Effect of Procalcitonin-Guided Treatment in Patients with Infections: a Systematic Review and Meta-Analysis

Risk prediction of biomarkers for early multiple organ dysfunction in critically ill patients

Background

Shock and organ damage occur in critically ill patients in the emergency department because of biological responses to invasion, and cytokines play an important role in their development. It is important to predict early multiple organ dysfunction (MOD) because it is useful in predicting patient outcomes and selecting treatment strategies. This study examined the accuracy of biomarkers, including interleukin (IL)-6, in predicting early MOD in critically ill patients compared with that of quick sequential organ failure assessment (qSOFA).

Methods

This was a multicenter observational sub-study. Five universities from 2016 to 2018. Data of adult patients with systemic inflammatory response syndrome who presented to the emergency department or were admitted to the intensive care unit were prospectively evaluated. qSOFA score and each biomarker (IL-6, IL-8, IL-10, tumor necrosis factor-α, C-reactive protein, and procalcitonin [PCT]) level were assessed on Days 0, 1, and 2. The primary outcome was set as MOD on Day 2, and the area under the curve (AUC) was analyzed to evaluate qSOFA scores and biomarker levels.

Results

Of 199 patients, 38 were excluded and 161 were included. Patients with MOD on Day 2 had significantly higher qSOFA, SOFA, and Acute Physiology and Chronic Health Evaluation II scores and a trend toward worse prognosis, including mortality. The AUC for qSOFA score (Day 0) that predicted MOD (Day 2) was 0.728 (95% confidence interval [CI]: 0.651–0.794). IL-6 (Day 1) showed the highest AUC among all biomarkers (0.790 [95% CI: 0.711–852]). The combination of qSOFA (Day 0) and IL-6 (Day 1) showed improved prediction accuracy (0.842 [95% CI: 0.771–0.893]). The combination model using qSOFA (Day 1) and IL-6 (Day 1) also showed a higher AUC (0.868 [95% CI: 0.799–0.915]). The combination model of IL-8 and PCT also showed a significant improvement in AUC.

Conclusions

The addition of IL-6, IL-8 and PCT to qSOFA scores improved the accuracy of early MOD prediction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-021-00534-z.

Multivariate meta-analysis of critical care meta-analyses: a meta-epidemiological study

Background

Meta-analyses typically consider multiple outcomes and report univariate effect sizes considered as independent. Multivariate meta-analysis (MVMA) incorporates outcome correlation and synthesises direct evidence and related outcome estimates within a single analysis. In a series of meta-analyses from the critically ill literature, the current study contrasts multiple univariate effect estimates and their precision with those derived from MVMA.

Methods

A previous meta-epidemiological study was used to identify meta-analyses with either one or two secondary outcomes providing sufficient detail to structure bivariate or tri-variate MVMA, with mortality as primary outcome. Analysis was performed using a random effects model for both odds ratio (OR) and risk ratio (RR); borrowing of strength (BoS) between multivariate outcome estimates was reported. Estimate comparisons, β coefficients, standard errors (SE) and confidence interval (CI) width, univariate versus multivariate, were performed using Lin’s concordance correlation coefficient (CCC).

Results

In bivariate meta-analyses, for OR (n = 49) and RR (n = 48), there was substantial concordance (≥ 0.69) between estimates; but this was less so for tri-variate meta-analyses for both OR (n = 25; ≥ 0.38) and RR (≥ -0.10; n = 22). A variable change in the multivariate precision of primary mortality outcome estimates compared with univariate was present for both bivariate and tri-variate meta-analyses and for metrics. For second outcomes, precision tended to decrease and CI width increase for bivariate meta-analyses, but was variable in the tri-variate. For third outcomes, precision increased and CI width decreased. In bivariate meta-analyses, OR coefficient significance reversal, univariate versus MVMA, occurred once for mortality and 6 cases for second outcomes. RR coefficient significance reversal occurred in 4 cases; 2 were discordant with OR. For tri-variate OR meta-analyses reversal of coefficient estimate significance occurred in two cases for mortality, nine cases for second and 7 cases for third outcomes. In RR meta-analyses significance reversals occurred for mortality in 2 cases, 6 cases for second and 3 cases for third; there were 7 discordances with OR. BoS was greater in trivariate MVMAs compared with bivariate and for OR versus RR.

Conclusions

MVMA would appear to be the preferred solution to multiple univariate analyses; parameter significance changes may occur. Analytic metric appears to be a determinant.

COVID-19 and Sex Differences: Mechanisms and Biomarkers

Men are consistently overrepresented in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and coronavirus disease 2019 (COVID-19) severe outcomes, including higher fatality rates. These differences are likely due to gender-specific behaviors, genetic and hormonal factors, and sex differences in biological pathways related to SARS-CoV-2 infection. Several social, behavioral, and comorbid factors are implicated in the generally worse outcomes in men compared with women. Underlying biological sex differences and their effects on COVID-19 outcomes, however, have received less attention. The present review summarizes the available literature regarding proposed molecular and cellular markers of COVID-19 infection, their associations with health outcomes, and any reported modification by sex. Biological sex differences characterized by such biomarkers exist within healthy populations and also differ with age- and sex-specific conditions, such as pregnancy and menopause. In the context of COVID-19, descriptive biomarker levels are often reported by sex, but data pertaining to the effect of patient sex on the relationship between biomarkers and COVID-19 disease severity/outcomes are scarce. Such biomarkers may offer plausible explanations for the worse COVID-19 outcomes seen in men. There is the need for larger studies with sex-specific reporting and robust analyses to elucidate how sex modifies cellular and molecular pathways associated with SARS-CoV-2. This will improve interpretation of biomarkers and clinical management of COVID-19 patients by facilitating a personalized medical approach to risk stratification, prevention, and treatment.

Procalcitonin-guided antibiotic therapy in acute exacerbation of chronic obstructive pulmonary disease: An updated meta-analysis

BACKGROUND

The benefit of a procalcitonin (PCT)-guided antibiotic strategy in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) remains uncertain.

OBJECTIVES

This updated meta-analysis was performed to reevaluate the therapeutic potential of PCT-guided antibiotic therapy in AECOPD.

DATA SOURCES

We searched PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov up to February 2019 to identify randomized controlled trials (RCTs) investigating the role of PCT-guided antibiotic strategies in treating adult patients with AECOPD. Relative risk (RR) or mean differences (MD) with accompanying 95% confidence intervals (CIs) were calculated with a random-effects model.

RESULTS

Eight RCTs with a total of 1376 participants were included. The results suggested that a PCT-guided antibiotic strategy reduced antibiotic prescriptions (RR: 0.55; 95% CI: 0.39-0.76; P = .0003). However, antibiotic exposure duration (MD: -1.34; 95% CI: -2.83-0.16; P = .08), antibiotic use after discharge (RR: 1.61; 95% CI: 0.61-4.23; P = .34), clinical success (RR: 1.02; 95% CI: 0.96-1.08; P = .47), all-cause mortality (RR: 1.05; 95% CI: 0.72-1.55; P = .79), exacerbation at follow-up (RR: 0.97; 95% CI: 0.80-1.18; P = .78), readmission at follow-up (RR: 1.12; 95% CI: 0.82-1.53; P = .49), length of hospital stay (MD: -0.36; 95% CI: -1.36-0.64; P = .48), and adverse events (RR: 1.33; 95% CI: 0.79-2.23; P = .28) were similar in both groups.

IMPLICATIONS OF KEY FINDINGS

A PCT-guided antibiotic strategy is associated with fewer antibiotic prescriptions, and has similar efficacy and safety compared with standard antibiotic therapy in AECOPD patients.

Procalcitonin-Guided Antibiotic Discontinuation and Mortality in Critically Ill Adults: A Systematic Review and Meta-analysis

BACKGROUND

Procalcitonin (PCT)-guided antibiotic discontinuation appears to decrease antibiotic use in critically ill patients, but its impact on survival remains less certain.

METHODS

We searched PubMed, Embase, Scopus, Web of Science, and CENTRAL for randomized controlled trials (RCTs) of PCT-guided antibiotic discontinuation in critically ill adults reporting survival or antibiotic duration. Searches were conducted without language restrictions from inception to July 23, 2018. Two reviewers independently conducted all review stages; another adjudicated differences. Data were pooled using random-effects meta-analysis. Study quality was assessed with the Cochrane risk of bias tool, and evidence was graded using GRADEpro.

