Utility of basic clinical and laboratory parameters to predict Serious Bacterial Infection in children younger than 3 months old hospitalized for Febrile Syndrome without Source. / Utilidad de los parámetros clínicos y de laboratorio básicos para predecir infección bacteriana seria en menores de 3 meses que se hospitalizan por síndrome febril sin foco.

INTRODUCTION: In 20% of children with febrile syndrome, it appears as fever of unknown origin (FUO) syndrome. Management strategies in this group have high sensitivity but low specificity. OBJECTIVES: To cha racterize serious bacterial infections (SBI) in children younger than three months old hospitalized because of FUO syndrome and to evaluate the utility of clinical and laboratory parameters in the identification of patients that are at high risk of SBI. PATIENTS AND METHOD: Prospective study in patients aged < 3 months hospitalized due to FUO syndrome between January 2014 and November 2015 in two pediatric hospitals in the Metropolitan Region. INCLUSION CRITERIA: age 4 days - 3 months, fever > 38°C longer than 72 hours after onset without demonstrable cause. EXCLUSION CRITERIA: anti microbial use up to 7 days before admission, preterm infants < 34 weeks, birth weight < 2 kg, and im munocompromised. Demographic, clinical, and laboratory tests data were recorded as well as blood count and CRP, discharge diagnosis, and ruled out, probable or confirmed SBI. RESULTS: 32% of the patients were discharged with diagnosis of SBI, 28% with diagnosis of viral or probably viral infec tion, 34% with diagnosis of not specified FUO syndrome, and 6% due to other causes. There were no significant differences in the CRP value, altered WBCs count, toxic aspect, or hours of fever at the admission when comparing groups with and without SBI (p < 0.05). The combination of clinical and laboratory parameters showed 27% of sensitivity, 90% of specificity, 60% of PPV, and 71% of NPV. CONCLUSION: It was not possible to establish clinical and laboratory parameters that allow the identifi cation of children younger than 3 months old at high risk of SBI, however, they maintain their value as low risk indicators. It is necessary further investigation of other clinical and laboratory elements that allow discriminating SBI from viral infections.

Utilidad de los parámetros clínicos y de laboratorio básicos para predecir infección bacteriana seria en menores de 3 meses que se hospitalizan por síndrome febril sin foco / Utility of basic clinical and laboratory parameters to predict Serious Bacterial Infection in children younger than 3 months old hospitalized for Febrile Syndrome without Source

Resumen: Introducción: Un 20% de los niños con síndrome febril se presenta como síndrome febril sin foco (SFSF). Las es trategias de manejo en este grupo presentan alta sensibilidad, pero baja especificidad. Objetivos: Ca racterizar las infecciones bacterianas serias (IBS) en menores de 3 meses hospitalizados por SFSF, y evaluar utilidad de parámetros clínicos y de laboratorio en la identificación de pacientes con alto riesgo de IBS. Pacientes y Método: Estudio prospectivo en pacientes < 3 meses hospitalizados entre enero 2014 y noviembre 2015 por SFSF en dos hospitales pediátricos de la Región Metropolitana. Criterios de inclusión: edad 4 días - 3 meses, fiebre > 38°C de < 72 h de evolución sin causa demostra ble. Criterios de exclusión: uso de antimicrobianos hasta 7 días previo a su ingreso, prematuros < 34 semanas, peso de nacimiento < 2 kg e inmunocomprometidos. Se registraron datos demográficos, clínicos, y exámenes de laboratorio, hemograma y PCR, diagnóstico de egreso, IBS descartada, IBS probable o confirmada. Resultados: 32% de los pacientes egresó con diagnóstico de IBS, 28% con diagnóstico de infección viral o probablemente viral, 34% con diagnóstico de SFSF no especificado y 6% SFSF por otras causas. No se encontraron diferencias significativas en PCR, leucocitosis, aspecto tóxico ni horas de fiebre al ingreso al comparar los grupos con y sin IBS (p > 0,05). La combinación de parámetros clínicos y de laboratorio mostro sensibilidad de 27%, especificidad de 90%, VPP 60% y VPN 71%. Conclusión: No fue posible establecer que parámetros clínicos y de laboratorio permitan identificar menores de 3 meses con alto riesgo de IBS, manteniendo su utilidad como indicadores de bajo riesgo. Es necesario contar con otros elementos clínicos y de laboratorio que permitan discrimi nar IBS de infecciones virales.

