Etiología bacteriana de la otitis media aguda en España en la era de la vacuna neumocócica conjugada / Bacterial etiology of acute otitis media in Spain in the post-pneumococcal conjugate vaccine era

INTRODUCCIÓN: La otitis media aguda (OMA) es común en niños menores de 3 años. En España hay disponible una vacuna neumocócica conjugada (VNC) (VNC7; Prevenar (Pearl River, NY), Pfizer/Wyeth, EE. UU.) desde 2001, habiéndose alcanzado una cobertura vacunal del 50-60% en niños menores de 5 años. MATERIALES Y MÉTODOS: Se reclutó a niños de 3 a 36 meses con OMA confirmada por especialista en otorrinolaringología en 7 centros españoles (febrero 2009-mayo 2012) (Proyecto GSK: 111425). Se obtuvieron muestras de exudado del oído medio mediante timpanocentesis o de otorrea espontánea, y se hizo cultivo para identificación bacteriana. En muestras con cultivos negativos se realizó análisis adicional mediante reacción en cadena de la polimerasa (PCR). RESULTADOS: De 125 episodios de OMA confirmados en 124 niños, se analizaron 117 (edad mediana: 17 meses [rango: 3-35]); 8 episodios de OMA fueron excluidos del análisis. En total, combinando resultados de cultivo y PCR, se identificaron uno o más patógenos bacterianos en el 69% (81/117) de los episodios; identificándose Haemophilus influenzae (Hi) en el 44% (52/117) y Streptococcus pneumoniae (Spn) en el 39% (46/117). En 77 de los 117 episodios se hizo cultivo para uno o más patógenos, resultando positivo en 63, con mayor frecuencia para Spn (24/77; 31%) e Hi (32/77; 42%). La PCR en episodios con cultivos negativos detectó Hi en el 48% y Spn en el 55% de las muestras. El serotipo de Spn más común fue el 19F (4/24; 17%) seguido del 19A (3/24; 13%); todos los episodios en los que se identificó Hi correspondieron a Hi no tipificable (HiNT). Un total de 81/117 episodios de OMA (69%) se presentaron en niños que habían recibido una o más dosis de vacuna antineumocócica. CONCLUSIONES: HiNT y Spn resultaron ser los principales agentes etiológicos de la OMA en España. Para conocer el impacto de la vacunación antineumocócica en la OMA en España harán falta estudios adicionales cuando se haya alcanzado un nivel de cobertura mayor

INTRODUCTION: Acute otitis media (AOM) is common in children aged <3 years. A pneumococcal conjugate vaccine (PCV) (PCV7; Prevenar, Pfizer/Wyeth, USA) has been available in Spain since 2001, which has a coverage rate of 50-60% in children aged <5 years. MATERIALS AND METHODS: Children aged greater than or equal to 3 to 36 months with AOM confirmed by an ear-nose-throat specialist were enrolled at seven centers in Spain (February 2009-May 2012) (GSK study identifier: 111425). Middle-ear-fluid samples were collected by tympanocentesis or spontaneous otorrhea and cultured for bacterial identification. Culture-negative samples were further analyzed using polymerase chain reaction (PCR). RESULTS: Of 125 confirmed AOM episodes in 124 children, 117 were analyzed (median age: 17 months (range: 3-35); eight AOM episodes were excluded from analyses. Overall, 69% (81/117) episodes were combined culture- and PCR-positive for greater than or equal to 1 bacterial pathogen; 44% (52/117) and 39% (46/117) were positive for Haemophilus influenzae (Hi) and Streptococcus pneumoniae(Spn), respectively. 77 of 117 episodes were cultured for greater than or equal to 1 bacteria, of which 63 were culture-positive; most commonly Spn (24/77; 31%) and Hi (32/77; 42%). PCR on culture-negative episodes identified 48% Hi- and 55% Spn-positive episodes. The most common Spn serotype was 19F (4/24; 17%) followed by 19A (3/24; 13%); all Hi-positive episodes were non-typeable (NTHi). 81/117 AOM episodes (69%) occurred in children who had received greater than or equal to 1 pneumococcal vaccine dose. CONCLUSIONS: NTHi and Spn were the main etiological agents for AOM in Spain. Impact of pneumococcal vaccination on AOM requires further evaluation in Spain, after higher vaccination coverage rate is reached

[Bacterial etiology of acute otitis media in Spain in the post-pneumococcal conjugate vaccine era]. / Etiología bacteriana de la otitis media aguda en España en la era de la vacuna neumocócica conjugada.

INTRODUCTION: Acute otitis media (AOM) is common in children aged <3 years. A pneumococcal conjugate vaccine (PCV) (PCV7; Prevenar, Pfizer/Wyeth, USA) has been available in Spain since 2001, which has a coverage rate of 50-60% in children aged <5 years. MATERIALS AND METHODS: Children aged ≥3 to 36 months with AOM confirmed by an ear-nose-throat specialist were enrolled at seven centers in Spain (February 2009-May 2012) (GSK study identifier: 111425). Middle-ear-fluid samples were collected by tympanocentesis or spontaneous otorrhea and cultured for bacterial identification. Culture-negative samples were further analyzed using polymerase chain reaction (PCR). RESULTS: Of 125 confirmed AOM episodes in 124 children, 117 were analyzed (median age: 17 months (range: 3-35); eight AOM episodes were excluded from analyses. Overall, 69% (81/117) episodes were combined culture- and PCR-positive for ≥1 bacterial pathogen; 44% (52/117) and 39% (46/117) were positive for Haemophilus influenzae (Hi) and Streptococcus pneumoniae (Spn), respectively. 77 of 117 episodes were cultured for ≥1 bacteria, of which 63 were culture-positive; most commonly Spn (24/77; 31%) and Hi (32/77; 42%). PCR on culture-negative episodes identified 48% Hi- and 55% Spn-positive episodes. The most common Spn serotype was 19F (4/24; 17%) followed by 19A (3/24; 13%); all Hi-positive episodes were non-typeable (NTHi). 81/117 AOM episodes (69%) occurred in children who had received ≥1 pneumococcal vaccine dose. CONCLUSIONS: NTHi and Spn were the main etiological agents for AOM in Spain. Impact of pneumococcal vaccination on AOM requires further evaluation in Spain, after higher vaccination coverage rate is reached.