Pneumococcal urinary antigen testing for antimicrobial guidance in community-acquired pneumonia–A register-based cohort study

•Routinely performing pneumococcal urinary antigen tests needs to be evalUATed.•Performing urinary antigen test has little effect on antibiotic therapy in pneumonia.•Mild pneumonia with a positive test is less frequently treated with broad-spectrum antibiotics.•Severe pneumonia is treated with broad-spectrum antibiotics regardless of test result. To evaluate the effect of pneumococcal urinary antigen test (UAT) usage on broad-spectrum antibiotic treatment in community-acquired pneumonia (CAP). Patients admitted to 32 Swedish hospitals between 2011 and 2014 were retrospectively included from the Swedish National Quality Register of CAP. Using propensity score matched data, stratified by CRB-65 score, we studied the effect of performing UAT and of positive test results on treatment with broad-spectrum β-lactam monotherapy (BSBM) and antibiotics with coverage for atypical bacteria compared to narrow-spectrum β-lactam monotherapy (NSBM). UAT was performed for 4,995/14,590 (34.2%) patients, 603/4,995 (12.1%) of whom had positive test results. At day three, performing UAT was not associated with decreased use of BSBM (OR 1.07, 95% CI 0.94–1.23) but was associated with increased atypical coverage among patients with CRB-65 score 2 (OR 1.47, 95% CI 1.06–2.02). A positive UAT was associated with decreased BSBM use (OR 0.39, 95% CI 0.25–0.60) and decreased atypical coverage (OR 0.25, 95% CI 0.16–0.37), predominantly in non-severe CAP. At day one, performing UAT was associated with atypical coverage among patients with CRB-65 scores 2 (OR 2.60, 95% CI 1.69–3.98) and 3–4 (OR 3.69, 95% CI 1.55–8.79), and a positive test reduced the odds of BSBM treatment among CRB-65 score 3–4 patients (OR 3.49, 95% CI 1.02–12.0). Performing UAT had no overall effect on decreasing the use of BSBM treatment by day three of hospitalization, yet non-severely ill patients with positive UAT results were less likely to be treated with BSBM and antibiotics with atypical coverage.