Felipe Andreo

Endobronchial ultrasound-guided transbronchial needle aspiration for identifying EGFR mutations

The presence of somatic mutations of the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene in patients with advanced nonsmall cell lung cancer (NSCLC) correlates with a good response to tyrosine kinase inhibitors. The usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the detection of EGFR mutations in cells recovered from malignant mediastinal nodes in patients with NSCLC was assessed. All patients with lung adenocarcinoma or unspecified NSCLC referred for staging with EBUS-TBNA were included. Nodes with a short-axis diameter of >5 mm were sampled, and genomic DNA from metastatic tumour cells was obtained for analysis of exons 19 and 21. The impact of sampling on management was assessed. EGFR gene analysis of the EBUS-TBNA sample was feasible in 26 (72.2%) out of the 36 patients with lymph node metastasis. Somatic mutations of the EGFR gene were detected in tissue obtained through EBUS-TBNA in two (10%) out of 20 patients with metastasic lung adenocarcinoma. Malignant tissue samples obtained by EBUS-TBNA from patients with nodal metastasis of NSCLC are suitable for the detection of EGFR mutations in most cases, and this technique demonstrates mutated neoplastic cells in a tenth of patients with adenocarcinoma.

Secretion of interferon‐γ by human macrophages demonstrated at the single‐cell level after costimulation with interleukin (IL)‐12 plus IL‐18

The interferon (IFN)‐γ component of the immune response plays an essential role in combating infectious and non‐infectious diseases. Induction of IFN‐γ secretion by human T and natural killer (NK) cells through synergistic costimulation with interleukin (IL)‐12 and IL‐18 in the adaptive immune responses against pathogens is well established, but induction of similar activity in macrophages is still controversial, with doubts largely focusing on contamination of macrophages with NK or T cells in the relevant experiments. The possible contribution of macrophages to the IFN response is, however, an important factor relevant to the pathogenesis of many diseases. To resolve this issue, we analysed the production of IFN‐γ at the single‐cell level by immunohistochemistry and by enzyme‐linked immunosorbent spot (ELISPOT) analysis and unequivocally demonstrated that human macrophages derived from monocytes in vitro through stimulation with a combination of IL‐12 and IL‐18 or with macrophage colony‐stimulating factor (M‐CSF) were able to produce IFN‐γ when further stimulated with a combination of IL‐12 and IL‐18. In addition, naturally activated alveolar macrophages immediately secreted IFN‐γ upon treatment with IL‐12 and IL‐18. Therefore, human macrophages in addition to lymphoid cells contribute to the IFN‐γ response, providing another link between the innate and acquired immune responses.

Contribution of cell blocks obtained through endobronchial ultrasound-guided transbronchial needle aspiration to the diagnosis of lung cancer.

BackgroundConventional smears of samples obtained by endobronchial ultrasound with real-time transbronchial needle aspiration (EBUS-TBNA) have proven useful in lung cancer staging, but the value of additional information from cell-block processing of EBUS-TBNA samples has only been marginally investigated. This study focussed on the contribution of cell block analysis to the diagnostic yield in lung cancer.MethodsPatients referred for lung cancer diagnosis and/or staging by means of EBUS-TBNA were enrolled, the adequacy of the obtained samples for preparing cell blocks was assessed, and the additional pathologic or genetic information provided from cell block analysis was examined.ResultsIn 270 lung cancer patients referred for EBUS-TBNA (mean age, 63.3 SD 10.4 years) 697 aspirations were performed. Cell blocks could be obtained from 334 aspirates (47.9%) and contained diagnostic material in 262 (37.6%) aspirates, providing information that was additional to conventional smears in 50 of the 189 samples with smears that were non-diagnostic, corresponding 21 of these blocks to malignant nodes, and allowing lung cancer subtyping of 4 samples. Overall, cell blocks improved the pathologic diagnosis attained with conventional smears in 54 of the 697 samples obtained with EBUS-TBNA (7.7%). Cell blocks obtained during EBUS-TBNA also made epithelial growth factor receptor mutation analysis possible in 39 of the 64 patients with TBNA samples showing metastatic adenocarcinoma (60.1%). Overall, cell blocks provided clinically significant information for 83 of the 270 patients participating in the study (30.7%).ConclusionsCell-block preparation from EBUS-TBNA samples is a simple way to provide additional information in lung cancer diagnosis. Analysis of cell blocks increases the diagnostic yield of the procedure by nearly seven per cent and allows for genetic analysis in a sixty per cent of the patients with metastatic adenocarcinoma.

