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

Benefits and Harms of Procalcitonin- or C-Reactive Protein-Guided Antimicrobial Discontinuation in Critically Ill Adults With Sepsis: A Systematic Review and Network Meta-Analysis

OBJECTIVES

In sepsis treatment, antibiotics are crucial, but overuse risks development of antibiotic resistance. Recent guidelines recommended the use of procalcitonin to guide antibiotic cessation, but solid evidence is insufficient. Recently, concerns were raised that this strategy would increase recurrence. Additionally, optimal protocol or difference from the commonly used C-reactive protein (CRP) are uncertain. We aimed to compare the effectiveness and safety of procalcitonin- or CRP-guided antibiotic cessation strategies with standard of care in sepsis.

DATA SOURCES

A systematic search of PubMed, Embase, CENTRAL, Igaku Chuo Zasshi, ClinicalTrials.gov , and World Health Organization International Clinical Trials Platform.

STUDY SELECTION

Randomized controlled trials involving adults with sepsis in intensive care.

DATA EXTRACTION

A systematic review with network meta-analyses was performed. The Grading of Recommendations, Assessments, Developments, and Evaluation method was used to assess certainty.

DATA SYNTHESIS

Eighteen studies involving 5023 participants were included. Procalcitonin-guided and CRP-guided strategies shortened antibiotic treatment (-1.89 days [95% CI, -2.30 to -1.47], -2.56 days [95% CI, -4.21 to -0.91]) with low- to moderate-certainty evidence. In procalcitonin-guided strategies, this benefit was consistent even in subsets with shorter baseline antimicrobial duration (7-10 d) or in Sepsis-3, and more pronounced in procalcitonin cutoff of "0.5 μg/L and 80% reduction." No benefit was observed when monitoring frequency was less than half of the initial 10 days. Procalcitonin-guided strategies lowered mortality (-27 per 1000 participants [95% CI, -45 to -7]) and this was pronounced in Sepsis-3, but CRP-guided strategies led to no difference in mortality. Recurrence did not increase significantly with either strategy (very low to low certainty).

CONCLUSIONS

In sepsis, procalcitonin- or CRP-guided antibiotic discontinuation strategies may be beneficial and safe. In particular, the usefulness of procalcitonin guidance for current Sepsis-3, where antimicrobials are used for more than 7 days, was supported. Well-designed studies are needed focusing on monitoring protocol and recurrence.

Deprescribing: An umbrella review

This umbrella review examined systematic reviews of deprescribing studies by characteristics of intervention, population, medicine, and setting. Clinical and humanistic outcomes, barriers and facilitators, and tools for deprescribing are presented. The Medline database was used. The search was limited to systematic reviews and meta-analyses published in English up to April 2022. Reviews reporting deprescribing were included, while those where depre-scribing was not planned and supervised by a healthcare professional were excluded. A total of 94 systematic reviews (23 meta--analyses) were included. Most explored clinical or humanistic outcomes (70/94, 74 %); less explored attitudes, facilitators, or barriers to deprescribing (17/94, 18 %); few focused on tools (8/94, 8.5 %). Reviews assessing clinical or humanistic outcomes were divided into two groups: reviews with deprescribing intervention trials (39/70, 56 %; 16 reviewing specific deprescribing interventions and 23 broad medication optimisation interventions), and reviews with medication cessation trials (31/70, 44 %). Deprescribing was feasible and resulted in a reduction of inappropriate medications in reviews with deprescribing intervention trials. Complex broad medication optimisation interventions were shown to reduce hospitalisation, falls, and mortality rates. In reviews of medication cessation trials, a higher frequency of adverse drug withdrawal events underscores the importance of prioritizing patient safety and exercising caution when stopping medicines, particularly in patients with clear and appropriate indications.

Comparative Impact of an Optimized PK/PD Target Attainment of Piperacillin-Tazobactam vs. Meropenem on the Trend over Time of SOFA Score and Inflammatory Biomarkers in Critically Ill Patients Receiving Continuous Infusion Monotherapy for Treating Documented Gram-Negative BSIs and/or VAP

(1) Background: The advantage of using carbapenems over beta-lactam/beta-lactamase inhibitor combinations in critically ill septic patients still remains a debated issue. We aimed to assess the comparative impact of an optimized pharmacokinetic/pharmacodynamic (PK/PD) target attainment of piperacillin-tazobactam vs. meropenem on the trend over time of both Sequential Organ Failure Assessment (SOFA) score and inflammatory biomarkers in critically ill patients receiving continuous infusion (CI) monotherapy with piperacillin-tazobactam or meropenem for treating documented Gram-negative bloodstream infections (BSI) and/or ventilator-associated pneumonia (VAP). (2) Methods: We performed a retrospective observational study comparing critically ill patients receiving targeted treatment with CI meropenem monotherapy for documented Gram-negative BSIs or VAP with a historical cohort of critical patients receiving CI piperacillin-tazobactam monotherapy. Patients included in the two groups were admitted to the general and post-transplant intensive care unit in the period July 2021-September 2023 and fulfilled the same inclusion criteria. The delta values of the SOFA score between the baseline of meropenem or piperacillin-tazobactam treatment and those at 48-h (delta 48-h SOFA score) or at 7-days (delta 7-days SOFA) were selected as primary outcomes. Delta 48-h and 7-days C-reactive protein (CRP) and procalcitonin (PCT), microbiological eradication, resistance occurrence, clinical cure, multi-drug resistant colonization at 90-day, ICU, and 30-day mortality rate were selected as secondary outcomes. Univariate analysis comparing primary and secondary outcomes between critically ill patients receiving CI monotherapy with piperacillin-tazobactam vs. meropenem was carried out. (3) Results: Overall, 32 critically ill patients receiving CI meropenem monotherapy were compared with a historical cohort of 43 cases receiving CI piperacillin-tazobactam monotherapy. No significant differences in terms of demographics and clinical features emerged at baseline between the two groups. Optimal PK/PD target was attained in 83.7% and 100.0% of patients receiving piperacillin-tazobactam and meropenem, respectively. No significant differences were observed between groups in terms of median values of delta 48-h SOFA (0 points vs. 1 point; p = 0.89) and median delta 7-days SOFA (2 points vs. 1 point; p = 0.43). Similarly, no significant differences were found between patients receiving piperacillin-tazobactam vs. meropenem for any of the secondary outcomes. (4) Conclusion: Our findings may support the contention that in critically ill patients with documented Gram-negative BSIs and/or VAP, the decreases in the SOFA score and in the inflammatory biomarkers serum levels achievable with CI piperacillin-tazobactam monotherapy at 48-h and at 7-days may be of similar extent and as effective as to those achievable with CI meropenem monotherapy provided that optimization on real-time by means of a TDM-based expert clinical pharmacological advice program is granted.

