Procalcitonin to initiate or discontinue antibiotics in acute respiratory tract infections

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.

Differentiating viral and bacterial infections: A machine learning model based on routine blood test values

The growing threat of antibiotic resistance necessitates accurate differentiation between bacterial and viral infections for proper antibiotic administration. In this study, a Virus vs. Bacteria machine learning model was developed to distinguish between these infection types using 16 routine blood test results, C-reactive protein concentration (CRP), biological sex, and age. With a dataset of 44,120 cases from a single medical center, the model achieved an accuracy of 82.2 %, a sensitivity of 79.7 %, a specificity of 84.5 %, a Brier score of 0.129, and an area under the ROC curve (AUC) of 0.905, outperforming a CRP-based decision rule. Notably, the machine learning model enhanced accuracy within the CRP range of 10-40 mg/L, a range where CRP alone is less informative. These results highlight the advantage of integrating multiple blood parameters in diagnostics. The "Virus vs. Bacteria" model paves the way for advanced diagnostic tools, leveraging machine learning to optimize infection management.

A high α1-antitrypsin/interleukin-10 ratio predicts bacterial pneumonia in adults with community-acquired pneumonia: a prospective cohort study

BACKGROUND

Current microbiological tests fail to identify the causative microorganism in more than half of all pneumonia cases. We explored biomarkers that could be used for differentiating between bacterial and viral pneumonia in patients with community-acquired pneumonia (CAP).

METHODS

In this prospective cohort study conducted in Japan, data obtained from adult patients with bacterial pneumonia, including bacterial and viral coinfections (bacterial pneumonia [BP] group), and purely viral pneumonia (VP group) at diagnosis were analyzed using multivariate logistic regression analysis to identify predictors of bacterial pneumonia. Furthermore, a decision tree was developed using the predictors.

RESULTS

A total of 210 patients were analyzed. The BP and VP groups comprised 108 and 18 patients, respectively. The other 84 patients had no identified causative microorganism. The two groups shared similar characteristics, including disease severity; however, a significant difference (p < 0.05) was observed between the two groups regarding sputum type; sputum volume score; neutrophil counts; and serum levels of interleukin (IL)-8, IL-10, and α1-antitrypsin (AAT). Sputum volume score (p < 0.001), IL-10 (p < 0.001), and AAT (p = 0.008) were ultimately identified as predictors of BP. The area under the curve for these three variables on the receiver operating characteristic (ROC) curve was 0.927 (95% confidence interval [CI]: 0.881-0.974). The ROC curve for sputum volume score and an AAT/IL-10 ratio showed a diagnostic cutoff of 1 + and 65, respectively. Logistic regression analysis using dichotomized variables at the cutoff values showed that the odds ratios for the diagnosis of BP were 10.4 (95% CI: 2.2-50.2) for sputum volume score (absence vs. presence) and 19.8 (95% CI: 4.7-83.2) for AAT/IL-10 ratio (< 65 vs. ≥ 65).

CONCLUSIONS

Considering that obtaining a definitive etiologic diagnosis with the current testing methods is difficult and time consuming, a decision tree with two predictors, namely sputum volume and the AAT/IL-10 ratio, can be useful in predicting BP among patients diagnosed with CAP and facilitating the appropriate use of antibiotics.

TRIAL REGISTRATION

UMIN000034673 registered on November 29, 2018.

Procalcitonin-guided antibiotic therapy may shorten length of treatment and may improve survival-a systematic review and meta-analysis

BACKGROUND

Appropriate antibiotic (AB) therapy remains a challenge in the intensive care unit (ICU). Procalcitonin (PCT)-guided AB stewardship could help optimize AB treatment and decrease AB-related adverse effects, but firm evidence is still lacking. Our aim was to compare the effects of PCT-guided AB therapy with standard of care (SOC) in critically ill patients.

METHODS

We searched databases CENTRAL, Embase and Medline. We included randomized controlled trials (RCTs) comparing PCT-guided AB therapy (PCT group) with SOC reporting on length of AB therapy, mortality, recurrent and secondary infection, ICU length of stay (LOS), hospital LOS or healthcare costs. Due to recent changes in sepsis definitions, subgroup analyses were performed in studies applying the Sepsis-3 definition. In the statistical analysis, a random-effects model was used to pool effect sizes.

RESULTS

We included 26 RCTs (n = 9048 patients) in the quantitative analysis. In comparison with SOC, length of AB therapy was significantly shorter in the PCT group (MD - 1.79 days, 95% CI: -2.65, - 0.92) and was associated with a significantly lower 28-day mortality (OR 0.84, 95% CI: 0.74, 0.95). In Sepsis-3 patients, mortality benefit was more pronounced (OR 0.46 95% CI: 0.27, 0.79). Odds of recurrent infection were significantly higher in the PCT group (OR 1.36, 95% CI: 1.10, 1.68), but there was no significant difference in the odds of secondary infection (OR 0.81, 95% CI: 0.54, 1.21), ICU and hospital length of stay (MD - 0.67 days 95% CI: - 1.76, 0.41 and MD - 1.23 days, 95% CI: - 3.13, 0.67, respectively).

CONCLUSIONS

PCT-guided AB therapy may be associated with reduced AB use, lower 28-day mortality but higher infection recurrence, with similar ICU and hospital length of stay. Our results render the need for better designed studies investigating the role of PCT-guided AB stewardship in critically ill patients.

Choosing Wisely interventions to reduce antibiotic overuse in the safety net

OBJECTIVES

Physician pay-for-performance (P4P) programs frequently target inappropriate antibiotics. Yet little is known about P4P programs' effects on antibiotic prescribing among safety-net populations at risk for unintended harms from reducing care. We evaluated effects of P4P-motivated interventions to reduce antibiotic prescriptions for safety-net patients with acute respiratory tract infections (ARTIs).

STUDY DESIGN

Interrupted time series.

METHODS

A nonrandomized intervention (5/28/2015-2/1/2018) was conducted at 2 large academic safety-net hospitals: Los Angeles County+University of Southern California (LAC+USC) and Olive View-UCLA (OV-UCLA). In response to California's 2016 P4P program to reduce antibiotics for acute bronchitis, 5 staggered Choosing Wisely-based interventions were launched in combination: audit and feedback, clinician education, suggested alternatives, procalcitonin, and public commitment. We also assessed 5 unintended effects: reductions in Healthcare Effectiveness Data and Information Set (HEDIS)-appropriate prescribing, diagnosis shifting, substituting antibiotics with steroids, increasing antibiotics for ARTIs not penalized by the P4P program, and inappropriate withholding of antibiotics.

RESULTS

Among 3583 consecutive patients with ARTIs, mean antibiotic prescribing rates for ARTIs decreased from 35.9% to 22.9% (odds ratio [OR], 0.60; 95% CI, 0.39-0.93) at LAC+USC and from 48.7% to 27.3% (OR, 0.81; 95% CI, 0.70-0.93) at OV-UCLA after the intervention. HEDIS-inappropriate prescribing rates decreased from 28.9% to 19.7% (OR, 0.69; 95% CI, 0.39-1.21) at LAC+USC and from 40.9% to 12.5% (OR, 0.72; 95% CI, 0.59-0.88) at OV-UCLA. There was no evidence of unintended consequences.

CONCLUSIONS

These real-world multicomponent interventions responding to P4P incentives were associated with substantial reductions in antibiotic prescriptions for ARTIs in 2 safety-net health systems without unintended harms.

[Preclinical early detection and diagnosis of sepsis - step by step]

Because of very unspecific sepsis symptoms, early recognition of the emergency sepsis is difficult. If the disease is recognized in time it is possible to initiate diagnosis and treatment quickly. Rapid treatment of sepsis leads to lower mortality and less severe long-term consequences. Early detection is therefore of central importance in the diagnostic and therapeutic process, also in the outpatient setting.

Procalcitonin-Guided Antibiotic Prescription in Patients With COVID-19: A Multicenter Observational Cohort Study

BACKGROUND

Despite the low rate of bacterial coinfection, antibiotics are very commonly prescribed in hospitalized patients with COVID-19.

RESEARCH QUESTION

Does the use of a procalcitonin (PCT)-guided antibiotic protocol safely reduce the use of antibiotics in patients with a COVID-19 infection?

STUDY DESIGN AND METHODS

In this multicenter cohort, three groups of patients with COVID-19 were compared in terms of antibiotic consumption, namely one group treated based on a PCT-algorithm in one hospital (n = 216) and two control groups, consisting of patients from the same hospital (n = 57) and of patients from three similar hospitals (n = 486) without PCT measurements during the same period. The primary end point was antibiotic prescription in the first week of admission.

RESULTS

Antibiotic prescription during the first 7 days was 26.8% in the PCT group, 43.9% in the non-PCT group in the same hospital, and 44.7% in the non-PCT group in other hospitals. Patients in the PCT group had lower odds of receiving antibiotics in the first 7 days of admission (OR, 0.33; 95% CI, 0.16-0.66 compared with the same hospital; OR, 0.42; 95% CI, 0.28-0.62 compared with the other hospitals). The proportion of patients receiving antibiotic prescription during the total admission was 35.2%, 43.9%, and 54.5%, respectively. The PCT group had lower odds of receiving antibiotics during the total admission only when compared with the other hospitals (OR, 0.23; 95% CI, 0.08-0.63). There were no significant differences in other secondary end points, except for readmission in the PCT group vs the other hospitals group.

