doi:10.1186/s13054-016-1512-1engÁlvarez-Lerma, F.Marín-Corral, J.Vila, C.Masclans, J.R.González, de MolinaMartín Loeches, I.Barbadillo, S.Rodríguez, A.Cobo, P.Martins, J.Carbayo, C.Robles-Musso, E.Cárdenas, A.Fierro, J.Fernández, D.O.Sierra, R.Huertos, M.J.Pérez, M.L.C.Laderas, J.C.P.Guerrero, R.Robles, J.C.León, M.E.Gómez, A.B.Márquez, E.Rodríguez-Carvajal, M.Estella, Á.Pomares, J.Ballesteros, J.L.Romero, O.M.Fernández, Y.Lobato, F.Prieto, J.F.Albofedo-Sánchez, J.Martínez, P.de, la TorreNieto, M.Sola, E.C.Castellanos, M.Á.D.Soler, G.S.Leyba, C.O.Garnacho-Montero, J.Hinojosa, R.Fernández, E.Loza, A.León, C.López, S.G.Arenzana, Á.Ocaña, D.Navarrete, I.Beryanaki, M.Z.Sánchez, I.Alé, M.P.Brea, A.M.P.Casas, J.F.M.Serón, C.Avellanas, M.L.Lander, A.de Arellano, S.G.R.Marquina Lacueva, M.I.Luque, P.Serrano, E.P.Lázaro, J.F.M.Polo, C.S.Cía, I.G.Bartolomé, B.J.Núñez, C.L.González, I.Marsilla, J.I.T.Andrés, C.J.Ibañes, P.G.Aguilar, P.A.Montón, J.M.Regil, P.D.Iglesias, L.González, C.P.Fernández, B.Q.Iglesias, L.M.Soria, L.V.Escudero, R.Y.Revuelta, M.R.M.Ruiz, J.M.Q.García-Rodríguez, Á.Cuadrado, M.M.Mariño, A.L.B.Socias, L.Ibáñez, P.Borges-Sa, M.Socias, A.Del Castillo, A.Marcos, R.J.Muñoz, C.Goytisolo, J.M.B.Carbonero, J.A.M.Ayestarán, I.López, M.Á.G.Pàmies, C.V.Senoff, R.P.de Medrano, M.G.L.Ruiz-Santana, S.Díaz, J.J.Ramírez, C.S.Sisón, M.Hernández, D.Trujillo, A.Regalado, L.Fernández, S.R.Lorente, L.Rivero, J.C.Quintero, M.L.M.Martín, M.Martínez, S.Cáceres, J.J.Palacio, M.S.Rodríguez, D.G.Leria, M.R.Suberviola, B.Ugarte, P.García-López, F.Iniesta, R.S.Alonso, Á.Á.Padilla, A.Palacios, B.M.Grande, M.L.G.Rodríguez, M.C.M.álvarez, H.A.HCheca, A.A.Hernández, H.M.Albaya, A.Obregón, A.S.Crespo, C.M.Estrella, C.A.Puncel, C.B.Oyargue, E.Q.Canabal, A.Marina, L.de Toro, I.L.Simón, A.Añón, J.M.Pueyo, M.J.L.Ortiz, M.V.Echeverri, S.O.Ferreras, Z.Herraez, J.C.B.Macías, S.Berezo, J.Á.Varela, J.B.Schweizer, P.B.Salamanca, Á.G.Lomas, L.T.Anzález, A.O.ávila, R.C.Pérez G., F.J.Terrero, A.Á.Ezpeleta, F.T.Sala, C.López, O.Páez, Z.García, Á.Ule, D.C.Crespo, M.R.Rebolledo, J.P.Andrés, N.H.Zirena, A.C.C.García, B.R.Messa, J.B.L.Catalán, R.M.Ferrer, M.Torres, A.Cilloniz, C.Ansorregui, S.B.Cabré, L.Baeza, I.Rovira, A.álvarez-Lerma, F.Vázquez, A.Nolla, J.Fernández, F.Cervelló, J.R.Iglesia, R.Mañéz, R.Ballús, J.Granada, R.M.Vallés, J.Díaz, E.Ortíz, M.Guía, C.Martín-Loeches, I.Páez, J.Almirall, J.Balanzó, X.Güell, E.Yébenes, J.C.Rello, J.Arnau, E.Pérez, M.Laborda, C.Souto, J.Lagunes, L.Catalán, I.Sirvent,Delay in diagnosis of influenza A (H1N1)pdm09 virus infection in critically ill patients and impact on clinical outcomeART-2016-97412Background: Patients infected with influenza A (H1N1)pdm09 virus requiring admission to the ICU remain an important source of mortality during the influenza season. The objective of the study was to assess the impact of a delay in diagnosis of community-acquired influenza A (H1N1)pdm09 virus infection on clinical outcome in critically ill patients admitted to the ICU. Methods: A prospective multicenter observational cohort study was based on data from the GETGAG/SEMICYUC registry (2009-2015) collected by 148 Spanish ICUs. All patients admitted to the ICU in which diagnosis of influenza A (H1N1)pdm09 virus infection had been established within the first week of hospitalization were included. Patients were classified into two groups according to the time at which the diagnosis was made: early (within the first 2 days of hospital admission) and late (between the 3rd and 7th day of hospital admission). Factors associated with a delay in diagnosis were assessed by logistic regression analysis. Results: In 2059 ICU patients diagnosed with influenza A (H1N1)pdm09 virus infection within the first 7 days of hospitalization, the diagnosis was established early in 1314 (63.8 %) patients and late in the remaining 745 (36.2 %). Independent variables related to a late diagnosis were: age (odds ratio (OR) = 1.02, 95 % confidence interval (CI) 1.01-1.03, P < 0.001); first seasonal period (2009-2012) (OR = 2.08, 95 % CI 1.64-2.63, P < 0.001); days of hospital stay before ICU admission (OR = 1.26, 95 % CI 1.17-1.35, P < 0.001); mechanical ventilation (OR = 1.58, 95 % CI 1.17-2.13, P = 0.002); and continuous venovenous hemofiltration (OR = 1.54, 95 % CI 1.08-2.18, P = 0.016). The intra-ICU mortality was significantly higher among patients with late diagnosis as compared with early diagnosis (26.9 % vs 17.1 %, P < 0.001). Diagnostic delay was one independent risk factor for mortality (OR = 1.36, 95 % CI 1.03-1.81, P < 0.001). Conclusions: Late diagnosis of community-acquired influenza A (H1N1)pdm09 virus infection is associated with a delay in ICU admission, greater possibilities of respiratory and renal failure, and higher mortality rate. Delay in diagnosis of flu is an independent variable related to death.2016http://zaguan.unizar.es/record/5844110.1186/s13054-016-1512-1http://zaguan.unizar.es/record/58441oai:zaguan.unizar.es:58441Critical care 20, 1 (2016), 337 [11 pp.]byhttp://creativecommons.org/licenses/by/3.0/es/info:eu-repo/semantics/openAccess