Utilidad de la Beta2-transferrina y la proteína Beta-traza en el diagnóstico de fístula de líquido cefalorraquídeo / Beta2-transferrin and Beta-trace protein in the diagnosis of cerebrospinal fluid fistula

Introducción. El diagnóstico precoz de las fístulas de líquido cefalorraquídeo (LCR) minimiza el riesgo de que los pacientes desarrollen graves complicaciones. Una herramienta diagnóstica es demostrar la presencia de LCR en las secreciones nasales, óticas y heridas quirúrgicas mediante el uso de marcadores bioquímicos específicos. El objetivo del trabajo es evaluar la utilidad de la β2-transferrina (β2-Tr) y la proteína β-traza (p-βT) en el diagnóstico de la fístula de LCR. Material y métodos. Se realizó la detección de β2-Tr y la medición de p-βT en 68 muestras de secreciones nasales, óticas y heridas quirúrgicas, procedentes de 54 pacientes con sospecha de presentar una fístula de LCR. El diagnóstico fue confirmado por criterios clínicos y otras pruebas diagnósticas. Se calcularon la sensibilidad y la especificidad diagnóstica, el valor predictivo positivo (VPP) y negativo (VPN). Para la p-βT se obtuvo el punto de corte óptimo mediante un análisis de curva ROC. Resultados. Para la β2-Tr se obtuvo una sensibilidad del 83%, especificidad del 96%, VPP del 95% y VPN del 86%. Para la p-βT, se obtuvo un área bajo la curva de 0,981. Para un punto de corte óptimo de 1,14mg/L, se obtuvo una sensibilidad del 92%, especificidad del 95%, VPP del 96% y VPN del 91%. El punto de corte con un VPN del 100% fue de 0,64mg/L. Conclusiones. La β2-Tr y la p-βT pueden utilizarse como marcadores de la existencia de fístula de LCR por su elevada sensibilidad y especificidad diagnóstica. Se concluye que un valor de p-βT ≥ 1,14mg/L indica fístula de LCR y un valor ≤ 0,64mg/L la descarta. Valores entre 0,64 y 1,14mg/L no son concluyentes y sería necesario realizar la detección de β2-Tr (AU)

Introduction. Early diagnosis of cerebrospinal fluid (CSF) fistula minimizes the risk of severe complications for patients. A diagnostic approach consists in revealing the presence of CSF in nasal, ear, and surgical wound secretions. The aim of this work is to evaluate the usefulness of β2-transferrin (β2-Tr) and β-trace protein (p-βT) as markers for the diagnosis of a CSF fistula. Material and methods. A total of 68 samples of nasal, ear, and surgical wound secretions were taken and analysed from 54 patients with clinical suspicion of a CSF fistula. β2-Tr and p-βT were determined in all fluids. The CSF fistula was diagnosed by clinical criteria and other diagnostic procedures. Sensitivity and specificity, as well as positive (PPV) and negative (NPV) predictive values, were calculated. The optimal cut-off point for p-βT was obtained using a ROC curve analysis. Results. For β2-Tr, a sensitivity of 83%, a specificity of 96%, a PPV of 95% and a NPV of 86% were obtained. For the p-βT ROC curve analysis, the area under the curve was 0.981, with an optimal cut-off value of 1.14mg/L. For this cut-off point, a sensitivity of 92%, a specificity of 95%, a PPV of 96%, and a NPV of 91% were calculated. The p-βT cut-off point obtained for 100% NPV was 0.64mg/L. Conclusions. β2-Tr and p-βT can be used as CSF fistula markers, since both proteins have high sensitivity and specificity diagnostic values. It is concluded that, ≥ 1.14mg/L p-βT values are indicative of CSF fistula, and values ≤ 0.64mg/L rules it out. Values>0.64 and<1.14mg/L are not conclusive, and in these cases it would be necessary to determine β2-Tr (AU)

Subarachnoid-pleural fistula in an infant treated with mechanical positive-pressure ventilation.

OBJECTIVE: To report a pediatric case of subarachnoid-pleural fistula, its diagnosis, and its treatment. DESIGN: Case report. SETTING: Pediatric intensive care unit. PATIENT: A 9-month-old boy, presenting with severe pleural effusion after posterior chest wall surgery. INTERVENTIONS: Subarachnoid-pleural fistula was confirmed by isolating beta2-transferrin in the pleural fluid and with magnetic resonance cisternography revealing the location. The patient had a healthy outcome, and the fistula dried without surgery, using positive-pressure ventilation and a chest drain. CONCLUSIONS: We used beta2-transferrin to confirm the diagnosis of clinically suspected subarachnoid-pleural fistula. High-resolution computed tomographic and magnetic resonance cisternography are the best techniques to localize the fistula. The currently recommended treatment is surgery; we suggest that bilevel positive-pressure ventilation, especially with noninvasive techniques, could be a treatment alternative, reducing the flow of cerebral spinal fluid through the fistula and allowing spontaneous closure.