INTERPRETATION

PCT-guided antibiotic prescription reduces antibiotic prescription rates in hospitalized patients with COVID-19, without major safety concerns.

Impact of Point-of-Care Rapid Diagnostic Tests on Antibiotic Prescription Among Patients Aged <18 Years in Primary Healthcare Settings in 2 Peri-Urban Districts in Ghana: Randomized Controlled Trial Results

BACKGROUND

Inappropriate antibiotic prescriptions are a known driver of antimicrobial resistance in settings with limited diagnostic capacity. This study aimed to assess the impact of diagnostic algorithms incorporating rapid diagnostic tests on clinical outcomes and antibiotic prescriptions compared with standard-of-care practices, of acute febrile illness cases at outpatient clinics in Shai-Osudoku and Prampram districts in Ghana.

METHODS

This was an open-label, centrally randomized controlled trial in 4 health facilities. Participants aged 6 months to <18 years of both sexes with acute febrile illness were randomized to receive a package of interventions to guide antibiotic prescriptions or standard care. Clinical outcomes were assessed on day 7.

RESULTS

In total, 1512 patients were randomized to either the intervention (n = 761) or control (n = 751) group. Majority were children aged <5 years (1154 of 1512, 76.3%) and male (809 of 1512, 53.5%). There was 11% relative risk reduction of antibiotic prescription in intervention group (RR, 0.89; 95% CI, .79 to 1.01); 14% in children aged <5 years (RR, 0.86; 95% CI, .75 to .98), 15% in nonmalaria patients (RR, 0.85; 95% CI, .75 to .96), and 16% in patients with respiratory symptoms (RR, 0.84; 95% CI, .73 to .96). Almost all participants had favorable outcomes (759 of 761, 99.7% vs 747 of 751, 99.4%).

CONCLUSIONS

In low- and middle-income countries, the combination of point-of-care diagnostics, diagnostic algorithms, and communication training can be used at the primary healthcare level to reduce antibiotic prescriptions among children with acute febrile illness, patients with nonmalarial fevers, and respiratory symptoms.

CLINICAL TRIALS REGISTRATION

NCT04081051.

The potential clinical value of pairing procalcitonin and lung ultrasonography to guide antibiotic therapy in patients with community-acquired pneumonia: a narrative review

INTRODUCTION

Lower respiratory tract infections (LRTIs) are among the most frequent infections and are prone to inappropriate antibiotic treatments. This results from a limited accuracy of diagnostic tools in identifying bacterial pneumonia. Lung ultrasound (LUS) has excellent sensitivity and specificity in diagnosing pneumonia. Additionally, elevated procalcitonin (PCT) levels correlate with an increased likelihood of bacterial infection. LUS and PCT appear to be complementary in identifying patients with bacterial pneumonia who are likely to benefit from antibiotics.

AREAS COVERED

This narrative review aims to summarize the current evidence for LUS to diagnose pneumonia, for PCT to guide antibiotic therapy and the clinical value of pairing both tools.

EXPERT OPINION

LUS has excellent diagnostic accuracy for pneumonia in different settings, regardless of the examiner's experience. PCT guidance safely reduces antibiotic prescription in LRTIs. The combination of both tools has demonstrated an enhanced accuracy in the diagnosis of pneumonia, including CAP in the ED and VAP in the ICU, but randomized controlled studies need to validate the clinical impact of a combined approach.

ERS/ESICM/ESCMID/ALAT guidelines for the management of severe community-acquired pneumonia

PURPOSE

Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and whilst European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP.

METHODS

The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations.

RESULTS

Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions.

CONCLUSIONS

In these international guidelines, ERS, ESICM, ESCMID, and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment, and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.

Antibiotic stewardship in the ICU: time to shift into overdrive

Antibiotic resistance is a major health problem and will be probably one of the leading causes of deaths in the coming years. One of the most effective ways to fight against resistance is to decrease antibiotic consumption. Intensive care units (ICUs) are places where antibiotics are widely prescribed, and where multidrug-resistant pathogens are frequently encountered. However, ICU physicians may have opportunities to decrease antibiotics consumption and to apply antimicrobial stewardship programs. The main measures that may be implemented include refraining from immediate prescription of antibiotics when infection is suspected (except in patients with shock, where immediate administration of antibiotics is essential); limiting empiric broad-spectrum antibiotics (including anti-MRSA antibiotics) in patients without risk factors for multidrug-resistant pathogens; switching to monotherapy instead of combination therapy and narrowing spectrum when culture and susceptibility tests results are available; limiting the use of carbapenems to extended-spectrum beta-lactamase-producing Enterobacteriaceae, and new beta-lactams to difficult-to-treat pathogen (when these news beta-lactams are the only available option); and shortening the duration of antimicrobial treatment, the use of procalcitonin being one tool to attain this goal. Antimicrobial stewardship programs should combine these measures rather than applying a single one. ICUs and ICU physicians should be at the frontline for developing antimicrobial stewardship programs.

ERS/ESICM/ESCMID/ALAT guidelines for the management of severe community-acquired pneumonia

BACKGROUND

Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and while European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP.

MATERIALS AND METHODOLOGY

The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations.

RESULTS

Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions.

CONCLUSIONS

In these international guidelines, ERS, ESICM, ESCMID and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.

Biomarkers for risk stratification and antibiotic stewardship in elderly patients

PURPOSE

Optimal treatment of infections in the elderly patients population is challenging because clinical symptoms and signs may be less specific potentially resulting in both, over- and undertreatment. Elderly patients also have a less pronounced immune response to infection, which may influence kinetics of biomarkers of infection.

METHODS

Within a group of experts, we critically reviewed the current literature regarding biomarkers for risk stratification and antibiotic stewardship in elderly patients with emphasis on procalcitonin (PCT).

RESULTS

The expert group agreed that there is strong evidence that the elderly patient population is particularly vulnerable for infections and due to ambiguity of clinical signs and parameters in the elderly, there is considerable risk for undertreatment. At the same time, however, this group of patients is particularly vulnerable for off-target effects from antibiotic treatment and limiting the use of antibiotics is therefore important. The use of infection markers including PCT to guide individual treatment decisions has thus particular appeal in geriatric patients. For the elderly, there is evidence that PCT is a valuable biomarker for assessing the risk of septic complications and adverse outcomes, and helpful for guiding individual decisions for or against antibiotic treatment. There is need for additional educational efforts regarding the concept of "biomarker-guided antibiotic stewardship" for health care providers caring for elderly patients.

CONCLUSION

Use of biomarkers, most notably PCT, has high potential to improve the antibiotic management of elderly patients with possible infection for improving both, undertreatment and overtreatment. Within this narrative review, we aim to provide evidence-based concepts for the safe and efficient use of PCT in elderly patients.

Leveraging diagnostic stewardship within antimicrobial stewardship programmes

Novel diagnostic stewardship in infectious disease consists of interventions that modify ordering, processing, and reporting of diagnostic tests to provide the right test for the right patient, prompting the right action. The interventions work upstream and synergistically with traditional antimicrobial stewardship efforts. As diagnostic stewardship continues to gain public attention, it is critical that antimicrobial stewardship programmes not only learn how to effectively leverage diagnostic testing to improve antimicrobial use but also ensure that they are stakeholders and leaders in developing new diagnostic stewardship interventions within their institutions. This review will discuss the need for diagnostic and antimicrobial stewardship, the interplay of diagnostic and antimicrobial stewardship, evidence of benefit to antimicrobial stewardship programmes, and considerations for successfully engaging in diagnostic stewardship interventions. This article is part of the Antibiotic stewardship Special Issue: https://www.drugsincontext.com/special_issues/antimicrobial-stewardship-a-focus-on-the-need-for-moderation.

Impact of reduced antibiotic treatment duration on antimicrobial resistance in critically ill patients in the randomized controlled SAPS-trial

Background

In the previously reported SAPS trial (https://clinicaltrials.gov/ct2/show/NCT01139489), procalcitonin-guidance safely reduced the duration of antibiotic treatment in critically ill patients. We assessed the impact of shorter antibiotic treatment on antimicrobial resistance development in SAPS patients.

Materials and methods

Cultures were assessed for the presence of multi-drug resistant (MDR) or highly resistant organisms (HRMO) and compared between PCT-guided and control patients. Baseline isolates from 30 days before to 5 days after randomization were compared with those from 5 to 30 days post-randomization. The primary endpoint was the incidence of new MDR/HRMO positive patients.

Results

In total, 8,113 cultures with 96,515 antibiotic test results were evaluated for 439 and 482 patients randomized to the PCT and control groups, respectively. Disease severity at admission was similar for both groups. Median (IQR) durations of the first course of antibiotics were 6 days (4-10) and 7 days (5-11), respectively (p = 0.0001). Antibiotic-free days were 7 days (IQR 0-14) and 6 days (0-13; p = 0.05). Of all isolates assessed, 13% were MDR/HRMO positive and at baseline 186 (20%) patients were MDR/HMRO-positive. The incidence of new MDR/HRMO was 39 (8.9%) and 45 (9.3%) in PCT and control patients, respectively (p = 0.82). The time courses for MDR/HRMO development were also similar for both groups (p = 0.33).

