We present the clinical case of a 76-year-old woman with delirium causedby multiple factors, including pneumonia. Although this type of case is quitecommon in clinical practice, it provides us with an opportunity to discusslaboratory testing in this context, with a special focus on the role of C-reactiveprotein (CRP). We present data regarding the requests for determination ofserum CRP levels at the University of São Paulo University Hospital overthe past few years. We also present a review of the medical literature on thetopic, as well as clinical epidemiology concepts related to the impact that CRPtesting has on the medical decision-making process
