Letizia Corinna Morlacchi

Understanding the roles of cytokines and neutrophil activity and neutrophil apoptosis in the protective versus deleterious inflammatory response in pneumonia

Inflammation is a double-edged sword in the outcome of pneumonia. On the one hand, an effective and timely inflammatory response is required to eliminate the invading respiratory pathogen. On the other, a toxic and prolonged inflammatory response may result in lung injury and poor outcomes, even in those receiving advanced medical care. This review focuses on recent understanding of the dynamics of the cytokine response, neutrophil activity, and responsiveness to cytokines and neutrophil lifespan as major elements of lung inflammation resulting in favorable or poor outcomes in lung infection primarily due to pneumococcus and influenza virus. Although some progress has been made in our understanding of the molecular mechanisms of the pneumonia inflammation axis composed of cytokines modulating neutrophil activation and neutrophil apoptosis, important questions remain to be answered. The degree of neutrophil activation, generation of reactive oxygen species, and the release of granule antimicrobial peptides play a key role in microbial pathogen clearance; however, prolonged neutrophil activation may contribute to lung injury and poor outcomes in pneumonia. Molecular markers of the mechanisms regulating neutrophil survival and apoptosis may help in the identification of novel therapeutic targets to modulate inflammation by inducing timely neutrophil apoptosis. A major task is to identify the mechanisms of dysregulation in inflammation leading to toxic responses, thereby targeting a biomarker and enabling timely therapies to modulate inflammation.

Criteria for clinical stability in hospitalised patients with community-acquired pneumonia

The American Thoracic Society (ATS) and Infectious Diseases Society of America (IDSA) suggested two sets of criteria in 2001 and 2007 to define clinical stability in community-acquired pneumonia (CAP). The present study aimed to evaluate the level of agreement between these two sets of criteria and how well they can predict clinical outcomes. A retrospective cohort study was carried out of 487 consecutive patients hospitalised with CAP. Level of agreement was tested using a survival curve analysis, while prediction of outcomes at 30-day follow-up was evaluated through receiver operating characteristic (ROC) analysis. A discrepancy between ATS 2001 and ATS/IDSA 2007 criteria in identifying clinical stability was detected in 62% of the patients. The median (interquartile range) time to clinical stability was 2 (1–4) days based on ATS 2001 and 3 (2–5) days based on ATS/IDSA 2007 criteria (p = 0.012). The daily distribution of patients who reached clinical stability evaluated with both sets was different (p = 0.002). The ROC analysis showed an area under the curve of 0.705 for the ATS 2001 criteria and 0.714 for ATS/IDSA 2007 criteria (p = 0.645). ATS 2001 and ATS/IDSA 2007 criteria for clinical stability in hospitalised patients with CAP are clinically equivalent and both can be used in clinical practice as well as in clinical research. ATS 2001 and ATS/IDSA 2007 criteria for clinical stability in hospitalised patients with CAP are clinically equivalent http://ow.ly/lAeKE

Contrasting Inflammatory Responses in Severe and Non-severe Community-acquired Pneumonia

The objective of this study was to compare systemic and local cytokine profiles and neutrophil responses in patients with severe versus non-severe community-acquired pneumonia (CAP). Hospitalized patients with CAP were grouped according to the pneumonia severity index (PSI), as non-severe (PSI < 91 points) or severe (PSI ≥ 91 points). Blood and sputum samples were collected upon admission. Compared to non-severe CAP patients, the severe CAP group showed higher plasma levels of pro- and anti-inflammatory cytokines but in contrast, lower sputum concentrations of pro-inflammatory cytokines. Blood neutrophil functional responses were elevated in CAP patients compared to healthy controls. However, neutrophils from severe CAP patients showed reduced respiratory burst activity compared to the non-severe group. Results indicate that patients with severe CAP fail to mount a robust local pro-inflammatory response but exhibit instead a more substantial systemic inflammatory response, suggesting that a key driver of CAP severity may be the ability of the patient to generate an optimal local inflammatory response.

Serum and exhaled breath condensate inflammatory cytokines in community-acquired pneumonia: a prospective cohort study

BackgroundThe role and relationship between pro- and anti-inflammatory cytokines represents one of the least studied aspects of the pathogenesis of community-acquired pneumonia (CAP). The aim of the present study was to evaluate pro- and anti-inflammatory cytokines at both local (lung) and systemic (blood) levels and their relationship with the severity of the disease on admission and time for a patient to reach clinical stability during hospitalisation.MethodsThis was an observational, prospective, cohort study of hospitalised patients with a diagnosis of CAP at the IRCCS Policlinico Hospital, Milan, Italy, between April 2010 and January 2012. Ten pro-inflammatory cytokines (interleukin [IL]-1, IL-1α, IL-1β, IL-2, IL-6, IL-8, tumor necrosis factor [TNF]α and interferon [IFN]γ) and anti-inflammatory cytokines (IL-4 and IL-10) were measured in both serum and exhaled breath condensate within 24 h after hospital admission.ResultsA total of 74 patients (median age: 76 years; gender: 61 % male) were enrolled. The anti- to pro-inflammatory cytokine ratio was reduced in patients with severe disease on admission and prolonged time to reach clinical stability. This was due to lower levels of anti-inflammatory cytokines in the exhaled breath condensate and higher levels of pro-inflammatory cytokines in serum.ConclusionsDis-regulation between pro- and anti-inflammatory pathways might be a part of the pathogenic mechanisms that lead to severe infection and worse early clinical outcomes in CAP patients.

