Chieh-Liang Wu

Effects of Prone Position on Inflammatory Markers in Patients with ARDS Due to Community-acquired Pneumonia

BACKGROUND/PURPOSE Acute respiratory distress syndrome (ARDS) is a serious disorder of intensive care unit patients. We evaluated the safety of continuous prone position ventilation (PRONE) and its effects on oxygenation and plasma cytokine concentrations in patients with ARDS caused by severe community-acquired pneumonia (CAP). METHODS This was a prospective observational clinical study conducted in a respiratory intensive care unit of a 1200-bed medical center in central Taiwan. Twenty-two patients with severe CAP and ARDS were included. They were treated by traditional supine ventilation (SUPINE, n = 11) or PRONE (n = 11) if they met the criteria for ARDS. Patients in the PRONE group were ventilated in prone position continuously for at least 72 hours. Plasma cytokines were collected and analyzed at baseline, 24 hours and 72 hours after enrolment. Serial PaO2/FiO2 and complications were evaluated. RESULTS Complications associated with PRONE were minor and self-limited. PRONE had higher PaO2/FiO2 ratio than SUPINE did at 48 hours after enrolment. The levels of plasma IL-6 concentration declined significantly with time in the PRONE group (p = 0.011). The levels of plasma IL-6 concentration at enrolment, 24 hours and 72 hours after enrolment also predicted the 14th day mortality of all patients. CONCLUSION PRONE was a safe and effective maneuver for improving oxygenation in patients with severe CAP and ARDS. PRONE also influenced IL-6 expression in patients with severe CAP.

Bronchoalveolar interleukin-1β: A marker of bacterial burden in mechanically ventilated patients with community-acquired pneumonia

ObjectiveTo assess the relationship between concentrations of bronchoalveolar cytokines and bacterial burden (quantitative bacterial count) in intubated patients with a presumptive diagnosis of community-acquired pneumonia. DesignA cross-sectional and clinical investigation. SettingMedical/surgical and respiratory intensive care unit of a tertiary 1,200-bed medical center. PatientsAccording to the time course of community-acquired pneumonia at the time of study with bronchoalveolar lavage, 69 mechanically ventilated patients were divided into three subgroups: primary (n = 11), referral (n = 23), and treated (n = 35) community-acquired pneumonia. InterventionsBronchoalveolar lavage was performed in the most abnormal area on chest radiograph by fiberoptic bronchoscope. Bronchoalveolar lavage fluid was processed for quantitative bacterial culture. The concentrations of bronchoalveolar lavage cytokines (tumor necrosis factor-&agr;, interleukin-1&bgr;, interleukin-6, interleukin-8, and interleukin-10) also were measured. Measurements and Main ResultsThirty-two patients had a positive bacterial culture (bronchoalveolar lavage ≥103 colony-forming units/mL). Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, and Klebsiella pneumoniae made up 76% of pathogens recovered at high concentrations. The concentrations of bronchoalveolar lavage interleukin-1&bgr; were 199.1 ± 32.1 and 54.9 ± 13.0 pg/mL (mean ± se) in the patients with positive and negative bacterial culture, respectively (p < .001). Bronchoalveolar lavage interleukin-1&bgr; was significantly higher in the patients with a high bacterial burden (p < .001), with mixed bacterial infection (p < .001), and with P. aeruginosa pneumonia (p < .001), compared with values in patients without these features. The relationship between bacterial load and concentrations of bronchoalveolar lavage interleukin-1&bgr; was very strong in the patients with primary and referral community-acquired pneumonia but was borderline in treated community-acquired pneumonia. ConclusionsThe common pathogens were similar to the core pathogens of hospital-acquired pneumonia, probably due to antibiotic effects, delayed sampling, and superimposed nosocomial infection. Since the concentration of bronchoalveolar lavage interleukin-1&bgr; was correlated with bacterial burden in the alveoli, it may be a marker for progressive and ongoing inflammation in patients who have not responded to pneumonia therapy and who have persistence of bacteria in the lung.

Etiology and cytokine expression in patients requiring mechanical ventilation due to severe community-acquired pneumonia.

BACKGROUND The relationship between bacterial etiology and serum cytokine levels in patients with severe community-acquired pneumonia (CAP) without response to initial empiric treatment remains unclear. This study investigated the bacterial etiology, outcomes, and bronchoalveolar and systemic cytokines (interleukin [IL]-1beta, IL-8, IL-10) in these patients. METHODS This hospital-based study enrolled 47 consecutive patients without response to initial empiric treatment and requiring mechanical ventilation due to severe CAP between July 1, 2000 and October 31, 2001, in a respiratory intensive care unit of a 1200-bed teaching hospital in central Taiwan. Bronchoalveolar lavage (BAL) was performed within 3 days after hospitalization. BAL fluid was processed for quantitative bacterial cultures. Blood samples were taken just before BAL, and the levels of both BAL and serum cytokines were measured. RESULTS The most common pathogens isolated were Pseudomonas aeruginosa (22.5%) and Klebsiella pneumoniae (25%). Patients with a K. pneumoniae isolate (n = 10) had significantly higher levels of IL-1beta in BAL fluid and significantly higher levels of IL-10 in serum and BAL fluid than patients with other etiologies. Non-survivors had higher levels of serum IL-8 (p = 0.001), serum IL-10 (p < 0.001) and BAL IL-10 (p = 0.039) than survivors. Marked increases in local and systemic cytokine expression (IL-8 and IL-10) were noted in rapidly fatal cases. CONCLUSION P. aeruginosa and K. pneumoniae are the most common causes of CAP requiring mechanical ventilation in Taiwan. Cytokine patterns in the BAL fluid and serum of patients with severe CAP due to K. pneumoniae showed significant elevations compared to other pathogens. Bronchoalveolar and systemic cytokine levels (especially IL-10) predicted mortality. These findings suggest the need for a clinical trial to determine how immunomodulating therapy might affect cytokine profiles and clinical outcome.