Conclusions

In the 921 randomized patients studied, the small but statistically significant reduction in antibiotic treatment in the PCT-group did not translate into a detectable change in antimicrobial resistance. Studies with larger differences in antibiotic treatment duration, larger study populations or populations with higher MDR/HRMO incidences might detect such differences.

Machine learning and synthetic outcome estimation for individualised antimicrobial cessation

The decision on when it is appropriate to stop antimicrobial treatment in an individual patient is complex and under-researched. Ceasing too early can drive treatment failure, while excessive treatment risks adverse events. Under- and over-treatment can promote the development of antimicrobial resistance (AMR). We extracted routinely collected electronic health record data from the MIMIC-IV database for 18,988 patients (22,845 unique stays) who received intravenous antibiotic treatment during an intensive care unit (ICU) admission. A model was developed that utilises a recurrent neural network autoencoder and a synthetic control-based approach to estimate patients' ICU length of stay (LOS) and mortality outcomes for any given day, under the alternative scenarios of if they were to stop vs. continue antibiotic treatment. Control days where our model should reproduce labels demonstrated minimal difference for both stopping and continuing scenarios indicating estimations are reliable (LOS results of 0.24 and 0.42 days mean delta, 1.93 and 3.76 root mean squared error, respectively). Meanwhile, impact days where we assess the potential effect of the unobserved scenario showed that stopping antibiotic therapy earlier had a statistically significant shorter LOS (mean reduction 2.71 days, p -value <0.01). No impact on mortality was observed. In summary, we have developed a model to reliably estimate patient outcomes under the contrasting scenarios of stopping or continuing antibiotic treatment. Retrospective results are in line with previous clinical studies that demonstrate shorter antibiotic treatment durations are often non-inferior. With additional development into a clinical decision support system, this could be used to support individualised antimicrobial cessation decision-making, reduce the excessive use of antibiotics, and address the problem of AMR.

Adherence of Spanish pediatricians to "do not do" guidelines to avoid low-value care in pediatrics

The main objective of this study was to analyze the degree of knowledge and compliance of Spanish pediatricians with the "do not do" recommendations of the Spanish Association of Pediatrics. A nationwide cross-sectional, descriptive study was carried out using a 25-item questionnaire among Spanish pediatricians. Univariate, bivariate, and multivariate analyses were performed. A total of 1137 pediatricians participated in the study. Most of them were women (75.1%), older than 55 (28.3%), worked in specialized care (56.9%), with public financing (91.2%), and had been working for more than 20 years (44.9%). The median of inappropriate answers per question was 9.1%. The bivariate and multivariate analyses showed that the factors that influenced higher adequacy to the "do not do" recommendations were younger than 45 years, working in specialized care, and working in the public health system.

CONCLUSION

This research is the first nationwide study in Spain to analyze the adequacy of "do not do" pediatric clinical recommendations. The study showed a high level of compliance by Spanish pediatricians with these recommendations. However, there is a lack of knowledge in less frequent infectious pathologies such as HIV or fungal infections, in not prolonging antibiotic treatment unnecessarily and directing it appropriately according to the antibiogram results. These aspects may be improved by designing measures to enhance pediatricians' knowledge in these specific aspects. Some demographical factors are related to higher adequacy. Performing this research in other countries may allow assessing the current clinical practice of pediatricians.

WHAT IS KNOWN

• Low-value care is defined as care that delivers little or no benefit, may cause patients harm, or outcomes marginal benefits at a disproportionately increased cost. • Few nationwide studies have assessed adherence to "do not do" guidelines, especially in pediatric settings.

WHAT IS NEW

• Albeit there is a high level of compliance by Spanish pediatricians with the «do not do» recommendations, there is a lack of knowledge in different aspects that may be improved. • Some demographical factors are related to higher adequacy. Performing this research in other countries may allow assessing the current clinical practice of pediatricians.

Guidance Value of Procalcitonin Detection in Selecting Switching Points for Sequential Therapy in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease Complicated by Respiratory Failure

Objective

To analyse the guiding value of procalcitonin (PCT) for the selection of ventilation switching points in sequential mechanical ventilation for patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) and respiratory failure, and to provide a reference for the optimisation of mechanical ventilation for patients with COPD and respiratory failure.

Methods

The study included 160 patients with an acute exacerbation of COPD complicated by respiratory failure who received sequential mechanical ventilation treatment. They were divided into two groups of 80 participants. The critical point of the pulmonary infection observation window (PIC) was used as the switching point for sequential mechanical ventilation treatment in the control group, and PCT clinical node was used as the switching point for sequential mechanical ventilation treatment in the observation group. The invasive ventilation time, non-invasive mechanical ventilation time, total mechanical ventilation time, intensive care unit (ICU) treatment time, complication rate and prognosis were compared for the two groups.

Results

(1) There was no significant difference in the respiratory rate, heart rate, arterial systolic pressure, arterial oxygen partial pressure, arterial carbon dioxide partial pressure or pH value between the two groups after 1 day of treatment, and (2) invasive mechanical ventilation time, non-invasive mechanical ventilation time, total mechanical ventilation time, ICU treatment time and the incidence of complications were significantly different in the two groups (P = 0.0001).

Conclusion

Detecting PCT can guide the selection of ventilation switching points in sequential mechanical ventilation therapy for patients with COPD with respiratory failure in the acute exacerbation stage, effectively reduce the misevaluation of PIC switching points so that patients can obtain stable criteria for judgement and effectively improve the efficiency and safety of mechanical ventilation treatment for patients in the acute exacerbation stage.

Biomarkers as point-of-care tests to guide prescription of antibiotics in people with acute respiratory infections in primary care

BACKGROUND

Acute respiratory infections (ARIs) are by far the most common reason for prescribing an antibiotic in primary care, even though the majority of ARIs are of viral or non-severe bacterial aetiology. It follows that in many cases antibiotic use will not be beneficial to a patient's recovery but may expose them to potential side effects. Furthermore, limiting unnecessary antibiotic use is a key factor in controlling antibiotic resistance. One strategy to reduce antibiotic use in primary care is point-of-care biomarkers. A point-of-care biomarker (test) of inflammation identifies part of the acute phase response to tissue injury regardless of the aetiology (infection, trauma, or inflammation) and may be used as a surrogate marker of infection, potentially assisting the physician in the clinical decision whether to use an antibiotic to treat ARIs. Biomarkers may guide antibiotic prescription by ruling out a serious bacterial infection and help identify patients in whom no benefit from antibiotic treatment can be anticipated. This is an update of a Cochrane Review first published in 2014.

OBJECTIVES

To assess the benefits and harms of point-of-care biomarker tests of inflammation to guide antibiotic treatment in people presenting with symptoms of acute respiratory infections in primary care settings regardless of patient age.

SEARCH METHODS

We searched CENTRAL (2022, Issue 6), MEDLINE (1946 to 14 June 2022), Embase (1974 to 14 June 2022), CINAHL (1981 to 14 June 2022), Web of Science (1955 to 14 June 2022), and LILACS (1982 to 14 June 2022). We also searched three trial registries (10 December 2021) for completed and ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in primary care patients with ARIs that compared the use of point-of-care biomarkers with standard care. We included trials that randomised individual participants, as well as trials that randomised clusters of patients (cluster-RCTs).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data on the following primary outcomes: number of participants given an antibiotic prescription at index consultation and within 28 days follow-up; participant recovery within seven days follow-up; and total mortality within 28 days follow-up. We assessed risk of bias using the Cochrane risk of bias tool and the certainty of the evidence using GRADE. We used random-effects meta-analyses when feasible. We further analysed results with considerable heterogeneity in prespecified subgroups of individual and cluster-RCTs.

MAIN RESULTS

We included seven new trials in this update, for a total of 13 included trials. Twelve trials (10,218 participants in total, 2335 of which were children) evaluated a C-reactive protein point-of-care test, and one trial (317 adult participants) evaluated a procalcitonin point-of-care test. The studies were conducted in Europe, Russia, and Asia. Overall, the included trials had a low or unclear risk of bias. However all studies were open-labelled, thereby introducing high risk of bias due to lack of blinding. The use of C-reactive protein point-of-care tests to guide antibiotic prescription likely reduces the number of participants given an antibiotic prescription, from 516 prescriptions of antibiotics per 1000 participants in the control group to 397 prescriptions of antibiotics per 1000 participants in the intervention group (risk ratio (RR) 0.77, 95% confidence interval (CI) 0.69 to 0.86; 12 trials, 10,218 participants; I² = 79%; moderate-certainty evidence).  Overall, use of C-reactive protein tests also reduce the number of participants given an antibiotic prescription within 28 days follow-up (664 prescriptions of antibiotics per 1000 participants in the control group versus 538 prescriptions of antibiotics per 1000 participants in the intervention group) (RR 0.81, 95% CI 0.76 to 0.86; 7 trials, 5091 participants; I² = 29; high-certainty evidence). The prescription of antibiotics as guided by C-reactive protein tests likely does not reduce the number of participants recovered, within seven or 28 days follow-up (567 participants recovered within seven days follow-up per 1000 participants in the control group versus 584 participants recovered within seven days follow-up per 1000 participants in the intervention group) (recovery within seven days follow-up: RR 1.03, 95% CI 0.96 to 1.12; I² = 0%; moderate-certainty evidence) (recovery within 28 days follow-up: RR 1.02, 95% CI 0.79 to 1.32; I² = 0%; moderate-certainty evidence). The use of C-reactive protein tests may not increase total mortality within 28 days follow-up, from 1 death per 1000 participants in the control group to 0 deaths per 1000 participants in the intervention group (RR 0.53, 95% CI 0.10 to 2.92; I² = 0%; low-certainty evidence). We are uncertain as to whether procalcitonin affects any of the primary or secondary outcomes because there were few participants, thereby limiting the certainty of evidence. We assessed the certainty of the evidence as moderate to high according to GRADE for the primary outcomes for C-reactive protein test, except for mortality, as there were very few deaths, thereby limiting the certainty of the evidence.

