Cambios en los parámetros bioquímicos del líquido pleural entre 2 toracocentesis consecutivas para diferenciar derrames malignos de benignos / Detection of Pleural Fluid Biochemistry Changes in Two Consecutive Thoracenteses for Differentiating Malignant from Benign Effusions

Objetivo: Evaluar si los cambios en los parámetros bioquímicos del líquido pleural (LP) entre 2 toracocentesis sucesivas permiten predecir derrames pleurales (DP) malignos o benignos. Métodos: Estudio retrospectivo de los pacientes con exudado linfocitario y citología negativa para malignidad que se sometieron a una segunda toracocentesis en nuestro centro durante los últimos 15 años (muestra de derivación), y en los que se alcanzó un diagnóstico final. Las diferencias absolutas (Δa) o porcentuales (Δp) de diferentes parámetros bioquímicos del LP capaces de predecir la naturaleza maligna o benigna del DP en la muestra de derivación se evaluaron en una población independiente. Resultados: Se incluyeron 214 pacientes con DP (70 malignos y 144 benignos) en la muestra de derivación. Las Δp LDH (lactato deshidrogenasa) > 0%, Δp neutrófilos > -10% (cualquier aumento o bien un descenso inferior al 10%), y Δa proteínas < 0,1 g/dL (cualquier descenso o bien un aumento inferior a 0,1 g/dL) entre la segunda y primera toracocentesis mostraron unas odds ratio de 6,4, 3,9 y 2,1 para discriminar DP maligno de benigno, respectivamente. La presencia de las 3 condiciones conjuntamente se asoció con una likelihood ratio positiva de 5,6, mientras que la ausencia de cualquiera ellas se asoció con una likelihood ratio negativa de 0,04 para predecir malignidad. Los resultados se reprodujeron en la población de validación. Conclusión: El aumento de LDH y neutrófilos, junto con el descenso de proteínas en una segunda toracocentesis, aumenta la probabilidad de que el origen del DP sea neoplásico, mientras que lo contrario la reduce significativamente

Objective: To assess whether changes in pleural fluid (PF) biochemistries between two consecutive thoracenteses enable clinicians to predict malignant or benign pleural effusions (PE). Methods: Retrospective study of patients with lymphocytic exudates and negative PF cytology, who underwent a second thoracentesis in our center in the last 15 years in whom a final diagnosis was reached (derivation sample). Absolute (Δa) and percentage differences (Δp) in PF biochemistries which predicted a malignant or benign PE in the derivation sample were evaluated in an independent population (validation sample). Results: The derivation sample included 214 PE patients (70 malignant and 144 benign PE). Δp lactate dehydrogenase (LDH) >0%, Δp neutrophils >-10% (any increase or less than 10% decrease) and Δa protein <0.1g/dL (any increase or less than 0.1g/dL decrease) between the second and the first thoracentesis had an odds ratio of 6.4, 3.9 and 2.1, respectively, to discriminate malignant from benign PE. The presence of the three conditions together had a positive likelihood ratio of 5.6, whereas the absence of any of the 3 parameters had a likelihood ratio of 0.04 for predicting malignancy. These results were reproduced in the validation sample. Conclusion: An increase in LDH and neutrophils along with a decrease in protein in a second thoracentesis increase the probability of malignant PE, while the opposite reduces it significantly

Detection of Pleural Fluid Biochemistry Changes in Two Consecutive Thoracenteses for Differentiating Malignant from Benign Effusions. / Cambios en los parámetros bioquímicos del líquido pleural entre 2 toracocentesis consecutivas para diferenciar derrames malignos de benignos.

OBJECTIVE: To assess whether changes in pleural fluid (PF) biochemistries between two consecutive thoracenteses enable clinicians to predict malignant or benign pleural effusions (PE). METHODS: Retrospective study of patients with lymphocytic exudates and negative PF cytology, who underwent a second thoracentesis in our center in the last 15 years in whom a final diagnosis was reached (derivation sample). Absolute (Δa) and percentage differences (Δp) in PF biochemistries which predicted a malignant or benign PE in the derivation sample were evaluated in an independent population (validation sample). RESULTS: The derivation sample included 214 PE patients (70 malignant and 144 benign PE). Δp lactate dehydrogenase (LDH) >0%, Δp neutrophils >-10% (any increase or less than 10% decrease) and Δa protein <0.1g/dL (any increase or less than 0.1g/dL decrease) between the second and the first thoracentesis had an odds ratio of 6.4, 3.9 and 2.1, respectively, to discriminate malignant from benign PE. The presence of the three conditions together had a positive likelihood ratio of 5.6, whereas the absence of any of the 3 parameters had a likelihood ratio of 0.04 for predicting malignancy. These results were reproduced in the validation sample. CONCLUSION: An increase in LDH and neutrophils along with a decrease in protein in a second thoracentesis increase the probability of malignant PE, while the opposite reduces it significantly.