RESULTS

Among critically ill adults (5,158 randomized; 5,000 analyzed), PCT-guided antibiotic discontinuation was associated with decreased mortality (16 RCTs; risk ratio [RR], 0.89; 95% CI, 0.83-0.97; I2 = 0%; low certainty). Death was the primary outcome in only one study and a survival benefit was not observed in the subset specified as sepsis (10 RCTs; RR, 0.94; 95% CI, 0.85-1.03; I2 = 0%), those without industry sponsorship (nine RCTs; RR, 0.98; 95% CI, 0.87-1.10; I2 = 0%), high PCT-guided algorithm adherence (five RCTs; RR, 0.93; 95% CI, 0.71-1.22; I2 = 0%), and PCT-guided algorithms without C-reactive protein (eight RCTs; RR, 0.96; 95% CI, 0.87-1.06; I2 = 0%). PCT-guided antibiotic discontinuation decreased antibiotic duration (mean difference, 1.31 days; 95% CI, -2.27 to -0.35; I2 = 93%) (low certainty).

CONCLUSIONS

Our findings of increased survival and decreased antibiotic utilization associated with PCT-guided antibiotic discontinuation represent low-certainty evidence with a high risk of bias. This relationship was primarily observed in studies without high protocol adherence and in studies with algorithms combining PCT and C-reactive protein. Properly designed studies with mortality as the primary outcome are needed to address this question.

TRIAL REGISTRY

International Prospective Register of Systematic Reviews (PROSPERO); No.: CRD42016049715; URL: http://www.crd.york.ac.uk/PROSPERO_REBRANDING/display_record.asp?ID=CRD42016049715.

Procalcitonin guidance in patients with lower respiratory tract infections: a systematic review and meta-analysis

Although effective for bacterial lower respiratory tract infections (LRTIs), antibiotic treatment is often incorrectly prescribed for non-bacterial LRTIs. Procalcitonin has emerged as a promising biomarker to diagnose bacterial infections and guide antibiotic treatment decisions. As part of a regulatory submission to the U.S. Food and Drug Administration, this systematic review and meta-analysis summarizes the effects of procalcitonin-guided antibiotic stewardship on antibiotic use and clinical outcomes in adult LRTI patients. PubMed and the Cochrane Database of Systematic Reviews were searched for English-language randomized controlled trials published between January 2004 and May 2016. Random and fixed effects meta-analyses were performed to study efficacy (initiation of antibiotics, antibiotic use) and safety (mortality, length of hospital stay). Eleven trials were retained, comprising 4090 patients. Procalcitonin-guided patients had lower odds of antibiotic initiation (odds ratio: 0.26; 95% confidence interval [CI]: 0.13-0.52) and shorter mean antibiotic use (weighted mean difference: -2.15 days; 95% CI: -3.30 to -0.99) compared to patients treated with standard care. Procalcitonin use had no adverse impact on mortality (relative risk: 0.94; 95% CI: 0.69-1.28) and length of hospital stay (weighted mean difference: -0.15 days; 95% CI: -0.60 to 0.30). Procalcitonin guidance reduces antibiotic initiation and use among adults with LRTIs with no apparent adverse impact on length of hospital stay or mortality.

Diagnostic reliability of the procalcitonin serum marker in septic frail patient

AIM

Aging is associated with increased inflammation, particularly in frailty. Indeed, such patient presents increased serum inflammatory markers, such as C-reactive protein and interleukin-6. Interleukin-6 is an important stimulating factor for the production of procalcitonin. The aim of this study is to evaluate the diagnostic reliability of serum PCT in the diagnosis of sepsis in frail elderly patients.

METHODS

Using Fried's criteria for frailty, 140 older patients hospitalized for any cause were consecutively enrolled and divided in two groups: no-frail (60 patients) and frail (80 patients). Patients were further categorized on the basis of the presence/absence of sepsis. Interleukin-6, procalcitonin and inflammatory indices were sampled at hospital admission.

RESULTS

Septic patients from frail and no-frail groups showed higher values of interleukin-6 and procalcitonin. However, focusing on groups without sepsis, a statistically significant difference of interleukin-6 and procalcitonin values among frail and no-frail groups was seen at the post-hoc analysis. In frail group, procalcitonin cut-off of 0.5 ng/ml had a sensibility and specificity, respectively, of 100 and 22%. Through receiver operating characteristic curve (ROC) analysis, we found that procalcitonin serum value of 1.4 ng/ml had better sensibility and specificity (respectively, 93.8 and 84.4%, AUC 0.965).

CONCLUSIONS

In our study, we confirm the diagnostic reliability of procalcitonin in frail elderly patients for the diagnosis of sepsis. We found that 1.4 ng/ml was the best cut-off in this population.

Significant Publications on Infectious Diseases Pharmacotherapy in 2017

PURPOSE

The most significant peer-reviewed articles pertaining to infectious diseases (ID) pharmacotherapy, as selected by panels of ID pharmacists, are summarized.

SUMMARY

Members of the Houston Infectious Diseases Network (HIDN) were asked to nominate peer-reviewed articles that they believed most contributed to the practice of ID pharmacotherapy in 2017, including the areas of human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). A list of 33 articles related to general ID pharmacotherapy and 4 articles related to HIV/AIDS was compiled. A survey was distributed to members of the Society of Infectious Diseases Pharmacists (SIDP) for the purpose of selecting 10 articles believed to have made the most significant impact on general ID pharmacotherapy and the single significant publication related to HIV/AIDS. Of 524 SIDP members who responded, 221 (42%) and 95 (18%) members voted for general pharmacotherapy- and HIV/AIDS-related articles, respectively. The highest ranked articles are summarized below.

CONCLUSION

Remaining informed on the most significant ID-related publications is a challenge when considering the large number of ID-related articles published annually. This review of significant publications in 2017 may aid in that effort.

Adherence to a procalcitonin-guided antibiotic treatment protocol in patients with severe sepsis and septic shock

Background

In randomised controlled trials, procalcitonin (PCT)-guided antibiotic treatment has been proven to significantly reduce length of antibiotic therapy in intensive care unit (ICU) patients. However, concern was raised on low protocol adherence and high rates of overruling, and thus the value of PCT-guided treatment in real clinical life outside study conditions remains unclear. In this study, adherence to a PCT protocol to guide antibiotic treatment in patients with severe sepsis and septic shock was analysed.

Methods

From 2012 to 2014, surgical ICU patients with severe sepsis or septic shock were retrospectively screened for PCT measurement series appropriate to make treatment decisions on antibiotic therapy. We compared (1) patients with appropriate PCT measurement series to patients without appropriate series; (2) patients who reached the antibiotic stopping advice threshold (PCT < 0.5 ng/mL and/or decrease to 10% of peak level) to patients who did not reach a stopping advice threshold; and (3) patients who were treated adherently to the PCT protocol to non-adherently treated patients. The groups were compared in terms of antibiotic treatment duration, PCT kinetics, and other clinical outcomes.

Results

Of 81 patients with severe sepsis or septic shock, 14 were excluded due to treatment restriction or short course in the ICU. The final analysis was performed on 67 patients. Forty-two patients (62.7%) had appropriate PCT measurement series. In patients with appropriate PCT series, median initial PCT (p = 0.001) and peak PCT levels (p < 0.001) were significantly higher compared to those with non-appropriate series. In 26 patients with appropriate series, PCT levels reached an antibiotic stopping advice. In 8 of 26 patients with stopping advice, antibiotics were discontinued adherently to the PCT protocol (30.8%). Patients with adherently discontinued antibiotics had a shorter antibiotic treatment (7d [IQR 6–9] vs. 12d [IQR 9–16]; p = 0.002). No differences were seen in terms of other clinical outcomes.

Conclusion

In patients with severe sepsis and septic shock, procalcitonin testing was irregular and adherence to a local PCT protocol was low in real clinical life. However, adherently treated patients had a shorter duration of antibiotic treatment without negative clinical outcomes. Procalcitonin peak values and kinetics had a clear impact on the regularity of PCT testing.

Electronic supplementary material

The online version of this article (10.1186/s13613-018-0415-5) contains supplementary material, which is available to authorized users.

