Characteristics and outcome of ill critical patients with influenza A infection

To describe all patients admitted to Tunisian intensive care unit with a diagnosis of influenza A/H1N1 virus infection after the 2009 influenza pandemic and to analyse their characteristics, predictors of complications and outcome.

All patients with influenza > 18-years-old hospitalized to the ICU department of Tunisian University hospital of Sousse, between December 1, 2009 and March 31, 2016, with a positive influenza A/H1N1/09 reverse transcriptase polymerase chain reaction (RT-PCR) from a nasopharyngeal specimen were included, were included.

40 cases were admitted to intensive care units. During the reporting period, 22 deaths in intensive care units (55%) were reported, the median age was 53 years (IQR 37-61), 24 (61%) were male, The median scores SAPS II and SOFA were respectively 29 (IQR 23-36) and 6 (IQR 3-10), 27% had chronic obstructive pulmonary disease (COPD), 33.3% diabetic and no patients were vaccinated against influenza A. The cause of admission was in 72.5% of the cases was hypoxemic pneumonae. By using a logistic regression, we found after adjustment to age, that acute respiratory distress syndrome (ARDS) (OR = 27; 95%CI: 3.62-203.78) was the only factor significantly associated with severe outcomes of the cases.

Patients in the first post pandemic season were significantly older and more frequently had underlying medical conditions. Multivariate analysis showed that older male patients with chronic lung disease were at increased risk for a severe clinical outcome.