Effects of procalcitonin on antimicrobial treatment decisions in patients with coronavirus disease 2019 (COVID-19)

OBJECTIVE

To describe the natural course of procalcitonin (PCT) in patients with coronavirus disease 2019 (COVID-19) and the correlation between PCT and antimicrobial prescribing to provide insight into best practices for PCT data utilization in antimicrobial stewardship in this population.

DESIGN

Single-center, retrospective, observational study.

SETTING

Michigan Medicine.

PATIENTS

Inpatients aged ≥18 years hospitalized March 1, 2020, through October 31, 2021, who were positive for severe acute respiratory coronavirus virus 2 (SARS-CoV-2), with ≥1 PCT measurement. Exclusion criteria included antibiotics for nonpulmonary bacterial infection on admission, treatment with azithromycin only for chronic obstructive pulmonary disease (COPD) exacerbation, and pre-existing diagnosis of cystic fibrosis with positive respiratory cultures.

METHODS

A structured query was used to extract data. For patients started on antibiotics, bacterial pneumonia (bPNA) was determined through chart review. Multivariable models were used to assess associations of PCT level and bPNA with antimicrobial use.

RESULTS

Of 793 patients, 224 (28.2%) were initiated on antibiotics: 33 (14.7%) had proven or probable bPNA, 125 (55.8%) had possible bPNA, and 66 (29.5%) had no bPNA. Patients had a mean of 4.1 (SD, ±5.2) PCT measurements if receiving antibiotics versus a mean of 2.0 (SD, ±2.6) if not. Initial PCT level was highest for those with proven/probable bPNA and was associated with antibiotic initiation (odds ratio 95% confidence interval [CI], 1.17-1.30). Initial PCT (rate ratio [RR] 95% CI, 1.01-1.08), change in PCT over time (RR 95% CI, 1.01-1.05), and bPNA group (RR 95% CI, 1.23-1.84) were associated with antibiotic duration.

CONCLUSIONS

PCT trends are associated with the decision to initiate antibiotics and duration of treatment, independent of bPNA status and comorbidities. Prospective studies are needed to determine whether PCT level can be used to safely make decisions regarding antibiotic treatment for COVID-19.

Low-cost, facile droplet modification of screen-printed arrays for internally validated electrochemical detection of serum procalcitonin

This manuscript presents the design and facile production of screen-printed arrays (SPAs) for the internally validated determination of raised levels of serum procalcitonin (PCT). The screen-printing methodology produced SPAs with six individual working electrodes that exhibit an inter-array reproducibility of 3.64% and 5.51% for the electrochemically active surface area and heterogenous electrochemical rate constant respectively. The SPAs were modified with antibodies specific for the detection of PCT through a facile methodology, where each stage simply uses droplets incubated on the surface, allowing for their mass-production. This platform was used for the detection of PCT, achieving a linear dynamic range between 1 and 10 ng mL^-1 with a sensor sensitivity of 1.35 × 10^-10 NIC%/ng mL^-1. The SPA produced an intra- and inter-day %RSD of 4.00 and 5.05%, with a material cost of £1.14. Internally validated human serum results (3 sample measurements, 3 control) for raised levels of PCT (>2 ng mL^-1) were obtained, with no interference effects seen from CRP and IL-6. This SPA platform has the potential to offer clinicians vital information to rapidly begin treatment for "query sepsis" patients while awaiting results from more lengthy remote laboratory testing methods. Analytical ranges tested make this an ideal approach for rapid testing in specific patient populations (such as neonates or critically ill patients) in which PCT ranges are inherently wider. Due to the facile modification methods, we predict this could be used for various analytes on a single array, or the array increased further to maintain the internal validation of the system.

Should Procalcitonin Be Included in Acute Cholecystitis Guidelines? A Systematic Review

Background and Objectives: Acute cholecystitis (AC) is a common surgical emergency. Recent evidence suggests that serum procalcitonin (PCT) is superior to leukocytosis and serum C-reactive protein in the diagnosis and severity stratification of acute infections. This review evaluates the role of PCT in AC diagnosis, severity stratification, and management. Materials and Methods: PubMed, Embase, and Scopus were searched from inception till 21 August 2022 for studies reporting the role of PCT in AC. A qualitative analysis of the existing literature was conducted. Results: Five articles, including 688 patients, were included. PCT ≤ 0.52 ng/mL had fair discriminative ability (Area under the curve (AUC) 0.721, p < 0.001) to differentiate Grade 1 from Grade 2-3 AC, and PCT > 0.8 ng/mL had good discriminatory ability to differentiate Grade 3 from 1-2 AC (AUC 0.813, p < 0.001). PCT cut-off ≥ 1.50 ng/mL predicted difficult laparoscopic cholecystectomy (sensitivity 91.3%, specificity 76.8%). The incidence of open conversion was higher with PCT ≥ 1 ng/mL (32.4% vs. 14.6%, p = 0.013). A PCT value of >0.09 ng/mL could predict major complications (defined as open conversion, mechanical ventilation, and death). Conclusions: Current evidence is plagued by the heterogeneity of small sample studies. Though PCT has some role in assessing severity and predicting difficult cholecystectomy, and postoperative complications in AC patients, more evidence is necessary to validate its use.

Duration of antimicrobial therapy after video-assisted thoracoscopic surgery for thoracic empyema and complicated parapneumonic effusion: A single-center study

BACKGROUND

There are no evidence-based reports on the proper duration of antimicrobial therapy following video-assisted thoracoscopic surgery debridement (VATS-D) in thoracic empyema (TE) or complicated parapneumonic effusion (PPE). This study aimed to investigate the optimal duration of antimicrobial therapy after VATS-D.

METHODS

Between January 2011 and December 2019, 33 patients corresponding to American College of Chest Physicians (ACCP) category 3 or 4 undergoing VATS-D were included. The times until the body temperature (BT) was confirmed to be less than 37.5 °C and 37.0 °C, white blood cell count (WBC) less than 10,000/μl, segmented neutrophils (seg) less than 80%, and C-reactive protein (CRP) level less than 25% of the preoperative value were retrospectively analyzed.

RESULTS

The median time from the onset of TE/PPE to surgery was 13 days. The median durations of preoperative and postoperative antibiotic use were five and seven days, respectively. Major complications occurred in four cases (three and one cases of respiratory failure and cerebral infarction, respectively). The median postoperative hospital stay was 14 days. Recurrence or progression to chronic empyema was seen in four cases. The median numbers of days until the conditions were met were three days for BT < 37.5 °C, six days for BT < 37.0 °C, four days for WBC<10,000, seven days for seg<80% and seven days for CRP<25%.

CONCLUSIONS

The proper duration of antimicrobial therapy after VATS-D for TE/PPE is approximately three to seven days. Urgent VATS-D may shorten the total antibiotic usage.