Using Procalcitonin in Septic Shock to Guide Antibacterial Therapy

Over the last decade, the biomarkers procalcitonin and C-reactive protein have gained interest in sepsis research. Procalcitonin is a unique biomarker that is specific to bacterial infection and has demonstrated utility in the risk stratification of patients with potential life-threatening bacterial infections. In addition, procalcitonin has been documented as having a role in reducing the rate of unnecessary antibiotics while positively impacting antibiotic resistance rates and cost savings. The purposes of this review article are to discuss the clinical relevance of C-reactive protein and procalcitonin as diagnostic and prognostic markers for sepsis with a focus on the use of serial procalcitonin levels as a component of antibiotic stewardship programs. The federal government has recently become invested in combating the progression of antibiotic resistance; a 5-year national plan has been developed to address these concerns. Establishing a reliable antibiotic stewardship program is one of the goals of this national plan.

Antibiotics for treatment of acute exacerbation of chronic obstructive pulmonary disease: a network meta-analysis

Background

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is the most common reason for the hospitalization and death of pulmonary patients. The use of antibiotics as adjuvant therapy for AECOPD, however, is still a matter of debate.

Methods

In this study, we searched the PubMed, EmBase, and Cochrane databases for randomized controlled trials published until September 2016 that evaluated the use of antibiotics for AECOPD treatment. The major outcome variables were clinical cure rate and adverse effects. The microbiological response rate, relapse of exacerbation, and mortality were also analysed. A random-effect network was used to assess the effectiveness and tolerance of each antibiotic used for AECOPD treatment.

Results

In this meta-analysis, we included 19 articles that assessed 17 types of antibiotics used in 5906 AECOPD patients. The cluster ranking showed that dirithromycin had a high clinical cure rate with a low rate of adverse effects. Ofloxacin, ciprofloxacin, and trimethoprim-sulfamethoxazole had high clinical cure rates with median rates of adverse effects. In terms of the microbiological response rate, only doxycycline was significantly better than placebo (odds ratio (OR), 3.84; 95% confidence interval (CI), 1.96–7.54; p < 0.001). There were no other significant results with respect to the frequency of recurrence or mortality.

Conclusions

Our study indicated that dirithromycin is adequate for improving the clinical cure rate of patients with AECOPD with few adverse effects. Ofloxacin, ciprofloxacin, and trimethoprim-sulfamethoxazole are also recommended for disease treatment. However, caution should still be exercised when using antibiotics to treat AECOPD.

Trial Registration Not applicable.

Electronic supplementary material

The online version of this article (doi: 10.1186/s12890-017-0541-0) contains supplementary material, which is available to authorized users.

Procalcitonin-guided antibiotic therapy in intensive care unit patients: a systematic review and meta-analysis

Background

Serum procalcitonin (PCT) concentration is used to guide antibiotic decisions in choice, timing, and duration of anti-infection therapy to avoid antibiotic overuse. Thus, we performed a systematic review and meta-analysis to seek evidence of different PCT-guided antimicrobial strategies for critically ill patients in terms of predefined clinical outcomes.

Methods

We searched for relevant studies in PubMed, Embase, Web of Knowledge, and the Cochrane Library up to 25 February 2017. Randomized controlled trials (RCTs) were included if they reported data on any of the predefined outcomes in adult ICU patients managed with a PCT-guided algorithm or according to standard care. Results were expressed as risk ratio (RR) or mean difference (MD) with accompanying 95% confidence interval (CI).

Data synthesis

We included 13 trials enrolling 5136 patients. These studies used PCT in three clinical strategies: initiation, discontinuation, or combination of antibiotic initiation and discontinuation strategies. Pooled analysis showed a PCT-guided antibiotic discontinuation strategy had fewer total days with antibiotics (MD − 1.66 days; 95% CI − 2.36 to − 0.96 days), longer antibiotic-free days (MD 2.26 days; 95% CI 1.40–3.12 days), and lower short-term mortality (RR 0.87; 95% CI 0.76–0.98), without adversely affecting other outcomes. Only few studies reported data on other PCT-guided strategies for antibiotic therapies, and the pooled results showed no benefit in the predefined outcomes.

Conclusions

Our meta-analysis produced evidence that among all the PCT-based strategies, only using PCT for antibiotic discontinuation can reduce both antibiotic exposure and short-term mortality in a critical care setting.

Electronic supplementary material

The online version of this article (10.1186/s13613-017-0338-6) contains supplementary material, which is available to authorized users.

The next generation of rapid point-of-care testing identification tools for ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a frequent issue in intensive care units (ICU), with a major impact on morbidity, mortality and cost of care. VAP diagnosis remains challenging: traditional culture-based microbiological techniques are still the gold-standard, but are too slow to enable clinicians to improve prognosis with timely antimicrobial therapy adjustment. Prolonged exposure to inappropriate antibiotics has also been shown to increase the incidence of multi-drug-resistant organisms (MDROs). Point-of-care testing (POCT) tools are diagnostic testing methods that can be used at or near the bedside, with delays ranging from a couple minutes to a few hours. The use of POCTs for VAP could allow for faster diagnosis and antimicrobial therapy adjustments. Despite uncertainty regarding their diagnostic value, C-reactive protein (CRP) and procalcitonin (PCT) can be detected using POCTs in few minutes. In VAP, CRP showed a sensitivity of 56% to 88% and specificity of 86% to 91%; PCT showed a sensitivity of 78% to 100% and a specificity between 75% and 97% using non-POCT methods. Automated microscopy could also be used in clinical ICU setting, with reported sensitivity of 100% and specificity of 97%, allowing for antibiotic susceptibility testing (AST) in less than 12 h. Multiplex polymerase chain reaction (MPCR) could allow for identification and AST approximation through the detection of drug-resistance genes in about 6 h, with reported sensitivity of 89.2% and specificity of 97.1%; although use as POCT was shown to result in test failure in about 40% of samples. Despite being at an early development stage, exhalome analysis, which allows for non-invasive fast identification, and chromogenic tests, more suited for the detection of drug-resistance enzymes, are also promising techniques for POCT diagnosis of VAP.

Procalcitonin to initiate or discontinue antibiotics in acute respiratory tract infections

BACKGROUND

Acute respiratory infections (ARIs) comprise of a large and heterogeneous group of infections including bacterial, viral, and other aetiologies. In recent years, procalcitonin (PCT), a blood marker for bacterial infections, has emerged as a promising tool to improve decisions about antibiotic therapy (PCT-guided antibiotic therapy). Several randomised controlled trials (RCTs) have demonstrated the feasibility of using procalcitonin for starting and stopping antibiotics in different patient populations with ARIs and different settings ranging from primary care settings to emergency departments, hospital wards, and intensive care units. However, the effect of using procalcitonin on clinical outcomes is unclear. This is an update of a Cochrane review and individual participant data meta-analysis first published in 2012 designed to look at the safety of PCT-guided antibiotic stewardship.

OBJECTIVES

The aim of this systematic review based on individual participant data was to assess the safety and efficacy of using procalcitonin for starting or stopping antibiotics over a large range of patients with varying severity of ARIs and from different clinical settings.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE, and Embase, in February 2017, to identify suitable trials. We also searched ClinicalTrials.gov to identify ongoing trials in April 2017.

SELECTION CRITERIA

We included RCTs of adult participants with ARIs who received an antibiotic treatment either based on a procalcitonin algorithm (PCT-guided antibiotic stewardship algorithm) or usual care. We excluded trials if they focused exclusively on children or used procalcitonin for a purpose other than to guide initiation and duration of antibiotic treatment.

DATA COLLECTION AND ANALYSIS

Two teams of review authors independently evaluated the methodology and extracted data from primary studies. The primary endpoints were all-cause mortality and treatment failure at 30 days, for which definitions were harmonised among trials. Secondary endpoints were antibiotic use, antibiotic-related side effects, and length of hospital stay. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using multivariable hierarchical logistic regression adjusted for age, gender, and clinical diagnosis using a fixed-effect model. The different trials were added as random-effects into the model. We conducted sensitivity analyses stratified by clinical setting and type of ARI. We also performed an aggregate data meta-analysis.

