The Significance of Procalcitonin and C-Reactive Protein in Diagnostic Tests for Respiratory Adenovirus Infections in Children

Background: This study aims to answer the question if procalcitonin tests allow distinguishing bacterial from AdV infections in cases in which acute phase values are significantly elevated. Methods: 40 patients of infant and toddler age were divided into two patient groups (n = 23) and (n = 17) for comparison based on PCT 0.5 μg/L. AdV was determined by polymerase-chain-reaction. Results: The PCT value in Group 1 is 0.21 ± 0.12 μg/L, median 0.2, and 1.56 ± 1.07 μg/L, median 1.3 (p = 0.0001) in Group 2. At a cut-off value of <0.5 μg/L, C-reactive protein, leucocytes, age, fever temperature, and the duration of fever did not differ significantly. This conclusion also applies to a PCT value to <0.9 μg/L. Conclusions: In AdV infections, CRP values of >40 mg/L are observed in more than 80% of patients. A clinically relevant conclusion of our findings is that independent of CRP levels antibiotic therapy is not indicated up to PCT levels of 0.5 μg/l.