Procalcitonin Testing With Secondary Coinfection in Patients With COVID-19

Background

The coronavirus disease (COVID-19) virus has caused millions of deaths. It is difficult to differentiate between pure viral COVID-19 pneumonia and secondary infection. Clinicians often use procalcitonin (PCT) to decide on empiric antibiotic therapy.

Methodology

We performed a retrospective study of patients admitted with COVID-19 between January 1st, 2020, and June 30th, 2020. Patient demographics, clinical findings, and laboratory findings with a focus on PCT levels were recorded. Coinfection was considered if clinicians ordered a septic workup (urine, blood, and respiratory cultures) or if the physicians started or escalated antimicrobial therapy. PCT levels on the day of culture and daily for the next three days were recorded. Significant PCT change was defined as a decrease in PCT levels of >50% from the initial elevated PCT level.

Results

In total, 143 (59.8%) patients had one secondary infection. These included pulmonary infections (118, 49.4%), blood infections (99, 41.4%), and urine infections (64, 26.8%). Many patients had more than one documented positive culture: respiratory system and blood together in 80 (33.4%) patients, sputum and urine in 55 (23.1%) patients, and urine and blood in 46 (19.2%) patients. Out of the 143 patients with a positive culture, PCT was abnormal on the day of positive culture in 93 (65.5%), while PCT was abnormal in 64 out of 96 on the day of negative culture (66.7%) (p = 0.89). Individual analysis for PCT levels of respiratory cultures showed out of 118 positive sputum cultures, 86 (72%) had abnormal PCT on the day of culture. PCT in positive versus negative cultures was not significantly different, with median PCT (interquartile range, IQR) of 1.66 (6.61) versus 1.03 (2.23) (p = 0.172). For blood cultures, out of 99 positive blood cultures, 73 (73%) had abnormal PCT levels on the day of the culture. PCT in positive versus negative cultures was significantly elevated, with a median of 1.61 (5.97) vs. 0.65 (1.77) (p < 0.001). For urine, out of 64 positive cultures, 41 (64.1%) had abnormal PCT levels on the day of the culture. PCT in positive versus negative cultures was not significantly different, with a median of 0.71 (2.92) vs. 0.93 (4.71) (p = 0.551). To observe the change in PCT after culture, PCT values for the next three days after culture were analyzed. We found that patients with positive cultures had higher PCT levels than those with negative cultures. There was no significant improvement over the following three days. Patients with abnormal PCT on the day of the suspected infection had a longer length of stay in the hospital, with a median (IQR) of 23.9 days (3.16) vs. 16.9 days (2.18) (p = 0.021).

Conclusions

Secondary coinfections in patients with COVID-19 infections are not associated with PCT elevation on the day of suspected secondary infection. However, most patients with bacteremia had a significant elevation of PCT on the day of bacteremia before collection and reporting of positive culture. Patients with abnormal PCT levels on the day of suspected infection had a longer hospital stay than patients with normal PCT levels. Subsequent testing of PCT in patients showed no significant improvement in PCT.

Retrospective Cohort Analysis of the Effect of Antimicrobial Stewardship on Postoperative Antibiotic Therapy in Complicated Intra-Abdominal Infections: Short-Course Therapy Does Not Compromise Patients’ Safety

Background: Recent evidence suggests that short-course postoperative antibiotic therapy (PAT) of intra-abdominal infections is non-inferior considering clinical outcomes. The aim of this study was to compare the outcome of short vs. long PAT in complicated intra-abdominal infections (cIAIs) without sepsis. Methods: We performed a single center-quality improvement study at a 1500 bed sized university hospital in Bavaria, Germany, with evaluation of the length of antibiotic therapy after emergency surgery on cIAIs with adequate source control during 2016 to 2018. We reviewed a total of 260 cases (160 short duration vs. 100 long duration). The antibiotic prescribing quality was assessed by our in-house antimicrobial stewardship team (AMS). Results: No significant differences of patient characteristics were observed between short and long PAT. The frequency of long PAT declined during the observation period from 48.1% to 26.3%. Prolongation of PAT was not linked with any clinical benefits, on the contrary clinical outcome of patients receiving longer regimes were associated with higher postoperative morbidity. AMS identified additional educational targets to improve antibiotic prescribing quality on general wards like unnecessary postoperative switches of antibiotic regimes, e.g., unrequired switches to oral antibiotics as well as prolongation of PAT due to elevated CRP. Conclusion: Short-course antibiotic therapy after successful surgical source control in cIAIs is safe, and long-duration PAT has no beneficial effects.

The role of procalcitonin in identifying high-risk cancer patients with febrile neutropenia: A useful alternative to the multinational association for supportive care in cancer score

Background

The Multinational Association for Supportive Care in Cancer (MASCC) risk index has been utilized to determine the risk for poor clinical outcomes in patients with febrile neutropenia (FN) in an emergency center (EC). However, this index comprises subjective elements and elaborated metrics limiting its use in ECs. We sought to determine whether procalcitonin (PCT) level (biomarker of bacterial infection) with or without lactate level (marker of inadequate tissue perfusion) offers a potential alternative to MASSC score in predicting the outcomes of patients with FN presenting to an EC.

Methods

We retrospectively identified 550 cancer patients with FN who presented to our EC between April 2018, and April 2019, and had serum PCT and lactate levels measured.

Results

Compared with patients with PCT levels <0.25 ng/ml, those with levels ≥0.25 ng/ml had a significantly higher 14‐day mortality rate (5.2% vs. 0.7%; p = 0.002), a higher bloodstream infection (BSI) rate, and a longer hospital length of stay (LOS). Logistic regression analysis showed that patients with PCT levels ≥0.25 ng/ml and lactate levels >2.2 mmol/L were more likely to be admitted and have an LOS >7 days, BSI, and 14‐day mortality than patients with lower levels. PCT level was a significantly better predictor of BSI than MASSC score (p = 0.003) or lactate level (p < 0.0001).

Conclusions

Procalcitonin level is superior to MASCC index in predicting BSI. The combination of PCT and lactate levels is a good predictor of BSI, hospital admission, and 14‐day mortality and could be useful in identifying high‐risk FN patients who require hospital admission.