MAIN RESULTS

From 32 eligible RCTs including 18 new trials for this 2017 update, we obtained individual participant data from 26 trials including 6708 participants, which we included in the main individual participant data meta-analysis. We did not obtain individual participant data for four trials, and two trials did not include people with confirmed ARIs. According to GRADE, the quality of the evidence was high for the outcomes mortality and antibiotic exposure, and quality was moderate for the outcomes treatment failure and antibiotic-related side effects.Primary endpoints: there were 286 deaths in 3336 procalcitonin-guided participants (8.6%) compared to 336 in 3372 controls (10.0%), resulting in a significantly lower mortality associated with procalcitonin-guided therapy (adjusted OR 0.83, 95% CI 0.70 to 0.99, P = 0.037). We could not estimate mortality in primary care trials because only one death was reported in a control group participant. Treatment failure was not significantly lower in procalcitonin-guided participants (23.0% versus 24.9% in the control group, adjusted OR 0.90, 95% CI 0.80 to 1.01, P = 0.068). Results were similar among subgroups by clinical setting and type of respiratory infection, with no evidence for effect modification (P for interaction > 0.05). Secondary endpoints: procalcitonin guidance was associated with a 2.4-day reduction in antibiotic exposure (5.7 versus 8.1 days, 95% CI -2.71 to -2.15, P < 0.001) and lower risk of antibiotic-related side effects (16.3% versus 22.1%, adjusted OR 0.68, 95% CI 0.57 to 0.82, P < 0.001). Length of hospital stay and intensive care unit stay were similar in both groups. A sensitivity aggregate-data analysis based on all 32 eligible trials showed similar results.

AUTHORS' CONCLUSIONS

This updated meta-analysis of individual participant data from 12 countries shows that the use of procalcitonin to guide initiation and duration of antibiotic treatment results in lower risks of mortality, lower antibiotic consumption, and lower risk for antibiotic-related side effects. Results were similar for different clinical settings and types of ARIs, thus supporting the use of procalcitonin in the context of antibiotic stewardship in people with ARIs. Future high-quality research is needed to confirm the results in immunosuppressed patients and patients with non-respiratory infections.

Strategies to enhance rational use of antibiotics in hospital: a guideline by the German Society for Infectious Diseases

Introduction

In the time of increasing resistance and paucity of new drug development there is a growing need for strategies to enhance rational use of antibiotics in German and Austrian hospitals. An evidence-based guideline on recommendations for implementation of antibiotic stewardship (ABS) programmes was developed by the German Society for Infectious Diseases in association with the following societies, associations and institutions: German Society of Hospital Pharmacists, German Society for Hygiene and Microbiology, Paul Ehrlich Society for Chemotherapy, The Austrian Association of Hospital Pharmacists, Austrian Society for Infectious Diseases and Tropical Medicine, Austrian Society for Antimicrobial Chemotherapy, Robert Koch Institute.

Materials and methods

A structured literature research was performed in the databases EMBASE, BIOSIS, MEDLINE and The Cochrane Library from January 2006 to November 2010 with an update to April 2012 (MEDLINE and The Cochrane Library). The grading of recommendations in relation to their evidence is according to the AWMF Guidance Manual and Rules for Guideline Development.

Conclusion

The guideline provides the grounds for rational use of antibiotics in hospital to counteract antimicrobial resistance and to improve the quality of care of patients with infections by maximising clinical outcomes while minimising toxicity. Requirements for a successful implementation of ABS programmes as well as core and supplemental ABS strategies are outlined. The German version of the guideline was published by the German Association of the Scientific Medical Societies (AWMF) in December 2013.

Effectiveness and safety of procalcitonin evaluation for reducing mortality in adults with sepsis, severe sepsis or septic shock

BACKGROUND

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.

OBJECTIVES

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.

SEARCH METHODS

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.

SELECTION CRITERIA

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.

DATA COLLECTION AND ANALYSIS

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.

MAIN RESULTS

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.

AUTHORS' CONCLUSIONS

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.

Economic evaluation of procalcitonin-guided antibiotic therapy in acute respiratory infections: a Chinese hospital system perspective

Background:

Cost-impact models have indicated that in the USA, the use of antibiotic stewardship protocols based on procalcitonin (PCT) levels for patients with suspected acute respiratory tract infection results in cost savings. Our objective was to assess the cost impact of adopting PCT testing among patients with acute respiratory infections (ARI) from the perspective of a typical hospital system in urban China.

Methods:

To conduct an economic evaluation of PCT testing versus usual care we built a cost-impact model based on a previously published patient-level meta-analysis data of randomized trials including Chinese sites. The data were adapted to the China setting by applying the results to mean lengths of stay, costs, and practice patterns typically found in China. We estimated the annual ARI visit rate for the typical hospital system (assumed to be 1650 beds) and ARI diagnosis.

Results:

In the inpatient setting, the costs of PCT-guided care compared to usual care for a cohort of 16,405 confirmed ARI patients was almost 1.1 million Chinese yuan (CNY), compared to almost 1.8 million CNY for usual care, resulting in net savings of 721,563 CNY to a typical urban Chinese hospital system for 2015. In the ICU and outpatient settings, savings were 250,699 CNY and 2.4 million CNY, respectively. The overall annual net savings of PCT-guided care was nearly 3.4 million CNY.

Conclusions:

Substantial savings are associated with PCT protocols of ARI across common China hospital treatment settings mainly by direct reduction in unnecessary antibiotic utilization.

Diagnostic accuracy of procalcitonin and presepsin for infectious disease in patients with acute kidney injury

Procalcitonin (PCT) and presepsin (PSEP) are sepsis markers, but their diagnostic accuracy may be compromised in acute kidney injury (AKI). We evaluated their diagnostic accuracy in patients with/without AKI. This retrospective study comprised 91 patients with at least one criterion of systematic inflammatory response syndrome. AKI markers plasma neutrophil gelatinase-associated lipocalin (NGAL), plasma cystatin C (CysC), and estimated glomerular filtration rate (eGFR) were measured upon hospital admission and on days 1, 3, 5, and 7. Patients were divided into non-AKI and AKI groups. APACHE II severity scores were determined. PCT and PSEP levels were increased significantly in non-AKI and AKI patients with infection. NGAL, CysC, and eGFR in patients with infection were associated with PCT, PSEP, and APACHE II score, and levels of PCT and PSEP were correlated significantly with disease severity. PCT and PSEP are useful markers of bacterial infections in AKI but different thresholds should be applied.

[Procalcitonin as a tool for the assessment of successful therapy of severe sepsis : An analysis using clinical routine data]

INTRODUCTION

Procalcitonin (PCT) is a well-evaluated biomarker for the detection of severe bacterial infections and monitoring effectiveness of antibiotic therapy. This study aims to evaluate the usefulness of PCT in a clinical routine setting.

MATERIALS AND METHODS

Of 358,763 clinical cases from 7 German hospitals in 2012 and 2013, 3854 cases had an ICD-10 code representing sepsis. A total of 1778 cases had pathologic PCT and one episode of infection. Of those, 671 showed a series of measures that was suitable to assess treatment success using PCT reduction. Propensity score matching was used to create two comparable groups with 211 patients in each group.

RESULTS

The group with PCT reduction within 12 days showed a highly significant better proportion of survival (146/211 vs. 17/211; p < 0.0001). The odds ratio for death according to PCT reduction vs. nonreduction is 25.64 (p < 0.0001; 95 % CI: 14.49-45.45). PCT was normalized after an average of 6.2 days.

DISCUSSION

The difference in survival implicates that PCT reduction is a suitable surrogate parameter to indicate successful antimicrobial therapy. Successful antibiotic therapy is a proven predictor for survival in sepsis. This study also showed concordant results in the group of patients with sepsis after abdominal surgery. Results from subgroup analyses confirm the initial findings. PCT reduction was used as surrogate for therapy success, as the antimicrobial therapy was not electronically available.

CONCLUSION

PCT reduction is a strong predictor for survival. However, the data show that overall use of PCT to monitor sepsis therapy is not yet routinely established. Hospitals should establish algorithms for sepsis treatment that include PCT for the assessment of adequacy and the monitoring of success of the antimicrobial therapy.

Procalcitonin testing to guide antibiotic therapy for the treatment of sepsis in intensive care settings and for suspected bacterial infection in emergency department settings: a systematic review and cost-effectiveness analysis

BACKGROUND

Determination of the presence or absence of bacterial infection is important to guide appropriate therapy and reduce antibiotic exposure. Procalcitonin (PCT) is an inflammatory marker that has been suggested as a marker for bacterial infection.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of adding PCT testing to the information used to guide antibiotic therapy in adults and children (1) with confirmed or highly suspected sepsis in intensive care and (2) presenting to the emergency department (ED) with suspected bacterial infection.

METHODS

Twelve databases were searched to June 2014. Randomised controlled trials were assessed for quality using the Cochrane Risk of Bias tool. Summary relative risks (RRs) and weighted mean differences (WMDs) were estimated using random-effects models. Heterogeneity was assessed visually using forest plots and statistically using the I (2) and Q statistics and investigated through subgroup analysis. The cost-effectiveness of PCT testing in addition to current clinical practice was compared with current clinical practice using a decision tree with a 6 months' time horizon.

