Del Rosal, TeresaBaquero-Artigao, FernandoCalvo, CristinaMellado, María JMolina, Juan CSantos, María del MarCilleruelo, María JoséBueno, MercedesStorch de Gracia, PilarTerol, CovadongaRoa, Miguel ÁPiñeiro, RoiGarcía López-Hortelano, MilagrosGarcía-García, María LuzRodríguez, SoniaPenín, MaríaZarauza, AlejandroAlvarado, Franciscode Blas, AnaOtheo, EnriqueRodríguez, AlfonsoHerreros, María LTagarro, AlfredoGrande, LuisRamos, José TomásMaté, IreneMuñoz, CristinaZafra, Miguel ÁRomero-Gómez, María PPérez-Fernández, EliaDelgado, AlbertoCasas Flecha, InmaculadaCabezas, María E2021-04-292021-04-292011-11Influenza Other Respir Viruses. 2011;5(6):e544-51.http://hdl.handle.net/20.500.12105/12822Objective: To describe the epidemiological and clinical characteristics of children hospitalized with 2009 pandemic influenza (pH1N1) in Madrid, Spain. Patients/methods: We included patients less than 14 years of age admitted to one of 18 hospitals in Madrid, Spain, between May 1 and November 30, 2009 and diagnosed with pH1N1 by polymerase chain reaction. A retrospective chart review was conducted and data were compared by age, presence of high-risk medical conditions, and pediatric intensive care unit (PICU) admission. Results: A total of 517 pH1N1 cases were included for final analysis. One hundred and forty-two patients (27·5%) had predisposing underlying illnesses, with immunosuppression (36 children, 7%) and moderate persistent asthma (34, 6·6%) being the most common ones. Patients with underlying medical conditions had longer hospital stays [median 5, interquartile range (IQR) 3-8 days, versus median 4, IQR 3-6, P < 0·001] and required intensive care (20·4% versus 5·9%, P < 0·001) and mechanical ventilation more frequently than previously healthy children. Globally, intensive care was required for 51 patients (10%) and invasive mechanical ventilation for 12 (2%). Pediatric intensive care unit admission was significantly associated with abnormal initial chest X-ray [Odds Ratio (OR) 3·5, 95% confidence interval (CI) 1·5-8·5], underlying neurological condition (OR 3·1, CI 1·2-7·5) and immunosuppression (OR 2·9, 1·2-6·8). Five patients (0·9%) died; two with severe neurological disease, two with leukemia, and one with a malignant solid tumor. Conclusions: Children with underlying medical conditions experienced more severe pH1N1 disease. Risk factors for admission to the PICU included underlying neurological conditions, immunosuppression and abnormal initial chest X-ray.engVoRhttp://creativecommons.org/licenses/by/3.0/2009 pandemic influenza A (H1N1)HospitalizationsPediatric influenzaPH1N1PandemicsAdolescentChildChild, PreschoolFemaleHospitalizationHumansInfantInfluenza A Virus, H1N1 SubtypeInfluenza, HumanIntensive Care Units, PediatricMaleRetrospective StudiesSpainAtribución 3.02178128556e544-5110.1111/j.1750-2659.2011.00272.x1750-2659Influenza and Other Respiratory Virusesopen access