Parapneumonic effusion and thoracic empyema in adults. Clinical aspects, microbiology and frequency of surgical outcome.

BACKGROUND: To date, information about the outcome of patients with parapneumonic effusion and empyema is limited. OBJECTIVE: To describe the clinical characteristics, the microbiological study and the frequency and type of surgical treatment in adult patients with parapneumonic effusion or empyema. METHOD: A prospective cross-sectional study of patients admitted with parapneumonic effusion or empyema, from August 2011 to July 2014, in a reference hospital for respiratory diseases in Mexico City, was conducted. Clinical characteristics, microbiology, risk categories for poor prognosis in empyema and frequency and type of surgical treatment were studied. RESULTS: We studied 284 patients whose median age was 47 years, 75% were men, and 57.7% were transferred from other hospitals. In 38.5% of the cases a microorganism was identified and there was a predominance of Gram negative. 153 (53.9%) required surgical treatment, of which 90% were thoracotomy with decortication. Hospital mortality was 5.63%. CONCLUSIONS: Most of the patients arrived in advanced stages of the disease, so more than half required surgery, of which 90% was decortication. It is desirable to favor mechanisms for early diagnosis and treatment to reduce the need for surgical treatment.

ANTECEDENTES: La información sobre el tipo y la frecuencia del tratamiento quirúrgico en los casos de empiema torácico es escasa. OBJETIVO: Describir las características clínicas, el estudio microbiológico y la frecuencia y el tipo de tratamiento quirúrgico en pacientes adultos con derrame pleural paraneumónico o empiema. MÉTODO: Estudio transversal prospectivo de pacientes con diagnóstico de derrame pleural paraneumónico o empiema, de agosto de 2011 a julio de 2014, en un hospital de referencia para enfermedades respiratorias en la Ciudad de México. Se estudiaron las características clínicas, las categorías de riesgo para mal pronóstico en empiema y la frecuencia y el tipo de tratamiento quirúrgico. RESULTADOS: Se estudiaron 284 pacientes cuya mediana de edad fue de 47 años y el 75% eran hombres. El 57.7% fueron traslados de otros hospitales. En el 38.8% de los casos se identificó un microorganismo, con predominio de gramnegativos. Requirieron tratamiento quirúrgico 153 pacientes (53.9%), de los cuales en el 90% fue toracotomía con lavado y decorticación. La mortalidad hospitalaria fue del 5.63%. CONCLUSIONES: La mayor parte de los pacientes llegaron en etapas avanzadas de la enfermedad, y por ello más de la mitad requirieron cirugía, de los cuales en el 90% fue lavado y decorticación. Es deseable favorecer mecanismos para realizar un diagnóstico y un tratamiento tempranos con el fin de disminuir la necesidad de tratamiento quirúrgico.

Case-control study about magnitude of exposure to wood smoke and risk of developing lung cancer.

INTRODUCTION: Exposure to biomass combustion products, particularly firewood, has been considered as a potential carcinogen for developing lung cancer. In this regard, current evidence is widely heterogeneous; besides, in most studies, wood smoke exposure is not appropriately quantified, which further complicates the analysis of wood smoke as a potential carcinogen. The aim of the present study was to estimate the risk of developing lung cancer according to the degree of exposure to wood smoke in patients who use firewood for cooking. MATERIAL AND METHODS: We performed a case-control study that included 482 patients with lung cancer (cases) and 592 hospital controls. Exposure to wood smoke was evaluated as a dichotomous variable (i.e. yes or no); in patients with prior wood smoke exposure, an index of exposure in hours per year was calculated (WSEI). Using bivariate and multivariate logistic regression analyses, the odds ratio (OR) between wood smoke exposure and lung cancer were calculated. RESULTS: The ORs for developing lung cancer (raw and adjusted) for a WSEI > 100 h/year were OR 1.55 [95% confidence interval (CI), 1.06-2.26) and OR 2.26 (95% CI, 1.50-3.40), respectively; the ORs (raw and adjusted) for WSEI >300 h/year were OR 1.76 (95% CI, 1.06-2.91) and OR 3.19 (95% CI, 1.83-5.55), respectively. CONCLUSIONS: Exposure to wood smoke is a risk factor for lung cancer; furthermore, this effect maintains a dose-response relationship which has a multiplicative effect with smoking.

Accuracy of closed pleural biopsy in the diagnosis of malignant pleural effusion.