RESULTS

Eighteen studies (36 reports) were included in the systematic review. PCT algorithms were associated with reduced antibiotic duration [WMD -3.19 days, 95% confidence interval (CI) -5.44 to -0.95 days, I (2) = 95.2%; four studies], hospital stay (WMD -3.85 days, 95% CI -6.78 to -0.92 days, I (2) = 75.2%; four studies) and a trend towards reduced intensive care unit (ICU) stay (WMD -2.03 days, 95% CI -4.19 to 0.13 days, I (2) = 81.0%; four studies). There were no differences for adverse clinical outcomes. PCT algorithms were associated with a reduction in the proportion of adults (RR 0.77, 95% CI 0.68 to 0.87; seven studies) and children (RR 0.86, 95% CI 0.80 to 0.93) receiving antibiotics, reduced antibiotic duration (two studies). There were no differences for adverse clinical outcomes. All but one of the studies in the ED were conducted in people presenting with respiratory symptoms. Cost-effectiveness: the base-case analyses indicated that PCT testing was cost-saving for (1) adults with confirmed or highly suspected sepsis in an ICU setting; (2) adults with suspected bacterial infection presenting to the ED; and (3) children with suspected bacterial infection presenting to the ED. Cost-savings ranged from £368 to £3268. Moreover, PCT-guided treatment resulted in a small quality-adjusted life-year (QALY) gain (ranging between < 0.001 and 0.005). Cost-effectiveness acceptability curves showed that PCT-guided treatment has a probability of ≥ 84% of being cost-effective for all settings and populations considered (at willingness-to-pay thresholds of £20,000 and £30,000 per QALY).

CONCLUSIONS

The limited available data suggest that PCT testing may be effective and cost-effective when used to guide discontinuation of antibiotics in adults being treated for suspected or confirmed sepsis in ICU settings and initiation of antibiotics in adults presenting to the ED with respiratory symptoms and suspected bacterial infection. However, it is not clear that observed costs and effects are directly attributable to PCT testing, are generalisable outside people presenting with respiratory symptoms (for the ED setting) and would be reproducible in the UK NHS. Further studies are needed to assess the effectiveness of adding PCT algorithms to the information used to guide antibiotic treatment in children with suspected or confirmed sepsis in ICU settings. Additional research is needed to examine whether the outcomes presented in this report are fully generalisable to the UK.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014010822.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Procalcitonin-guided antibiotic treatment in critically ill patients

PURPOSE

In critically ill patients, length of antibiotic treatment can be effectively guided by procalcitonin (PCT) protocols. International sepsis guidelines and guidelines on antibiotic stewardship strategies recommend PCT as helpful laboratory marker for a rational use of antibiotics. A number of studies and meta-analyses have confirmed the effectiveness of PCT-protocols for shortening antibiotic treatment without compromising clinical outcome in critically ill patients. But in clinical practice, there is still uncertainty how to interpret PCT levels and how to adjust antibiotic treatment in various infectious situations, especially in the perioperative period.

METHODS

This narrative review gives an overview on the application of PCT-protocols in critically ill patients with severe bacterial infections on the basis of 5 case reports and the available literature. Beside strengths and limitations of this biomarker, also varying kinetics and different maximum values with regard to the infectious focus and pathogens are discussed.

RESULTS

PCT-guided antibiotic treatment appears to be safe and effective. Most of the studies revealed a shorter antibiotic treatment without negative clinical outcomes. Cost effectiveness is still a matter of debate and effects on bacterial resistance due to shorter treatments, possible lower rates of drug-related adverse events, or decreased rates of Clostridium difficile infections are not yet evaluated.

CONCLUSION

Guidance of antibiotic treatment can effectively be supported by PCT-protocols. However, it is important to consider the limitations of this biomarker and to use PCT protocols along with antibiotic stewardship programmes and regular clinical rounds together with infectious diseases specialists.

Usefulness of serum procalcitonin as a diagnostic biomarker of infection in children with chronic kidney disease

INTRODUCTION

Serum procalcitonin (PCT) levels are known to be low in healthy individuals in healthy subjects but are increased in patients with a severe bacterial infection. It has not been extensively studied in children with chronic kidney disease (CKD), treated either with hemodialysis (HD) or with renal transplantation.

MATERIAL AND METHODS

During a 6-month period, blood samples were taken from 102 (55 HD children and 47 renal transplant recipients) children with a strong clinical suspicion of infection. Procalcitonin levels were measured by ELISA.

RESULTS

Thirty-four/102 cases had proven infections as defined previously. Children with proven infections had a significantly higher PCT (0.920 ±0.24 ng/ml) than those without (0.456 ±0.53 ng/ml), p = 0.04. The ideal cutoff value derived for serum PCT was 0.5 ng/ml. This threshold value established a sensitivity of 94.1% and a specificity of 87.9%.

CONCLUSIONS

This study indicates that significantly increased PCT concentration is a promising predictor of systemic bacterial infection in children with CKD, with good sensitivity and specificity. This study proposes that serum PCT is a convenient index of infection in CKD children at a cutoff value of 0.5 ng/ml.

Performance of C-reactive protein and procalcitonin to distinguish viral from bacterial and malarial causes of fever in Southeast Asia

BACKGROUND

Poor targeting of antimicrobial drugs contributes to the millions of deaths each year from malaria, pneumonia, and other tropical infectious diseases. While malaria rapid diagnostic tests have improved use of antimalarial drugs, there are no similar tests to guide the use of antibiotics in undifferentiated fevers. In this study we estimate the diagnostic accuracy of two well established biomarkers of bacterial infection, procalcitonin and C-reactive protein (CRP) in discriminating between common viral and bacterial infections in malaria endemic settings of Southeast Asia.

METHODS

Serum procalcitonin and CRP levels were measured in stored serum samples from febrile patients enrolled in three prospective studies conducted in Cambodia, Laos and, Thailand. Of the 1372 patients with a microbiologically confirmed diagnosis, 1105 had a single viral, bacterial or malarial infection. Procalcitonin and CRP levels were compared amongst these aetiological groups and their sensitivity and specificity in distinguishing bacterial infections and bacteraemias from viral infections were estimated using standard thresholds.

RESULTS

Serum concentrations of both biomarkers were significantly higher in bacterial infections and malaria than in viral infections. The AUROC for CRP in discriminating between bacterial and viral infections was 0.83 (0.81-0.86) compared with 0.74 (0.71-0.77) for procalcitonin (p < 0.0001). This relative advantage was evident in all sites and when stratifying patients by age and admission status. For CRP at a threshold of 10 mg/L, the sensitivity of detecting bacterial infections was 95% with a specificity of 49%. At a threshold of 20 mg/L sensitivity was 86% with a specificity of 67%. For procalcitonin at a low threshold of 0.1 ng/mL the sensitivity was 90% with a specificity of 39%. At a higher threshold of 0.5 ng/ul sensitivity was 60% with a specificity of 76%.

CONCLUSION

In samples from febrile patients with mono-infections from rural settings in Southeast Asia, CRP was a highly sensitive and moderately specific biomarker for discriminating between viral and bacterial infections. Use of a CRP rapid test in peripheral health settings could potentially be a simple and affordable measure to better identify patients in need of antibacterial treatment and part of a global strategy to combat the emergence of antibiotic resistance.

Solving the fever mystery: Fever and tonsillar ulcer in an elderly patient

Pyrexia of unknown origin in the elderly is not an uncommon clinical problem. In day to day clinical practice, it has been observed that antibiotics are often empirically escalated to ‘treat fever’ in an otherwise well patient. However, this may not be warranted. It is more important that a comprehensive history, detailed physical examination and a systematic evaluation be undertaken to identify the cause so that definitive therapy may be administered. Apart from infection, neoplastic and connective tissue disorders are other common causes of pyrexia of unknown origin which should be considered. We describe our approach for evaluating an 80-year-old man who presented with fever and sore throat.

Cutoff value of serum procalcitonin as a diagnostic biomarker of infection in end-stage renal disease patients

BACKGROUND/AIMS

Serum procalcitonin (PCT) levels are low in healthy individuals but are elevated in patients with a serious bacterial infection or sepsis. In this study, we examined the ability of serum PCT concentration to diagnose infections in end-stage renal disease (ESRD) patients, and sought to determine an appropriate threshold level.

METHODS

Serum PCT levels were measured in ESRD patients on antibiotic therapy for a suspected bacterial infection (ESRD infection [iESRD] group, n = 21), and compared with those of ESRD patients on hemodialysis with no sign of infection (ESRD control [cESRD] group, n = 20).

