[Viral respiratory co-infections in pediatric patients admitted for acute respiratory infection and their impact on clinical severity]. / Co-infección viral respiratoria en niños hospitalizados por infección respiratoria aguda y su impacto en la gravedad clínica.

INTRODUCTION: Respiratory viruses are the leading cause of acute respiratory tract infection (ARI) in children. It has been reported that viral respiratory co-infection could be associated with severe clinical course. OBJECTIVES: To describe the frequency of viral co-infection in children admitted for AlRI and evaluate whether this co-infection was associated with more severe clinical course. PATIENTS AND METHODS: Prospective, descriptive study in pediatric patients who were hospitalized for ARI, with molecular detection of at least 1 respiratory virus in nasopharyngeal sample studied by PCR-Microarray for 17 respiratory viruses. RESULTS: 110 out of 147 patients with detection of > 1 respiratory virus were included. Viral co-infection was detected in 41/110 (37%). 22/110 children (20%) were classified as moderate to severe clinical course and 88/110 (80%) were classified as mild clinical course. In the group of moderate to severe clinical course, viral respiratory co-infection was detected in 6/22 (27.3%), compared to 35/88 (39.8 %) in the mild clinical course group. No statistically significant difference was found regarding the presence of co-infection between groups (p = 0.33). CONCLUSIONS: We detected high rates of viral co-infection in children with ARI. It was not possible to demonstrate that viral co-infections were related with severe clinical course in hospitalized children.

PCA3 sensitivity and specificity for prostate cancer detection in patients with abnormal PSA and/or suspicious digital rectal examination. First Latin American experience.

INTRODUCTION: Prostate Cancer Gene 3 (PCA3) is a recently described and highly specific urinary marker for prostate cancer (CaP). Its introduction in clinical practice to supplement low specificity of prostate specific antigen (PSA) can improve CaP diagnosis and follow-up. However, before its introduction, it is necessary to validate the method of PCA3 detection in distinct geographic populations. OBJECTIVES: Our aim was to describe for the first time in Latin America, the application of the PROGENSA PCA3 assay for PCA3 detection in urine in Chilean men and its utility for CaP diagnosis in men with an indication of prostate biopsy. MATERIALS AND METHODS: Sixty-four Chilean patients (mean age, 64 years) with indication of prostate biopsy because of elevated PSA and/or suspicious digital rectal examination (DRE) were prospectively recruited. PCA3 scores were assessed from urine samples obtained after DRE, before biopsy, and compared with PSA levels and biopsy outcome. RESULTS: The median PSA value and mean PCA3 score were 5.8 ng/ml and 31.7, respectively. Using a cutoff PCA3 score of 35, the sensitivity and specificity for detecting CaP were 52% and 87%, respectively. The receiver operating characteristic (ROC) curve analysis showed an area under the curve of 0.77 for PCA3 and 0.57 for PSA, for the same group of patients. In patients with previous negative biopsy, PCA3 specificity increased by 2.2%. CONCLUSIONS: This is the first report in Latin America on the use of PCA3 in diagnosing CaP. Our results are comparable to those reported in other populations in the literature, demonstrating the reproducibility of the test. PCA3 score was highly specific and we specially recommend its use in patients with persistent elevated PSA and prior negative biopsies.

Frequency and clinical outcome of respiratory viral infections and mixed viral-bacterial infections in children with cancer, fever and neutropenia.

