Impact of Procalcitonin Guidance with an Educational Program on Management of Adults Hospitalized with Pneumonia

Procalcitonin Monitoring and Antibiotic Duration in Presumed Lower Respiratory Tract Infections: A Propensity Score-Matched Cohort Across the Veterans Health Administration

Background

Randomized controlled trials have shown that procalcitonin-guided algorithms can reduce antibiotic duration for lower respiratory tract infections (LRTIs). The goal of this study was to compare antibiotic duration for LRTIs with and without procalcitonin testing in real-life practice.

Methods

This retrospective cohort study included all acute care hospital admissions for presumed LRTIs between 1/2018 and 12/2021 at 81 Veterans Affairs facilities with on-site procalcitonin testing. The exposure was procalcitonin testing; the primary outcome was antibiotic duration. We used 1:1 nearest-neighbor propensity score matching to estimate the difference in outcome between procalcitonin-tested and nontested patients.

Results

A total of 35 610 patients with LRTIs were included (6015 [16.9%] with procalcitonin testing; 29 595 [83.1%] without testing). In tested patients, the median number of procalcitonin levels checked (interquartile range) was 2 (1-3). The mean antibiotic duration was 10.0 days in the procalcitonin group compared with 8.3 days in nontested patients (unadjusted difference, 1.7 days; P < .0001). After propensity score matching with 3903 pairs, antibiotic duration remained greater in the procalcitonin group (9.6 days vs 9.2 days; P < .0001). In a subgroup analysis of 2241 tested patients with a procalcitonin value at the standard threshold for antibiotic discontinuation, antibiotic duration was shorter in tested vs nontested patients, with a mean difference of 0.1 days (P < .01).

Conclusions

In this retrospective propensity-matched cohort of patients with presumed LRTIs across a geographically diverse group of hospitals, patients who underwent procalcitonin testing did not have a meaningful reduction in antibiotic duration compared with those who were not tested. Poor implementation of procalcitonin testing may have undermined its effectiveness.

Use of biomarkers to individualize antimicrobial therapy duration: a narrative review

BACKGROUND

Reducing the overuse of antimicrobials is imperative for the sake of minimizing antimicrobial-associated adverse effects, optimizing resource utilization, and curtailing the rise in multidrug-resistant organisms. Biomarkers reflect the host responses to infection and may assist with minimizing unnecessary antimicrobial usage.

OBJECTIVES

To review the literature pertaining to the performance of biomarkers specifically used to guide the duration of antimicrobial therapy (AMT).

SOURCES

Randomized controlled trials, observational studies, and meta-analyses assessing biomarker-guided approaches to AMT decision-making and their impact on the duration of therapy were reviewed.

CONTENT

Several randomized controlled trials and real-world observational studies have shown that a procalcitonin (PCT)-guided strategy can help clinicians individualize the duration of AMT, particularly among non-critically ill patients hospitalized with suspected respiratory tract infections when using a PCT cut-off value of <0.25 μg/L and critically ill patients with respiratory tract infections or undifferentiated sepsis when using a PCT cut-off value of <0.5 μg/L or ≥80% decline in the peak level. C-reactive protein is a non-specific marker of inflammation that may also assist with an early discontinuation of AMT; however, data are limited. Haematological biomarkers are prone to variance between individuals and are often influenced by medications and non-infectious conditions, making them less reliable for the purposes of AMT decision-making. Novel biomarkers such as multi-protein signatures and host gene expression tests have shown promise as tools to better differentiate between bacterial and non-bacterial infections; clinical studies are needed to determine whether they can be used to help optimize the duration of AMT.

IMPLICATIONS

Studies have demonstrated that a PCT-guided strategy, when utilized appropriately, can help guide clinicians to individualize and often reduce the duration of AMT, especially in patients hospitalized with respiratory tract infections and those admitted to the intensive care unit with suspected respiratory tract infections or sepsis. The impact of utilizing other biomarkers is less clear and requires further study.

Antimicrobial Stewardship Using Biomarkers: Accumulating Evidence for the Critically Ill

This review aims to summarize current progress in the management of critically ill, using biomarkers as guidance for antimicrobial treatment with a focus on antimicrobial stewardship. Accumulated evidence from randomized clinical trials (RCTs) and observational studies in adults for the biomarker-guided antimicrobial treatment of critically ill (mainly sepsis and COVID-19 patients) has been extensively searched and is provided. Procalcitonin (PCT) is the best studied biomarker; in the majority of randomized clinical trials an algorithm of discontinuation of antibiotics with decreasing PCT over serial measurements has been proven safe and effective to reduce length of antimicrobial treatment, antibiotic-associated adverse events and long-term infectious complications like infections by multidrug-resistant organisms and Clostridioides difficile. Other biomarkers, such as C-reactive protein and presepsin, are already being tested as guidance for shorter antimicrobial treatment, but more research is needed. Current evidence suggests that biomarkers, mainly procalcitonin, should be implemented in antimicrobial stewardship programs even in the COVID-19 era, when, although bacterial coinfection rate is low, antimicrobial overconsumption remains high.

