Protective mechanical ventilation in suspected influenza infection

Treatment with lipoxin A 4 improves influenza A infection outcome through macrophage reprogramming, anti-inflammatory and pro-resolutive responses

Objective and design

Here, we evaluated whether a synthetic lipoxin mimetic, designated AT-01-KG, would improve the course of influenza A infection in a murine model.

Treatment

Mice were infected with influenza A/H1N1 and treated with AT-01-KG (1.7 mg/kg/day, i.p.) at day 3 post-infection.

Methods

Mortality rate was assessed up to day 21 and inflammatory parameters were assessed at days 5 and 7.

Results

AT-01-KG attenuated mortality, reducing leukocyte infiltration and lung damage at day 5 and day 7 post-infection. AT-01-KG is a Formyl Peptide Receptor 2 (designated FPR2/3 in mice) agonist, and the protective responses were not observed in FPR2/3 -/- animals. In mice treated with LXA4 (50mg/kg/day, i.p., days 3-6 post-infection), at day 7, macrophage reprogramming was observed, as seen by a decrease in classically activated macrophages and an increase in alternatively activated macrophages in the lungs. Furthermore, the number of apoptotic cells and cells undergoing efferocytosis was increased in the lavage of treated mice. Treatment also modulated the adaptive immune response, increasing the number of anti-inflammatory T cells (Th2) and regulatory T (Tregs) cells in the lungs of the treated mice.

Conclusions

Therefore, treatment with a lipoxin A4 analog was beneficial in a model of influenza A infection in mice. The drug decreased inflammation and promoted resolution and beneficial immune responses, suggesting it may be useful in patients with severe influenza.

Characteristics and Results of Hospital Admission Caused by Influenza Virus Infections in Children under 5 Years Old

AIMS

The influenza virus is an infectious disease with acute respiratory tract infections, caused secondary bacterial infections and death. In this study, we aimed to determine which predictors were associated with the need for high-flow nasal cannula oxygen therapy (HFNC) and transition to intensive care for influenza virus and also to compare single viral pathogens with multiple ones.

METHODS

Inpatients under the age of 5 with influenza virus-related respiratory tract infections between November 2015 and March 2019 were included in the study. Demographic features, comorbidities, symptoms, secondary bacterial infection, need for HFNC and pediatric intensive care unit and respiratory support system, length of hospital stay, polymerase chain reaction tests were recorded.

RESULTS

A total of 93 patients were included in the study. It was determined that 53.8% of the cases were male and 84.9% were under the age of 2. Comorbidities were present in 50.5% of the cases. Secondary bacterial pneumonia developed in 56.9% of the cases. Patients with secondary bacterial pneumonia had higher PICU need, HFNC need and hospital stay (p = 0.014, p ≤ 0.001 and p ≤ 0.001, respectively). Patients with comorbidity had longer hospital stays and a higher need for HFNC (p ≤ 0.001 and p = 0.001, respectively).

CONCLUSIONS

In this study, it was determined that especially comorbidity and secondary bacterial infection aggravated the clinical treatment of hospitalized patients. Therefore, it was concluded that patients with comorbidity should be followed closely and secondary bacterial pneumonia should be recognized and treated early.