AUTHORS' CONCLUSIONS

The use of C-reactive protein point-of-care tests as an adjunct to standard care likely reduces the number of participants given an antibiotic prescription in primary care patients who present with symptoms of acute respiratory infection. The use of C-reactive protein point-of-care tests likely does not affect recovery rates. It is unlikely that further research will substantially change our conclusion regarding the reduction in number of participants given an antibiotic prescription, although the size of the estimated effect may change.  The use of C-reactive protein point-of-care tests may not increase mortality within 28 days follow-up, but there were very few events. Studies that recorded deaths and hospital admissions were performed in children from low- and middle-income countries and older adults with comorbidities.  Future studies should focus on children, immunocompromised individuals, and people aged 80 years and above with comorbidities. More studies evaluating procalcitonin and potential new biomarkers as point-of-care tests used in primary care to guide antibiotic prescription are needed.  Furthermore, studies are needed to validate C-reactive protein decision algorithms, with a specific focus on potential age group differences.

Guidelines for the Use of Procalcitonin for Rational Use of Antibiotics

How to cite this article: Khilnani GC, Tiwari P, Zirpe KG, Chaudhary D, Govil D, Dixit S, et al. Guidelines for the Use of Procalcitonin for Rational Use of Antibiotics. Indian J Crit Care Med 2022;26(S2):S77-S94.

Early antibiotic therapy is associated with a lower probability of successful liberation from mechanical ventilation in patients with severe acute exacerbation of chronic obstructive pulmonary disease

Background

While antibiotic therapy is advocated to improve outcomes in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) whenever mechanical ventilation is required, the evidence relies on small studies carried out before the era of widespread antibiotic resistance. Furthermore, the impact of systematic antibiotic therapy on successful weaning from mechanical ventilation was never investigated accounting for the competitive risk of death. The aim of the study was to assess whether early antibiotic therapy (eABT) increases successful mechanical ventilation weaning probability as compared to no eABT, in patients with AECOPD without pneumoniae, using multivariate competitive risk regression.

Methods

Retrospective analysis of patients admitted in 2 intensive care units (ICU) from 2012 to 2020 for AECOPD without pneumonia and requiring mechanical ventilation. eABT was defined as any anti-bacterial chemotherapy introduced during the first 24 h after ICU admission. The primary outcomes were the adjusted subdistribution hazard ratio (SHR) of the probability of being successfully weaned from mechanical ventilation (i.e. non-invasive and invasive ventilation) according to eABT status and accounting for the competitive risk of death.

Results

Three hundred and ninety-one patients were included, of whom 66% received eABT. eABT was associated with a lower probability of successful liberation from mechanical ventilation when accounting for the competing risk of death in multivariate analyses (SHR 0.71 [95% confidence interval, 0.57–0.89], p < 0.01), after adjustment with covariates of disease severity. This association was present in all subgroups except in patients under invasive mechanical ventilation on ICU day-1, in patients with ICU day-1 worst PaCO₂ > 74 torr (median value) and in patients with a documented bacterial bronchitis at ICU admission. Ventilator-free days at day 28, ICU-free days at day 28 and invasive mechanical ventilation-free days at day 28, were significantly lower in the eABT group, while there was no significant difference in mortality at day 28 between patients who received eABT and those who did not.

Conclusions

eABT was independently associated with a lower probability of being successfully weaned from mechanical ventilation, suggesting that the clinician decision to overrule systematic administration of eABT was not associated with a detectable harm in AECOPD ICU patients without pneumonia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01060-2.

Procalcitonin-guided antibiotic therapy for pediatrics with infective disease: A updated meta-analyses and trial sequential analysis

Objective

We aimed to evaluate the effect of procalcitonin (PCT) guided therapy on antibiotic exposure in pediatric patients with infectious disease.

Methods

We performed an updated systematic review and meta-analysis of randomized controlled trials (RCTs) identified in systematic searches of MEDLINE, Embase, the Cochrane Database, Google Scholar, and SinoMed (through July 2021). The primary outcome was the length of the antibiotic therapy. Required information size (RIS) was calculated using trial sequential analysis (TSA).

Results

Four RCTs with 1,313 patients with infectious disease were included. Overall, after a mean 22-day follow-up, PCT-guided antibiotic therapy was associated with a significantly shorter length of antibiotic therapy compared with the control group (WMD, −2.22 days; 95% CI, −3.41 to −1.03; P <0.001) and a decreased rate of antibiotic adverse events (RR, 0.25; 95% CI, 0.11–0.58; P <0.001). However, the length of hospital stay (WMD, −0.39 days; 95% CI, −0.84 to 0.07; P = 0.094), rates of antibiotic prescription (RR, 1.10; 95% CI, 0.97–1.25; P = 0.122), hospital readmission (RR, 1.03; 95% CI, 0.92–1.16; P = 0.613) and mortality (RR, 0.73; 95% CI, 0.17–3.19; P = 0.674) were comparable between the PCT-guided antibiotic and control groups. TSA showed that the RIS was 2,340, indicating a statistically significantly shorter length of antibiotic therapy between PCT-guided antibiotic and control groups (P <0.05).

Conclusions

PCT-guided management seems to be able to decrease antibiotic exposure in patients with infectious disease. However, much larger prospective clinical studies are warranted to confirm these findings.

The Etiology of Community-Acquired Pneumonia Correlates with Serum Inflammatory Markers in Children

Community-acquired pneumonia (CAP) severely affects pediatric hospitalizations. This study assessed the contribution of CAP to hospitalizations, its etiology in relationship with age, and the inflammatory markers. Between 2013 and 2018, 1064 CAP patients were hospitalized and diagnosed with bacterial/possibly bacterial pneumonia (BP), viral/possibly viral pneumonia (VP) and atypical pneumonia (AP). The etiology was confirmed using blood/pleural fluid culture/polymerase chain reaction (PCR), rapid antigen test/PCR in nasopharyngeal swabs, or serological studies. CAP accounted for 9.9% of hospitalizations and 14.8% of patient days. BP was diagnosed in 825 (77.5%), VP in 190 (17.9%), and AP in 49 (4.6%) cases; the confirmed etiology (n = 209; 20%) included mostly influenza (39%; n = 82), respiratory syncytial virus (RSV, 35%; n = 72), and Mycoplasma pneumoniae (19%; n = 39). VP frequency decreased with age (41% in < 3 mo to 9% in ≥ 60 mo), in contrast to AP (13% in ≥ 60 mo). Among the analyzed parameters, the best differentiating potential was shown by: C-reactive protein (CRP, AUCBP-VP = 0.675; 95% CI: 0.634−0.715), procalcitonin (AUCBP-AP = 0.73; 95% CI: 0.67−0.794), and CRP/procalcitonin (AUCAP-VP = 0.752; 95% CI: 0.67−0.83); a good positive predictive value (88.8%, 98.3%, and 91.6%, respectively) but a low negative predictive value (29.5%, 13.1%, and 40.7%, respectively) was observed. CAP influences hospital patient days more than the crude number of patients would suggest. On a clinical basis, BP is mainly recognized, although viral pneumonia is confirmed most often. RSV and influenza are responsible for a huge percentage of hospitalized cases, as well as M. pneumoniae in children aged ≥ 5 years. Serum inflammatory markers may help differentiate etiological factors.

Markedly elevated procalcitonin due to anaphylactic shock, a case report

Procalcitonin (PCT) is a well-known biomarker that is directly connected to bacterial infection especially when it reaches significantly high levels. It is extremely rare to be witnessed in non-bacterial infections such as viral or parasitic. It may be elevated in other conditions such as trauma and autoimmune diseases. We present a rare case of a young gentleman, who had an extremely high PCT level that appeared to be a result of anaphylaxis due to worm infestation.

Diagnostic Accuracy of Procalcitonin upon Emergency Department Admission during SARS-CoV-2 Pandemic

Highlights

Abstract

Introduction: Procalcitonin is a marker for bacterial diseases and has been used to guide antibiotic prescription. Procalcitonin accuracy, measured at admission, in patients with community-acquired pneumonia (CAP), is unknown in the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Objectives: To evaluate the diagnostic accuracy of procalcitonin to assess the need for antibiotic treatment in patients with CAP presenting to the emergency department during the SARS-CoV-2 pandemic. Methods: We performed a real-world diagnostic retrospective accuracy study of procalcitonin in patients admitted to the emergency department. Measures of diagnostic accuracy were calculated based on procalcitonin results compared to the reference standard of combined microbiological and radiological analysis. Sensitivity, specificity, positive and negative predictive values, and area under (AUC) the receiver-operating characteristic (ROC) curve were calculated in two analyses: first assessing procalcitonin ability to differentiate microbiologically proven bacteria from viral CAP and then clinically diagnosed bacterial CAP from viral CAP. Results: When using a procalcitonin threshold of 0.5 ng/mL to identify bacterial etiology within patients with CAP, we observed sensitivity and specificity of 50% and 64.1%, and 43% and 82.6%, respectively, in the two analyses. The positive and negative predictive values of a procalcitonin threshold of 0.5 ng/mL to identify patients for whom antibiotics should be advised were 46.4% and 79.7%, and 48.9% and 79% in the two analyses, respectively. The AUC for the two analyses was 0.60 (95% confidence interval [CI] 0.52–0.68) and 0.62 (95% CI, 0.55–0.69). Conclusions: Procalcitonin measured upon admission during the SARS-CoV-2 pandemic should not guide antibiotic treatment in patients with CAP.