Predictive value of serial measurements of sTREM-1 in the treatment response of patients with community-acquired pneumonia.

BACKGROUND/PURPOSE To evaluate the roles of plasma sTREM-1 (soluble triggering receptor expressed on myeloid cells-1) and C-reactive protein (CRP) in predicting treatment response in patients with community-acquired pneumonia (CAP). METHODS Patients with CAP were enrolled prospectively at a medical center in central Taiwan from September 1, 2004 to July 31, 2005. They were treated according to the guidelines proposed by the American Thoracic Society. Patients were noted as nonresponsive to initial treatment if they had one of the following: persistent fever for more than 3 days, progression on chest radiograph, switching to other antibiotics, or need of mechanical ventilation and/or chest tube drainage. RESULTS Fifty-eight patients (43 males/15 females; mean age, 67 +/- 21 years) with CAP were enrolled. Twelve (12/58, 21%) were nonresponsive. In the response group, CRP was reduced up to 58% from day 1 to day 3 (from 18.8 to 7.8 mg/dL), whereas sTREM-1 was reduced by only 15% (from 32.8 to 28.1 pg/mL). In the nonresponse group, CRP still declined 20% (from 22.2 to 17.7 mg/dL), whereas sTREM-1 was persistently high (from 61.7 to 63.7 pg/mL). Using multivariate logistic regression analysis, both CRP (p = 0.006) and sTREM-1 (p = 0.046) on day 3 predicted treatment response significantly, but CRP on day 3 had stronger statistic power. CONCLUSION Both CRP and sTREM-1 on day 3 could be useful in predicting nonresponsive CAP patients. Differential trends between sTREM-1 and CRP in nonresponsive CAP suggest that sTREM-1 could be an adjuvant biomarker to CRP in predicting CAP patients without response to empiric treatment.

Features of severe pneumonia in patients with undiagnosed pulmonary tuberculosis in an intensive care unit

BACKGROUND AND PURPOSE Early antituberculosis (anti-TB) therapy in hospitalized, severely ill patients with pulmonary tuberculosis (PTB) diminishes the mortality and morbidity rate and also reduces nosocomial transmission. However, delayed diagnosis of PTB is common in the respiratory intensive care unit (RICU), especially in patients with respiratory failure. This retrospective study evaluated the clinical features of RICU patients with severe pneumonia and undiagnosed active PTB, in order to determine which specific features might help in the screening of these patients. METHODS Patients with severe pneumonia with undiagnosed active PTB and those without active PTB on admission to the RICU, from March 1, 2000 to August 31, 2002, were compared. The 2 groups of patients were matched for age, gender, and Acute Physiology and Chronic Health Evaluation (APACHE) II score prior to the analysis. Data on clinical course, chest radiographic patterns, and laboratory findings were collected. RESULTS Thirty five patients in the case group were matched with 35 controls who were similar with regard to age, gender, smoking history, acute lung injury score, and the presence of underlying disease. The duration of symptoms before admission was significantly longer in the case group than in the control group (15.1 +/- 13.9 vs 7.8 +/- 7.6 days, p = 0.012). The mean interval from admission to the RICU to the initiation of anti-TB therapy was 10.0 +/- 9.8 days. Small nodular lesions (p = 0.044) and cavitary lesions (p = 0.013) predominated on the chest radiograph in the case group. The mortality rates at discharge were not significantly different between the case group and the control group. CONCLUSIONS These data suggest that when a patient developing severe pneumonia has a history of a sub-acute or chronic illness longer than 2 weeks in duration, and predominant small nodular or cavitary patterns on chest radiograph, active PTB should be considered.

Reply to Friedrich et al

©2008 Elsevier & Formosan Medical Association . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Divisions of 1Chest Medicine and 6Critical Care and Respiratory Therapy, Department of Internal Medicine, and 3Department of Nursing, Taichung Veterans General Hospital, 2Central Taiwan University of Science and Technology, 4Department of Medical Technology, Chung Shan Medical University, Taichung, 5Laboratory of Epidemiology and Biostatistics, Taipei Veterans General Hospital, Taipei, and 7Department of Life Sciences, National Chung-Hsing University, Taichung, Taiwan.