Usefulness of procalcitonin (PCT), C-reactive protein (CRP), and white blood cell (WBC) levels in the differential diagnosis of acute bacterial, viral, and mycoplasmal respiratory tract infections in children

Background

There is a lack of studies comparing PCT, CRP and WBC levels in the differential diagnosis of acute bacterial, viral, and mycoplasmal respiratory tract infections. It is necessary to explore the correlation between above markers and different types of ARTI.

Methods

108 children with confirmed bacterial infection were regarded as group A, 116 children with virus infection were regarded as group B, and 122 children with mycoplasmal infection were regarded as group C. The levels of PCT, CRP and WBC of the three groups were detected and compared.

Results

The levels of PCT, CRP and WBC in group A were significantly higher than those in groups B and C (p < 0.05). The positive rate of combined detection of PCT, CRP and WBC was significant higher than that of single detection. There was no significant difference in PCT, CRP and WBC levels between the group of G⁺ bacterial infection and G⁻ bacterial infection (p > 0.05). ROC curve results showed that the AUC of PCT, CRP and WBC for the diagnosis of bacterial respiratory infections were 0.65, 0.55, and 0.58, respectively.

Conclusions

PCT, CRP and WBC can be combined as effective indicators for the identification of acute bacterial or no-bacterial infections in children. The levels of PCT and CRP have higher differential diagnostic value than that of WBC in infection, and the combined examination of the three is more valuable in clinic.

Evaluation of a Pharmacist-Driven Procalcitonin Protocol for Lower Respiratory Tract Infections Using a Clinical Decision Support System

Purpose: Procalcitonin (PCT) may be an effective biomarker in the management of lower respiratory tract infections (LRTI) when combined with antimicrobial stewardship support. We assessed the impact of a PCT protocol with clinical pharmacy support for LRTI using a clinical decision support system (CDSS) for monitoring. Methods: This was a single-center retrospective cohort study conducted at a large, nonteaching hospital in Nashville, TN. All patients who met eligibility requirements and were initiated on the PCT protocol for a suspected LRTI between February and March 2018 were included and matched to historical control patients from 2016 to 2017 on a 1:1 basis based on antibiotics, indication, and time of year. Results: During this 2-month period, a total of 126 patients met eligibility requirements for inclusion in the PCT group and were matched to historical control patients. Patients in the PCT group received decreased median antibiotic days of therapy (DOT) compared to controls (11 vs 14, P = .004). There was no change in median length of stay (LOS) between groups. The acceptance rate for patient-specific antibiotic de-escalation recommendations from the clinical pharmacist was 62.5%. Conclusion: PCT protocols that utilize clinical pharmacist interpretation and a CDSS may be an effective intervention of the antimicrobial stewardship program (ASP) for decreasing antibiotic DOT for LRTI.

Decreased antibiotic exposure using a procalcitonin protocol for respiratory infections and sepsis in US community hospitals (ProCommunity)

OBJECTIVE

Antibiotic overuse leading to antimicrobial resistance is a global public health concern. Clinical trials have demonstrated that procalcitonin-based decision-making for antibiotic therapy can safely decrease inappropriate antibiotic use in patients with respiratory infections and sepsis, but real-world data are scarce. This study sought to assess the impact of a procalcitonin-based antibiotic stewardship program (protocol plus education) on antibiotic use in community hospitals.

METHODS

An observational, retrospective, matched cohort study was conducted. Eligible patients treated in hospitals with a procalcitonin-based protocol plus education (Procalcitonin cohort hospitals) were matched to patients admitted to facilities without procalcitonin testing (Control cohort hospitals) using a 1:2 ratio. The Control hospitals were facilities where procalcitonin testing was not available on site. Patient matching was based on: (1) age, (2) gender, (3) admission diagnosis code using groupings of the International Classification of Diseases, 10th Revision, (4) whether patients were admitted to the intensive care unit, and (5) whether a blood culture test was performed. Procalcitonin cohort hospitals implemented a quality improvement initiative, where procalcitonin was available, used regularly, and clinicians (physicians and pharmacists) were educated on its use.

RESULTS

After adjustment, patients in the Procalcitonin cohort had 1.47 fewer antibiotic days (9.1 vs. 8.5 days, 95%CI: -2.72; -0.22, p = .021). There was no difference in length of stay or adverse clinical outcomes except for increase in acute kidney injury (odds ratio = 1.26, 95%CI: 1.01; 1.58, p = .038).

CONCLUSIONS

Patients with respiratory infections and sepsis in hospitals utilizing a procalcitonin-based protocol coupled with education received fewer days of antibiotic therapy.

New guidelines for severe community-acquired pneumonia

PURPOSE OF REVIEW

We highlight the recent advances in the guidelines for treating patients with severe community-acquired pneumonia (sCAP).

