[Pertussis predictors in hospitalized infants with acute lower respiratory tract infection]. / Predictores de coqueluche al ingreso en lactantes hospitalizados con infección respiratoria aguda baja.

BACKGROUND: Pertussis, or whooping cough, caused by Bordetella pertussis (BP) is a re-emerging problem in our environment. Although generally considered that the disease is relatively easy to identify infections respiratory syncytial virus (RSV) can present with similar symptoms in infants remains difficult discrimination. OBJECTIVE: Compare clinical symptoms at admission and complementary studies in infants hospitalized with acute respiratory infection (ARI) and RSV by BP to establish markers that enable their early clinical prediction. MATERIALS AND METHODS: Observational, analytical, case-crossover cross comparing younger than 6 months hospitalized with suspected IRA and pertussis (2007-2012) in which BP identified (PCR and culture) and / or VRS (immunofluorescence in nasal secretions). Coinfections were excluded. Bivariate analysis was performed by calculating OR with 95% CI. Were considered significant at p <0.05. The variables studied were age, sex, hits cough, cyanosis, vomiting, apnea, wheezing and CBC with differential RESULTS: We included 174 infants, 72 (41%) BP and 102 (59%) VRS. Age 2 ± 1 months (range :1-6). In both groups was documented cough and wheeze (OR: 1.2 (0.9 to 1.5) p: 0.1 and OR = 0.9 (0.8 to 1.06) p: 0.2, respectively ). Cyanosis (87% vs. 6%, OR: 14.8 p <0.01), apnea (38% vs. 3%, OR: 13.4 p <0.01) and vomiting (26% vs. 5% , OR: 3.4 p <0.01) were more frequent in infants with BP. The absolute lymphocyte count was significantly higher in children with BP (9387 ± 6317 vs. 5127 ± 2766, p <0.01). By ROC curve was identified at 9000 cells / ml as the best point to differentiate VSR BP (AUC = 0.73, 95% CI :0,64-0, 81). CONCLUSIONS: In infants under 6 months with IRA income presence of apnea, cyanosis and lymphocytosis allowing predict significantly differentiate between pertussis those with RSV infections.

Antecedentes. La tos ferina o coqueluche, producida por Bordetella pertussis (BP) representa un problema re-emergente en nuestro medio. Aunque suele considerarse que la enfermedad es relativamente fácil de identificar, las infecciones por Virus Respiratorio Sincicial (VRS) pueden presentarse con síntomas similares en los lactantes siendo difícil su discriminación. Objetivo. Comparar síntomas clínicos y estudios complementarios al ingreso en lactantes hospitalizados con infección respiratoria aguda (IRA) por BP y por VSR a fin de establecer marcadores que posibiliten su predicción clínica temprana. Material y método. Estudio observacional, analítico, transversal de casos cruzados, comparando menores de 6 meses internados por IRA y sospecha de coqueluche (2007-2012) en los que se identificó BP (PCR y cultivo) y/o VRS (inmunofluorescencia en secreciones nasales); se excluyeron los pacientes con coinfecciones. Se realizó un análisis bivariado mediante el cálculo de OR con IC95%. Se consideró significativo un valor de p<0,05. Las variables en estudio fueron: edad, sexo, tos en accesos, cianosis, vómitos, apneas, sibilancias y hemograma completo con fórmula leucocitaria Resultados. Se incluyeron 174 lactantes; 72 (41%) BP y 102 (59%) VRS. Edad 2±1 mes (Rango:1-6). En ambos grupos se documentó tos y sibilancias (OR:1,2 (0,9-1,5) p:0,1 y OR:0,9 (0,8-1,06) p:0,2, respectivamente). Cianosis (87% vs. 6%;OR:14,8 p<0,01), apnea (38% vs. 3%;OR:13,4 p<0,01) y vómitos (26% vs. 5%;OR:3,4 p<0,01) fueron más frecuentes en lactantes con BP. El recuento absoluto de linfocitos fue significativamente mayor en niños con BP (9387±6317 vs. 5127±2766;p<0,01). Por curva ROC se identificó a 9000 cel/ml como el mejor punto para diferenciar BP de VSR (abc= 0,73; IC95%:0,64-0,81). Conclusiones. En lactantes menores de 6 meses con IRA la presencia al ingreso de apnea, cianosis y linfocitosis predicen significativamente coqueluche permitiendo diferenciarlos de aquellos con infecciones por VRS.