Cefditoren versus levofloxacin in patients with exacerbations of chronic bronchitis: serum inflammatory biomarkers, clinical efficacy, and microbiological eradication.

Background The aim of this open-label, randomized, parallel-group pilot study was to evaluate the efficacy of cefditoren pivoxil and levofloxacin in terms of speed of reduction in inflammatory parameters, clinical recovery, and microbiological eradication. Methods Forty eligible patients with acute exacerbation of chronic bronchitis (AECB) were randomized to receive cefditoren 200 mg twice a day for 5 days (n = 20) or levofloxacin 500 mg once daily for 7 days (n = 20). Results The inflammatory parameters which were significantly reduced at test-of-cure with respect to visit 1 were Krebs von den Lundgen-6 (KL-6) and interleukin-6. KL-6 decreased both in the overall study population (from 19 ± 11 UI/mL to 6 ± 8 UI/mL, P = 0.000) and in the cefditoren (from 19 ± 13 UI/mL to 8 ± 10 UI/mL, P = 0.006) and levofloxacin (from 19 ± 10 UI/mL to 5 ± 5 UI/mL, P = 0.000) arms. Similarly, interleukin-6 decreased both in the overall study population (from 13.35 ± 16.41 pg/mL to 3 ± 4.7 pg/mL, P = 0.000) and in the cefditoren (from 15.90 ± 19.54 pg/mL to 4.13 ± 6.42 pg/mL, P = 0.015) and levofloxacin (from 10.80 ± 12.55 pg/mL to 1.87 ± 1.16 pg/mL, P = 0.003) arms. At the end of treatment (test-of-cure, 6–9 days after drug initiation), the clinical success rate in the overall study population was 78%; the clinical cure rate was 80% in the cefditoren arm and 75% in the levofloxacin arm. Globally, bacteriological eradication at test-of-cure was obtained in 85% of the overall study population. Both treatments were well tolerated. Conclusion Cefditoren represents a valid option in the treatment of mild to moderately severe cases of AECB in the outpatient care setting. Moreover, the use of this cephalosporin is associated with a significant reduction of interleukin-6 and KL-6, two key mediators of lung inflammation and epithelial damage.

The burden of sinus disease in cystic fibrosis lung transplant recipients

Sinus disease (SD) in cystic fibrosis (CF) is a known risk factor for disease progression, the upper airways (UAW) being a site of primary colonization with Pseudomonas aeruginosa. UAW may function as reservoir for graft colonization after lung transplantation (LuTx), increasing risk of rejection. Aims of this study were to assess the burden of sinus disease in CF LuTx recipients, considering patient‐reported symptoms, endoscopically documented signs and microbiological isolates, comparing colonization between upper and lower airways.

Infections after lung transplantation

The good clinical result of lung transplantation is constantly undermined by the high incidence of infection, which negatively impacts on function and survival. Moreover, infections may also have immunological interactions that play a role in the acute rejection and in the development of chronic lung allograft dysfunction. There is a temporal sequence in the types of infection that affects lung allograft: in the first postoperative month bacteria are the most frequent cause of infection; following this phase, cytomegalovirus and Pneumocystis carinii are common. Fungal infections are particularly feared due to their association with bronchial complication and high mortality. Scrupulous postoperative surveillance is mandatory for the successful management of lung transplantation patients with respect to early detection and treatment of infections. This paper is aimed to address clinicians in the management of the major infectious complications that affect the lung transplant population.

Lobar Lung Transplantation From Deceased Donor: Monocentric Experience

INTRODUCTION Lung transplantation is considered a therapeutic option in selected patients affected by end-stage pulmonary disease. The mortality on the waiting list is mainly attributed to the shortage of the donor pool available for transplantation. There are various strategies to overcome this shortage; one of them is lobar transplantation. METHODS The aim of the current study was to analyze the outcome of lobar lung transplantation from deceased donors in our Lung Transplant Center. Overall survival, perioperative mortality and morbidity, problem on bronchial anastomosis, and chronic rejection were prospectively recorded in a 5-year time-frame. RESULTS From November 2010 to October 2015, we performed 100 lung transplantations; 6 of which (6%) were lobar transplantations from deceased donors. Three recipients were on an emergency list due to preoperative extracorporeal support. The causes of lobectomy leading to lobar transplantation were: size mismatch (3), iatrogenic vascular damage (2), and chronic atelectasis (1). One patient died 5 months after surgery for sepsis; and 5 patients were alive at the study end (median follow-up: 17.5 months). Prevalence of grade 3 primary graft dysfunction at 72 hours was 50%. One patient developed bronchial stenosis. No cases of chronic rejection were recorded. CONCLUSIONS Lobar transplantation can be considered a valid tool to overcome the donor pool shortage in selected cases; such a technique has proved particularly useful in critically ill patients who were scheduled in an emergency transplant program.

Additional file 1: Table SA. of Serum and exhaled breath condensate inflammatory cytokines in community-acquired pneumonia: a prospective cohort study

Complete analysis of cytokine levels in serum and exhaled breath condensate according to the severity of the disease on hospital admission of patients with community-acquired pneumonia (CAP). Table SB. Complete analysis of cytokine ratio according to the severity of the disease on hospital admission of patients with community-acquired pneumonia (CAP). Table SC. Complete analysis of cytokine levels and ratios in serum and exhaled breath condensate according to time to clinical stability (TCS). (DOC 275 kb)