Diagnostic Performance of Procalcitonin for the Early Identification of Sepsis in Patients with Elevated qSOFA Score at Emergency Admission

Infectious biomarkers such as procalcitonin (PCT) can help overcome the lack of sensitivity of the quick Sequential Organ Failure Assessment (qSOFA) score for early identification of sepsis in emergency departments (EDs) and thus might be beneficial as point-of-care biomarkers in EDs. Our primary aim was to investigate the diagnostic performance of PCT for the early identification of septic patients and patients likely to develop sepsis within 96 h of admission to an ED among a prospectively selected patient population with elevated qSOFA score. In a large multi-centre prospective cohort study, we included all adult patients (n = 742) with a qSOFA score of at least 1 who presented to the ED. PCT levels were measured upon admission. Of the study population 27.3% (n = 202) were diagnosed with sepsis within the first 96 h. The area under the curve for PCT for the identification of septic patients in EDs was 0.86 (95% confidence interval (CI): 0.83–0.89). The resultant sensitivity for PCT at a cut-off of 0.5 µg/L was 63.4% (95% CI: 56.3–70.0). Furthermore, specificity was 89.2% (95% CI: 86.3–91.7), the positive predictive value was 68.8% (95% CI: 62.9–74.2), and the negative predictive value was 86.7% (95% CI: 84.4–88.7). The early measurement of PCT in a patient population with elevated qSOFA score served as an effective tool for the early identification of sepsis in ED patients.

Estimation and correlation of procalcitonin in saliva and serum of chronic periodontitis patients before and after nonsurgical periodontal therapy: An analytical comparative study

Background

Procalcitonin (ProCT) is an emerging inflammatory biomarker in bacterial infections. Few studies have reported raising salivary ProCT in periodontitis patients. Hence, the study aims to analyze and correlate the changes in saliva and serum ProCT in periodontitis patients before and after nonsurgical periodontal therapy.

Materials and Methods

We have included 15 chronic periodontitis patients of mean age 41.8 ± 6.82 years who satisfy the inclusion criteria in the study. After saliva and serum collection, clinical parameters such as plaque index, gingival index, gingival bleeding index, probing pocket depth, and clinical attachment were recorded, and scaling and root debridement were performed. Reevaluation was done at 1- and 3-month interval. ProCT was estimated using the enzyme-linked immunosorbent assay.

Results

Salivary ProCT was significantly greater than its serum counterpart at baseline and 1 month after periodontal therapy (0.20 vs. 0.26, 0.13 vs. 0.14 ng/ml respectively). We noticed a significant reduction in salivary as well as serum ProCT (35% and 46%, respectively) 1 month after scaling and root debridement. A significant moderate positive correlation was found between paired observations of salivary and serum ProCT at baseline as well as after periodontal therapy (r = 0.61 and 0.7). A further reduction of salivary ProCT was noticed 3 months after nonsurgical therapy (0.11 ng/ml).

Conclusions

Serum ProCT significantly decreases with periodontal treatment, indicating the impact of periodontal therapy on systemic inflammation. Since salivary ProCT is positively correlated with serum ProCT, we can consider it as an alternative biomarker to its serum counterpart.

Development of magnetic particle-based chemiluminescence immunoassay for measurement of human procalcitonin in serum

BACKGROUND

Serum procalcitonin (PCT) has been recognized as a primary biomarker in bacterial infections, and monitoring its concentration could help to evaluate the prognosis of sepsis and guide the antibiotic administration. We aimed to establish a fast and accurate immunoassay for PCT quantitation.

METHODS

Our newly developed monoclonal antibodies (mAbs) against human PCT were preliminarily evaluated by enzyme-linked immunosorbent assay and then used to develop a chemiluminescence enzyme immunoassay (CLEIA). The proposed CLEIA was assessed in analytical performance and applied to measurement of serum PCT.

RESULTS

mAb 2D3 and mAb 8F6 were selected as capture and detection antibody respectively, due to the highest sensitivity for PCT detection with no cross reaction to calcitonin gene-related peptides. The proposed CLEIA based on mAb pair of 2D3/8F6-AP was characterized for a working range from 0.03 to 100 μg/L. An excellent correlation was observed between our proposed assay and the VIDAS BRAHMS PCT assay (r: 0.9825).

CONCLUSION

Our newly developed mAbs and CLEIA can serve as important diagnostic tools for measurement of human PCT in serum.

Procalcitonin utilization in the real world: An observational study of antibiotic prescribing practices

OBJECTIVES

This study aims to better understand and describe antibiotic prescribing practices and adherence to a procalcitonin (PCT)-guided algorithm in patients undergoing serum PCT testing in adult hospitalized patients.

METHODS

We performed an observational, retrospective study of 201 randomly selected patients who are aged ≥18 years, admitted to the general medicine floors or step-down unit between 1 January 2017 and 31 December 2017, and had serum PCT testing. Physician adherence to a PCT-guided algorithm was assessed through chart review.

RESULTS

We found an overall adherence of 64.7%. Adherence was highest for PCT values above 0.25 ng/mL (82.8% for 0.25-0.50 ng/mL and 83.6% for >0.50 ng/mL). Adherence was lower for PCT values less than 0.25 ng/mL (59% for <0.1 ng/mL and 38% for 0.1-0.24 ng/mL). Serial testing was performed in 10% of patients.

CONCLUSIONS

Hospital-based providers are more likely to overrule the algorithm and either initiate or continue antibiotics when guidelines encourage discontinuing antibiotics. These findings have important implications for antimicrobial stewardship and patient care and suggest that hospital-based providers may benefit from targeted didactics regarding the interpretation of the serum PCT assay.

Guidelines to Manage Community-Acquired Pneumonia

Few guidelines have greater acceptance than that for management of community-acquired pneumonia (CAP). Despite this, areas remain controversial, and new challenges continue to emerge. Current guidelines differ from those of northern European countries predominantly in need for macrolide combination with β-lactams for hospitalized, non-intensive care unit patients. A preponderance of evidence favors combination therapy. Challenges for current and future CAP guidelines include new antibiotic classes, emergence of viruses as major causes for CAP, new diagnostic modalities, alternative risk stratification for pathogens resistant to usual CAP antibiotics, and evidence-based management of severe CAP, including immunomodulatory therapy such as corticosteroids.

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.

Does procalcitonin have a role in the pathogenesis of nasal polyp?

PURPOSE

The aim of this study is to investigate serum and tissue procalcitonin (PCT) levels in patients with nasal polyps.

METHODS

The study was designed to be prospectively controlled and included 26 patients chronic rhinosinusitis with nasal polyp (CRSwNP) endoscopically diagnosed and as a control group 25 chronic rhinosinusitis without nasal polyp (CRSsNP). NP specimens, nasal mucosal tissue and venous blood samples of both groups were collected and PCT levels determined by Elisa method. The results were compared statistically.

RESULTS

Serum PCT values were 1319.5 pg/mL in the NP group and 818.8 pg/mL in the control group. The difference between the groups was statistically significant (p = 0.0001). In the NP group, the average PCT value of the polyp tissue was 1521.5 pg/gr, while the mean PCT value of the control group in the nasal mucosa was 414.6 pg/gr. There was a statistically significant difference between the groups (p = 0.0001). The tissue cut-off value of PCT 750 was significant [area under curve 0.940 (0.863-1.00)]. Serum PCT 950 cut-off value was significant [area under curve 0.860 (0.748-0.972)] activity (CI: 95%).