Value of procalcitonin, C-reactive protein, and neopterin in exacerbations of chronic obstructive pulmonary disease

Objective: The identification of biological markers in order to assess different aspects of COPD is an area of growing interest. The objective of this study was to investigate whether levels of procalcitonin (PCT), C-reactive protein (CRP), and neopterin in COPD patients could be useful in identifying the etiological origin of the exacerbation and assessing its prognosis. Methods: We included 318 consecutive COPD patients: 46 in a stable phase, 217 undergoing an exacerbation, and 55 with pneumonia. A serum sample was collected from each patient at the time of being included in the study. A second sample was also collected 1 month later from 23 patients in the exacerbation group. We compared the characteristics, biomarker levels, microbiological findings, and prognosis in each patient group. PCT and CRP were measured using an immunofluorescence assay. Neopterin levels were measured using a competitive immunoassay. Results: PCT and CRP showed significant differences among the three patient groups, being higher in patients with pneumonia, followed by patients with exacerbation (P < 0.0001). For the 23 patients with paired samples, PCT and CRP levels decreased 1 month after the exacerbation episode, while neopterin increased. Neopterin showed significantly lower levels in exacerbations with isolation of pathogenic bacteria, but no differences were found for PCT and CRP. No significant differences were found when comparing biomarker levels according to the Gram result: PCT (P = 0.191), CRP (P = 0.080), and neopterin (P = 0.109). However, median values of PCT and CRP were high for Streptococcus pneumoniae, Staphylococcus aureus, and enterobacteria. All biomarkers were higher in patients who died within 1 month after the sample collection than in patients who died later on. Conclusions: According to our results, biomarker levels vary depending on the clinical status. However, the identification of the etiology of infectious exacerbation by means of circulating biomarkers is encouraging, but its main disadvantage is the absence of a microbiological gold standard, to definitively demonstrate their value. High biomarker levels during an exacerbation episode correlate with the short-term prognosis, and therefore their measurement can be useful for COPD management.

Usefulness of consecutive biomarkers measurement in the management of community-acquired pneumonia

The aim of this study was to investigate whether procalcitonin (PCT), neopterin, C-reactive protein (CRP), and mid regional pro-atrial natriuretic peptide (MR-proANP) levels at admission and during the clinical course can be useful for the management of patients with pneumonia. The study population consisted of 75 patients with clinical and radiological diagnosis of pneumonia. Serum samples were collected at admission and during hospitalization. Complications were defined as intensive care unit (ICU) admission or death. The levels of PCT were significantly higher in pneumonia of definite bacterial origin in comparison to probable bacterial or unknown origin. The PCT levels were higher in pneumococcal pneumonia. The PCT and MR-proANP levels increased significantly according to the Pneumonia Severity Index (PSI). All biomarkers levels are higher in patients developing complications and who were dying. The serial levels of MR-proANP remain significantly elevated in patients developing complications and in patients classified in PSI and CURB-65 risk groups. In patients not developing complications, there is a significant decrease in the PCT levels. PCT can be useful for identifying pneumonia etiology. PCT and MR-proANP levels correlate with pneumonia severity rules. PCT and MR-proANP serial measurements can be useful for predicting short-term prognosis. Systemic biomarkers can provide additional information regarding clinical evolution, because these are dynamic and can be measured daily.

Sensitivity of linear endobronchial ultrasonography and guided transbronchial needle aspiration for the identification of nodal metastasis in lung cancer staging.

The aim of this study is to determine the sensitivity of real-time endobronchial ultrasonography (EBUS)-guided transbronchial needle aspiration (TBNA) in lung cancer staging. Short- and long-axis node diameters were measured during EBUS in patients referred for lung cancer staging and sensitivities for the identification of nodal malignancy at TBNA determined. Three hundred fifteen real-time EBUS-guided TBNA nodal sampling procedures were performed in 161 patients and in 87 of them, N2/N3 metastasis was confirmed (50.9%), eliminating the need for mediastinoscopy. The median (interquartile range [IQR]) short-axis diameters of the sampled mediastinal and lobar nodes were 11 (8-15) and 8 (7-12) mm, respectively. TBNA provided satisfactory samples from 269 nodes (85.4%) and a sensitivity of 100% for the identification of malignant TBNA samples was reached for a short-axis diameter cut-off of 5 mm and a short- to long-axis ratio of 0.5. The probability of malignancy was over 90% for nodes with a short-axis diameter >20 mm and 55% for round nodes (short- to long-axis ratio of 1). In 18 out of 50 patients with a normal mediastinal computed tomography (CT) scan, the technique identified enlarged nodes in the mediastinum (36%), mainly in the subcarinal region and confirmed mediastinal malignancy in 8 (10%). Real-time EBUS-guided TBNA obtains satisfactory node samples in almost 90% of cases and improves the identification of enlarged nodes in patients with a normal mediastinum at CT. If sampling all nodes with a short-axis diameter of > or =5 mm and a short- to long-axis ratio > or =0.5, a sensitivity of 100% for the cytologic identification of malignant nodes can be expected.

