Rosario Menéndez

Risk factors of treatment failure in community acquired pneumonia: implications for disease outcome

Background: An inadequate response to initial empirical treatment of community acquired pneumonia (CAP) represents a challenge for clinicians and requires early identification and intervention. A study was undertaken to quantify the incidence of failure of empirical treatment in CAP, to identify risk factors for treatment failure, and to determine the implications of treatment failure on the outcome. Methods: A prospective multicentre cohort study was performed in 1424 hospitalised patients from 15 hospitals. Early treatment failure (<72 hours), late treatment failure, and in-hospital mortality were recorded. Results: Treatment failure occurred in 215 patients (15.1%): 134 early failure (62.3%) and 81 late failure (37.7%). The causes were infectious in 86 patients (40%), non-infectious in 34 (15.8%), and undetermined in 95. The independent risk factors associated with treatment failure in a stepwise logistic regression analysis were liver disease, pneumonia risk class, leucopenia, multilobar CAP, pleural effusion, and radiological signs of cavitation. Independent factors associated with a lower risk of treatment failure were influenza vaccination, initial treatment with fluoroquinolones, and chronic obstructive pulmonary disease (COPD). Mortality was significantly higher in patients with treatment failure (25% v 2%). Failure of empirical treatment increased the mortality of CAP 11-fold after adjustment for risk class. Conclusions: Although these findings need to be confirmed by randomised studies, they suggest possible interventions to decrease mortality due to CAP.

Biomarkers improve mortality prediction by prognostic scales in community-acquired pneumonia

Background: Prognostic scales provide a useful tool to predict mortality in community-acquired pneumonia (CAP). However, the inflammatory response of the host, crucial in resolution and outcome, is not included in the prognostic scales. Methods: The aim of this study was to investigate whether information about the initial inflammatory cytokine profile and markers increases the accuracy of prognostic scales to predict 30-day mortality. To this aim, a prospective cohort study in two tertiary care hospitals was designed. Procalcitonin (PCT), C-reactive protein (CRP) and the systemic cytokines tumour necrosis factor α (TNFα) and interleukins IL6, IL8 and IL10 were measured at admission. Initial severity was assessed by PSI (Pneumonia Severity Index), CURB65 (Confusion, Urea nitrogen, Respiratory rate, Blood pressure, ≥65 years of age) and CRB65 (Confusion, Respiratory rate, Blood pressure, ≥65 years of age) scales. A total of 453 hospitalised CAP patients were included. Results: The 36 patients who died (7.8%) had significantly increased levels of IL6, IL8, PCT and CRP. In regression logistic analyses, high levels of CRP and IL6 showed an independent predictive value for predicting 30-day mortality, after adjustment for prognostic scales. Adding CRP to PSI significantly increased the area under the receiver operating characteristic curve (AUC) from 0.80 to 0.85, that of CURB65 from 0.82 to 0.85 and that of CRB65 from 0.79 to 0.85. Adding IL6 or PCT values to CRP did not significantly increase the AUC of any scale. When using two scales (PSI and CURB65/CRB65) and CRP simultaneously the AUC was 0.88. Conclusions: Adding CRP levels to PSI, CURB65 and CRB65 scales improves the 30-day mortality prediction. The highest predictive value is reached with a combination of two scales and CRP. Further validation of that improvement is needed.

Effect of corticosteroids on treatment failure among hospitalized patients with severe community-acquired pneumonia and high inflammatory response: a randomized clinical trial.