BACKGROUND: The role of respiratory viral infections (RVIs) as a cause of overall fever and neutropenia (FN) episodes in children with cancer has been less characterized than bacterial infections. We conducted a study aimed to determine the frequency of RVI in children with low compared with high risk for invasive bacterial infection (IBI) FN episodes and compare the clinical outcome of RVI and mixed RV-bacterial infections. METHODS: Prospective, multicenter study in children with cancer and FN admitted to pediatric hospitals in Chile between May 2009 and January 2011. Children were evaluated by clinical examination and laboratory tests, including bacterial cultures and their risk for IBI. Nasopharyngeal sample was obtained for the detection of 17 respiratory viruses using polymerase chain reaction-DNA microarray platform. RESULTS: A total of 331 episodes of FN in 193 children were enrolled of whom 55% were male, with the median age of 7 years and 61% had a hematological malignancy. A viral and/or bacterial pathogen was detected in 67% (224/331) episodes. Overall, RVIs were associated with 57% of FN of which one-third were mixed RV-bacterial infections. Bacterial infection was detected in 29% (97/331). Children classified at admission as high risk for IBI had a similar overall proportion of RVI compared with low-risk group. Respiratory syncytial virus (31%) and rhinovirus (23%) were the most frequently detected respiratory viruses, followed by parainfluenza (12%) and influenza A (11%). Children detected with any respiratory virus had fewer days of hospitalization and a significantly lower probability of hypotension and admission to pediatric intensive care unit irrespective of their risk classification status at admission when compared with children with mixed RV-bacterial or bacterial infections (P < 0.05). All children with a sole RVI had favorable outcome. CONCLUSIONS: RVIs were the most frequently detected agents irrespective of their initial risk assessment for IBI. The clinical outcome of mixed RVI was similar to sole RVI episodes as well as for bacterial infections compared with mixed viral-bacterial infections. Systematic and early detection of RVI in children with cancer and FN might help to optimize their management by reducing hospitalization and antimicrobial use.

Co-infección viral respiratoria en niños hospitalizados por infección respiratoria aguda y su impacto en la gravedad clínica / Viral respiratory co-infections in pediatric patients admitted for acute respiratory infection and their impact on clinical severity

Introduction: Respiratory viruses are the leading cause of acute respiratory tract infection (ARI) in children. It has been reported that viral respiratory co-infection could be associated with severe clinical course. Objectives: To describe the frequency of viral co-infection in children admitted for AlRI and evaluate whether this co-infection was associated with more severe clinical course. Patients and Methods: Prospective, descriptive study in pediatric patients who were hospitalized for ARI, with molecular detection of at least 1 respiratory virus in nasopharyngeal sample studied by PCR-Microarray for 17 respiratory viruses. Results: 110 out of 147 patients with detection of > 1 respiratory virus were included. Viral co-infection was detected in 41/110 (37%). 22/110 children (20%) were classified as moderate to severe clinical course and 88/110 (80%) were classified as mild clinical course. In the group of moderate to severe clinical course, viral respiratory co-infection was detected in 6/22 (27.3%), compared to 35/88 (39.8 %) in the mild clinical course group. No statistically significant difference was found regarding the presence of co-infection between groups (p = 0.33). Conclusions: We detected high rates of viral co-infection in children with ARI. It was not possible to demonstrate that viral co-infections were related with severe clinical course in hospitalized children.

Introducción: Los virus respiratorios son la principal causa de infección aguda del tracto respiratorio (IRA) en pediatría. Se ha descrito que la co-infección viral podría relacionarse con infecciones virales respiratorias de curso más grave. Objetivo: Describir la frecuencia de co-infección viral en niños hospitalizados por IRA y determinar si esta co-infección se relacionó con una evolución clínica más grave. Pacientes y Métodos: Estudio descriptivo, prospectivo, en pacientes pediátricos hospitalizados por IRA entre junio y agosto 2010, que tuvieron detección molecular de al menos un virus respiratorio en muestra nasofaríngea estudiada por RPC-microarreglo para 17 virus respiratorios. Resultados: Se incluyeron 110 de 147 pacientes con detección de > 1 virus respiratorio. Se detectó co-infección viral en 41/110 (37%). En cuanto a evolución clínica, 22/110 niños (20%) se clasificaron como evolución moderada a grave (MG) y 88/110 (80%) se clasificaron como evolución leve (L). En el grupo MG se detectó co-infección viral respiratoria en 6/22 (27,3%), mientras que en el grupo L se detectó co-infección en 35/88 (39,8%). No se encontró diferencia significativa en relación a la presencia de co-infección entre ambos grupos (p = 0,33). Conclusión: Se demostró la presencia de co-infección viral en un alto porcentaje de niños con IRA. No fue posible demostrar que la presencia de coinfección viral tenga relación con una evolución clínica más grave en estos niños hospitalizados.