CONCLUSIONS

This is the first study of its kind to objectively examine PCT in the polyp and serum of CRSwNP patients. PCT may serve as a diagnostic biomarker in nasal polyps.

Efficacy and safety of antimicrobial de-escalation as a clinical strategy

INTRODUCTION

De-escalation is a widely recommended strategy in regard to guidelines, with an associated adherence to guidelines being around 50%. This review discusses data supporting de-escalation and possible obstacles for its implementation. Areas covered: Although it does not have a consensual definition, de-escalation consists of reducing the spectrum of empirical antimicrobial treatment based on the microbiological findings. Many observational studies have suggested that this strategy is likely safe and efficient for treating various types of infection. However, randomized controlled trials published as of now have not shown any improvement on the outcomes. Regarding the adverse effects of de-escalation on ecological pressure and multidrug resistance emergence, the data are contradictory. The implementation of new techniques, such as rapid diagnosis, can help guide clinicians. Expert opinion: De-escalation should be included as part of a large antibiotic stewardship program to balance the risk and benefit of each administration, and each physician prescribing antibiotics should be challenged for the quality of her/his prescription on a daily basis. In the future, one of our duties will involve determining whether a delay of antimicrobial treatment - making it possible to improve diagnostic performance and obtain the first laboratory results - is either safe or unsafe for our patients.

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.

Can serum Procalcitonin aid in the diagnosis of blood stream infection in patients on immunosuppressive medications?

BACKGROUND

Patients on immunosuppressive medications may not exhibit the systemic inflammatory response syndrome (SIRS) in the setting of bacterial infection. Our study examines the relationship between serum PCT levels and the odds of manifesting SIRS and BSI in patients on immunosuppressive medications and examines whether this relationship is altered from patients who are not on these medications. The diagnostic performance of Procalcitonin (PCT) detecting BSI in patients on immunosuppressive agents is compared to that in non-immunosuppressed patients.

METHODS

We tested the association between BSI, serum PCT levels, contemporaneous SIRS scores using logisitic regression in a dataset of 4279 patients. The diagnostic performance of these variables for detecting BSI was assessed.

RESULTS

In patients on immunosuppressive medications, multivariate logistic regression models demonstrate that while the serum PCT level is associated with BSI (OR: 2.48, p < .05) - the SIRS score is not. At any given serum PCT level, patients on immunosuppressive agents have lower odds of exhibiting SIRS despite having the same odds of having BSI as non-immunosuppressed patients. PCT (AUC: 0.68) performs better than SIRS (AUC: 0.52) in detecting the presence of BSI in patients on immunosuppressive medications. The diagnostic performance of PCT for detecting BSI in immunosuppressed patients is not significantly different from the non-immunosuppressed cohort.

CONCLUSIONS

As PCT levels rise, patients on immunosuppressive agents are less likely to mount a SIRS response, despite having a high probability of BSI. PCT might prove helpful in this setting as immunosuppressive agents do not alter the diagnostic performance of serum PCT in detecting BSI.

Checking procalcitonin suitability for prognosis and antimicrobial therapy monitoring in burn patients

Background

Due to greater infection susceptibility, sepsis is the main cause of death in burn patients. Quick diagnosis and patient stratification, early and appropriated antimicrobial therapy, and focus control are crucial for patients' survival. On the other hand, superfluous extension of therapy is associated with adverse events and arousal of microbial resistance. The use of biomarkers, necessarily coupled with close clinical examination, may predict outcomes, stratifying patients who need more intensive care, and monitor the efficacy of antimicrobial therapy, allowing faster de-escalation or stop, reducing the development of resistance and possibly the financial burden, without increasing mortality. The aim of this work is to check the suitability of procalcitonin (PCT) to fulfill these goals in a large sample of septic burn patients.

Methods

One hundred and one patients, with 15% or more of total body surface area (TBSA) burned, admitted from January 2011 to December 2014 at Coimbra Burns Unit (CBU), in Portugal were included in the sample. All patients had a diagnosis of sepsis, according to the American Burn Association (ABA) criteria. The sample was factored by survival (68 survivors and 33 non-survivors). The maximum value of PCT in each day was used for statistical analysis. Data were summarized by location measures (mean, median, minimum, maximum, quartiles) and dispersion measures (standard error and range measures). Statistical analysis was performed with SPSS© 23.0 IBM© for Windows©.

Results

There were statistically significant differences between PCT levels of patients from the survivor and non-survivor groups during the first and the last weeks of hospitalization as well as during the first week after sepsis suspicion, being slightly higher during this period. During the first 7 days of antimicrobial therapy, PCT was always higher in the non-survivor, still without reaching statistical significance, but when the analysis was extended till the 15th day, PCT increased significantly, rapidly, and steadily, denouncing therapy failure.

Conclusion

Despite being not an ideal biomarker, PCT proved to have good prognostic power in septic burn patients, paralleling the evolution of the infectious process and reflecting the efficacy of antimicrobial therapy, and the inclusion of its serial dosing may be advised to reinforce antimicrobial stewardship programs at burn units; meanwhile, more accurate approaches are not available.

A meta-analysis to assess usefulness of procalcitonin-guided antibiotic usage for decision making

Background & objectives:

Development of antibacterial resistance and its association with antibiotic overuse makes it necessary to identify a specific and sensitive biomarker for the diagnosis of bacterial infection and guiding antibiotic therapy. Procalcitonin (PCT), as a sepsis biomarker, may play a role in guiding antibiotics treatment in hospital settings. The aim of the current meta-analysis was to analyze the utility of PCT on various outcomes of interest in inpatients.

Methods:

Different databases were searched for randomized controlled trials comparing PCT-guided therapy with standard therapy in admitted patients with bacterial infections. Twenty six articles were found suitable for full text search and of these, 16 studies were considered finally for data extraction.

Results:

There were no significant differences found in total mortality [pooled odds ratio (OR) 1.04, 95% confidence interval (CI) 0.89-1.22, P=0.63], 28-day mortality (pooled OR 0.97, 95% CI 0.80-1.19, P=0.79), need of Intensive Care Unit admission (OR=0.80, 95% CI 0.59-1.09, P=0.16) and duration of stay in hospital (pooled mean difference −0.01, 95% CI −0.50-0.49, P=0.98) between treatment and control groups. PCT-guided treatment significantly decreased the duration of antibiotic treatment (pooled mean difference −2.79, 95% CI −3.52-−2.06, P<0.00001).

Interpretation & conclusions:

PCT-guided therapy significantly decreased antibiotics exposure and thus treatment cost. However, the hard endpoints did not demonstrate any significant benefits, possibly due to low power to detect differences and/or the presence of comorbidities.

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.

