Semi-quantitative procalcitonin assay in critically ill patients with respiratory infections

Abstract

Background: Serum procalcitonin level has been considered prognostic during sepsis and septic shock. We investigated the significance of procalcitonin in critically ill patients with respiratory infections. Methods: The patients who had radiographically diagnosed diffuse lung infiltrations were enrolled on a prospective basis. Bronchoalveolar lavage (BAL) fluid for the purpose of quantitative cultures (≥104 cfu/mL) was obtained from all patients. Serum procalcitonin levels determined by PCT-Q kit were measured on BAL day and classified as follows; <0.5 ng/mL, 0.5-2.0 ng/mL, 2.0-10.0 ng/mL and >10.0 ng/mL. We analyzed the patient's characteristics according to outcome; favorable or unfavorable, defined as death. Results: Patients from the following categories were included: medical 17 (47.2%), surgical 9 (25%), and burned 10 (27.8%). APACHE II scores on admission to intensive care unit were 11.5±6.89 and 11 (30.6%) had unfavorable outcomes. A procalcitonin level ≥0.5 ng/mL was in 17 (47.2%) of all. On univariate analysis, the frequencies of burn injury, mechanical ventilation, multiple organ failure, and a procalcitonin level ≥0.5 ng/mL were more often increased in patients with unfavorable outcomes than in those with favorable outcomes (p