Is procalcitonin evaluation effective in reducing mortality and time receiving antimicrobial therapy in adults with sepsis?
Sepsis is defined as confirmed or suspected infection associated with a systemic inflammatory response syndrome (SIRS). This condition can evolve to an acute organ dysfunction, known as 'severe sepsis'; or to persistent hypotension, even after adequate fluid replacement, known as 'septic shock'. Procalcitonin (PCT) is a biological indicator in the blood that has been found to increase during blood infection. We wanted to assess whether evaluation of PCT can reduce mortality and time receiving antimicrobial therapy in adults with blood infection. To this end, we compared PCT versus nothing, versus standard care (only usual clinical judgement) and versus other blood chemical indicators. Nowadays, other chemical indicators include C-reactive protein (CRP), interleukins and neopterin.
The evidence is current to July 2015. However, we reran the search in October 2016 and will incorporate the three studies of interest when we update the review. For this version, we included 10 studies in this review. These studies were carried out in Australia, Brazil, China, Czech Republic, France, Germany, Indonesia and Switzerland. Researchers evaluated participants from academic and non-academic surgical, general and trauma intensive care units (ICUs) and emergency departments. All studies analysed adults with confirmed or presumed blood infection. Comparisons were most commonly based on ‘standard care’, but one trial used CRP-guided antibiotic therapy. In six trials, study authors had worked as consultants for, and/or received payments from, companies involved in the procalcitonin analysis.
Results showed no significant differences in mortality at longest follow-up (124/573; 21.6% versus 152/583; 26.1%), at 28 days (37/160; 23.1% versus 39/156; 25%), at ICU discharge (28/247; 11.3% versus 25/259; 9.6%) or at hospital discharge (82/398; 20.6% versus 81/407; 19.9%), respectively, for PCT and non-PCT groups. Also, researchers found no differences in mechanical ventilation, clinical severity, reinfection or duration of antimicrobial therapy. No study provided information about participants for whom the antimicrobial regimen was changed from a broad to a narrower spectrum.
Quality of the evidence
We considered the body of available evidence as having very low to moderate quality owing to absence of methods to prevent errors during studies or absence of information about such methods, as well as possibly insufficient numbers of studies and patients per outcome. Additionally, the authors of most studies worked as consultants and/or received payments from companies involved in the procalcitonin analysis.
Up-to-date evidence of very low to moderate quality, with insufficient sample power per outcome, does not clearly support the use of procalcitonin-guided antimicrobial therapy to minimize mortality, mechanical ventilation, clinical severity, reinfection or duration of antimicrobial therapy of patients with septic conditions.
Serum procalcitonin (PCT) evaluation has been proposed for early diagnosis and accurate staging and to guide decisions regarding patients with sepsis, severe sepsis and septic shock, with possible reduction in mortality.
To assess the effectiveness and safety of serum PCT evaluation for reducing mortality and duration of antimicrobial therapy in adults with sepsis, severe sepsis or septic shock.
We searched the Central Register of Controlled Trials (CENTRAL; 2015, Issue 7); MEDLINE (1950 to July 2015); Embase (Ovid SP, 1980 to July 2015); Latin American Caribbean Health Sciences Literature (LILACS via BIREME, 1982 to July 2015); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; EBSCO host, 1982 to July 2015), and trial registers (ISRCTN registry, ClinicalTrials.gov and CenterWatch, to July 2015). We reran the search in October 2016. We added three studies of interest to a list of ‘Studies awaiting classification' and will incorporate these into formal review findings during the review update.
We included only randomized controlled trials (RCTs) testing PCT-guided decisions in at least one of the comparison arms for adults (≥ 18 years old) with sepsis, severe sepsis or septic shock, according to international definitions and irrespective of the setting.
Two review authors extracted study data and assessed the methodological quality of included studies. We conducted meta-analysis with random-effects models for the following primary outcomes: mortality and time spent receiving antimicrobial therapy in hospital and in the intensive care unit (ICU), as well as time spent on mechanical ventilation and change in antimicrobial regimen from a broad to a narrower spectrum.
We included 10 trials with 1215 participants. Low-quality evidence showed no significant differences in mortality at longest follow-up (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.65 to 1.01; I2 = 10%; 10 trials; N = 1156), at 28 days (RR 0.89, 95% CI 0.61 to 1.31; I2 = 0%; four trials; N = 316), at ICU discharge (RR 1.03, 95% CI 0.50 to 2.11; I2 = 49%; three trials; N = 506) and at hospital discharge (RR 0.98, 95% CI 0.75 to 1.27; I2 = 0%; seven trials; N = 805; moderate-quality evidence). However, mean time receiving antimicrobial therapy in the intervention groups was -1.28 days (95% CI to -1.95 to -0.61; I2 = 86%; four trials; N = 313; very low-quality evidence). No primary study has analysed the change in antimicrobial regimen from a broad to a narrower spectrum.