RESULTS

The mean serum PCT concentration of the iESRD group was significantly higher than in the cESRD group (2.95 ± 3.67 ng/mL vs. 0.50 ± 0.49 ng/mL, p = 0.006), but serum PCT concentrations did not correlate with severity of infection. The optimized threshold level derived for serum PCT was 0.75 ng/mL, rather than the currently used 0.5 ng/mL; this threshold demonstrated a sensitivity and specificity of 76.2% and 80.0% for infection and 100% and 60.6% for systemic inflammatory response syndrome, respectively, compared with the cutoff of 0.5 ng/mL.

CONCLUSIONS

This study suggests that serum PCT at a cutoff value of 0.75 ng/mL is an appropriate indicator of infection in ESRD patients.

Antibiotic consumption after implementation of a procalcitonin-guided antimicrobial stewardship programme in surgical patients admitted to an intensive care unit: a retrospective before-and-after analysis

PURPOSE

To analyse antibiotic use density (AD)--World Health Organization defined daily doses/1,000 patient-days--before and after implementation of a local antimicrobial stewardship programme (ASP) in conjunction with a procalcitonin (PCT)-guided protocol in a surgical intensive care unit (ICU).

METHODS

In this retrospective observational study, data on 2,422 ICU patients between 2010 and 2012 were analysed. In 2011, an ASP in conjunction with a PCT protocol had been introduced into clinical practice. In a multivariate analysis, hospital mortality, length of stay (LOS) in hospital and ICU LOS were adjusted for effects from effective cost weight, gender, and age. AD and changes in the use of antibiotic classes were analysed.

RESULTS

AD decreased from 1,005.0 in 2010 to 791.9 in 2012 which is a total reduction of 21.2%. Consumption of aminoglycosides, cephalosporins and quinolones showed a marked reduction, whereas the use of penicillins did not change significantly. The multivariate models revealed no relevant changes in mortality rate, ICU LOS and hospital LOS.

CONCLUSIONS

Implementation of an ASP in conjunction with a PCT protocol in 2011 was associated with a marked decrease in total AD and led to a significant change in the spectrum of antibiotics. Clinical outcomes appeared to remain unchanged over the study period.

Procalcitonin: potential role in diagnosis and management of sepsis

Sepsis is an important cause of worldwide morbidity and mortality. Early recognition and diagnosis are keys to achieving improved outcomes. Procalcitonin has been widely investigated as a potential biomarker for sepsis. Furthermore, management of sepsis and other infectious disease is becoming increasingly complicated by the emergence of antibiotic resistant strains of pathogens. Good antibiotic governance is important in reducing the risk of the development of further antibiotic resistance. We reviewed the current literature on the use of procalcitonin in sepsis to determine whether it should be recommended for use in either of these roles. Procalcitonin should not be used as a stand-alone diagnostic test to rule-in or rule-out sepsis or bacterial infection, or for prognostication, in the absence of clinical judgment. Used as part of a clinical algorithm, however, it has been shown to reduce antibiotic prescribing in critical care environments and for respiratory tract infections.

A PCT algorithm for discontinuation of antibiotic therapy is a cost-effective way to reduce antibiotic exposure in adult intensive care patients with sepsis

OBJECTIVE

Procalcitonin (PCT) is a specific marker for differentiating bacterial from non-infective causes of inflammation. It can be used to guide initiation and duration of antibiotic therapy in intensive care unit (ICU) patients with suspected sepsis, and might reduce the duration of hospital stay. Limiting antibiotic treatment duration is highly important because antibiotic over-use may cause patient harm, prolonged hospital stay, and resistance development. Several systematic reviews show that a PCT algorithm for antibiotic discontinuation is safe, but upfront investment required for PCT remains an important barrier against implementation. The current study investigates to what extent this PCT algorithm is a cost-effective use of scarce healthcare resources in ICU patients with sepsis compared to current practice.

METHODS

A decision tree was developed to estimate the health economic consequences of the PCT algorithm for antibiotic discontinuation from a Dutch hospital perspective. Input data were obtained from a systematic literature review. When necessary, additional information was gathered from open interviews with clinical chemists and intensivists. The primary effectiveness measure is defined as the number of antibiotic days, and cost-effectiveness is expressed as incremental costs per antibiotic day avoided.

RESULTS

The PCT algorithm for antibiotic discontinuation is expected to reduce hospital spending by circa € 3503 per patient, indicating savings of 9.2%. Savings are mainly due to reductions in length of hospital stay, number of blood cultures performed, and, importantly, days on antibiotic therapy. Probabilistic and one-way sensitivity analyses showed the model outcome to be robust against changes in model inputs.

CONCLUSION

Proven safe, a PCT algorithm for antibiotic discontinuation is a cost-effective means of reducing antibiotic exposure in adult ICU patients with sepsis, compared to current practice. Additional resources required for PCT are more than offset by downstream cost savings. This finding is highly important given the aim of preventing widespread antibiotic resistance.

Antimicrobial resistance: risk associated with antibiotic overuse and initiatives to reduce the problem

Antimicrobial resistance is a global public health challenge, which has accelerated by the overuse of antibiotics worldwide. Increased antimicrobial resistance is the cause of severe infections, complications, longer hospital stays and increased mortality. Overprescribing of antibiotics is associated with an increased risk of adverse effects, more frequent re-attendance and increased medicalization of self-limiting conditions. Antibiotic overprescribing is a particular problem in primary care, where viruses cause most infections. About 90% of all antibiotic prescriptions are issued by general practitioners, and respiratory tract infections are the leading reason for prescribing. Multifaceted interventions to reduce overuse of antibiotics have been found to be effective and better than single initiatives. Interventions should encompass the enforcement of the policy of prohibiting the over-the-counter sale of antibiotics, the use of antimicrobial stewardship programmes, the active participation of clinicians in audits, the utilization of valid rapid point-of-care tests, the promotion of delayed antibiotic prescribing strategies, the enhancement of communication skills with patients with the aid of information brochures and the performance of more pragmatic studies in primary care with outcomes that are of clinicians' interest, such as complications and clinical outcomes.

Evaluation of procalcitonin as a marker to predict antibiotic response in adult patients with acute appendicitis: a prospective observational study

BACKGROUND

The aim of the study was to investigate the value of serum procalcitonin (PCT) as a predictor of early antibiotic treatment response in patients with acute appendicitis. Procalcitonin is a biochemical marker that increases rapidly in cases of bacterial infection and sepsis; however, the benefit of PCT as a diagnostic tool in acute appendicitis has not been confirmed.

METHODS

Observations of PCT dynamics were conducted as part of a prospective clinical trial at Sahlgrenska University Hospital between May 2009 and February 2010 on adult patients with acute appendicitis treated with antibiotics as first-line therapy. Procalcitonin, C-reactive protein (CRP), and white blood cell count (WBC) were measured before administration of antibiotics and subsequently between 4-24 h following treatment.

RESULTS

Three hundred sixteen patients were included in the study. Almost 80% recovered on antibiotics without the need of surgery. Serum PCT concentrations before initiation of antibiotic therapy and during treatment did not differ significantly between antibiotic responders and non-responders (p<0.94). However, differences were observed for CRP (p<0.04) and WBC (p<0.001), with a trend for body temperature (p<0.06).

CONCLUSION

Procalcitonin has limited additional value, compared with standard laboratory tests as CRP, WBC, and body temperature to predict antibiotic treatment response in adult patients with acute appendicitis.

Biomarkers for sepsis: a review with special attention to India

Sepsis is a serious infection and still a common cause of morbidity and mortality in resource-limited settings such as India. Even when microbiologic diagnostics are available, bacteremia is only identified in a proportion of patients who present with sepsis and bloodstream infections. Biomarkers have been used in a variety of disease processes and can help aid in diagnosing bacterial infections. There have been numerous biomarkers investigated to aid with diagnosis and prognostication in sepsis with the majority suffering from lack of sensitivity or specificity. Procalcitonin has been heralded as the biomarker that holds the most promise for bloodstream infections. Data are emerging in India, and in this review, we focus on the current data of biomarkers in sepsis with particular attention to how biomarkers could be used to augment diagnosis and treatment in India.

Procalcitonin guided antibiotic therapy of acute exacerbations of asthma: a randomized controlled trial

Background

This randomized controlled trial aimed to evaluate whether the serum procalcitonin (PCT) level can be utilized to guide the use of antibiotics in the treatment of acute exacerbations of asthma.