Procalcitonin, erythrocyte sedimentation rate and C-reactive protein in acute pulmonary exacerbations of cystic fibrosis

INTRODUCTION

Acute pulmonary exacerbations of cystic fibrosis (APECF) are a leading cause of morbidity and mortality among patients with cystic fibrosis (CF). APECF require frequent administration of antibiotics and subsequently lead to development of resistant organisms.

OBJECTIVES

The aim of this study was to identify inflammatory markers that may be help identify need for antibiotics and exacerbation as well as predict risk of exacerbations.

METHODS

A total of 17 patients were enrolled, and baseline erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and procalcitonin levels were obtained in addition to obtaining these levels during admissions for APECF.

RESULTS

A total of 28 APECF were recorded. ESR and CRP significantly increased during exacerbation (P < .01 for both). Procalcitonin did not increase during exacerbations. Baseline elevations in ESR and CRP increased risk of an exacerbation (RR = 2.3 and 4.5, respectively).

CONCLUSIONS

ESR and CRP are useful markers for CF exacerbations, as levels rise with exacerbations. Baseline elevations in ESR and CRP were noted to show an increased risk for CF exacerbations. Procalcitonin, in contrast, is not a useful inflammatory marker.

Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016

OBJECTIVE

To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012."

DESIGN

A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development.

METHODS

The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable.

RESULTS

The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions.

CONCLUSIONS

Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.

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.

Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016

OBJECTIVE

To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012".

DESIGN

A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development.

METHODS

The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable.

RESULTS

The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions.

CONCLUSIONS

Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.

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.

Salivary and serum procalcitonin and C-reactive protein as biomarkers of periodontitis in United States veterans with osteoarthritis or rheumatoid arthritis

Serum procalcitonin (ProCT) is elevated in response to bacterial infections, whereas high sensitivity C-reactive protein (hsCRP) is a nonspecific inflammatory marker that is increased by excess adipose tissue. We examined the efficacy of ProCT and hsCRP as biomarkers of periodontitis in the saliva and serum of patients with arthritis, which is characterized by variable levels of systemic inflammation that potentially can confound the interpretation of inflammatory biomarkers. Blood and unstimulated whole saliva were collected from 33 patients with rheumatoid arthritis (RA) and 50 with osteoarthritis (OA). Periodontal status was assessed by full mouth examination and patients were categorized as having no/mild, moderate or severe periodontitis by standard parameters. Salivary and serum ProCT and hsCRP concentrations were compared. BMI, diabetes, anti-inflammatory medications and smoking status were ascertained from the patient records. Differences between OA and RA in proportionate numbers of patients were compared for race, gender, diabetes, adiposity and smoking status. Serum ProCT was significantly higher in arthritis patients with moderate to severe and severe periodontitis compared with no/mild periodontitis patients. There were no significant differences in salivary ProCT or salivary or serum hsCRP in RA patients related to periodontitis category. Most of the OA and RA patients were middle aged or older, 28.9% were diabetic, 78.3% were overweight or obese, and slightly more than half were either current or past smokers. The OA and RA groups differed by race, but not gender; blacks and males were predominant in both groups. The OA and RA groups did not differ in terms of controlled or uncontrolled diabetes, smoking status or BMI. The RA patients had been prescribed more anti-inflammatory medication than the OA patients. Our results demonstrate that circulating ProCT is a more discriminative biomarker for periodontitis than serum hsCRP in patients with underlying arthritis. Any elevation in salivary and serum hsCRP due to periodontitis apparently was overshadowed by differences among these patients in factors that influence CRP, such as the extent of inflammation between RA and OA, the extent of adipose tissue, the use of anti- inflammatory medications and smoking status. Although our study showed no differences in salivary ProCT related to severity of periodontitis, this biomarker also may be useful with further refinement.

Effect of Procalcitonin Testing on Health-care Utilization and Costs in Critically Ill Patients in the United States

BACKGROUND

There is a growing use of procalcitonin (PCT) to facilitate the diagnosis and management of severe sepsis. We investigated the impact of one to two PCT determinations on ICU day 1 on health-care utilization and cost in a large research database.

METHODS

A retrospective, propensity score-matched multivariable analysis was performed on the Premier Healthcare Database for patients admitted to the ICU with one to two PCT evaluations on day 1 of ICU admission vs patients who did not have PCT testing.

RESULTS

A total of 33,569 PCT-managed patients were compared with 98,543 propensity score-matched non-PCT patients. In multivariable regression analysis, PCT utilization was associated with significantly decreased total length of stay (11.6 days [95% CI, 11.4 to 11.7] vs 12.7 days [95% CI, 12.6 to 12.8]; 95% CI for difference, 1 to 1.3; P < .001) and ICU length of stay (5.1 days [95% CI, 5.1 to 5.2] vs 5.3 days [95% CI, 5.3 to 5.4]; 95% CI for difference, 0.1 to 0.3; P < .03), and lower hospital costs ($30,454 [95% CI, 29,968 to 31,033] vs $33,213 [95% CI, 32,964 to 33,556); 95% CI for difference, 2,159 to 3,321; P < .001). There was significantly less total antibiotic exposure (16.2 days [95% CI, 16.1 to 16.5] vs 16.9 days [95% CI, 16.8 to 17.1]; 95% CI for difference, -0.9 to 0.4; P = .006) in PCT-managed patients. Patients in the PCT group were more likely to be discharged to home (44.1% [95% CI, 43.7 to 44.6] vs 41.3% [95% CI, 41 to 41.6]; 95% CI for difference, 2.3 to 3.3; P = .006). Mortality was not different in an analysis including the 96% of patients who had an independent measure of mortality risk available (19.1% [95% CI, 18.7 to 19.4] vs 19.1% [95% CI, 18.9 to 19.3]; 95% CI for difference, -0.5 to 0.4; P = .93).

CONCLUSIONS

Use of PCT testing on the first day of ICU admission was associated with significantly lower hospital and ICU lengths of stay, as well as decreased total, ICU, and pharmacy cost of care. Further elucidation of clinical outcomes requires additional data.

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.

Assessment of Diagnostic and Prognostic Role of Copeptin in the Clinical Setting of Sepsis

The diagnostic and prognostic usefulness of copeptin were evaluated in septic patients, as compared to procalcitonin assessment. In this single centre and observational study 105 patients were enrolled: 24 with sepsis, 25 with severe sepsis, 15 with septic shock, and 41 controls, divided in two subgroups (15 patients with gastrointestinal bleeding and 26 with suspected SIRS secondary to trauma, acute coronary syndrome, and pulmonary embolism). Biomarkers were determined at the first medical evaluation and thereafter 24, 48, and 72 hours after admission. Definitive diagnosis and in-hospital survival rates at 30 days were obtained through analysis of medical records. At entry, copeptin proved to be able to distinguish cases from controls and also sepsis group from septic shock group, while procalcitonin could distinguish also severe sepsis from septic shock group. Areas under the ROC curve for copeptin and procalcitonin were 0.845 and 0.861, respectively. Noteworthy, patients with copeptin concentrations higher than the threshold value (23.2 pmol/L), calculated from the ROC curve, at admission presented higher 30-day mortality. No significant differences were found in copeptin temporal profile among different subgroups. Copeptin showed promising diagnostic and prognostic role in the management of sepsis, together with its possible role in monitoring the response to treatment.

