Bacterial pneumonia as an influenza complication

The pathogenesis and impact of coinfection, in particular bacterial coinfection, in influenza are incompletely understood. This review summarizes results from studies on bacterial coinfection in the recent pandemic influenza outbreak. Systemic immune mechanisms play a key role in the development of coinfection based on the complexity of the interaction of the host and the viral and bacterial pathogens. Several studies were performed to determine the point prevalence of bacterial coinfection in influenza. Coinfection in influenza is frequent in critically ill patients with Streptococcus pneumoniae being the most frequent bacterial pathogen and higher rates of potentially resistant pathogens over the years. Bacterial pneumonia is certainly an influenza complication. The recent epidemiology findings have helped to partially resolve the contribution of different pathogens. Immunosuppression is a risk factor for bacterial coinfection in influenza, and the epidemiology of coinfection has changed over the years during the last influenza pandemic, and these recent findings should be taken into account during present outbreak

Proven Fatal Invasive Aspergillosis in a Patient with COVID-19 and Staphylococcus aureus Pneumonia

There is increasing attention for opportunistic pathogens such as Aspergillus fumigatus complicating SARS-CoV-2 infections in the critically ill. For invasive fungal disease, establishing a clear diagnosis can be challenging due to the invasiveness of diagnostic procedures required for a proven case. Here we present one of the first proven cases of COVID-19-associated pulmonary aspergillosis by positive culture of post-mortem lung biopsy

Treatment with broadly neutralizing influenza antibodies reduces severity of secondary pneumococcal pneumonia in mice

Secondary bacterial pneumonia is a frequent complication of influenza, associated with high morbidity and mortality. We hypothesized that treatment with neutralizing influenza A antibody AT10_002 protects against severe secondary pneumococcal infection in a mouse model of influenza A infection. Influenza A (H3N2) virus–infected male C57Bl6 mice were treated intravenously with either AT10_002 or a control 2 days postinfection. Seven days later, both groups were infected with Streptococcus pneumoniae and killed 18 hours later. Mice receiving AT10_002 showed less loss of bodyweight compared with controls (+1% vs −12%, P <.001), lower viral loads in bronchoalveolar lavage fluids (BALFs) (7 vs 194 RNA copies per µL; P <.001), and reduced bacterial outgrowth in lung homogenates (3.3 × 101 vs 2.5 × 105 colony-forming units per mg; P <.001). The treatment group showed lower pulmonary wet weights, lower cell counts, and lower protein levels in BALF compared with controls. Treatment with AT10_002 was associated with lower levels of tumor necrosis factor-α, interleukin (IL)-6, cytokine-induced neutrophil chemoattractant (KC), and interferon-γ in BALF and lower IL-6 and KC in lung homogenates. Treatment with anti-influenza antibody AT10_002 is associated with reduced weight loss, viral load, bacterial outgrowth, and lung injury in a murine model of secondary pneumococcal pneumonia following influenza infection

Clinical practice of respiratory virus diagnostics in critically ill patients with a suspected pneumonia : A prospective observational study

BACKGROUND: Clinical guidelines suggest testing for respiratory viruses during the influenza season, but are unclear which categories of patients on the intensive care unit (ICU) should be tested. OBJECTIVE: We described the clinical practice of diagnostic testing for respiratory virus infections in patients presenting to ICU with suspected community-acquired pneumonia (CAP) or hospital-acquired pneumonia (HAP). STUDY DESIGN: Prospective observational study in consecutive CAP and HAP patients with an ICU stay of more than 24h in two tertiary care hospitals in The Netherlands, from 2011 to December 2013. The proportion of patients receiving diagnostic testing with PCR for the presence of respiratory viruses in respiratory tract specimens was determined. RESULTS: In total, 1452 patients were included, of which 712 patients presented with CAP and 740 with HAP. In CAP, 282 of 712 (40%) were tested for respiratory viruses (190 of 417 (46%) during the influenza season). In HAP, 95 of 740 (13%) were tested (50 of 372 (13%) during the influenza season). Regardless of the season, virus diagnostic tests were ordered significantly more often in patients with comorbidities, and in those presenting with elevated CRP and leucopenia. In patients who were tested during the influenza season, the prevalence of influenza was 14% in patients with CAP and 10% in those with HAP. Influenza was absent during the summer in both groups. CONCLUSIONS: Less than half of patients admitted to the ICU with suspected pneumonia were tested for the presence of viral pathogens, either in or outside the influenza season

Respiratory Viruses in Invasively Ventilated Critically Ill Patients-A Prospective Multicenter Observational Study

Objectives: The presence of respiratory viruses and the association with outcomes were assessed in invasively ventilated ICU patients, stratified by admission diagnosis. Design: Prospective observational study. Setting: Five ICUs in the Netherlands. Patients: Between September 1, 2013, and April 30, 2014, 1,407 acutely admitted and invasively ventilated patients were included. Interventions: None. Measurements and Main Results: Nasopharyngeal swabs and tracheobronchial aspirates were collected upon intubation and tested for 14 respiratory viruses. Out of 1,407 patients, 156 were admitted because of a severe acute respiratory infection and 1,251 for other reasons (non-severe acute respiratory infection). Respiratory viruses were detected in 28.8% of severe acute respiratory infection patients and 17.0% in non-severe acute respiratory infection (p < 0.001). In one third, viruses were exclusively detected in tracheobronchial aspirates. Rhinovirus and human metapneumovirus were more prevalent in severe acute respiratory infection patients (9.6% and 2.6% vs 4.5 and 0.2%; p = 0.006 and p < 0.001). In both groups, there were no associations between the presence of viruses and the number of ICU-free days at day 28, crude mortality, and mortality in multivariate regression analyses. Conclusions: Respiratory viruses are frequently detected in acutely admitted and invasively ventilated patients. Rhinovirus and human metapneumovirus are more frequently found in severe acute respiratory infection patients. Detection of respiratory viruses is not associated with worse clinically relevant outcomes in the studied cohort of patients

Respiratory Viruses in Invasively Ventilated Critically Ill Patients-A Prospective Multicenter Observational Study

OBJECTIVES: The presence of respiratory viruses and the association with outcomes were assessed in invasively ventilated ICU patients, stratified by admission diagnosis. DESIGN: Prospective observational study. SETTING: Five ICUs in the Netherlands. PATIENTS: Between September 1, 2013, and April 30, 2014, 1,407 acutely admitted and invasively ventilated patients were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Nasopharyngeal swabs and tracheobronchial aspirates were collected upon intubation and tested for 14 respiratory viruses. Out of 1,407 patients, 156 were admitted because of a severe acute respiratory infection and 1,251 for other reasons (non-severe acute respiratory infection). Respiratory viruses were detected in 28.8% of severe acute respiratory infection patients and 17.0% in non-severe acute respiratory infection (p < 0.001). In one third, viruses were exclusively detected in tracheobronchial aspirates. Rhinovirus and human metapneumovirus were more prevalent in severe acute respiratory infection patients (9.6% and 2.6% vs 4.5 and 0.2%; p = 0.006 and p < 0.001). In both groups, there were no associations between the presence of viruses and the number of ICU-free days at day 28, crude mortality, and mortality in multivariate regression analyses. CONCLUSIONS: Respiratory viruses are frequently detected in acutely admitted and invasively ventilated patients. Rhinovirus and human metapneumovirus are more frequently found in severe acute respiratory infection patients. Detection of respiratory viruses is not associated with worse clinically relevant outcomes in the studied cohort of patients