IMPORTANCE In patients with severe community-acquired pneumonia, treatment failure is associated with excessive inflammatory response and worse outcomes. Corticosteroids may modulate cytokine release in these patients, but the benefit of this adjunctive therapy remains controversial. OBJECTIVE To assess the effect of corticosteroids in patients with severe community-acquired pneumonia and high associated inflammatory response. DESIGN, SETTING, AND PARTICIPANTS Multicenter, randomized, double-blind, placebo-controlled trial conducted in 3 Spanish teaching hospitals involving patients with both severe community-acquired pneumonia and a high inflammatory response, which was defined as a level of C-reactive protein greater than 150 mg/L at admission. Patients were recruited and followed up from June 2004 through February 2012. INTERVENTIONS Patients were randomized to receive either an intravenous bolus of 0.5 mg/kg per 12 hours of methylprednisolone (n = 61) or placebo (n = 59) for 5 days started within 36 hours of hospital admission. MAIN OUTCOMES AND MEASURES The primary outcome was treatment failure (composite outcome of early treatment failure defined as [1] clinical deterioration indicated by development of shock, [2] need for invasive mechanical ventilation not present at baseline, or [3] death within 72 hours of treatment; or composite outcome of late treatment failure defined as [1] radiographic progression, [2] persistence of severe respiratory failure, [3] development of shock, [4] need for invasive mechanical ventilation not present at baseline, or [5] death between 72 hours and 120 hours after treatment initiation; or both early and late treatment failure). In-hospital mortality was a secondary outcome and adverse events were assessed. RESULTS There was less treatment failure among patients from the methylprednisolone group (8 patients [13%]) compared with the placebo group (18 patients [31%]) (P = .02), with a difference between groups of 18% (95% CI, 3% to 32%). Corticosteroid treatment reduced the risk of treatment failure (odds ratio, 0.34 [95% CI, 0.14 to 0.87]; P = .02). In-hospital mortality did not differ between the 2 groups (6 patients [10%] in the methylprednisolone group vs 9 patients [15%] in the placebo group; P = .37); the difference between groups was 5% (95% CI, -6% to 17%). Hyperglycemia occurred in 11 patients (18%) in the methylprednisolone group and in 7 patients (12%) in the placebo group (P = .34). CONCLUSIONS AND RELEVANCE Among patients with severe community-acquired pneumonia and high initial inflammatory response, the acute use of methylprednisolone compared with placebo decreased treatment failure. If replicated, these findings would support the use of corticosteroids as adjunctive treatment in this clinical population. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00908713.

Markers of treatment failure in hospitalised community acquired pneumonia

Background: Lack of response to treatment in community acquired pneumonia (CAP) worsens outcome. We evaluated the systemic cytokine profile (tumour necrosis factor α, interleukin (IL)1, IL6, IL8 and IL10), C reactive protein (CRP) and procalcitonin (PCT) in patients with CAP who had treatment failure. Methods: A prospective study was performed in hospitalised patients with CAP. Cytokines, PCT and CRP measurements were obtained on day 1 and after 72 h of treatment. Treatment failure was the endpoint evaluated, with separation of those with early (⩽72 h) or late failure. Results: 453 patients were included: 84 (18%) had treatment failure, of whom 38 (8%) were early failures. Median levels of IL6, PCT and CRP on days 1 and 3 and median levels of IL8 on day 1 were significantly higher in patients with any treatment failure. Logistic regression analysis demonstrated that values above the cut-off points for IL6 (⩾169 pg/ml), IL8 (⩾14 pg/ml) and CRP (⩾21.9 mg/dl) on day 1 had independent predictive value for any treatment failure after adjustment for initial severity; relative risks (OR) found were 1.9, 2.2 and 2.6, respectively. Increased levels for CRP and PCT on day 1 were also independent predictors for early failure. Increased levels for IL6 and CRP were the best predictors of late failure. Conclusions: Serum levels of CRP, IL6 and PCT on days 1 and 3 were independently associated with a higher risk of any treatment failure. Low levels of PCT and CRP on day 1 had a high negative predictive value for early failure.

Severe Community-Acquired Pneumonia: Validation of the Infectious Diseases Society of America/American Thoracic Society Guidelines to Predict an Intensive Care Unit Admission

BACKGROUND The recent Infectious Disease Society of America/American Thoracic Society guidelines for the management of community-acquired pneumonia (CAP) in adults defined a predictive rule to identify patients with severe CAP to determine the need for intensive care unit (ICU) admission. We clinically validated this rule. METHODS We analyzed 2102 episodes of CAP in consecutively hospitalized patients over a 7-year period. The predictive rule consists of at least 1 of 2 major severity criteria (septic shock and invasive mechanical ventilation) or at least 3 of 9 minor severity criteria. We assessed the association of the predictive rule with ICU admission and mortality. RESULTS A total of 235 episodes of CAP (11%) occurred in patients who were admitted to the ICU, whereas the predictive rule identified 397 (19%) of 2102 episodes as severe CAP. The predictive rule and the decision for ICU admission agreed in 1804 (86%) of the episodes (kappa coefficient, 0.45), with a sensitivity of 71% and a specificity of 88%, similar to the 2001 American Thoracic Society guidelines (sensitivity, 66%; specificity, 90%) in predicting ICU admission. Severe CAP criteria had higher sensitivity (58% vs. 46%) and similar specificity (88% vs. 90%), compared with the 2001 American Thoracic Society guidelines in predicting hospital mortality. Invasive mechanical ventilation was the main determinant for ICU admission, followed by septic shock. In the absence of major criteria, ICU admission was not related to survival of patients with minor severity criteria. CONCLUSIONS The predictive rule to identify severe CAP is accurate for ICU admission and improved the prediction of mortality, compared with the previous American Thoracic Society guidelines. The need for ICU admission derived from minor severity criteria alone is uncertain and deserves further investigation.