Development and Validation of the COMPLES Score for Differentiating Between Tuberculous Effusions with Low Pleural pH or Glucose and Complicated Parapneumonic Effusions.

BACKGROUND: The frequency of "complicated" pleural effusions (CPE) (i.e., pleural fluid pH ≤ 7.2 and/or glucose ≤60 mg/dL) of tuberculous origin (CTPE) is not well reported. This study aims to quantify their prevalence, and develop a score to differentiate CTPE from complicated parapneumonic effusions (CPPE). METHODS: Retrospective analysis of databases from three Spanish hospitals which included patients with CTPE and CPPE. Forty percent of the study population served to generate a scoring system (COMPLES, COMplicated PLeural Effusion Score) that was further validated in the remaining 60 %. RESULTS: During the study period (1992-2015) 549 patients were diagnosed with tuberculous effusions and 434 parapneumonic effusions, of whom 25 and 64 %, respectively, had CPE. COMPLES was based on the combination of pleural fluid adenosine deaminase (ADA), the percentage of mononuclear cells (MNC %), pH, and age. The cutoff values and assigned scores were: ADA (<46 IU/L [0 points], 46-100 IU/L [4 points], ≥100 IU/L [6 points]), MNC % (<10 % [0 points], 10-50 [3 points], >50 [8 points]), pH (<7.07 [0 points], 7.07-7.20 [3 points], >7.20 [5 points]), and age (≥30 [0 points], <30 years [3 points]). A sum of 12 or more points had 97 % sensitivity, 92 % specificity, likelihood ratio positive 12.3, likelihood ratio negative 0.03, and area under the curve of 0.947 for identifying CTPE versus CPPE in the validation set. CONCLUSIONS: CPE is not an unusual presentation of tuberculosis. A simple new scoring system provides a reliable tool for differentiating between CTPE and CPPE.

Diagnostic accuracy of adenosine deaminase and lymphocyte proportion in pleural fluid for tuberculous pleurisy in different prevalence scenarios.

BACKGROUND: Tuberculous pleural effusion (TPE) is a paucibacillary manifestation of tuberculosis, so isolation of Mycobacterium tuberculosis is difficult, biomarkers being an alternative for diagnosis. Adenosine deaminase (ADA) is the most cost-effective pleural fluid marker and is routinely used in high prevalence settings, whereas its value is questioned in areas with low prevalence. The lymphocyte proportion (LP) is known to increase the specificity of ADA for this diagnosis. We analyse the diagnostic usefulness of ADA alone and the combination of ADA ≥ 40 U/l (ADA(40)) and LP ≥ 50% (LP(50)) in three different prevalence scenarios over 11 years in our area. MATERIALS AND METHODS: Biochemistry, cytology and microbiology studies from 472 consecutive pleural fluid samples were retrospectively analyzed. ADA and differential cell count were determined in all samples. We established three different prevalence periods, based on percentage of pleural effusion cases diagnosed as tuberculosis: 1998-2000 (31.3%), 2001-2004 (11.8%), and 2005-2008 (7.4%). ROC curves, dispersion diagrams and pre/post-test probability graphs were produced. TPE accounted for 73 episodes (mean prevalence: 15.5%). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for ADA(40) were 89%, 92.7%, 69.2% and 97.9%, respectively. For ADA(40)+LP(50) the specificity and PPV increased (98.3% and 90%) with hardly any decrease in the sensitivity or NPV (86.3% and 97.5%). No relevant differences were observed between the three study periods. CONCLUSIONS/SIGNIFICANCE: ADA remains useful for the diagnosis of TPE even in low-to-intermediate prevalence scenarios when combined with the lymphocyte proportion.

Bilateral pleural effusion and interstitial lung disease as unusual manifestations of Kikuchi-Fujimoto disease: case report and literature review.

BACKGROUND: Kikuchi-Fujimoto's disease (KFD), also called histiocytic necrotizing lymphadenitis, is a rare, idiopathic and self-limited condition usually characterized by cervical lymphadenopathy and fever, most often affecting young patients. Aetiology is unknown. Differential diagnosis includes mainly malignant lymphoma, tuberculous lymphadenitis and systemic lupus erythematosus (SLE), so early diagnosis is crucial. Pleuropulmonary involvement due to isolated KFD has been seldom reported. CASE PRESENTATION: a 32-year-old man, on treatment for iatrogenic hypothyroidism, was admitted due to high grade fever and painful cervical lymphadenopathies. KFD was diagnosed by lymph node biopsy. Some days after admission the patient got worse, he developed generalized lymphadenopathy, bilateral pleural effusion and interstitial lung disease. All of them resolved with prednisone and after two years of following up he remains asymptomatic and without evidence of any other associated disease. CONCLUSION: Pleural effusion and interstitial lung disease are very uncommon manifestations of KFD. In our experience, treatment with oral prednisone was effective.