Methods

A total of 293 consecutive patients with suspected asthma attacks from February 2005 to July 2010 participated in this study. 225 patients completed the study. Serum PCT levels, and other inflammatory biomarkers of all patients were measured. In addition to the standard treatment, the control group received antibiotics according to the attending physicians’ discretions, while the patients in the PCT group were treated with antibiotics according to serum PCT concentrations. Antibiotics usage was strongly discouraged when the PCT concentration was below 0.1 μg/L; discouraged when the PCT concentration was between 0.1 μg/L and 0.25 μg/L; or encouraged when the PCT concentration was above 0.25 μg/L. The primary endpoint was the determination of antibiotics usage. The second endpoints included the diagnostic accuracy of PCT and other laboratory biomarkers the effectiveness of asthma control, secondary ED visits, hospital re-admissions, repeated needs for steroids or dosage increase, needs for antibiotics, WBC count, PCT levels and FEV1%.

Results

At baseline, two groups were identical regarding clinical, laboratory and symptom score. Probability of the antibiotics usage in the PCT group (46.1%) was lower than that in the control group (74.8%) (χ² = 21.97, p < 0.001. RR = 0.561, 95% CI 0.441-0.713). PCT and IL-6 showed good diagnostic significance for bacterial asthma (r = 0.705, p = 0.003). The degrees of asthma control in patients were categorized to three levels and were comparable between the two groups at the six weeks follow-up period (χ² = 1.62, p = 0.45). There were no significant difference regarding other secondary outcomes (p > 0.05).

Conclusions

The serum PCT concentration can be used to effectively determine whether the acute asthma patients have bacterial infections in the respiratory tract, and to guide the use of antibiotics in the treatment of acute asthma exacerbations, which may substantially reduce unnecessary antibiotic use without compromising the therapeutic outcomes.

Trial registration

ICTRP ChiCTR-TRC-12002534

Procalcitonin-guided therapy in intensive care unit patients with severe sepsis and septic shock--a systematic review and meta-analysis

Introduction

Procalcitonin (PCT) algorithms for antibiotic treatment decisions have been studied in adult patients from primary care, emergency department, and intensive care unit (ICU) settings, suggesting that procalcitonin-guided therapy may reduce antibiotic exposure without increasing the mortality rate. However, information on the efficacy and safety of this approach in the most vulnerable population of critically ill patients with severe sepsis and septic shock is missing.

Method

Two reviewers independently performed a systematic search in PubMed, Embase, ISI Web of Knowledge, BioMed Central, ScienceDirect, Cochrane Central Register of Controlled Trials, http://www.ClinicalTrials.gov and http://www.ISRCTN.org.

Eligible studies had to be randomized controlled clinical trials or cohort studies which compare procalcitonin-guided therapy with standard care in severe sepsis patients and report at least one of the following outcomes: hospital mortality, 28-day mortality, duration of antimicrobial therapy, length of stay in the intensive care unit or length of hospital stay. Disagreements about inclusion of studies and judgment of bias were solved by consensus.

Results

Finally seven studies comprising a total of 1,075 patients with severe sepsis or septic shock were included in the meta-analysis.

Both hospital mortality (RR [relative risk]: 0.91, 95%CI [confidence interval]: 0.61; 1.36) and 28-day mortality (RR: 1.02, 95%CI: 0.85; 1.23) were not different between procalcitonin-guided therapy and standard treatment groups.

Duration of antimicrobial therapy was significantly reduced in favor of procalcitonin-guided therapy (HR [hazard ratio]: 1.27, 95%CI: 1.01; 1.53). Combined estimates of the length of stay in the ICU and in hospital did not differ between groups.

Conclusion

Procalcitonin-guided therapy is a helpful approach to guide antibiotic therapy and surgical interventions without a beneficial effect on mortality. The major benefit of PCT-guided therapy consists of a shorter duration of antibiotic treatment compared to standard care.

Trials are needed to investigate the effect of PCT-guided therapy on mortality, length of ICU and in-hospital stay in severe sepsis patients.

Kinetics of procalcitonin and C-reactive protein and the relationship to postoperative infection in young infants undergoing cardiovascular surgery

BACKGROUND

The utility of procalcitonin (PCT) and C-reactive protein (CRP) as infectious biomarkers following infant cardiothoracic surgery is not well defined.

METHODS

We designed a prospective cohort study to evaluate PCT and CRP after infant cardiothoracic surgery. PCT and CRP were drawn preoperatively and 24/72 h postoperation or daily in delayed sternal closure patients. Presence of infection within 10 d of surgery, vasoactive-inotropic scores at 24 and 72 h, and length of intubation, intensive care unit stay, and hospital stay were documented.

RESULTS

PCT and CRP were elevated at 24 h. PCT then decreased while CRP increased in patients undergoing delayed sternal closure or cardiopulmonary bypass. In the delayed sternal closure group, PCT was significantly higher on postoperative days 2-5 in patients who ultimately developed infection. Higher PCT was independently associated with increased vasoactive-inotropic score at 72 h. CRP did not correlate with infection or postoperative support.

CONCLUSION

PCT rises after cardiothoracic surgery in infants but decreases by 72 h while CRP remains elevated. Sternal closure may affect CRP but not PCT. PCT is independently associated with circulatory support requirements at 72 h postoperation and with development of infection. PCT may have greater utility as a biomarker in this population.

Emerging Infectious Diseases, Antimicrobial Resistance and Millennium Development Goals: Resolving the Challenges through One Health

Most emerging infectious diseases are zoonoses, which could severely hamper reaching the targets of millennium development goals (MDG). Five out of the total eight MDG's are strongly associated with the Emerging Infectious Diseases (EIDs). Recent emergence and dissemination of drug-resistant pathogens has accelerated and prevent reaching the targets of MDG, with shrinking of therapeutic arsenal, mostly due to antimicrobial resistance (AMR). World Health Organization (WHO has identified AMR as 1 of the 3 greatest threats to global health. Until now, methicillin-resistant staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) have been observed in hospital-acquired infections. In India, within a span of three years, New Delhi metallo-β-lactamase prevalence has risen from three percent in hospitals to twenty- fifty percent and is found to be colistin resistant as well. Routine use of antimicrobials in animal husbandry accounts for more than 50% in tonnage of all antimicrobial production to promote growth and prophylaxis. This has consequences to human health and environmental contamination with a profound impact on the environmental microbiome, resulting in resistance. Antibiotic development is now considered a global health crisis. The average time required to receive regulatory approval is 7.2 years. Moreover, the clinical approval success is only 16%. To overcome resistance in antimicrobials, intersectoral partnerships among medical, veterinary, and environmental disciplines, with specific epidemiological, diagnostic, and therapeutic approaches are needed. Joint efforts under "One Health", beyond individual professional boundaries are required to stop antimicrobial resistance against zoonoses (EID) and reach the MDG.

Procalcitonin-guided antibiotic therapy: a systematic review and meta-analysis

BACKGROUND

The utility of procalcitonin to manage patients with infections is unclear. A systematic review of comparative studies using procalcitonin-guided antibiotic therapy in patients with infections was performed.

METHODS

Randomized, controlled trials comparing procalcitonin-guided initiation, intensification, or discontinuation of antibiotic therapy to clinically guided therapy were included. Outcomes were antibiotic usage, morbidity, and mortality. MEDLINE, EMBASE, the Cochrane Database, National Institute for Clinical Excellence, the National Guideline Clearinghouse, and the Health Technology Assessment Programme were searched from January 1, 1990 to December 16, 2011.

RESULTS

Eighteen randomized, controlled trials were included. Data were pooled into clinically similar patient populations. In adult intensive care unit (ICU) patients, procalcitonin-guided discontinuation of antibiotics reduced antibiotic duration by 2.05 days (95% confidence interval [CI]: -2.59 to -1.52) without increasing morbidity or mortality. In contrast, procalcitonin-guided intensification of antibiotics in adult ICU patients increased antibiotic usage and morbidity. In adult patients with respiratory tract infections, procalcitonin guidance significantly reduced antibiotic duration by 2.35 days (95% CI: -4.38 to -0.33), antibiotic prescription rate by 22% (95% CI: -41% to -4%), and total antibiotic exposure without affecting morbidity or mortality. A single, good quality study of neonates with suspected sepsis demonstrated reduced antibiotic duration by 22.4 hours (P = 0.012) and reduced the proportion of neonates on antibiotics for ≥ 72 hours by 27% (P = 0.002) with procalcitonin guidance.