Procalcitonin: Is This the Promised Biomarker for Critically Ill Patients?

Objective Procalcitonin (PCT) has been increasingly used in the critical care setting to determine the presence of bacterial infection and also to guide antibiotic therapy. We reviewed PCT's physiologic role, as well as its clinical utility for the management of pediatric critically ill patients. Findings PCT is a precursor of the hormone calcitonin. Its production is induced by inflammatory conditions, especially bacterial infections. Literature shows that PCT is a moderately reliable diagnostic test for severe bacterial infection in children. Synthesis of available adult studies suggests that the use of PCT-based algorithms to support medical decision making reduces antibiotic exposure without compromising safety in critically ill patients. However, no study has addressed the usefulness and safety of PCT to guide antibiotic therapy in severely ill children. In pediatric patients with acute lower respiratory tract infections, the use of PCT-based algorithms also led to a safe decrease in antibiotic treatment duration. Conclusion PCT has demonstrated clinical utility in the pediatric critical care setting when used for the diagnosis of bacterial infections and to guide antibiotic use in children with acute lower respiratory tract infections. However, more research is needed in critically ill children to determine the utility of PCT-driven antibiotic therapy in this population.

The use and risks of antibiotics in critically ill patients

INTRODUCTION

The altered pathophysiology in critically ill patients presents a unique challenge in both the diagnosis of infection and the appropriate prescription of antibiotics. In this context, the importance of effective and timely treatment needs to be weighed against the individual and community harms associated with antibiotic collateral damage and antibiotic resistance.

AREAS COVERED

We evaluate the principles of antibiotic use in critically ill patients, including dose optimisation, use of combination antibiotic therapy, therapeutic drug monitoring, appropriate antibiotic therapy duration, de-escalation, and utilisation of sepsis biomarkers. We also describe the potential risks associated with antibiotic therapy including antibiotic resistance, delayed treatment, treatment failure, and collateral damage.

EXPERT OPINION

Prescribing teams must be aware of the impact of critical illness on their patients and tailor antibiotic therapy appropriately to prevent the significant harms associated with suboptimal antibiotic administration.

Procalcitonin cannot be used as a biomarker of infection in heart surgery patients with acute kidney injury

PURPOSE

We intended to assess how acute kidney injuy impacts on procalcitonin levels in cardiac surgery patients, with or without infection, and whether procalcitonin might be used as a biomarker of infection in acute kidney injuy.

MATERIAL AND METHODS

A case-control study was designed which included patients that had had cardiac surgery between January 2011 and January 2015. Every patient developing severe sepsis or septic shock (n = 122; 5.5%) was enrolled. In addition, consecutive cardiac surgery patients during 2013 developing systemic inflammatory response syndrome (n = 318) were enrolled. Those recruited 440 patients were divided into 2 groups, according to renal function.

RESULTS

Median procalcitonin levels were significantly higher during the 10 postoperative days in the acute kidney injury patients. Regression analysis showed that postoperatory day, creatinine, white blood cells and infection were significantly (P < .0001) associated to serum procalcitonin level. In patients with creatinine ≥2, median procalcitonin levels were similar in infected and non-infected patients. Only when creatinine was less than 2 mg/L, the median procalcitonin levels were significantly higher in patients with infection, as compared to those with no infection.

CONCLUSIONS

In acute kidney injuy patients, high procalcitonin levels are a marker of acute kidney injuy but will not be able to differentiate infected from non-infected patients.

Is procalcitonin-guided antimicrobial use cost-effective in adult patients with suspected bacterial infection and sepsis?

OBJECTIVE

Procalcitonin has emerged as a promising biomarker of bacterial infection. Published literature demonstrates that use of procalcitonin testing and an associated treatment pathway reduces duration of antibiotic therapy without impacting mortality. The objective of this study was to determine the financial impact of utilizing a procalcitonin-guided treatment algorithm in hospitalized patients with sepsis.

DESIGN

Cost-minimization and cost-utility analysis.

PATIENTS

Hypothetical cohort of adult ICU patients with suspected bacterial infection and sepsis.

METHODS

Utilizing published clinical and economic data, a decision analytic model was developed from the U.S. hospital perspective. Effectiveness and utility measures were defined using cost-per-clinical episode and cost per quality-adjusted life years (QALYs). Upper and lower sensitivity ranges were determined for all inputs. Univariate and probabilistic sensitivity analyses assessed the robustness of our model and variables. Incremental cost-effectiveness ratios (ICERs) were calculated and compared to predetermined willingness-to-pay thresholds.

RESULTS

Base-case results predicted the use of a procalcitonin-guided treatment algorithm dominated standard care with improved quality (0.0002 QALYs) and decreased overall treatment costs ($65). The model was sensitive to a number of key variables that had the potential to impact results, including algorithm adherence (<42.3%), number and cost of procalcitonin tests ordered (≥9 and >$46), days of antimicrobial reduction (<1.6 d), incidence of nephrotoxicity and rate of nephrotoxicity reduction.

CONCLUSION

The combination of procalcitonin testing with an evidence-based treatment algorithm may improve patients' quality of life while decreasing costs in ICU patients with suspected bacterial infection and sepsis; however, results were highly dependent on a number of variables and assumptions.

Procalcitonin-based algorithms to initiate or stop antibiotic therapy in critically ill patients: Is it time to rethink our strategy?

Procalcitonin (PCT)-based antibiotic management algorithms for critically ill patients have been described in the literature. An evaluation of the available evidence demonstrates that studies have utilised PCT in various clinical scenarios: for the initiation of antimicrobials; for cessation or de-escalation of antimicrobials; or for the combination of both strategies. Current PCT reviews and meta-analyses have combined studies from all different clinical scenarios. However, there may be significant variations in algorithm compliance and clinical outcomes associated with the use of PCT in these different strategies. As such, the current review focused on separating out the studies utilising PCT in the critically ill population for different treatment strategies. Based on this review, we would recommend that PCT should not be used as the sole deciding factor for the initiation of antimicrobials. As such, PCT should not be obtained in patients who do not exhibit evidence of infection. In patients who do have signs of infection and antimicrobials have been initiated, a strategy that utilises PCT for the discontinuation or de-escalation of antimicrobials is likely to decrease the duration of treatment without adversely affecting outcome.

