|| Checking for direct PDF access through Ovid
The aim of this study was to evaluate procalcitonin as an adjunct to diagnose bacterial infections in older patients. One hundred seventy-two patients admitted to an acute-care geriatric unit during a 6-month period were prospectively included, 39 of them with an invasive bacterial infection. The best cut-off value to rule in a bacterial infection was 0.51 μg/l with sensitivity 64% and specificity 94%. The best cut-off value to rule out a bacterial infection was 0.08 μg/l with sensitivity 97% and specificity 20%. Procalcitonin was inconclusive (between 0.08 and 0.51 μg/l) for 112 admissions. Procalcitonin over 0.51 μg/l was useless 22 times out of 33 (infection already ruled in on clinical grounds) and misleading in eight of the 11 remaining cases (no infection). Procalcitonin below 0.08 μg/l was useless 23 times out of 27 (infection already ruled out on clinical grounds) and misleading in one of the four remaining cases (infection). Despite a good overall diagnostic accuracy, the clinical usefulness of PCT to diagnose invasive bacterial infections in elderly patients hospitalized in an acute geriatric ward appears to be very limited.