[Acute and chronic cough - differential diagnosis and treatment]

Cough is a frequent reason for consultation in the general practitioner's office. Most of the time, the symptom is harmless and self-limiting, as in the case of a banal cold cough, for example - however, serious diseases such as malignancies can also be the cause. Evaluation is therefore not always easy. This article presents a targeted and appropriate approach and discusses which treatments are recommended and effective.Acute and chronic cough are differentiated according to the duration of symptoms (up to 8 weeks/longer than 8 weeks). The most common cause of acute cough is a self-limiting viral infection of the upper respiratory tract; the most important differential diagnosis is community-acquired pneumonia. If there are no defined warning signs (red flags), the history and clinical examination are sufficient to establish the diagnosis in the case of an acute cough; medication is not necessary. In the case of a chronic cough, a chest X-ray is usually ordered and then further investigations are carried out in accordance with the most probable suspected diagnosis; probationary therapies are an important part of the workup. Coughs that are refractory to treatment or unexplained require individualised treatment (pharmacological, including off-label, non-pharmacological) and regular re-evaluation.

Stemming the Rise of Antibiotic Use for Community-Acquired Acute Respiratory Infections during COVID-19 Pandemic

At the start of the COVID-19 pandemic, there was an increase in the use of antibiotics for the treatment of community-acquired respiratory tract infection (CA-ARI) in patients admitted for suspected or confirmed COVID-19, raising concerns for misuse. These antibiotics are not under the usual purview of the antimicrobial stewardship unit (ASU). Serum procalcitonin, a biomarker to distinguish viral from bacterial infections, can be used to guide antibiotic recommendations in suspected lower respiratory tract infection. We modified our stewardship approach, and used a procalcitonin-guided strategy to identify “high yield” interventions for audits in patients admitted with CA-ARI. With this approach, there was an increase in the proportion of patients with antibiotics discontinued within 4 days (16.5% vs. 34.9%, p < 0.001), and the overall duration of antibiotic therapy was significantly shorter [7 (6−8) vs. 6 (3−8) days, p < 0.001]. There was a significant decrease in patients with intravenous-to-oral switch of antibiotics to “complete the course” (45.3% vs. 34.4%, p < 0.05). Of the patients who had antibiotics discontinued, none were restarted on antibiotics within 48 h, and there was no-30-day readmission or 30-day mortality attributed to respiratory infection. This study illustrates the importance of the antimicrobial stewardship during the pandemic and the need for ASU to remain attuned to prescriber’s practices, and adapt accordingly to address antibiotic misuse to curb antimicrobial resistance.

Pham S, P.M. Vo T, X. Duong C, A. Perwitasari D, H.K. Truong N, T.H. Quach D, N.P. Nguyen T, T.T. Duong V, M. Nguyen P, H. Nguyen T, Taxis K, Nguyen T. Pneumonia: Drug-Related Problems and Hospital Readmissions

Pneumonia is one of the most common infectious diseases and the fourth leading cause of death globally. According to US statistics in 2019, pneumonia is the most common cause of sepsis and septic shock. In the US, inpatient pneumonia hospitalizations account for the top 10 highest medical costs, totaling $9.5 billion for 960,000 hospital stays. The emergence of antibiotic resistance in the treatment of infectious diseases, including the treatment of pneumonia, is a globally alarming problem. Antibiotic resistance increases the risk of death and re-hospitalization, prolongs hospital stays, and increases treatment costs, and is one of the greatest threats in modern medicine. Drug-related problems (DRPs) in pneumonia - such as suboptimal antibiotic indications, prolonged treatment duration, and drug interactions - increase the rate of antibiotic resistance and adverse effects, thereby leading to an increased burden in treatment. In a context in which novel and effective antibiotics are scarce, mitigating DRPs in order to reduce antibiotic resistance is currently a prime concern. A variety of interventions proven useful in reducing DRPs are antibiotic stewardship programs, the use of biomarkers, computerized physician order entries and clinical decision support systems, and community-acquired pneumonia scores.

Role of procalcitonin in diagnosis of community acquired pneumonia in Children

Background

The role of serum Procalcitonin (PCT) in adults in diagnosis of Community acquired pneumonia (CAP) is well established, however, role in pediatric CAP remains controversial.

Objectives

The objective of this study was to investigate the utility of serum procalcitonin in differentiating bacterial community-acquired lower respiratory tract infection from non-bacterial respiratory infection in children; radiologically confirmed pneumonia was used as the reference. In addition, we assessed the utility of adding the PCT assay to the clinical criteria for diagnosis of pneumonia.

Study design

Subanalysis of a larger prospective,multicentriccohort study.

Participants

Children, 2 months to 59 months of age, attending paediatric OPD of 5 urban tertiary care hospitals, suffering from acute respiratory infection (ARI).

Intervention

Detailed clinical history and examination findings of enrolled children were recorded on predesigned case record form. Samples for PCT were obtained at admission and were measured centrally at the end of the study except for one site using VIDAS® B.R.A.H.M.S PCT kit (Biomerieux SA, France).

Outcomes

Sensitivity and specificity of procalcitonin for diagnosis of radiologically confirmed pneumonia.

Results

Serum Procalcitonin was measured in 370 patients; median (IQR) age of these children being 12 (7, 22) months, 235 (63.5%) were boys. The median (IQR) serum procalcitonin concentration was 0.1(0.05, 0.4) ng/mL.Sensitivity and specificity of raised PCT (> 0.5 ng/mL) for pneumonia as per any CXR abnormalities were 29.7% and87.5%,(P < 0.001) respectively. Raised PCT was also significantly associated with consolidation (34.5%,79.2%,P < 0.02)and pleural effusion(54.6%,79%,P < 001). Adding PCT to the existing clinical criteria of WHO did not improve the sensitivity for diagnosis of pneumonia. PCT was significantly higher in children with severe pneumonia.

Conclusion

Positive PCT (> 0.5 ng/mL) is significantly associated with radiographic pneumonia but not with pneumonia based on WHO criteria.However, it can act as a surrogate marker for severe pneumonia.

In-Hospital Macro-, Meso-, and Micro-Drivers and Interventions for Antibiotic Use and Resistance: A Rapid Evidence Synthesis of Data from Canada and Other OECD Countries

Hospitals continue to face challenges in reducing incorrect antibiotic use due to social and cultural factors at the level of the health system, the care facility, the provider, and the patient. The objective of this paper is to highlight the social and cultural drivers of antimicrobial use and resistance and targeted interventions for secondary and tertiary care settings in Canada and other OECD countries. This paper is an extension of the synthesis conducted for the Public Health Agency of Canada's 2019 Spotlight Report: Preserving Antibiotics Now and Into the Future. We conducted a systematic review with a few modifications to meet rapid timelines. We conducted a search in Ovid MEDLINE and McMaster University's evidence databases for systematic reviews and then for individual Canadian studies. To cast a wider net, we searched OECD organization websites and screened reference lists from systematic reviews. We synthesized the evidence narratively and categorized the evidence into macro-, meso-, and microlevel. A total of 70 studies were (a) from OCED countries and summarized evidence of potential sociocultural antimicrobial resistance and use barriers or facilitators and/or interventions addressing these challenges; (b) systematic reviews with 50% of included studies that are situated in secondary and tertiary settings; and (c) published in Canada's two official languages, English and French. We found that hospital structures and policies may influence antibiotic utilization and variations in antimicrobial management. Microlevel factors may sway inappropriate prescribing among clinicians. The amount and type of antibiotics used may affect resistance rates. Interventions were mainly comprised of antibiotic stewardship and training that modify clinician behavior and that educate patients and carers. This evidence synthesis illustrates the various drivers of, and interventions for, antimicrobial use and resistance at the macro-, meso-, and microlevel in secondary and tertiary settings. We demonstrate that upstream drivers may lead to downstream events that influence antimicrobial resistance.