CONCLUSION

Procalcitonin guidance can safely reduce antibiotic usage when used to discontinue antibiotic therapy in adult ICU patients and when used to initiate or discontinue antibiotics in adult patients with respiratory tract infections.

Biomarkers as predictors of outcome after cardiac arrest

Cardiac arrest (CA) is a major health and economic problem. Management of patients resuscitated from CA is challenging for clinicians, and the mortality rate of those who achieve return of spontaneous circulation remains high. Hypoxic brain injury, cardiovascular abnormalities and systemic ischemia/reperfusion response characterize the so-called 'postcardiac arrest syndrome', which could lead to multiple organ failure and poor outcome after CA. The magnitude of these disorders differs in individual patients, mainly based on the cause and duration of CA and on the severity of the ischemic episode. Prognostication of outcome after CA is of importance because it could help physicians on triage decisions and readdress the overall management. A number of factors are thought to influence the prognosis of patients after CA, but due to the heterogeneity of CA population and scenarios no single factor has been identified as a reliable predictor of outcome and the timing and optimal approach to prognostication is still controversial. Biomarkers represent a growing area of interest in this field, as they may provide clinicians with early information on the severity of organ dysfunction to make a decision on clinical strategies and prognosticate outcome. In this article, the authors will focus on cardiac, neurological and inflammatory biomarkers as potential predictors of outcome after CA.

Nosocomial pneumonia: lessons learned

Nosocomial pneumonia remains a significant cause of hospital-acquired infection, imposing substantial economic burden on the health care system worldwide. Various preventive strategies have been increasingly used to prevent the development of pneumonia. It is now recognized that patients with health care-associated pneumonia are a heterogeneous population and that not all are at risk for infection with nosocomial pneumonia pathogens, with some being infected with the same organisms as in community-acquired pneumonia. This review discusses the risk factors for nosocomial pneumonia, controversies in its diagnosis, and approaches to the treatment and prevention of nosocomial and health care-associated pneumonia.

Procalcitonin-guided algorithm to reduce length of antibiotic therapy in patients with severe sepsis and septic shock

BACKGROUND

Procalcitonin (PCT)-protocols to guide antibiotic treatment in severe infections are known to be effective. But less is known about the long-term effects of such protocols on antibiotic consumption under real life conditions. This retrospective study analyses the effects on antibiotic use in patients with severe sepsis and septic shock after implementation of a PCT-protocol.

METHODS

We conducted a retrospective ICU-database search for adult patients between 2005 and 2009 with sepsis and organ dysfunction who where treated accordingly to a PCT-guided algorithm as follows: Daily measurements of PCT (BRAHMS PCT LIA(®); BRAHMS Aktiengesellschaft, Hennigsdorf, Germany). Antibiotic therapy was discontinued if 1) clinical signs and symptoms of infection improved and PCT decreased to ≤1 ng/ml, or 2) if the PCT value was >1 ng/ml, but had dropped to 25-35% of the initial value within three days. The primary outcome parameters were: antibiotic days on ICU, ICU re-infection rate, 28-day mortality rate, length of stay (LOS) in ICU, mean antibiotic costs (per patient) and ventilation hours. Data from 141 patients were included in our study. Primary outcome parameters were analysed using covariance analyses (ANCOVA) to control for effects by gender, age, SAPS II, APACHE II and effective cost weight.

RESULTS

From baseline data of 2005, duration of antibiotic therapy was reduced by an average of 1.0 day per year from 14.3 ±1.2 to 9.0 ±1.7 days in 2009 (p=0.02). ICU re-infection rate was decreased by yearly 35.1% (95% CI -53 to -8.5; p=0.014) just as ventilation hours by 42 hours per year (95% CI -72.6 to -11.4; p=0.008). ICU-LOS was reduced by 2.7 days per year (p<0.001). Trends towards an average yearly reduction of 28-day mortality by -22.4% (95% CI -44.3 to 8.1; p=0.133) and mean cost for antibiotic therapy/ patient by -14.3 Euro (95% CI -55.7 to 27.1) did not reach statistical significance.

CONCLUSIONS

In a real-life clinical setting, implementation of a PCT-protocol was associated with a reduced duration of antibiotic therapy in septic ICU patients without compromising clinical or economical outcomes. GERMAN CLINICAL TRIALS REGISTER: DRKS00003490.

Seven ways to preserve the miracle of antibiotics

Antibiotic resistance is a well-acknowledged crisis with no clearly defined comprehensive, national corrective plan. We propose a number of interventions that, collectively, could make a large difference. These include collection of data to inform decisions, efforts to reduce antibiotic abuse in people and animals, great emphasis on antibiotic stewardship, performance incentives, optimal use of newer diagnostics, better support for clinical and basic resistance-related research, and novel methods to foster new antibiotic development.

Pentraxin 3 (PTX3) is associated with severe sepsis and fatal disease in emergency room patients with suspected infection: a prospective cohort study

BACKGROUND

Early diagnostic and prognostic stratification of patients with suspected infection is a difficult clinical challenge. We studied plasma pentraxin 3 (PTX3) upon admission to the emergency department in patients with suspected infection.

METHODS

The study comprised 537 emergency room patients with suspected infection: 59 with no systemic inflammatory response syndrome (SIRS) and without bacterial infection (group 1), 67 with bacterial infection without SIRS (group 2), 54 with SIRS without bacterial infection (group 3), 308 with sepsis (SIRS and bacterial infection) without organ failure (group 4) and 49 with severe sepsis (group 5). Plasma PTX3 was measured on admission using a commercial solid-phase enzyme-linked immunosorbent assay (ELISA).

RESULTS

The median PTX3 levels in groups 1-5 were 2.6 ng/ml, 4.4 ng/ml, 5.0 ng/ml, 6.1 ng/ml and 16.7 ng/ml, respectively (p<0.001). The median PTX3 concentration was higher in severe sepsis patients compared to others (16.7 vs. 4.9 ng/ml, p<0.001) and in non-survivors (day 28 case fatality) compared to survivors (14.1 vs. 5.1 ng/ml, p<0.001). A high PTX3 level predicted the need for ICU stay (p<0.001) and hypotension (p<0.001). AUC(ROC) in the prediction of severe sepsis was 0.73 (95% CI 0.66-0.81, p<0.001) and 0.69 in case fatality (95% CI 0.58-0.79, p<0.001). PTX3 at a cut-off level for 14.1 ng/ml (optimal cut-off value for severe sepsis) showed 63% sensitivity and 80% specificity. At a cut-off level 7.7 ng/ml (optimal cut-off value for case fatality) showed 70% sensitivity and 63% specificity in predicting case fatality on day 28.In multivariate models, high PTX3 remained an independent predictor of severe sepsis and case fatality after adjusting for potential confounders.

CONCLUSIONS

A high PTX3 level on hospital admission predicts severe sepsis and case fatality in patients with suspected infection.

Diagnostic value of serum procalcitonin in patients with chronic renal insufficiency: a systematic review and meta-analysis

BACKGROUND

The diagnostic value of procalcitonin (PCT) for patients with renal impairment is unclear.

METHODS

We searched multiple databases for studies published through December 2011 that evaluated the diagnostic performance of PCT among patients with renal impairment and suspected systemic bacterial infection. We summarized test performance characteristics with the use of forest plots, hierarchical summary receiver operating characteristic (HSROC) curves, and bivariate random effects models.

RESULTS

Our search identified 201 citations, of which seven diagnostic studies evaluated 803 patients and 255 bacterial infection episodes. HSROC-bivariate pooled sensitivity estimates were 73% [95% confidence interval (95% CI) 54-86%] for PCT tests and 78% (95% CI 52-92%) for CRP tests. Pooled specificity estimates were higher for both PCT and CRP tests [PCT, 88% (95% CI 79-93%); CRP, 84% (95% CI, 52-96%)]. The positive likelihood ratio for PCT [likelihood (LR)+ 6.02, 95% CI 3.16-11.47] was sufficiently high to be qualified as a rule-in diagnostic tool, while the negative likelihood ratio was not low enough to be used as a rule-out diagnostic tool (LR- 0.31, 95% CI 0.17-0.57). There was no consistent evidence that PCT was more accurate than CRP test for the diagnosis of systemic infection among patients with renal impairment.

CONCLUSIONS

Both PCT and CRP tests have poor sensitivity but acceptable specificity in diagnosing bacterial infection among patients with renal impairment. Given the poor negative likelihood ratio, its role as a rule-out test is questionable.