Predictores de coqueluche al ingreso en lactantes hospitalizados con infección respiratoria aguda baja / [Pertussis predictors in hospitalized infants with acute lower respiratory tract infection].

BACKGROUND: Pertussis, or whooping cough, caused by Bordetella pertussis (BP) is a re-emerging problem in our environment. Although generally considered that the disease is relatively easy to identify infections respiratory syncytial virus (RSV) can present with similar symptoms in infants remains difficult discrimination. OBJECTIVE: Compare clinical symptoms at admission and complementary studies in infants hospitalized with acute respiratory infection (ARI) and RSV by BP to establish markers that enable their early clinical prediction. MATERIALS AND METHODS: Observational, analytical, case-crossover cross comparing younger than 6 months hospitalized with suspected IRA and pertussis (2007-2012) in which BP identified (PCR and culture) and / or VRS (immunofluorescence in nasal secretions). Coinfections were excluded. Bivariate analysis was performed by calculating OR with 95

CI. Were considered significant at p <0.05. The variables studied were age, sex, hits cough, cyanosis, vomiting, apnea, wheezing and CBC with differential RESULTS: We included 174 infants, 72 (41

) BP and 102 (59

) VRS. Age 2 ± 1 months (range :1-6). In both groups was documented cough and wheeze (OR: 1.2 (0.9 to 1.5) p: 0.1 and OR = 0.9 (0.8 to 1.06) p: 0.2, respectively ). Cyanosis (87

, OR: 13.4 p <0.01) and vomiting (26

, OR: 3.4 p <0.01) were more frequent in infants with BP. The absolute lymphocyte count was significantly higher in children with BP (9387 ± 6317 vs. 5127 ± 2766, p <0.01). By ROC curve was identified at 9000 cells / ml as the best point to differentiate VSR BP (AUC = 0.73, 95

CI :0,64-0, 81). CONCLUSIONS: In infants under 6 months with IRA income presence of apnea, cyanosis and lymphocytosis allowing predict significantly differentiate between pertussis those with RSV infections.

Predictores de coqueluche al ingreso en lactantes hospitalizados con infección respiratoria aguda baja. / [Pertussis predictors in hospitalized infants with acute lower respiratory tract infection].

BACKGROUND: Pertussis, or whooping cough, caused by Bordetella pertussis (BP) is a re-emerging problem in our environment. Although generally considered that the disease is relatively easy to identify infections respiratory syncytial virus (RSV) can present with similar symptoms in infants remains difficult discrimination. OBJECTIVE: Compare clinical symptoms at admission and complementary studies in infants hospitalized with acute respiratory infection (ARI) and RSV by BP to establish markers that enable their early clinical prediction. MATERIALS AND METHODS: Observational, analytical, case-crossover cross comparing younger than 6 months hospitalized with suspected IRA and pertussis (2007-2012) in which BP identified (PCR and culture) and / or VRS (immunofluorescence in nasal secretions). Coinfections were excluded. Bivariate analysis was performed by calculating OR with 95

CI. Were considered significant at p <0.05. The variables studied were age, sex, hits cough, cyanosis, vomiting, apnea, wheezing and CBC with differential RESULTS: We included 174 infants, 72 (41

) BP and 102 (59

) VRS. Age 2 ± 1 months (range :1-6). In both groups was documented cough and wheeze (OR: 1.2 (0.9 to 1.5) p: 0.1 and OR = 0.9 (0.8 to 1.06) p: 0.2, respectively ). Cyanosis (87

vs. 6

, OR: 14.8 p <0.01), apnea (38

vs. 3

, OR: 13.4 p <0.01) and vomiting (26

vs. 5

, OR: 3.4 p <0.01) were more frequent in infants with BP. The absolute lymphocyte count was significantly higher in children with BP (9387 ± 6317 vs. 5127 ± 2766, p <0.01). By ROC curve was identified at 9000 cells / ml as the best point to differentiate VSR BP (AUC = 0.73, 95

CI :0,64-0, 81). CONCLUSIONS: In infants under 6 months with IRA income presence of apnea, cyanosis and lymphocytosis allowing predict significantly differentiate between pertussis those with RSV infections.