Tuberculosis en personal sanitario de un hospital general

BACKGROUND AND OBJECTIVE: Tuberculosis is an occupational disease in health care workers. The objective of our study was to review tuberculosis cases in health care professionals from a general hospital and to determine their incidence in relation to the general population. PATIENTS AND METHOD: This was a retrospective study of tuberculosis cases among health care workers in a university hospital from 1988 to 2002, evaluating the annual cumulative incidence. RESULTS: 21 tuberculosis cases were found in health care workers. Pulmonary disease was the most frequent type (62%) followed by pleural effusion (28%). The most affected professional category were medical residents (38%) with the emergency service (48%) being the work place with the highest risk. The cumulative incidence in our hospital was higher in relation to the general population although there was a variability between both populations. CONCLUSIONS: There is risk of tuberculosis transmission among health care workers, principally in the emergency service and the pathology and microbiological departments. A concerted effort is needed to maintain prevention measures in the work place where there is a high risk of infection.

Biomarkers in the management of COPD

Chronic obstructive pulmonary disease (COPD) is still a leading cause of morbidity and mortality worldwide, with a huge socioeconomic impact. New strategies for the management of COPD are required, not only for identifying the origin of the exacerbation episodes, but also to assess an individual risk for each patient. A promising approach is to measure systemic biomarkers and correlate their levels with exacerbation characteristics and clinical prognosis of the disease. Several biomarkers have clearly correlated with the aetiology of lower respiratory tract infections and the response to antibiotic treatment, indicating a potential utility in COPD exacerbation. Nevertheless, the results available at the moment, together with the absence of a gold standard for identifying the aetiological origin of an exacerbation, impedes establishing the real utility of these biomarkers for this concrete task. Regarding the clinical evolution and prognosis, several clinical characteristics have been correlated to biomarker levels. The potential influence of many factors (severity of the disease, presence of comorbidities and treatment) leads to the conclusion that, in the future, the best option would be to monitor levels individually, rather than establishing cut-off points for the general COPD population.

Utility of pneumococcal urinary antigen detection in diagnosing exacerbations in COPD patients

The aim of this study was to evaluate the utility of pneumococcal urinary antigen detection (Binax Now Streptococcus pneumoniae Antigen Test) in diagnosing pneumococcal exacerbation of chronic obstructive pulmonary disease (COPD). Forty-six patients with S. pneumoniae isolation in sputum culture were studied (29 collected in stable period and 17 collected during exacerbation). In the 29 patients with samples collected in a stable period the antigen was detected in 3 cases (10.3%) using nonconcentrated urine (NCU), and in 12 cases (41.4%) using concentrated urine (CU). Regarding patients recruited during an exacerbation period, the antigen was detected in 3 cases (17.6%) using NCU, and in 13 cases (76.5%) when CU was used. For the evaluation of the specificity of the ICT test we also tested 72 cases in which pneumococcus was not isolated in the sputum sample. ICT was positive in 1NCU and 9CU of these patients. To have had at least one previous exacerbation (P=0.024), at least one exacerbation that required hospitalization (P=0.027), and a pneumonia episode in the year before (P=0.010) had statistically significant associated with the detection of specific antigen in CU. Using NCU, the only significant association was found when a previous pneumonia in the year before had occurred (P=0.006). In summary, a positive result of pneumococcal urinary antigen from a COPD patient, in both bronchial exacerbation and pneumonia, should be evaluated with caution because the antigen detected could be related with previous infectious episode.

Utilidad de una consulta monográfica de diagnóstico rápido de cáncer de pulmón. Aportaciones de la ecobroncoscopia

OBJECTIVE To analyse the results obtained in the diagnosis and staging of lung cancer (LC) by a Lung Cancer Rapid Diagnosis Unit (LC-RDU) in which real-time endobronchial ultrasound-guided transbronchial needle aspiration (RT-EBUS guided-TBNA) is performed as part of the clinical evaluation of the patient prior to treatment. METHOD A four year observational study was conducted on a group of patients evaluated due to suspicion of LC in an LC-RDU. The times and the techniques required for the diagnosis and identifying the level of the disease in the initial staging were recorded. RESULTS Out of a total of 678 patients seen in the LC-RDU, the diagnosis in 352 was confirmed in one or more histopathology samples. In 170 patients (48.2%) the diagnosis was made with biopsies and/ or cytology samples obtained by fibrobronchoscopy, and RT-EBUS guided-TBNA confirmed the clinical suspicion in 70 patients (19.9%). In the 280 patients with SCLC, 166 RT-EBUS guided-TBNA were performed for staging (59.3%), and in 105 of them the technique only showed local disease (37.5%). Therapeutic surgery was performed on 83 of these patients, and was radical in 73 cases (87.9%). CONCLUSION In half of the patients referred to the LC-RDU due to suspected LC, the diagnosis was confirmed in 75% of cases using endoscopic techniques. RT-EBUS guided-TBNA was the diagnostic technique in 20% of the cases, for staging in more than half of them, and led to reduced waiting times for the diagnosis and starting treatment.