Ana Rañó

Bacterial colonisation in patients with bronchiectasis: microbiological pattern and risk factors

Background: A study was undertaken to investigate the incidence, diagnostic yield of non-invasive and bronchoscopic techniques, and risk factors of airway colonisation in patients with bronchiectasis in a stable clinical situation. Methods: A 2 year prospective study of 77 patients with bronchiectasis in a stable clinical condition was performed in an 800 bed tertiary university hospital. The interventions used were pharyngeal swabs, sputum cultures and quantitative protected specimen brush (PSB) bacterial cultures (cut off point ≥102 cfu/ml) and bronchoalveolar lavage (BAL) (cut off point ≥103 cfu/ml). Results: The incidence of bronchial colonisation with potential pathogenic microorganisms (PPMs) was 64%. The most frequent PPMs isolated were Haemophilus influenzae (55%) and Pseudomonas spp (26%). Resistance to antibiotics was found in 30% of the isolated pathogens. When the sample was appropriate, the operative characteristics of the sputum cultures were similar to those obtained with the PSB taken as a gold standard. Risk factors associated with bronchial colonisation by PPMs in the multivariate analysis were: (1) diagnosis of bronchiectasis before the age of 14 years (odds ratio (OR)=3.92, 95% CI 1.29 to 11.95), (2) forced expiratory volume in 1 second (FEV1) <80% predicted (OR=3.91, 95% CI 1.30 to 11.78), and (3) presence of varicose or cystic bronchiectasis (OR=4.80, 95% CI 1.11 to 21.46). Conclusions: Clinically stable patients with bronchiectasis have a high prevalence of bronchial colonisation by PPMs. Sputum culture is a good alternative to bronchoscopic procedures for evaluation of this colonisation. Early diagnosis of bronchiectasis, presence of varicose-cystic bronchiectasis, and FEV1 <80% predicted appear to be risk factors for bronchial colonisation with PPMs.

Pulmonary infiltrates in HIV-infected patients in the highly active antiretroviral therapy era in Spain

Objective: To study the incidence, etiology, and outcome of pulmonary infiltrates (PIs) in HIV‐infected patients and to evaluate the yield of diagnostic procedures. Design: Prospective observational study of consecutive hospital admissions. Setting: Tertiary hospital. Patients: HIV‐infected patients with new‐onset radiologic PIs from April 1998 to March 1999. Methods: The study protocol included chest radiography, blood and sputum cultures, serologic testing for “atypical” causes of pneumonia, testing for Legionella urinary antigen, testing for cytomegalovirus antigenemia, and bronchoscopy in case of diffuse or progressive PIs. Results: One hundred two episodes in 92 patients were recorded. The incidence of PIs was 18 episodes per 100 hospital admission‐years (95% confidence interval [CI]: 15‐21). An etiologic diagnosis was achieved in 62 cases (61%). Bacterial pneumonia (BP), Pneumocystis carinii pneumonia (PCP), and mycobacteriosis were the main diagnoses. The incidences of BP and mycobacteriosis were not statistically different in highly active antiretroviral therapy (HAART) versus non‐HAART patients. The incidence of PCP was lower in those receiving HAART (p = .011), however. Nine patients died (10%). Independent factors associated with higher mortality were mechanical ventilation (odds ratio [OR] = 83; CI: 4.2‐1,682), age >50 years (OR = 23; CI: 2‐283), and not having an etiologic diagnosis (OR = 22; CI: 1.6‐293). Conclusions: Pulmonary infiltrates are still a frequent cause of hospital admission in the HAART era, and BP is the main etiology. There was no difference in the rate of BP and mycobacteriosis in HAART and non‐HAART patients. Not having an etiologic diagnosis is an independent factor associated with mortality.

Pulmonary Infiltrates in Immunosuppressed Patients: Analysis of a Diagnostic Protocol

ABSTRACT A diagnostic protocol was started to study the etiology of pulmonary infiltrates in immunosuppressed patients. The diagnostic yields of the different techniques were analyzed, with special emphasis on the importance of the sample quality and the role of rapid techniques in the diagnostic strategy. In total, 241 patients with newly developed pulmonary infiltrates within a period of 19 months were included. Noninvasive or invasive evaluation was performed according to the characteristics of the infiltrates. Diagnosis was achieved in 202 patients (84%); 173 patients (72%) had pneumonia, and specific etiologic agents were found in 114 (66%). Bronchoaspirate and bronchoalveolar lavage showed the highest yields, either on global analysis (23 of 35 specimens [66%] and 70 of 134 specimens [52%], respectively) or on analysis of each type of pneumonia. A tendency toward better results with optimal-quality samples was observed, and a statistically significant difference was found in sputum bacterial culture. Rapid diagnostic tests yielded results in 71 of 114 (62.2%) diagnoses of etiological pneumonia.

Factors associated with unknown aetiology in patients with community-acquired pneumonia

Despite comprehensive diagnostic work-up, the aetiology of community-acquired pneumonia (CAP) remains undetermined in 30–60% of cases. The authors studied factors associated with undiagnosed pneumonia. Patients hospitalised with CAP and being evaluated by two blood cultures, at least one valid lower respiratory tract sample, and serology on admission were prospectively recorded. Patients who had received antimicrobial pretreatment were excluded. Patients with definite or probable aetiology were compared to those with undetermined aetiology by uni- and multivariable analysis. A total 204 patients were eligible for the study. The aetiology remained undetermined in 82 (40%) patients, whereas a definite aetiology could be established in 89 (44%) and a probable one in 33 (16%). In multivariable analysis, factors associated with undetermined aetiology included age >70 yrs, renal and cardiac comorbidity, and nonalveolar infiltrates on the chest radiograph. There was no association of undiagnosed pneumonia with mortality. Age and host factors were associated with unknown aetiology of community-acquired pneumonia. Some of these cases may also represent fluid volume overload mimicking pneumonia.