Abstract: Introduction: In 20% of children with febrile syndrome, it appears as fever of unknown origin (FUO) syndrome. Management strategies in this group have high sensitivity but low specificity. Objectives: To cha racterize serious bacterial infections (SBI) in children younger than three months old hospitalized because of FUO syndrome and to evaluate the utility of clinical and laboratory parameters in the identification of patients that are at high risk of SBI. Patients and Method: Prospective study in patients aged < 3 months hospitalized due to FUO syndrome between January 2014 and November 2015 in two pediatric hospitals in the Metropolitan Region. Inclusion criteria: age 4 days - 3 months, fever > 38°C longer than 72 hours after onset without demonstrable cause. Exclusion criteria: anti microbial use up to 7 days before admission, preterm infants < 34 weeks, birth weight < 2 kg, and im munocompromised. Demographic, clinical, and laboratory tests data were recorded as well as blood count and CRP, discharge diagnosis, and ruled out, probable or confirmed SBI. Results: 32% of the patients were discharged with diagnosis of SBI, 28% with diagnosis of viral or probably viral infec tion, 34% with diagnosis of not specified FUO syndrome, and 6% due to other causes. There were no significant differences in the CRP value, altered WBCs count, toxic aspect, or hours of fever at the admission when comparing groups with and without SBI (p < 0.05). The combination of clinical and laboratory parameters showed 27% of sensitivity, 90% of specificity, 60% of PPV, and 71% of NPV. Conclusion: It was not possible to establish clinical and laboratory parameters that allow the identifi cation of children younger than 3 months old at high risk of SBI, however, they maintain their value as low risk indicators. It is necessary further investigation of other clinical and laboratory elements that allow discriminating SBI from viral infections.

Etiología de la neumonía adquirida en la comunidad en adultos hospitalizados en Santiago, Chile: implicancias para las guías clínicas / Etiology of community acquired pneumonia requiring hospitalization in Chile: implications for the guidelines

Background: There are a few studies examining the etiology of community acquired pneumonia (CAP) in Chile. Aim: To evaluate the etiology of CAP in hospitalized adults. Method: We prospectively studied 130 patients (mean age +/- SD: 68 +/- 18 y.o.; overall hospital mortality: 6.2 percent), over a 16 month period. Microbiological evaluation included blood and sputum cultures for bacteria; serology for C. pneumoniae, C. psittaci and M. pneumoniae; urine antigen for L. pneumophila; and nasopharyngeal swab for respiratory viruses. Results: Etiology was identified from 64 (49 percent) patients (two or more pathogens in 6). The most frequent microorganisms were S. pneumoniae (34 percent), Parainfluenza types 1 to 3 (22 percent), Influenza A or B (14 percent ), C. pneumoniae (6 percent), M. pneumoniae (6 percent), H. influenzae (5 percent) and S. marcescens (5 percent). Twenty-five of 27 (93 percent) respiratory viruses were identified in autumn or winter. Pneumococcal pneumonia patients (19) compared to those infected with respiratory virus (23) were younger (59 +/- 18 versus 72 +/- 17 y.o.; p = 0.021) and had less comorbidities (47 versus 87 percent; p = 0.0001). No patients with bacteremia (13 of 121: 11 percent) died. Conclusions: S. pneumoniae remains the most important pathogen to cover by initial antibiotic therapy; the second most frequent etiological agents were respiratory viruses followed by "atypical pathogens". Recommendations for the management of patients infected with these two last categories of agents should be included in future national guidelines.

Fundamento: Hay escasos estudios que examinen la etiología de la neumonía adquirida en la comunidad (NAC) en población adulta chilena. Objetivo: Identificar la etiología de la NAC en adultos inmunocompetentes hospitalizados. Método: Estudiamos, prospectiva y consecutivamente durante 16 meses, a 130 pacientes (edad promedio +/ - DS: 68 +/ - 18 años; letalidad en el hospital: 6,2 por ciento). La evaluación microbiológica incluyó cultivo de expectoración y hemocultivos para bacterias; Financiamiento: Fondo de Investigación de la Sociedad Chilena de Enfermedades Respiratorias (2002) y fondo de la Dirección de Investigación de la Pontificia Universidad Católica de Chile (DIPUC 2003/10E). Serología para C. pneumoniae, C. psittaci, M. pneumoniae; antígeno urinario para L. pneumophila e hisopado nasofaríngeo para virus respiratorios. Resultados: Se identificó la etiología en 64 (49 por ciento) pacientes (dos o más patógenos en 6). Los principales microorganismos fueron: S. pneumoniae (34 por ciento), virus Parainfluenza 1 a 3 (22 por ciento), virus Influenza A o B (14 por ciento), C. pneumoniae (6 por ciento), M. pneumoniae (6 por ciento), H. influenzae (5 por ciento) y S. marcescens (5 por ciento). El 93 por ciento (25/27) de los virus respiratorios se identificaron en otoño-invierno. Los pacientes con neumonía neumocócica (19) comparados con aquéllos infectados por virus respiratorios (23) eran más jóvenes (59 + /- 18 versus 72 +/ - 17 años; p = 0,021) y tenían menos comorbilidades (47 por ciento versus 87 por ciento; p = 0,0001). Ninguno de los 13 (11 por ciento) pacientes con bacteremia falleció en el hospital. Conclusiones: S. pneumoniae sigue siendo el principal patógeno a cubrir por el tratamiento antibiótico empírico; los virus respiratorios y los agentes atípicos fueron los que siguieron en frecuencia. Las futuras guías clínicas nacionales deberían incluir recomendaciones para el manejo de los pacientes infectados por estos dos últimos grupos de...