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 24 h 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.