OBJECTIVE: Previous studies have demonstrated that closed pleural biopsy (CPB) has a sensitivity of less than 60% for diagnosing malignancy. Therefore, controversy has recently emerged regarding the value of CPB as a diagnostic test. Our objective was to assess the accuracy of CPB in diagnosing malignancy in patients with pleural effusion. METHODS: This was a prospective 8-year study of individuals who underwent CPB to establish the etiology of pleural effusion. Information on each patient was obtained from anatomopathological reports and medical records. When CPB findings showed malignancy or tuberculosis, the biopsy was considered diagnostic, and that was the definitive diagnosis. In cases in which biopsy histopathological findings were nonspecific, a definitive diagnosis was established on the basis of other diagnostic procedures, such as thoracoscopy, thoracotomy, fiberoptic bronchoscopy, biochemical and cellular measurements in pleural fluid, and/or microbiological tests. The accuracy of CPB was determined with 2 × 2 contingency tables. RESULTS: A total of 1034 biopsies from patients with pleural effusion were studied. Of those, 171 (16.54%) were excluded from the accuracy analysis either because of inadequate samples or insufficient information. The results of the accuracy analysis were as follows: sensitivity, 77%; specificity, 98%; positive predictive value, 99%; negative predictive value, 66%; positive likelihood ratio, 38.5; negative likelihood ratio, 0.23; pre-test probability, 2.13; and post-test probability, 82. CONCLUSIONS: CPB is useful in clinical practice as a diagnostic test, because there is an important change from pre-test to post-test probability.

Accuracy of closed pleural biopsy in the diagnosis of malignant pleural effusion / Exactitud de la biopsia pleural cerrada para el diagnóstico de derrame pleural maligno

ABSTRACT Objective: Previous studies have demonstrated that closed pleural biopsy (CPB) has a sensitivity of less than 60% for diagnosing malignancy. Therefore, controversy has recently emerged regarding the value of CPB as a diagnostic test. Our objective was to assess the accuracy of CPB in diagnosing malignancy in patients with pleural effusion. Methods: This was a prospective 8-year study of individuals who underwent CPB to establish the etiology of pleural effusion. Information on each patient was obtained from anatomopathological reports and medical records. When CPB findings showed malignancy or tuberculosis, the biopsy was considered diagnostic, and that was the definitive diagnosis. In cases in which biopsy histopathological findings were nonspecific, a definitive diagnosis was established on the basis of other diagnostic procedures, such as thoracoscopy, thoracotomy, fiberoptic bronchoscopy, biochemical and cellular measurements in pleural fluid, and/or microbiological tests. The accuracy of CPB was determined with 2 × 2 contingency tables. Results: A total of 1034 biopsies from patients with pleural effusion were studied. Of those, 171 (16.54%) were excluded from the accuracy analysis either because of inadequate samples or insufficient information. The results of the accuracy analysis were as follows: sensitivity, 77%; specificity, 98%; positive predictive value, 99%; negative predictive value, 66%; positive likelihood ratio, 38.5; negative likelihood ratio, 0.23; pre-test probability, 2.13; and post-test probability, 82. Conclusions: CPB is useful in clinical practice as a diagnostic test, because there is an important change from pre-test to post-test probability.

RESUMEN Objetivo: Estudios previos demuestran que la biopsia pleural cerrada (BPC) para diagnóstico de malignidad tiene una sensibilidad menor al 60%, por lo que recientemente ha despertado controversia su valor como prueba diagnóstica. Nuestro objetivo fue evaluar la exactitud de la BPC para diagnóstico de malignidad en pacientes con derrame pleural. Métodos: Estudio prospectivo de 8 años en individuos que se sometieron a la realización de BPC para establecer la etiología del derrame. La información de cada paciente se tomó de los registros de anatomopatología y del expediente clínico. Cuando el resultado de la BPC demostró malignidad o tuberculosis, esto se tomó como biopsia diagnóstica y quedó éste como diagnóstico definitivo. En los casos en que el resultado del estudio histopatológico de la biopsia resultó inespecífico, el diagnóstico definitivo se estableció en base a otros procedimientos diagnósticos, como toracoscopia, toracotomía, fibrobroncoscopia, estudio bioquímico y celular del líquido pleural y/o pruebas microbiológicas. Mediante una tabla de contingencia de 2 × 2 se midieron los indicadores para una prueba diagnóstica. Resultados: Se estudiaron 1034 biopsias de pacientes con derrame pleural, de las cuales se excluyeron 171 (16.54%) por muestra inadecuada o información insuficiente. El desempeño para malignidad fue: sensibilidad, 77%; especificidad, 98%; valores predictivos positivo y negativo, 99% y 66%, respectivamente; índices de probabilidad positivo y negativo, 38.5 y 0.23, respectivamente; probabilidad antes y después de la prueba, 2.13 y 82, respectivamente. Conclusión: La BPC es útil como prueba diagnóstica en la práctica clínica, debido a que produce un cambio importante de la probabilidad antes de la prueba a la probabilidad después de la prueba.