Candidate High-Resolution Mass Spectrometry-Based Reference Method for the Quantification of Procalcitonin in Human Serum Using a Characterized Recombinant Protein as a Primary Calibrator

Procalcitonin (PCT) is a widely used biomarker for rapid sepsis diagnosis and antibiotic stewardship. Variability of results in commercial assays has highlighted the need for standardization of PCT measurements. An antibody-free candidate reference measurement procedure (RMP) based on the isotope dilution mass spectrometry and protein calibration approach was developed and validated to quantify PCT in human serum. The method allows quantification of PCT from 0.25 to 13.74 μg/L (R > 0.998) with extension up to 132 μg/L after dilution of samples with PCT concentration above 13.74 μg/L. Intraday bias was between −3.3 and +5.7%, and interday bias was between −3.0 and −0.7%. Intraday precision was below 5.1%, and interday precision was below 4.0%. The candidate RMP was successfully applied to the absolute quantification of PCT in five frozen human serum pools. A recombinant PCT used as a primary calibrator was characterized by high-resolution mass spectrometry and amino acid analysis to establish traceability of the results to the SI units. This candidate RMP is fit to assign target values to secondary certified reference materials (CRMs) for further use in external quality assessment schemes to monitor the accuracy and comparability of the commercially available immunoassay results and to confirm the need for improving the harmonization of PCT assays. The candidate RMP will also be used to evaluate whether the correlation between the candidate RMP and immunoassays is sufficiently high. Overall, this candidate RMP will support reliable sepsis diagnosis and guide treatment decisions, patient monitoring, and outcomes.

Potential impact of national recommendations to use short course antibiotic therapy on antibiotic use in the emergency department of a UK hospital: retrospective observational study

BACKGROUND AND IMPORTANCE

The National Institute for Health and Care Excellence (NICE) antimicrobial prescribing guidelines for common infections recommend short course antimicrobial therapy in order to reduce antibiotic associated harm.

OBJECTIVE

To quantify the opportunity to reduce antibiotic use in an emergency department (ED) through adoption of these short antibiotic course recommendations.

DESIGN, SETTINGS AND PARTICIPANTS

A retrospective observational study in an ED in the UK with 95 000 attendances a year. Patients managed in the ED between 1 December and 31 December 2019 with the following infections were identified: acute otitis media, human and animal bites, pyelonephritis, lower urinary tract infections, cellulitis, cough, infective exacerbation of chronic obstructive pulmonary disease, pneumonia, sore throat, sinusitis, and diverticulitis.

OUTCOME MEASURE

Excess antibiotic use due to either a protracted course length, or not meeting criteria for antibiotics.

RESULTS

395 patients (260 adults and 135 children) were identified. Of the 1215 days of antibiotic therapy, 198 (16%) were excess because of protracted course lengths. In terms of antibiotic defined daily doses (DDD), there were 1201.5 antibiotic DDD prescribed, of which 232 (19%) DDD were excess because of protracted course lengths. If both protracted courses and unnecessary antibiotic use were included, then 321 (27%) DDD were excess. Excess antibiotic use and total antibiotic use by infection group were: 123/546 (23%) DDD in lower respiratory tract infection, 46/59 (79%) in upper respiratory tract infection, 44/231 (19%) in upper and lower urinary tract infection, 0/113 (0%) cellulitis, 77/180 (43%) bites, and 30/40 (75%) diverticulitis. Excess antibiotic use, as a proportion of all antibiotic use in the ED, was 321/4291 (7.5%) DDD, and of whole hospital antibiotic use, the ED's excess use was 321/33 566 (0.96%).

CONCLUSION

Adoption of NICE antibiotic prescribing guidelines for common infections has the potential to reduce total antibiotic use in the ED by 7.5% and contribute to the hospital-wide antibiotic stewardship programme.

Early procalcitonin to predict mortality in critically ill COVID-19 patients: a multicentric cohort study

BACKGROUND

High levels of procalcitonin (PCT) have been associated with a higher risk of mortality in COVID-19 patients. We explored the prognostic role of early PCT assessment in critically ill COVID-19 patients and whether PCT predictive performance would be influenced by immunosuppression.

METHODS

Retrospective multicentric analysis of prospective collected data in COVID-19 patients consecutively admitted to 36 intensive care units (ICUs) in Spain and Andorra from March to June 2020. Adult (>18 years) patients with confirmed COVID-19 and available PCT values (<72 hours from ICU admission) were included. Patients were considered as "No Immunosuppression" (NI), "Chronic Immunosuppression" (CI) and "Acute Immunosuppression" (AIT if only tocilizumab; AIS if only steroids, AITS if both). The primary outcome was the ability of PCT to predict ICU mortality.

RESULTS

Of the 1079 eligible patients, 777 patients were included in the analysis. Mortality occurred in 227 (28%) patients. In the NI group 144 (19%) patients were included, 67 (9%) in the CI group, 66 (8%) in the AIT group, 262 (34%) in the AIS group and 238 (31%) in the AITS group; PCT was significantly higher in non-survivors when compared with survivors (0.64 [0.17-1.44] vs. 0.23 [0.11-0.60] ng/mL; p<0.01); however, in the multivariable analysis, PCT values was not independently associated with ICU mortality. PCT values and ICU mortality were significantly higher in patients in the NI and CI groups.

CONCLUSIONS

PCT values are not independent predictors of ICU mortality in COVID-19 patients. Acute immunosuppression significantly reduced PCT values, although not influencing its predictive value.

Procalcitonin for antimicrobial stewardship among cancer patients admitted with COVID-19

Background

Procalcitonin (PCT) has been used to guide antibiotic therapy in bacterial infections. We aimed to determine the role of PCT in decreasing the duration of empiric antibiotic therapy among cancer patients admitted with COVID-19.

Methods

This retrospective study included cancer patients admitted to our institution for COVID-19 between March 1, 2020, and June 28, 2021, with a PCT test done within 72 hr after admission. Patients were divided into two groups: PCT <0.25 ng/ml and PCT ≥0.25 ng/ml. We assessed pertinent cultures, antibacterial use, and duration of empiric antibacterial therapy.

Results

The study included 530 patients (median age, 62 years [range, 13-91]). All the patients had ≥1 culture test within 7 days following admission. Patients with PCT <0.25 ng/ml were less likely to have a positive culture than were those with PCT ≥0.25 ng/ml (6% [20/358] vs. 17% [30/172]; p<0.0001). PCT <0.25 ng/ml had a high negative predictive value for bacteremia and 30 day mortality. Patients with PCT <0.25 ng/ml were less likely to receive intravenous (IV) antibiotics for >72 hr than were patients with PCT ≥0.25 ng/ml (45% [162/358] vs. 69% [119/172]; p<0.0001). Among patients with PCT <0.25 ng/ml and negative cultures, 30 day mortality was similar between those who received IV antibiotics for ≥72 hr and those who received IV antibiotics for shorter durations (2% [2/111] vs. 3% [5/176], p=0.71).

Conclusions

Among cancer patients with COVID-19, PCT level <0.25 ng/ml is associated with lower likelihood of bacterial co-infection and greater likelihood of a shorter antibiotic course. In patients with PCT level <0.25 ng/ml and negative cultures, an antibiotic course of >72 hr may not be necessary. PCT could be useful in enhancing antimicrobial stewardship in cancer patients with COVID-19.

Funding

This research was supported by the National Institutes of Health/National Cancer Institute under award number P30CA016672, which supports MD Anderson Cancer Center's Clinical Trials Office.

[Which biomarkers for diagnosis and guidance of anti-infection treatment in sepsis?]

To date no biomarker has been identified bringing together perfect sensitivity and specificity to discriminate between inflammation and infections. Since the 1930s new markers of tissue damage and endothelial damage have been identified but which are incapable of identifying infections in every clinical setting to enable initiation of early antibiotic treatment. In this review the most important classical biomarkers and upcoming new PCR-based approaches are addressed. These markers are highlighted with respect to special clinical settings and to control the success of antibiotic treatment. The issue of discrimination between inflammation and infection is not yet solved. Based on one single biomarker it is impossible to decide whether infection is the reason for the patient's worsening condition but the combination of biomarkers or the integration of new biomarkers may be a meaningful supplement. The measurement of different biomarkers of infection or inflammation is part of the routine in critical care and will be essential in the future.

Rapid Diagnostic Tests to Guide Case Management of and Improve Antibiotic Stewardship for Pediatric Acute Respiratory Illnesses in Resource-Constrained Settings: a Prospective Cohort Study in Southwestern Uganda

Pediatric acute respiratory illness (ARI) is one of the most common reasons for evaluation at peripheral health centers in sub-Saharan Africa and is frequently managed based on clinical syndrome alone. Although most ARI episodes are likely caused by self-limited viral infections, the majority are treated with antibiotics. This overuse contributes to the development of antimicrobial resistance. To evaluate the preliminary feasibility and potential impact of adding pathogen-specific and clinical biomarker diagnostic testing to existing clinical management algorithms, we conducted a prospective, observational cohort study of 225 children presenting with malaria-negative, febrile ARI to the outpatient department of a semi-urban peripheral health facility in southwestern Uganda from October 2019 to January 2020. In addition to routine clinical evaluation, we performed influenza and Streptococcus pneumoniae antigen testing and measured levels of C-reactive protein, procalcitonin, and lactate in the clinic's laboratory, and conducted a follow-up assessment by phone 7 days later. Almost one-fifth of participants (40/225) tested positive for influenza. Clinical biomarker measurements were low with C-reactive protein of >40 mg/L in only 11% (13/222) of participants and procalcitonin >0.25 ng/mL in only 13% (16/125). All but two children received antibiotic treatment; only 3% (7/225) were admitted. At follow-up, 59% (118/201) of caregivers reported at least one persistent symptom, but fever had resolved for all children. Positive influenza testing was associated with persistent symptoms. In summary, we demonstrate that simple, rapid pathogen-specific testing and biomarker measurement are possible in resource-limited settings and could improve syndromic management and, in turn, antibiotic stewardship. IMPORTANCE Globally, respiratory illness is one of the most common reasons that children seek care. It is often treated inappropriately with antibiotics, which can drive the development of antibiotic resistance. In resource-rich settings, testing for specific pathogens or measurement of clinical biomarkers, such as procalcitonin and C-reactive protein, is often employed to help determine which children should receive antibiotics. However, there are limited data on the use of these tests in resource-constrained, outpatient contexts in sub-Saharan Africa. We enrolled children with respiratory illness presenting to a clinic in southwestern Uganda and performed testing for influenza, Streptococcus pneumoniae, C-reactive protein, and procalcitonin on-site. Almost all children received antibiotics. We demonstrate that employing clinical algorithms that include influenza and clinical biomarker testing could significantly decrease antibiotic prescriptions. Our study therefore provides preliminary data to support the feasibility and potential utility of diagnostics to improve management of respiratory illness in resource-constrained settings.

