Perspectives

Don't Order a Test Just Because You Can

Authors: Benjamin T. Galen, MD, Robert L. Fogerty, MD, MPH, Manisha Juthani-Mehta, MD

Abstract

Community-acquired pneumonia (CAP) is a clinical diagnosis based on typical features, including fever, cough with sputum production, and pleuritic chest pain, supported by physical examination findings of lung consolidation, laboratory evidence of leukocytosis or bandemia, and new infiltrates on chest imaging.1 Urinary antigen tests for Legionella pneumophila serotype 1 and Streptococcus pneumoniae are used frequently in the inpatient evaluation of patients with suspected CAP.2,3 These urinary antigen assays have the advantage of being obtained noninvasively and with rapid results; however, given their widespread availability and ease of acquisition, these molecular tests run the risk of being overused at a cost that potentially outweighs their benefit. As with all diagnostic tests, providers should be aware of disease prevalence and test characteristics when ordering and interpreting urinary pneumonia antigen tests. Careful consideration of the limited impact that these assays have in the management of routine cases of CAP also may prevent overuse.

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