Acute-Phase Reactants in Operatively Treated Upper Extremity Infections: A Retrospective Review.

Background: There are limited data on the use of acute-phase markers in the diagnosis of upper extremity infections. The goal of this study was to determine the percentage of patients with elevated white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) in the setting of an upper extremity infection requiring operative debridement. Methods: In a retrospective review over 12 years, 61 patients who met the inclusion criteria were identified. Results: C-reactive protein was the most sensitive test in the detection of culture-positive infection compared with ESR and WBC (P < .001, P < .0001, respectively). Ninety percent of patients (55 of 61) presented with an abnormal CRP value. The WBC count and ESR were abnormal in 54% and 67% of our cohort, respectively. Conclusions: C-reactive protein is the most sensitive laboratory test when evaluating upper extremity infections that necessitate debridement. The WBC count and ESR should be interpreted with caution and can be normal even in the presence of an infection.