C. Alemán

Metalloproteinases and tissue inhibitors of metalloproteinases in exudative pleural effusions

The aim of this study was to assess the expression of several metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in exudative pleural effusions, and their relationship with inflammatory and fibrinolytic mediators in parapneumonic effusions. The study included 51 parapneumonic effusions (30 empyema or complicated parapneumonic, 21 noncomplicated parapneumonic), 28 tuberculous, 30 malignant and 30 transudates. Inflammatory markers (tumour necrosis factor-α, interleukin-8, polymorphonuclear elastase), fibrinolytic system variables (tissue plasminogen activator (PA), urokinase PA (u-PA), plasminogen activation inhibitor (PAI)-1, PAI-2), and several MMPs (MMP-1, MMP-2, MMP-8, MMP-9) and TIMPs (TIMP-1, TIMP-2) were determined by ELISA in plasma and pleural fluid. Elevated MMP-2 and TIMP-1 concentrations were observed in all the pleural fluid samples studied. The group of empyema or complicated parapneumonic effusions showed higher MMP-1, MMP-8 and MMP-9 concentrations than the remaining exudates. There was no correlation between MMP and TIMP levels in plasma and pleural fluid in this group of effusions. In parapneumonic effusions, MMP-1, MMP-8 and MMP-9 showed a positive correlation with the inflammatory markers and with u-PA and PAI-1. Moreover, there was a relationship between MMP-8 concentration in pleural fluid and pleural thickening at the end of treatment. In conclusion, elevated metalloproteinase-1, -8 and -9 expression was found in parapneumonic pleural effusions. These metalloproteinases could be implicated in the local inflammatory response existing in this group of effusions.

Pleural-fluid myeloperoxidase in complicated and noncomplicated parapneumonic pleural effusions

The diagnostic accuracy of myeloperoxidase (MPO) in pleural fluid, for differentiating between complicated and noncomplicated parapneumonic pleural effusions (PPE) evaluated prospectively. Seventy patients aged >18 yrs with PPE (36 complicated and 34 noncomplicated) were studied after admission to a tertiary referral teaching hospital. MPO concentration was measured in plasma and pleural fluid using a double-antibody competitive radioimmunoassay. The concentrations of MPO in complicated and noncomplicated PPE were compared using a Mann-Whitney U-test and multiple logistic regression models were used to predict the odds that an effusion was complicated. MPO pleural-fluid concentrations were significantly higher in complicated than in noncomplicated PPE. After excluding purulent effusions, pleural-fluid MPO was the marker that best differentiated between the two types of PPE: the area under the receiver operating characteristic curve was 0.912, the sensitivity was 87.5% and the specificity was 85.1% at a cut-point limit of 3.000 µg·L−1. The authors concluded that the concentration of pleural-fluid myeloperoxidase helps to differentiate between nonpurulent complicated and noncomplicated parapneumonic pleural effusions.

Diagnostic accuracy of pleural fluid polymorphonuclear elastase in the differentiation between pyogenic bacterial infectious and non-infectious pleural effusions.

Background and Objectives: To establish the diagnostic accuracy of the markers of neutrophil activity (elastase and lysozyme) determined in pleural fluid, for differentiating between pyogenic bacterial infectious and non-infectious pleural effusions. Patients and Methods: At our tertiary referral teaching hospital, 160 patients over 14 years with pleural effusion (PE), classified as pyogenic bacterial infectious (41 parapneumonic complicated, 32 parapneumonic non-complicated) and non-infectious (32 neoplasm and 55 undiagnosed pleural exudates) were examined in a prospective study. Polymorphonuclear elastase (PMN-E) was determined by an immunoactivation method and lysozyme by a turbidimetric method. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic accuracy. Results: Pleural fluid PMN-E was the biochemical marker that best differentiated between pyogenic bacterial infectious and non-infectious PE. The ROC area under the curve (AUC) for PMN-E was 0.8276. A PMN-E value over 230 µg/l diagnosed infectious PE with a specificity of 0.81 and a sensitivity of 0.74. The ROC AUC for proteins plus lactate dehydrogenase was 0.7430. Differences between the two ROC curves were significant (p = 0.032). After excluding purulent parapneumonic complicated PE, the sensitivity of a pleural fluid PMN-E value equal to or greater than 230 µg/l was 0.64 and the specificity 0.81. Conclusions: Pleural fluid PMN-E was the marker that best differentiated infectious from non-infectious PE, and PMN-E values lower than 230 µg/l suggest non-infectious PE.

