El valor de proteínas de fase aguda y la prueba LightCycler® SeptiFast en el diagnóstico de infecciones bacterianas y virales en niños / The value of acute phase reactants and LightCycler® SeptiFast test in the diagnosis of bacterial and viral infections in pediatric patients

Introducción. Evaluamos el nivel de reactantes de fase aguda y la prueba LightCycler® SeptiFast para diferenciar infecciones bacterianas vs.virales. Métodos. Estudio prospectivo en niños febriles. Se analizaron recuento de leucocitos, proteína C-reactiva y procalcitonina en días 1, 3 y 7 de hospitalización. El día 1 se realizaron hemocultivo y radiografía de tórax. Se evaluaron dos grupos de niños que presentaron infecciones bacterianas o virales. Resultados. Se incluyeron 94 niños febriles. La temperatura media de la fiebre fue significativamente más alta en niños con infecciones bacterianas que con infecciones virales (p < 0,001). En 34 (72,3%) niños con infecciones bacterianas, el hemocultivo fue negativo. De ellos, 12 (35,2%) presentaron prueba SeptiFast positiva. No hubo resultados positivos en hemocultivos de niños con infecciones virales y todos tuvieron resultado negativo para la prueba SeptiFast. La media de proteína C-reactiva el primer día de hospitalización fue significativamente más alta en el grupo con infecciones bacterianas (p < 0,001) y en los días 3 y 7 junto con la procalcitonina fueron significativamente más altas en niños con infecciones bacterianas (p <0,001). La sensibilidad y especificidad de los leucocitos, la proteína C-reactiva y la procalcitonina fueron 63,8%, 44,7%, 74,5% y 78,7%, 68,1% y 100%, respectivamente. Las áreas bajo la curva de los leucocitos, la proteína C-reactiva y la procalcitonina fueron 0,519, 0,764 y 0,835, respectivamente. Conclusiones. Los reactantes de fase aguda, en especial procalcitonina, y la prueba LightCycler® SeptiFast podrían ayudar a diferenciar infecciones bacterianas de virales.

Introduction: This study was performed to investigate the value of acute phase reactants and LightCycler® SeptiFast test to differentiate bacterial and viral infections. Population and methods: Children with fever were enrolled to this prospective study. Peripheral white blood cell (WBC), C-reactive protein (CRP) and procalcitonin (PCT) were studied from all patients on day 1, 3 and 7. Blood culture and chest X-ray were also obtained on day 1. Blood samples for LightCycler® SeptiFast test were obtained in all patients to use them if there was uncertain diagnosis between bacterial or viral infection. The patients were divided into two groups as bacterial and viral infection. Results: A total of 94 children with fever were enrolled. The mean value of fever was significantly higher in bacterial group than viral group (p <0.001). In bacterial infection group, 34 (72.3%) patients had negative blood culture. Of those, 12 (35.2%) had positive SeptiFast test. There were no positive blood culture in patients with viral infection group and all of them had negative SeptiFast test. The mean levels of CRP on the first day of admission were significantly higher in bacterial group than viral group (p <0.001). CRP and PCT levels of day 3 and 7 were significantly higher in bacterial group (p <0.001). The sensitivity and specificity levels of WBC, CRP and PCT were 63.8%, 44.7%, 74.5% and 78.7% ,68.1% and 100%, respectively. Conclusions: We found that acute phase reactants, especially PCT, and LightCycler® SeptiFast test may help to differentiate bacterial and viral infections.

Clinical Efficacy Evaluation of Multi-parameter Real-time Polymerase Chain Reaction for the Central Venous Catheter-related Blood Stream Infection / 감염과화학요법

BACKGROUND: The study evaluated the clinical efficacy of a multi-parameter real-time polymerase chain reaction (PCR) test for patients with central venous catheter-related bloodstream infection (CRBSI). MATERIALS AND METHODS: Thirty five patients suspected to have CRBSI were enrolled. The SeptiFast(TM) (SF) multi-parameter real-time PCR test (Roche Diagnostics, Germany) and blood culture were performed and results were compared. RESULTS: The turn-around time for the SF test and blood culture was 32.6+/-28.9 hours and 115.8+/-23.5 hours, respectively. Among the 70 blood samples, the positive rates of SF test and blood culture were 34.3% and 27.1%, respectively, and the agreement rate was 62.9%. Gram-positive bacteria were detected in 10 patients with blood culture and 11 patients with SF test. Gram-negative bacteria were detected in one patient with a blood culture and in seven patients with SF test. Candida was not detected in blood culture but was detected in two patients by the SF test. CONCLUSIONS: SF test was faster and more sensitive for the detection of blood pathogens than blood culture. It provides a more sensitive detection of gram-negative and Candida in blood than does blood culture testing.