Delay in diagnosis of influenza A (H1N1)pdm09 virus infection in critically ill patients and impact on clinical outcome

• DOI: 10.1186/s13054-016-1512-1
• Publication Date: 2016-10-17T16:02:52Z
• Authors: Francisco Álvarez...; Judith Marín-Corral; Clara Vila; Joan Ramón Masclans; Francisco Javier ...; Ignacio Martín Lo...; Sandra Barbadillo; Alejandro Rodríguez
• Keywords: Adult; Male; Delayed Diagnosis; Critical Illness; 610; Critical Care and Intensive Care Medicine; Influenzavirus; Statistics, Nonparametric; 03 medical and health sciences; Influenza A Virus, H1N1 Subtype; 0302 clinical medicine; Diagnòstic; Risk Factors; 616; Diagnosis; Influenza, Human; Odds Ratio; Influenza viruses; Humans; Hospital Mortality; Prospective Studies; Mortality; Critically ill; Outcome; Aged; Chi-Square Distribution; Research; Length of Stay; Middle Aged; Influenza A (H1N1)pdm09 virus infection; Early diagnosis; Late diagnosis; 3. Good health; Intensive Care Units; Logistic Models; Spain; ICU; Female

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.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.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).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.