Factors Influencing Length of Hospital Stay in Patients with Bacterial Pleural Effusion

Background: Factors influencing length of hospital stay have been poorly analyzed in parapneumonic pleural effusions (PPE). Objectives: The aim of this work is to identify the variables that determine increased hospital stay in patients with infectious pleural effusion (PE). Patients and Methods: We analyzed 112 patients with PE: empyema, complicated parapneumonic and non-complicated parapneumonic. Epidemiologic, biochemical, therapeutic and radiological variables were analyzed. Correlations with hospital stay were studied using the Student’s t test, analysis of variance, Mann-Whitney U-test and linear regression model. Results: Among the 112 patients studied, there were 32 empyema, 50 complicated and 30 non-complicated parapneumonic cases. The median of length stay for all patients was 17 days. Longer hospitalization was required in patients with empyemic PE (p = 0.015), patients with underlying diseases (p = 0.003), those needing pleural drainage (p = 0.005) or decortication (p = 0.043) and those presenting unfavorable radiological outcome after treatment (p = 0.02). Biochemical parameters associated with longer hospital stay were elevated pleural fluid polymorphonuclear elastase (p = 0.001, r = 0.307) and lactate dehydrogenase (p = 0.001, r = 0.312). After linear regression analysis, only underlying disease, pleural drainage and pleural fluid polymorphonuclear elastase values remained in the model, explaining 23.1% of the variability of days of hospitalization. Conclusions: The patients with PPE and empyema who required longer hospitalization were those with purulent fluid, underlying disease, surgical drainage and/or decortication, with unfavorable radiological outcome and higher pleural fluid levels of lactate dehydrogenase and polymorphonuclear elastase.

Engrosamiento pleural residual en la pleuritis tuberculosa. Factores asociados

Fundamento Estudio de los factores asociados al engrosamiento pleural residual en el derrame pleural tuberculoso. Pacientes y metodos Estudiamos a 39 pacientes con derrame pleural tuberculoso. A todos se les realiza una radiografia de torax al finalizar el tratamiento. Se valoran datos de la historia clinica, analisis del liquido pleural y radiografia de torax en el momento del diagnostico. Se define como engrosamiento pleural residual aquel engrosamiento visible mayor de 2 mm en la porcion lateral e inferior de la radiografia posteroanterior de torax. Resultados Un 36% de los pacientes presentaron engrosamiento pleural residual. La edad media de los pacientes fue significativamente superior, los varones presentaron un riesgo superior de desarrollar esta afeccion (RR 3,86) y ningun paciente en los que se observo crecimiento de Mycobaterium tuberculosis en medio de Lowenstein-Jensen presento complicaciones pleurales. Conclusion El engrosamiento pleural residual es una complicacion frecuente del derrame pleural tuberculoso. El engrosamiento pleural residual en la pleuritis tuberculosa se observa con mayor frecuencia en los varones y en pacientes de mayor edad y en los casos en que el cultivo del liquido pleural es negativo para Mycobacterium tuberculosis .

Bronquiolitis obliterante con neumonía organizativa asociada a Legionella pneumophila

Bronchilitis obliterans organizing pneumonia (BOOP) is an unusual pulmonary condition. The clinical features and the radiologic findings are useful for the diagnosis of BOOP. However it is necessary to confirm its presence by an open or transbronchial pulmonary biopsy specimen. BOOP is usually idiopathic, although it may also occur in association with connective tissue disease, some haemathologic disorders and in response to viral infections. The association of Legionella pneumophila infection with BOOP is very rare.

Relación de la edad con el manejo de los pacientes diagnosticados de neoplasia en un Servicio de Medicina Interna

Aim: To determine whether age is a factor affecting the management of patiens diagnosed with neoplastic disease in an internal medicine service. Patients and methods: Prospective study of 388 patients diagnosed with cancer in the internal medicine service of a large public health teaching hospital. We evaluated clinical characteristics, diagnostic procedures, types and stage of neoplasm, referral after hospital discharge and treatment. A comparative study based on age was performed between patients 65 years older and patients under this age. Results: The 388 cancer patiens accounted for 12% of hospital admissions in our service. Among the total, 62% were 65 years old. Constitutional syndrome, the most frequently associated symptom and the main reason for the consultation, was more common in the 65year-old group. Lung cancer was predominant in men and hematologic neoplasms in women. Patients 65 were referred more frequently to internal medicine physicians, general practitioners and home palliative assistance services (p<0.05) and they received only palliative treatment in a greater percentage of cases (50% vs. 37%, p=0.001). Conclusions: The incidence of neoplasms in our service was high (12%), with a considerable percentage of patients in advanced phases of the disease (83%). Age was not related to diagnostic methods nor was it determinant in the staging, but it did have repercussions on treatment; patients 65 received palliative treatment alone more often than younger patients.