Procalcitonin Testing May Shorten Antibiotic Course in ICU Patients

Anthony J. Brown, MD

June 19, 2009

June 19, 2009 — Monitoring circulating levels of procalcitonin can reduce the duration of antibiotic therapy in intensive care patients without adversely affecting clinical outcomes, according to study findings published in the June 3rd issue of Critical Care.

"Among a large array of laboratory variables, procalcitonin has emerged as the leading one to indicate systemic infections with high accuracy," senior author Dr. Stefan Schroeder, from West Coast Hospital, Heide, Germany, told Reuters Health.

"There is extensive clinical evidence that procalcitonin allows reliable differentiation between systemic inflammatory response syndrome and bacterial or fungal sepsis and closely correlates with the systemic severity of infections in various diseases and medical disciplines," he added. "Moreover, some recent clinical studies have also shown that procalcitonin is a reliable means to guide antibiotic therapy in community acquired pneumonia and sepsis."

The goal of the present study was to determine if a procalcitonin-based algorithm could be used to guide antibiotic therapy in intensive care patients. Included in the investigation were 110 surgical intensive care patients who were receiving antibiotic therapy for confirmed or suspected high-grade bacterial infections. All of the subjects met at least two standard criteria for a systemic inflammatory response syndrome.

The subjects were randomized to receive antibiotic therapy for 8 consecutive days or as dictated by procalcitonin levels. In the procalcitonin group, if a patient had clinical improvements in signs and symptoms and if the procalcitonin level fell below 1 ng/mL or dropped by 25% to 35% from the initial value over 3 days, then antibiotic therapy could be discontinued.

The duration of antibiotic therapy was reduced by 2 days, on average, in the procalcitonin group compared to controls: 5.9 vs. 7.9 days (p < 0.001). Moreover, the results showed that the clinical outcomes of the procalcitonin group were at least as good as those of the control group.

"Beyond a reduction of the length of antibiotic treatment, procalcitonin-guidance also had a favorable effect on the length of the intensive care stay," Dr. Schroeder said. The average length of stay was 15.5 days in the procalcitonin group compared with 17.7 days in the control group (p = 0.046).

The results clearly show that a procalcitonin-guided algorithm is a helpful approach to reduce the length of antibiotic therapy without negatively influencing the outcome of surgical intensive care patients, Dr. Schroeder said.

"Monitoring of procalcitonin is a valuable tool for therapeutic decision-making concerning the length of antibiotic treatment," he added. "However, adequate interpretation of procalcitonin concentrations always requires the background of clinical course and symptoms. This concept contributes to less extensive antibiotic treatment with positive effects on economical factors and the development of drug-resistances in intensive care medicine."

Regarding future research, Dr. Schroeder said that "our procalcitonin-based algorithm is certainly practicable and simple. However, procalcitonin cut-off points for antibiotic termination have not uniquely defined. Thus, procalcitonin-controlled antibiotic therapy must still be tested in heterogenous groups of patients, particularly the safety."

Crit Care. 2009;13:R83.

Reuters Health Information 2009. © 2009 Reuters Ltd.