A comparison of host response strategies to distinguish bacterial and viral infection

OBJECTIVES

Compare three host response strategies to distinguish bacterial and viral etiologies of acute respiratory illness (ARI).

METHODS

In this observational cohort study, procalcitonin, a 3-protein panel (CRP, IP-10, TRAIL), and a host gene expression mRNA panel were measured in 286 subjects with ARI from four emergency departments. Multinomial logistic regression and leave-one-out cross validation were used to evaluate the protein and mRNA tests.

RESULTS

The mRNA panel performed better than alternative strategies to identify bacterial infection: AUC 0.93 vs. 0.83 for the protein panel and 0.84 for procalcitonin (P<0.02 for each comparison). This corresponded to a sensitivity and specificity of 92% and 83% for the mRNA panel, 81% and 73% for the protein panel, and 68% and 87% for procalcitonin, respectively. A model utilizing all three strategies was the same as mRNA alone. For the diagnosis of viral infection, the AUC was 0.93 for mRNA and 0.84 for the protein panel (p<0.05). This corresponded to a sensitivity and specificity of 89% and 82% for the mRNA panel, and 85% and 62% for the protein panel, respectively.

CONCLUSIONS

A gene expression signature was the most accurate host response strategy for classifying subjects with bacterial, viral, or non-infectious ARI.

Does procalcitonin have clinical utility in the management of paediatric community-acquired pneumonia? A PRO/CON debate

Although the overwhelming majority of community-acquired pneumonia (CAP) in children is caused by viral infections, treatment of CAP is among the most common indications for antibiotic use in children. This is largely driven by the imprecision of clinical diagnostic tools to differentiate viral from bacterial pneumonia and highlights the need for improved approaches to optimizing management of CAP in children. In this issue of JAC-Antimicrobial Resistance, we present a PRO/CON debate that discusses the clinical utility of procalcitonin in children with CAP.

Procalcitonin Increase Is Associated with the Development of Critical Care-Acquired Infections in COVID-19 ARDS

Secondary bacterial infection in COVID-19 patients is associated with increased mortality and disproportionately affects critically ill patients. This single-centre retrospective observational study investigates the comparative efficacy of change in procalcitonin (PCT) and other commonly available biomarkers in revealing or predicting microbiologically proven secondary infection in critical COVID-19 patients. Adult patients admitted to an intensive care unit (ICU) with confirmed SARS-CoV-2 infection between 9 March 2020 and 5 June 2020 were recruited to the study. For daily biomarker and secondary infection, laboratory-confirmed bloodstream infection (LCBI) and ventilator-associated pneumonia/tracheobronchitis (VAP/VAT) data were collected. We observed a PCT rise in 53 (81.5%) of the patients, a C-reactive protein (CRP) rise in 55 (84.6%) and a white blood cell count (WBC) rise in 61 (93.8%). Secondary infection was confirmed in 33 (50.8%) of the patients. A PCT rise was present in 97.0% of patients with at least one confirmed VAP/VAT and/or LCBI event. CRP and WBC rises occurred in 93.9% and 97.0% of patients with confirmed VAP/VAT and/or LCBI, respectively. Logistic regression analysis found that, when including all biomarkers in the same model, there was a significant association between PCT rise and the occurrence of LCBI and/or VAP/VAT (OR = 14.86 95%CI: 2.20, 342.53; p = 0.021). Conversely, no statistically significant relationship was found between either a CRP rise (p = 0.167) or a WBC rise (p = 0.855) and the occurrence of VAP/VAT and/or LCBI. These findings provide a promising insight into the usefulness of PCT measurement in predicting the emergence of secondary bacterial infection in ICU.

Paediatric Antimicrobial Stewardship for Respiratory Infections in the Emergency Setting: A Systematic Review

Antimicrobial resistance occurs due to the propensity of microbial pathogens to develop resistance to antibiotics over time. Antimicrobial stewardship programs (ASPs) have been developed in response to this growing crisis, to limit unnecessary antibiotic prescription through initiatives such as education-based seminars, prescribing guidelines, and rapid respiratory pathogen (RRP) testing. Paediatric patients who present to the emergency setting with respiratory symptoms are a particularly high-risk population susceptible to inappropriate antibiotic prescribing behaviours and are therefore an ideal cohort for focused ASPs. The purpose of this systematic review was to assess the efficacy and safety of ASPs in this clinical context. A systematic search of PubMed, Medline, EMBASE and the Cochrane Database of Systematic Reviews was conducted to review the current evidence. Thirteen studies were included in the review and these studies assessed a range of stewardship interventions and outcome measures. Overall, ASPs reduced the rates of antibiotic prescription, increased the prescription of narrow-spectrum antibiotics, and shortened the duration of antibiotic therapy. Multimodal interventions that were education-based and those that used RRP testing were found to be the most effective. Whilst we found strong evidence that ASPs are effective in reducing antibiotic prescribing, further studies are required to assess whether they translate to equivalent clinical outcomes.

Impact of Pharmacist-Directed Simplified Procalcitonin Algorithm on Antibiotic Therapy in Critically Ill Patients With Sepsis

Purpose

The purpose was to determine whether a simplified procalcitonin (PCT) algorithm guided by pharmacist recommendations reduces antibiotic duration of therapy in critically ill patients with suspected sepsis.

Methods

This was a single-centered pre-post study conducted at a 1368-bed community teaching hospital in the United States. A prospective cohort with pharmacist intervention utilizing a simplified PCT algorithm was compared with a retrospective historical cohort with standard therapy. Adult patients admitted to the intensive care unit (ICU) with suspected sepsis who received intravenous antibiotics were included. A pharmacist recommended continuation or discontinuation of antibiotics based on the PCT level per our algorithm and full clinical assessment of the patient. Primary outcome was total duration of antibiotic therapy. Secondary outcomes were ICU and hospital length of stay (LOS), reinitiation of antibiotic therapy within 72 hours of discontinuation, and 28-day in-hospital mortality.

Results

From September 2017 to May 2018, 360 patients were screened for eligibility. Of these, 26 patients were included in the PCT group and 26 patients in the standard therapy group. Baseline characteristics were similar between groups. A significant difference in duration of antibiotic therapy was detected with a median of 9 days in the PCT group versus 12 days in the standard therapy group (P = .02). There were no significant differences in secondary endpoints of ICU and hospital LOS, reinitiation of antibiotics at 72 hours, or 28-day mortality.

Conclusion

Use of a simplified PCT algorithm with pharmacist-guided recommendations significantly reduced the duration of antibiotic therapy in critically ill patients with sepsis.

Multistep antimicrobial stewardship intervention on antibiotic prescriptions and treatment duration in children with pneumonia

INTRODUCTION

The Italian antimicrobial prescription rate is one of the highest in Europe, and antibiotic resistance has become a serious problem with high costs and severe consequences, including prolonged illnesses, the increased period of hospitalization and mortality. Inadequate antibiotic prescriptions have been frequently reported, especially for lower respiratory tract infections (LRTI); many patients receive antibiotics for viral pneumonia or bronchiolitis or broad-spectrum antibiotics for not complicated community-acquired pneumonia. For this reason, healthcare organizations need to implement strategies to raise physicians' awareness about this kind of drug and their overall effect on the population. The implementation of antibiotic stewardship programs and the use of Clinical Pathways (CPs) are excellent solutions because they have proven to be effective tools at diagnostic and therapeutic levels.

AIMS

This study evaluates the impact of CPs implementation in a Pediatric Emergency Department (PED), analyzing antibiotic prescriptions before and after the publication in 2015 and 2019. The CP developed in 2019 represents an update of the previous one with the introduction of serum procalcitonin. The study aims to evaluate the antibiotic prescriptions in patients with community-acquired pneumonia (CAP) before and after both CPs (2015 and 2019).

METHODS

The periods analyzed are seven semesters (one before CP-2015 called PRE period, five post CP-2015 called POST 1-5 and 1 post CP-2019 called POST6). The patients have been split into two groups: (i) children admitted to the Pediatric Acute Care Unit (INPATIENTS), and (ii) patients evaluated in the PED and sent back home (OUTPATIENTS). We have analyzed all descriptive diagnosis of CAP (the assessment of episodes with a descriptive diagnosis were conducted independently by two pediatricians) and CAP with ICD9 classification. All antibiotic prescriptions for pediatric patients with CAP were analyzed.