Multicenter comparison of automated procalcitonin immunoassays

Objectives

A multicenter study to compare results of BRAHMS Kryptor PCT with those obtained using four BRAHMS-partnered procalcitonin (PCT) automated immunoassays (DiaSorin Liaison, BioMérieux Vidas, Roche Cobas E601 and Siemens Advia Centaur) and the Diazyme immunotubidimetric assay implemented on four clinical chemistry platforms (Abbott Architect c16000, Siemens Advia 2400, Roche Cobas C501 and Beckman Coulter AU5800).

Design and methods

One hundred serum samples from in-patients with PCT values between 0.10 and 58.7 ng/mL were divided into aliquots and tested with the nine different reagents and analyzers. BRAHMS PCT Kryptor results were used as reference.

Results

Compared to BRAHMS PCT Kryptor, significant differences in results were observed on Vidas, Advia Centaur, Architect, Cobas C501 and AU5800. However, the correlation coeffiecients (r) with BRAHMS PCT Kryptor were between 0.899 and 0.988. The mean bias was less than ±1.02 ng/mL, except for Vidas (2.70 ng/mL). The agreement at three clinically relevant cut-offs was optimal: between 83–98% at 0.50 ng/mL, 90–97% at 2.0 ng/mL, and 98% at 10 ng/mL. The comparison of Diazyme PCT across the four clinical chemistry analyzers yielded high correlation coefficients (r between 0.952 and 0.976), a mean bias less than ±0.9 ng/mL, acceptable agreement at 0.5 ng/mL (>82%), and high concordance at the 2.0 ng/mL (>97%) and 10 ng/mL (>98%) cut-offs.

Conclusions

The methods and applications evaluated in this multicenter study are aligned with BRAHMS PCT Kryptor and can be used for predicting the risk of progression to systemic inflammation in patients with bacterial infections using the conventional PCT diagnostic thresholds.

What was old is new again: using the host response to diagnose infectious disease

A century of advances in infectious disease diagnosis and treatment changed the face of medicine. However, challenges continue to develop including multi-drug resistance, globalization that increases pandemic risks and high mortality from severe infections. These challenges can be mitigated through improved diagnostics, focusing on both pathogen discovery and the host response. Here, we review how 'omics' technologies improve sepsis diagnosis, early pathogen identification and personalize therapy. Such host response diagnostics are possible due to the confluence of advanced laboratory techniques (e.g., transcriptomics, metabolomics, proteomics) along with advanced mathematical modeling such as machine learning techniques. The road ahead is promising, but obstacles remain before the impact of such advanced diagnostic modalities is felt at the bedside.

Serum procalcitonin levels in patients with primary pulmonary coccidioidomycosis

RATIONALE

The serum procalcitonin assay has emerged as a promising biomarker to distinguish between bacterial and viral respiratory tract infections but has not been used to differentiate coccidioidomycosis from bacterial infection. A correlation between procalcitonin serum levels and coccidioidomycosis has never been reported.

OBJECTIVE

To determine any association between serum procalcitonin levels and primary pulmonary coccidioidomycosis.

METHODS

We identified and enrolled 20 immunocompetent patients with symptomatic primary pulmonary coccidioidomycosis of < 8 weeks' duration and performed a one-time procalcitonin assay, with a cutoff of < 0.25 μg/L indicating a nonbacterial infection.

MEASUREMENTS AND MAIN RESULTS

Nineteen of 20 patients (95%) had serum procalcitonin of < 0.25 μg/L. The median procalcitonin level was 0.05 μg/L (range, < 0.05-0.87 μg/L; interquartile range, 0.05-0.05 μg/L). Sixteen of 20 patients (80%) had undetectable procalcitonin of < 0.05 μg/L. The four patients with detectable procalcitonin had a median value of 0.2 μg/L (range, 0.09-0.87 μg/L).

CONCLUSIONS

In this pilot study, procalcitonin was not elevated in immunocompetent patients with primary pulmonary coccidioidomycosis at a median of 32 days after symptom onset. Larger prospective studies are needed to confirm this finding.

Clinical and Cost-Effectiveness of Procalcitonin Test for Prodromal Meningococcal Disease-A Meta-Analysis

Background

Despite vaccines and improved medical intensive care, clinicians must continue to be vigilant of possible Meningococcal Disease in children. The objective was to establish if the procalcitonin test was a cost-effective adjunct for prodromal Meningococcal Disease in children presenting at emergency department with fever without source.

Methods and Findings

Data to evaluate procalcitonin, C-reactive protein and white cell count tests as indicators of Meningococcal Disease were collected from six independent studies identified through a systematic literature search, applying PRISMA guidelines. The data included 881 children with fever without source in developed countries.The optimal cut-off value for the procalcitonin, C-reactive protein and white cell count tests, each as an indicator of Meningococcal Disease, was determined. Summary Receiver Operator Curve analysis determined the overall diagnostic performance of each test with 95% confidence intervals. A decision analytic model was designed to reflect realistic clinical pathways for a child presenting with fever without source by comparing two diagnostic strategies: standard testing using combined C-reactive protein and white cell count tests compared to standard testing plus procalcitonin test. The costs of each of the four diagnosis groups (true positive, false negative, true negative and false positive) were assessed from a National Health Service payer perspective. The procalcitonin test was more accurate (sensitivity=0.89, 95%CI=0.76-0.96; specificity=0.74, 95%CI=0.4-0.92) for early Meningococcal Disease compared to standard testing alone (sensitivity=0.47, 95%CI=0.32-0.62; specificity=0.8, 95% CI=0.64-0.9). Decision analytic model outcomes indicated that the incremental cost effectiveness ratio for the base case was £-8,137.25 (US $ -13,371.94) per correctly treated patient.

Conclusions

Procalcitonin plus standard recommended tests, improved the discriminatory ability for fatal Meningococcal Disease and was more cost-effective; it was also a superior biomarker in infants. Further research is recommended for point-of-care procalcitonin testing and Markov modelling to incorporate cost per QALY with a life-time model.

Procalcitonin-Guided Antibiotic Therapy Duration in Critically Ill Adults

Procalcitonin is a promising biomarker for antibiotic therapy because its levels rise and fall quickly with bacterial infections. A multi-database literature search was reviewed with 3 primary prospective randomized control trials used in further analysis. The results indicated that a procalcitonin-guided antibiotic protocol reduces the number of days a patient has to take antibiotics while having no effect on mortality when compared with control groups. Short-term studies did not show a difference in the intensive care unit length of stay, infection relapse rate, super-infection rate, or multidrug-resistant bacteria rate between the procalcitonin-protocol and control group. Because procalcitonin-guided antibiotic therapy has been shown to reduce the duration of treatment with antibiotics in critically ill patients without worsening the mortality rate or other outcomes, the implementation of a procalcitonin-guided antibiotic therapy should be considered for patients with proven or highly suspected bacterial infections in the intensive care unit.

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.