Respiratory infectious complications in the intensive care unit.

Ventilator-associated pneumonia is the most common infectious respiratory complication in intensive care unit patients, particularly those needing mechanical ventilation. Ventilator-associated pneumonia represents a challenging problem in terms of diagnosis, treatment, and prevention. Nosocomial sinusitis is another respiratory infection, not uncommon in mechanically ventilated patients. This type of infection has to be suspected in nasally intubated patients and may be a hidden focus of fever and sepsis.

Inflammatory Responses in Blood Samples of Human Immunodeficiency Virus-Infected Patients with Pulmonary Infections

ABSTRACT We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1β (IL-1β), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-α) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-α, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1β, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-α levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5).

Inflammatory response associated with pulmonary complications in non-HIV immunocompromised patients

Background: A study was undertaken to evaluate the local and systemic inflammatory response associated with pulmonary complications in immunocompromised patients and potential implications regarding severity and prognosis. Methods: Levels of different inflammatory mediators were measured in the bronchoalveolar lavage (BAL) fluid and serum on days 1 and 4 after the identification of the pulmonary complication in 127 patients with different immunosuppressive conditions. Results: Pulmonary complications were characterised by a high percentage of neutrophils and increased levels of tumour necrosis factor (TNF)-α, interleukin (IL)-6, IL-8 and IL-10 in the BAL fluid and high serum levels of TNF-α, IL-6, and plasma C-reactive protein (CRP). The inflammatory response was similar in the different groups of immunocompromised patients evaluated. The levels of proinflammatory cytokines were higher in patients with pulmonary infections, particularly those of bacterial aetiology. Patients with a more severe pulmonary infection had a more intense local and systemic inflammatory response. A BAL fluid IL-6 level of >40 pg/ml was an independent predictor of mortality (OR 4.65, 95% CI 1.3 to 16.1), together with a need for mechanical ventilation (OR 13.5, 95% CI 3.2 to 57.3). Patients who died had persistently high levels of CRP on day 4. Conclusions: The evaluation of the inflammatory response, particularly the determination of IL-6 levels in the BAL fluid and CRP in the serum, may be useful for deciding the appropriate management of pulmonary complications in immunocompromised patients.

Pulmonary infections in non-HIV-immunocompromised patients

Purpose of review Pulmonary infections are the most frequent complications in non-HIV-immunocompromised patients and portend a high mortality. This scenario represents a challenging task for clinicians and an important subject of clinical research from different perspectives. This review comments on the results of relevant original articles in this area published from 2003 to the present. Recent findings The present review addresses the etiology of the pulmonary infiltrates in immunocompromised patients, the use of new emerging diagnostic tools and medical devices in the clinical management of these infiltrates, and the greater understanding of the inflammatory immune response associated with infection in this setting. Summary Advances in diagnostic tests and therapeutic devices are facilitating the clinical management of pulmonary infections. New challenges are emerging, however, such as the growing evidence regarding the important role of respiratory viruses as a common cause of lower respiratory tract infections. Finally, new insights into the mechanisms of the inflammatory response associated with pulmonary complications can help understanding their pathogenesis, improve prevention and diagnosis, and anticipate future therapeutic modalities.

Associated inflammatory response in pneumonia: role of adjunctive therapy with glucocorticoids

Purpose of review This article reviews the potential use of glucocorticoids as adjunctive therapy in the management of patients with severe bacterial pneumonia or pulmonary infections of other etiologies. Recent findings The importance of an adequate assessment of the inflammatory process and the appearance of inflammatory markers that correlate with the severity of pneumonia is underlined. A recent randomized clinical trial indicates that adjunctive treatment of severe community-acquired pneumonia with glucocorticoids reduces complications and improves survival. The role of glucocorticoids in other lung infections is also reviewed. The design of new compounds with similar anti-inflammatory properties to classical glucocorticoids but with significantly fewer side effects constitutes a specific challenge for the near future. Summary Although adjunctive treatment with glucocorticoids in severe pneumonia is probably indicated, further randomized clinical trials are urgently needed to confirm the preliminary positive results. In this regard, a proper evaluation of the inflammatory response is likely to be essential for the accurate selection of the target population.

Nosocomial pneumonia in immunosuppressed patients

Nosocomial pneumonia represents a serious challenge for clinicians caring for IC patients. Although there have been advances in prophylactic, preemptive, and therapeutic measures, the implications of an inadequate empirical treatment for survival require a prompt and active attitude. A great diversity of diagnostic and laboratory procedures is currently available. In each case, the clinician must determine the tests that should be performed based on different variables. The proper use of noninvasive and bronchoscopic procedures substantially increases the diagnostic yield causing changes in the empirical treatment in most patients. The authors believe that fiberoptic bronchoscopy must be done early when the pulmonary infiltrates are identified if there is not a rapid (48 hours) and clear response to empiric treatment. This approach allows the establishment of a more specific treatment when the possibilities of full recovery are still high. The potential benefit of treatment modifications for survival in IC patients who require MV and undergo bronchoscopy is most probably minimal, because of the severity and irreversibility of the underlying pulmonary process. It is hoped that the application of molecular tools in diagnosis and the advances in preventive strategies and therapeutic agents will improve the survival of NP in a population of IC patients that is expected to grow over the next years.