RESULTS

A drastic reduction of broad-spectrum antibiotics prescription for inpatients has been noticed; from 100.0% in the PRE-period to 66.7% in POST1, and up to 38.5% in POST6. Simultaneously, an increase in amoxicillin use from 33.3% in the PRE-period to 76.1% in POST1 (p-value 0.078 and 0.018) has been seen. The outpatients' group's broad-spectrum antibiotics prescriptions decreased from 54.6% PRE to 17.4% in POST6. Both for outpatients and inpatients, there was a decrease of macrolides. The inpatient group's antibiotic therapy duration decreased from 13.5 days (PRE-period) to 7.0 days in the POST6. Antibiotic therapy duration in the outpatient group decreased from 9.0 days (PRE) to 7.0 days (POST1), maintaining the same value in subsequent periods. Overlapping results were seen in the ICD9 group for both inpatients and outpatients.

CONCLUSIONS

This study shows that CPs are effective tools for an antibiotic stewardship program. Indeed, broad-spectrum antibiotics usage has dropped and amoxicillin prescriptions have increased after implementing the CAP CP-2015 and the 2019 update.

All-cause mortality and disease progression in SARS-CoV-2-infected patients with or without antibiotic therapy: an analysis of the LEOSS cohort

Purpose

Reported antibiotic use in coronavirus disease 2019 (COVID-19) is far higher than the actual rate of reported bacterial co- and superinfection. A better understanding of antibiotic therapy in COVID-19 is necessary.

Methods

6457 SARS-CoV-2-infected cases, documented from March 18, 2020, until February 16, 2021, in the LEOSS cohort were analyzed. As primary endpoint, the correlation between any antibiotic treatment and all-cause mortality/progression to the next more advanced phase of disease was calculated for adult patients in the complicated phase of disease and procalcitonin (PCT) ≤ 0.5 ng/ml. The analysis took the confounders gender, age, and comorbidities into account.

Results

Three thousand, six hundred twenty-seven cases matched all inclusion criteria for analyses. For the primary endpoint, antibiotic treatment was not correlated with lower all-cause mortality or progression to the next more advanced (critical) phase (n = 996) (both p > 0.05). For the secondary endpoints, patients in the uncomplicated phase (n = 1195), regardless of PCT level, had no lower all-cause mortality and did not progress less to the next more advanced (complicated) phase when treated with antibiotics (p > 0.05). Patients in the complicated phase with PCT > 0.5 ng/ml and antibiotic treatment (n = 286) had a significantly increased all-cause mortality (p = 0.029) but no significantly different probability of progression to the critical phase (p > 0.05).

Conclusion

In this cohort, antibiotics in SARS-CoV-2-infected patients were not associated with positive effects on all-cause mortality or disease progression. Additional studies are needed. Advice of local antibiotic stewardship- (ABS-) teams and local educational campaigns should be sought to improve rational antibiotic use in COVID-19 patients.

Effect of C reactive protein point-of-care testing on antibiotic prescribing for lower respiratory tract infections in nursing home residents: cluster randomised controlled trial

OBJECTIVE

To evaluate whether C reactive protein point-of-care testing (CRP POCT) safely reduces antibiotic prescribing for lower respiratory tract infections in nursing home residents.

DESIGN

Pragmatic, cluster randomised controlled trial.

SETTING

The UPCARE study included 11 nursing home organisations in the Netherlands.

PARTICIPANTS

84 physicians from 11 nursing home organisations included 241 participants with suspected lower respiratory tract infections from September 2018 to the end of March 2020.

INTERVENTIONS

Nursing homes allocated to the intervention group had access to CRP POCT. The control group provided usual care without CRP POCT for patients with suspected lower respiratory tract infections.

MAIN OUTCOME MEASURES

The primary outcome measure was antibiotic prescribing at initial consultation. Secondary outcome measures were full recovery at three weeks, changes in antibiotic management and additional diagnostics during follow-up at one week and three weeks, and hospital admission and all cause mortality at any point (initial consultation, one week, or three weeks).

RESULTS

Antibiotics were prescribed at initial consultation for 84 (53.5%) patients in the intervention group and 65 (82.3%) in the control group. Patients in the intervention group had 4.93 higher odds (95% confidence interval 1.91 to 12.73) of not being prescribed antibiotics at initial consultation compared with the control group, irrespective of treating physician and baseline characteristics. The between group difference in antibiotic prescribing at any point from initial consultation to follow-up was 23.6%. Differences in secondary outcomes between the intervention and control groups were 4.4% in full recovery rates at three weeks (86.4% v 90.8%), 2.2% in all cause mortality rates (3.5% v 1.3%), and 0.7% in hospital admission rates (7.2% v 6.5%). The odds of full recovery at three weeks, and the odds of mortality and hospital admission at any point did not significantly differ between groups.

CONCLUSIONS

CRP POCT for suspected lower respiratory tract infection safely reduced antibiotic prescribing compared with usual care in nursing home residents. The findings suggest that implementing CRP POCT in nursing homes might contribute to reduced antibiotic use in this setting and help to combat antibiotic resistance.

TRIAL REGISTRATION

Netherlands Trial Register NL5054.

Treatment Response Biomarkers in Asthma and COPD

Chronic obstructive pulmonary disease (COPD) and asthma are two of the most common chronic diseases worldwide. Both diseases are heterogenous and complex, and despite their similarities, they differ in terms of pathophysiological and immunological mechanisms. Mounting evidence supports the presence of several phenotypes with various responses to treatment. A systematic and thorough assessment concerning the diagnosis of both asthma and COPD is crucial to the clinical management of the disease. The identification of different biomarkers can facilitate targeted treatment and monitoring. Thanks to the presence of numerous immunological studies, our understanding of asthma phenotypes and mechanisms of disease has increased markedly in the last decade, and several treatments with monoclonal antibodies are available. There are compelling data that link eosinophilia with an increased risk of COPD exacerbations but a greater treatment response and lower all-cause mortality. Eosinophilia can be considered as a treatable trait, and the initiation of inhaled corticosteroid in COPD patients with eosinophilia is supported in many studies. In spite of advances in our understanding of both asthma and COPD in terms pathophysiology, disease mechanisms, biomarkers, and response to treatment, many uncertainties in the management of obstructive airways exist.

Procalcitonin for individualizing antibiotic treatment: an update with a focus on COVID-19

Procalcitonin (PCT) is useful for differentiating between viral and bacterial infections and for reducing the unnecessary use of antibiotics. As the rise of antimicrobial resistance reaches “alarming” levels according to the World Health Organization, the importance of using biomarkers, such as PCT to limit unnecessary antibiotic exposure has further increased. Randomized trials in patients with respiratory tract infections have shown that PCT has prognostic implications and its use, embedded in stewardship protocols, leads to reductions in the use of antibiotics in different clinical settings without compromising clinical outcomes. However, available data are heterogeneous and recent trials found no significant benefit. Still, from these trials, we have learned several key considerations for the optimal use of PCT, which depend on the clinical setting, severity of presentation, and pretest probability for bacterial infection. For patients with respiratory infections and sepsis, PCT can be used to determine whether to initiate antimicrobial therapy in low-risk settings and, together with clinical data, whether to discontinue antimicrobial therapy in certain high-risk settings. There is also increasing evidence regarding PCT-guided therapy in patients with coronavirus disease 2019 (COVID-19). This review provides an up-to-date overview of the use of PCT in different clinical settings and diseases, including a discussion about its potential to improve the care of patients with COVID-19.

Evaluation of procalcitonin-guided antimicrobial stewardship in patients admitted to hospital with COVID-19 pneumonia

Background

Procalcitonin is a biomarker that may be able to identify patients with COVID-19 pneumonia who do not require antimicrobials for bacterial respiratory tract co-infections.

Objectives

To evaluate the safety and effectiveness of a procalcitonin-guided algorithm in rationalizing empirical antimicrobial prescriptions in non-critically ill patients with COVID-19 pneumonia.

Methods

Retrospective, single-site, cohort study in adults hospitalized with confirmed or suspected COVID-19 pneumonia and receiving empirical antimicrobials for potential bacterial respiratory tract co-infection. Regression models were used to compare the following outcomes in patients with and without procalcitonin testing within 72 h of starting antimicrobials: antimicrobial consumption (DDD); antimicrobial duration; a composite safety outcome of death, admission to HDU/ICU or readmission to hospital within 30 days; and length of admission. Procalcitonin levels of ≤0.25 ng/L were interpreted as negatively predictive of bacterial co-infection. Effects were expressed as ratios of means (ROM) or prevalence ratios (PR) accordingly.

Results

259 patients were included in the final analysis. Antimicrobial use was lower in patients who had procalcitonin measured within 72 h of starting antimicrobials: mean antimicrobial duration 4.4 versus 5.4 days, adjusted ROM 0.7 (95% CI 0.6-0.9); mean antimicrobial consumption 6.8 versus 8.4 DDD, adjusted ROM 0.7 (95% CI 0.6-0.8). Both groups had similar composite safety outcomes (adjusted PR 0.9; 95% CI 0.6-1.3) and lengths of admission (adjusted ROM 1.3; 95% CI 0.9-1.6).

Conclusions

A procalcitonin-guided algorithm may allow for the safe reduction of antimicrobial usage in hospitalized non-critically ill patients with COVID-19 pneumonia.