DiagNostic Study of Low-dose CT and multipleX PCR on Antibiotic Treatment and Outcome of Community-Acquired Pneumonia

Rationale: Uncertainty in the clinical and etiological diagnosis of community-acquired pneumonia (CAP) often leads to incorrect treatment and unnecessary use of broad-spectrum antibiotics. Establishing the clinical diagnosis of CAP is hampered by the suboptimal sensitivity of chest radiograph to detect pulmonary infiltrates (\~70%). Establishing the etiological diagnosis is also hampered, mainly because of the inevitable diagnostic delays and low sensitivity of routine microbiological tests. There are currently no recommendations for low-dose chest computed tomography (low-dose CT) or viral and bacterial point-of-care multiplex polymerase chain reaction (PoC-PCR) in the diagnostic work-up of CAP patients, because the data supporting such an approach are lacking. Objective: The aim of this study is to determine the added value of low-dose CT and PoC-PCR in the diagnostic workup of patients with CAP hospitalised to non-intensive care unit (ICU) wards in minimizing selective antibiotic pressure while maintaining patient safety. Study design: Cluster-randomised controlled trial with historical control period. Study population: Adult patients (\>=18 years old) with a clinical diagnosis of CAP requiring hospitalisation to a non-ICU ward. Intervention: Intervention arm 1: availability of PoC-PCR during the ER visit; intervention arm 2: performing low-dose CT from the ER or at least within 24 hours; control arm: standard care. Main study parameters/endpoints: The primary effectiveness outcome is days of therapy of broad-spectrum antibiotics. The primary safety outcome, on which the sample size is calculated, is 90-day all-cause mortality. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: There are no risks associated with performing the PoC-PCR and the radiation of the low-dose CT is of negligible risk. Nasopharyngeal swab collection causes a temporary unpleasant sensation. The low-dose CT can reveal unexpected fi