Clinical Features of Extended-Spectrum Beta-Lactamase-Producing Organisms Colonized in Patients Prior to Admission to a Respiratory Intensive Care Unit

Background: The prevalence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coil and Klebsiella pneumoniae has increased markedly in recent years. The aim of this study was to determine the risk factors of colonization by ESBL-producing E. coli or K. pneumoniae and their association with the patients location prior to admission. Methods: The study was conducted over a 5-month period in a respiratory intensive care unit. All patients were enrolled with their consent. A rectal swab was done within 48 hours of admission, and a double-disc diffusion test was used to detect the ESBL-producing organisms. The medical records of those patients were reviewed retrospectively. Results: In all, 260 cases were enrolled. Twenty-eight of the patients revealed ESBL-producing E. coil or K. pneumoniae colonization in the feces. According to their location for 48 hours before admission, we divided the patients into 3 groups: community (n=93), local hospital (n=92), and medical center (n=75). The incidence of fecal colonization of ESBL-producing organisms was 6%, 14%, 8% in each group. However, the clinical features between the ESBL and non-ESBL patients were similar in our series. Conclusions: Fecal colonization of ESBL-producing organisms was common in patients on admission to the respiratory intensive care unit, especially those from the local hospital. There were no clinical characteristics to predict colonization on admission, so a cohort barrier observation should be considered in the RICU to prevent the nosocomial spread of ESBL-producing E. coil or K. pneumoniae infections.

Virulent Gram-Negative Bacilli Isolated in Sputum Culture Predict Length of Hospital Stay in Patients with Community-Acquired Pneumonia

Background: The role of sputum culture in identifying infectious pathogens and in guiding initial empiric antibiotic treatment for community-acquired pneumonia (CAP) is limited. However, sputum culture is still widely used clinically in Taiwan. The aim of this retrospective study was to examine the value of sputum culture in terms of the clinical outcome. Methods and patients: From January 1, 2002 to December 31, 2002, CAP patients who were admitted to our hospital and had a sputum culture on admission day were enrolled. Patients were divided into 2 groups: one, a Gram-negative bacilli (GNB) group, for those with a presence of Klebsiella pneumoniae and/or Pseudomonas aeruginosa, and the other, a non-GNB group. Both groups were stratified by means of the modified Fines pneumonia severity index into low-and high-risk patients. We determined the impact of virulent GNB isolated in the sputum culture on in-hospital mortality and length of stay (LOS) in the hospital. Results: One hundred and forty-eight patients were enrolled. Thirty-eight patients (25.7%) were in the virulent GNB group. The demographic characteristics were similar in both groups. In terms of in-hospital mortality, there was no significant difference between the 2 groups. LOS was significantly longer in the virulent group (18.89±14.85 vs. 12.74±11.35 days; P=0.024), especially for high-risk patients (27.24±15.67 vs. 17.50±13.07 days; P=0.019). The possible explanation for this is that more patients were admitted to the ICU. Conclusion: We conclude that virulent GNB isolated in sputum culture, especially in a high- risk patient group, could result in a significant increase in LOS in the hospital.

Impact of Initial Antibiotic Choice on Clinical Outcomes of Community-Acquired Pneumonia in Adults

Background: Adequate and immediate empiric antibiotic treatment improves the outcome of community-acquired pneumonia (CAP). Using the antibiotic regulation guidelines of the Bureau of National Health Insurance, we examined the impact of initial antibiotic choice on the outcome of CAP. Methods and patients: In this study, we retrospectively reviewed patients with CAP (modified Fine risk classes II, Ill and IV) who were hospitalized in Taichung Veterans General Hospital in 2002. We assessed the outcome parameters, including total hospital costs, length of hospital stay (LOS), and in-hospital survival rate. We compared the outcome parameters of 2 groups: the line antibiotics (1(superscript st) ATB) group and the 2(superscript nd) line antibiotics (2(superscript nd) ATB) group. Results: A total of 116 patients were enrolled in the study. Compared to the 1(superscript st) ATB group, the 2(superscript nd) ATB group had a longer length of stay (Mann-Whitney U test, p=0.008) and higher hospital costs (Mann-Whitney U test, p=0.0004), but no significant difference in survival rate (log-rank test, p=0.662). Conclusion: The 2(superscript nd) ATB group did not demonstrate a better outcome. This was probably due to the difference in disease severity.

Acute Respiratory Distress Syndrome due to Chlamydia pneumoniae Infection In A Healthy Young Adult: A Case Report and Literature Review

Chlamydia pneumoniae is one of the common pathogens in community-acquired pneumonia (CAP). The clinical presentation is usually mild or even unrecognized. Severe CAP due to C. pneumoniae is usually found in the elderly or in patients with underlying diseases. Herein, we report a previously healthy young adult, who developed severe CAP with rapid progression to acute respiratory distress syndrome (ARDS) due to C. pneumoniae infection. With aggressive treatment, the patient recovered well without residual pulmonary function impairment. If a patient presents with ARDS without a clear-cut etiology, C. pneumoniae infection should be included in the differential diagnosis, even in the healthy young adult.