Reaching Stability in Community-Acquired Pneumonia: The Effects of the Severity of Disease, Treatment, and the Characteristics of Patients

BACKGROUND The natural history of the resolution of infectious parameters in patients with community-acquired pneumonia (CAP) is not completely known. The aim of our study was to identify those factors related to host characteristics, the severity of pneumonia, and treatment that influence clinical stability. METHODS In a prospective, multicenter, observational study, we observed 1424 patients with CAP who were admitted to 15 Spanish hospitals. The main outcome variable was the number of days needed to reach clinical stability (defined as a temperature of <or=37.2 degrees C, a heart rate of <or=100 beats/min, a respiratory rate of <or=24 breaths/min, systolic blood pressure of >or=90 mm Hg, and oxygen saturation >or=90% or arterial oxygen partial pressure of >or=60 mm Hg). RESULTS The median time to stability was 4 days. A Cox proportional hazard model identified 6 independent variables recorded during the first 24 h after hospital admission related to the time needed to reach stability: dyspnea (hazard ratio [HR], 0.76), confusion (HR, 0.66), pleural effusion (HR, 0.67), multilobed CAP (HR, 0.72), high pneumonia severity index (HR, 0.73), and adherence to the Spanish guidelines for treatment of CAP (HR, 1.22). A second Cox model was performed that included complications and response to treatment. This model identified the following 10 independent variables: chronic bronchitis (HR, 0.81), dyspnea (HR, 0.79), confusion (HR, 0.61), multilobed CAP (HR, 0.84), initial severity of disease (HR, 0.73), treatment failure (HR, 0.31), cardiac complications (HR, 0.66), respiratory complications (HR, 0.77), empyema (HR, 0.57), and admission to the intensive care unit (HR, 0.57). CONCLUSIONS Some characteristics of CAP are useful at the time of hospital admission to identify patients who will need a longer hospital stay to reach clinical stability. Empirical treatment that follows guidelines is associated with earlier clinical stability. Complications and treatment failure delay clinical stability.

Community-acquired pneumonia in the elderly: Spanish multicentre study

Community-acquired pneumonia (CAP) in the elderly has increased as a consequence of an overall increase of the elderly population. A controversy about the aetiology and outcome of CAP in this population still exists and more epidemiological studies are needed. A prospective, 12-month, multicentre study was carried out to assess the clinical characteristics, aetiology, evolution and prognostic factors of elderly patients (≥65 yrs) admitted to hospital for CAP. The study included 503 patients (age 76±7 yrs). The clinical picture lasted ≤5 days in 318 (63%) and the main clinical features were cough (n=407, 81%) and fever (n=380, 76%). Aetiological diagnosis was achieved in 199 (40%) cases, with a definite diagnosis obtained in 164 (33%). Of the 223 microorganisms isolated the main agents found were Streptococcus pneumoniae in 98 (49%) and Haemophilus influenzae in 27 (14%). A total of 53 patients died (11%) and the multivariate analysis showed the following factors of bad prognosis: previous bed confinement, alteration in mental status, absence of chills, plasma creatinine ≥1.4 mg·dL−1, oxygen tension in arterial blood/inspiratory oxygen fraction ratio <200 at the time of admission, and shock and renal failure during the evolution. The results of this study may aid in the management of empiric antibiotic treatment in elderly patients with community-acquired pneumonia and the patients who have a greater probability of bad evolution may be identified based on the risk factors.

