者在急性加重期时,有21例(46．7％)痰培养出PPM,其中15例痰中PPM浓度≥107CFU／ml。稳定期时有9例患者的病原菌仍存留[2．8×106(1．3×106,1．9×107)CFU／ml],但细菌浓度较急性加重期显著降低[7．0×107 (4．5×107,7．1×108)CFU／ml,Z=-2．666,P=0．008]。(2)在急性加重期,A组血清PCT水平[0．24 (0．17,0．28)μgL]显著高于B组[0．13(0．10,0．18)μg/L,Z=-3．531,P=0．000]。A组患者稳定期血清PCT含量为0．12(0．10,0．14)μg/L,显著低于急性加重期[0．24(0．17,0．28)μg／L,Z= -3．298,P=0．001];B组患者稳定期血清PCT含量为0．13(0．10,0．15)μg/L,与急性加重期[0．13 (0．10,0．18)μg／L]比较,差异无统计学意义(Z=-1．614,P=0．107)。在稳定期2组血清PCT含量比较差异亦无统计学意义(Z=-0．382,P=0．703)。结论COPD急性加重期患者血PCT水平升高可能与细菌感染有关。     

Mortality of COPD Patients Infected with Multi-Resistant Pseudomonas aeruginosa : A Case and Control Study

Abstract Background:   The incidence of infections caused by multiresistant Pseudomonas aeruginosa (MDRP) is increasing, especially in critically ill patients. The relevance of MDRP in the prognosis of chronic obstructive pulmonary disease (COPD) acute exacerbation in patients admitted to the hospital’s general ward is not well known. Patients and Methods:   Case and control study. Cases were patients admitted for COPD acute exacerbation in which a MDRP was isolated from spontaneous sputum. MDRP was defined as the absence of susceptibility to three or more antibiotic families (betalactams, quinolones, carbapenems and aminoglycosides). Patients currently or previously admitted to the intensive care unit (ICU), who had a recent surgery, neoplasia or immunosuppressive treatment were excluded from the study. Patients from the control group were admitted for COPD acute exacerbation and matched 1:1 with each case-patient in terms of age, sex, date of admission and degree of airway obstruction. Pseudomonas aeruginosa susceptible to all antimicrobials or other microorganisms was isolated from sputum. Results:   During the study period (2000–2005), 50 casepatients and 50 controls were included. Crude mortality at 2 years was 60% for the case-patients and 28% for the control group. In the logistic regression analysis adjusted for age, FEV₁ and number of previous hospital admissions, MDRP infection was associated to an increased mortality in comparison to patients without MDRP (OR = 6.2; IC 95%: 1.7–22.1; p < 0.01). Conclusions:   In COPD patients admitted to the general ward, acute exacerbation with MDRP in sputum was associated with higher mortality.     

慢性阻塞性肺疾病患者肺炎衣原体感染的研究

目的 探讨肺炎衣原体感染与慢性阻塞性肺疾病（COPD）的相关性。方法 选择61例COPD急性加重期患者,35例COPD稳定期患者,26名正常对照者,采用微量免疫荧光法测定血清肺炎衣原体特异性抗体IgA,IgM,IgG,套式聚俣酶链反应检测痰中的肺炎衣原体DNA。结果 COPD急性加重期患者的急性肺炎衣原体的感染率为31．1％,明显高于COPD稳定期和且（P＜0．05）。COPD急性加重期组和稳定期组的慢性肺炎衣原体感染率分别为21．3％和31．4％,明显高于对照组（P均＜0．05）,同时IgA的几何平均滴度在COPD急性加重期中最高（20．5）,COPD稳定期组中次之（10．8）,对照组最低（3．6）,三组间差异有显著性（P＜0．05）。结论 急性肺炎衣原体感染为COPD急性加重的一个重要诊因,慢性肺炎衣原体感染可能参与COPD的发病机制。