Implications of endotracheal tube biofilm in ventilator-associated pneumonia response: a state of concept

IntroductionBiofilm in endotracheal tubes (ETT) of ventilated patients has been suggested to play a role in the development of ventilator-associated pneumonia (VAP). Our purpose was to analyze the formation of ETT biofilm and its implication in the response and relapse of VAP.MethodsWe performed a prospective, observational study in a medical intensive care unit. Patients mechanically ventilated for more than 24 hours were consecutively included. We obtained surveillance endotracheal aspirates (ETA) twice weekly and, at extubation, ETTs were processed for microbiological assessment and scanning electron microscopy.ResultsEighty-seven percent of the patients were colonized based on ETA cultures. Biofilm was found in 95% of the ETTs. In 56% of the cases, the same microorganism grew in ETA and biofilm. In both samples the most frequent bacteria isolated were Acinetobacter baumannii and Pseudomonas aeruginosa. Nineteen percent of the patients developed VAP (N = 14), and etiology was predicted by ETA in 100% of the cases. Despite appropriate antibiotic treatment, bacteria involved in VAP were found in biofilm (50%). In this situation, microbial persistence and impaired response to treatment (treatment failure and relapse) were more frequent (100% vs 29%, P = 0.021; 57% vs 14%, P = 0.133).ConclusionsAirway bacterial colonization and biofilm formation on ETTs are early and frequent events in ventilated patients. There is microbiological continuity between airway colonization, biofilm formation and VAP development. Biofilm stands as a pathogenic mechanism for microbial persistence, and impaired response to treatment in VAP.

Prospective Comparison of Severity Scores for Predicting Clinically Relevant Outcomes for Patients Hospitalized With Community-Acquired Pneumonia

BACKGROUND The comparative accuracy and discriminatory power of three validated rules for predicting clinically relevant outcomes other than mortality in patients hospitalized with community-acquired pneumonia (CAP) are unknown. METHODS We prospectively compared the newly developed severe community-acquired pneumonia (SCAP) score, pneumonia severity index (PSI), and the British Thoracic Society confusion, urea > 7 mmol/L, respiratory rate > or = 30 breaths/min, BP < 90 mm Hg systolic or < 60 mm Hg diastolic, age > or = 65 years (CURB-65) rule in an internal validation cohort of 1,189 consecutive adult inpatients with CAP from one hospital and an external validation cohort of 671 consecutive adult inpatients from three other hospitals. Major adverse outcomes were admission to ICU, need for mechanical ventilation, progression to severe sepsis, or treatment failure. Mean hospital length of stay (LOS) was also evaluated. The rules were compared based on sensitivity, specificity, and area under the curve (AUC) of the receiver operating characteristic. RESULTS The rate of all adverse outcomes and hospital LOS increased directly with increasing SCAP, PSI, or CURB-65 scores (p < 0.001) in both cohorts. Patients classified as high risk by the SCAP score showed higher rates of adverse outcomes (ICU admission, 35.8%; mechanical ventilation, 16.4%; severe sepsis, 98.5%; treatment failure, 22.4%) than PSI and CURB-65 high-risk classes. The discriminatory power of SCAP, as measured by AUC, was 0.75 for ICU admission, 0.76 for mechanical ventilation, 0.79 for severe sepsis, and 0.61 for treatment failure in the external validation cohort. AUC differences with PSI or CURB-65 were found. CONCLUSIONS The SCAP score is as accurate or better than other current scoring systems in predicting adverse outcomes in patients hospitalized with CAP while helping classify patients into different categories of increasing risk for potentially closer monitoring.

Sequential measurements of procalcitonin levels in diagnosing ventilator-associated pneumonia

The utility of procalcitonin levels to improve the accuracy of clinical and microbiological parameters in diagnosing ventilator-associated pneumonia (VAP) was evaluated. Sequential measurement of procalcitonin and C-reactive protein levels and the calculation of the simplified Clinical Pulmonary Infection Scores (CPIS) were performed in 44 patients mechanically-ventilated for >48 h with neither active infection for the duration or suspicion of VAP. Patients who developed extrapulmonary infection were excluded. In total, 20 cases were suspected of having VAP and diagnosis was microbiologically confirmed in nine. In patients with confirmed VAP, procalcitonin levels were higher than in those without VAP. C-reactive protein levels and CPIS were lower in patients without suspected VAP, but could not discriminate confirmed and nonconfirmed suspicion of VAP. The best sensitivity and specificity (78 and 97%, respectively) corresponded to procalcitonin. The CPIS resulted in the same sensitivity, but had a lower specificity (80%). C-reactive protein had the worst sensitivity (56%), but a good specificity (91%). A CPIS ≥6 combined with serum levels of procalcitonin ≥2.99 ng·mL−1 did not improve the sensitivity (67%), but resulted in 100% specificity. Procalcitonin might be useful in the diagnosis of ventilator-associated pneumonia. Combined values of Clinical Pulmonary Infection Scores and procalcitonin below the cut-off points excluded false-positive diagnoses of ventilator-associated pneumonia.