RECENT FINDINGS

sCAP is a significant cause of hospital admissions. We performed an extensive review of the literature, covering studies from the last several years, to summarise the most important points in the diagnosis and treatment of patients hospitalised with sCAP.

SUMMARY

sCAP is associated with a high clinical burden. Therefore, deep knowledge is necessary for its management. In general, diagnosis, treatment and management are based on many published guidelines. However, the mortality rate is still unacceptably high, indicating the need for clear recommendations in the management of patients with sCAP. The choice of empirical antibiotic therapy for sCAP depends on multiple factors, such as national and local antimicrobial susceptibility data and the characteristics of the patients, including their risk factors for acquiring infections caused by multidrug-resistant pathogens. Currently, there are several published international guidelines. The aim of this review is to explore the areas that require further knowledge and new recommendations for current clinical practice.

An investigation of the effects of procalcitonin testing on antimicrobial prescribing in respiratory tract infections in an Irish university hospital setting: a feasibility study

BACKGROUND

Diagnostic uncertainty and a high prevalence of viral infections present unique challenges for antimicrobial prescribing for respiratory tract infections (RTIs). Procalcitonin (PCT) has been shown to support prescribing decisions and reduce antimicrobial use safely in patients with RTIs, but recent study results have been variable.

METHODS

We conducted a feasibility study of the introduction of PCT testing in patients admitted to hospital with a lower RTI to determine if PCT testing is an effective and worthwhile intervention to introduce to support the existing antimicrobial stewardship (AMS) programme and safely decrease antimicrobial prescribing in patients admitted with RTIs.

RESULTS

A total of 79 patients were randomized to the intervention PCT-guided treatment group and 40 patients to the standard care respiratory control group. The addition of PCT testing led to a significant decrease in duration of antimicrobial prescriptions (mean 6.8 versus 8.9 days, P = 0.012) and decreased length of hospital stay (median 7 versus 8 days, P = 0.009) between the PCT and respiratory control group. PCT did not demonstrate a significant reduction in antimicrobial consumption when measured as DDDs and days of therapy.

CONCLUSIONS

PCT testing had a positive effect on antimicrobial prescribing during this feasibility study. The successful implementation of PCT testing in a randomized controlled trial requires an ongoing comprehensive education programme, greater integration into the AMS programme and delivery of PCT results in a timely manner. This feasibility study has shown that a larger randomized controlled trial would be beneficial to further explore the positive aspects of these findings.

Acute Exacerbations of Chronic Obstructive Pulmonary Disease With a Low Procalcitonin Concentration: Impact of Antibiotic Therapy

BACKGROUND

Patients admitted with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) often are prescribed antibiotics. Studies have shown that the use of procalcitonin (PCT) to guide the decision to initiate antibiotic therapy in AECOPD has resulted in less antibiotic use and similar outcomes compared with standard of care. We evaluated patients with AECOPD and low PCT concentrations to determine whether antibiotic therapy was associated with improved outcomes.

METHODS

We retrospectively evaluated adult patients admitted with AECOPD who had a peak PCT concentration <0.25 µg/mL. Patients were evaluated based on their antibiotic exposure: ≤24 hours vs >24 hours. We also evaluated outcomes based upon the duration of azithromycin therapy: ≤24 hours vs >24 hours. The primary outcome was all-cause 30-day readmissions. Secondary outcomes included length of stay (LOS) and COPD-related 30-day readmissions.

RESULTS

One hundred sixty-one and 195 patients received ≤24 hours vs >24 hours of antibiotic therapy, respectively. The cohort with ≤24 hours of antibiotics had a shorter LOS (2.8 vs 3.7 days; P = .01). There were no differences in all-cause 30-day readmissions (15.5% vs 17.4%; P = .63) or COPD-related 30-day readmissions (11.2% vs 12.3%; P = .74). Additionally, patients receiving ≤24 hours of azithromycin had a shorter LOS (3.0 vs 3.8 days; P = .002) and there were no differences in all-cause 30-day readmissions (16.2% vs 17.1%; P = .82) or COPD-related 30-day readmissions (11.9% vs 11.6%; P = .94).

CONCLUSIONS

For adult patients hospitalized with nonsevere AECOPD and low PCT concentrations, antibiotic therapy beyond 24 hours did not improve outcomes.

The role of procalcitonin in differential diagnosis between acute radiation pneumonitis and bacterial pneumonia in lung cancer patients receiving thoracic radiotherapy

Acute Radiation Pneumonitis (ARP) is one of the most common dose-limiting toxicities of thoracic radiotherapy. The accurate diagnosis of ARP remains a challenge because of the lack of a rapid biomarker capable of differentiating ARP from bacterial pneumo (BP). The aim of this study was to investigate the potential usefulness of procalcitonin (PCT) in the differential diagnosis of ARP and BP. Lung cancer patients who had undergone thoracic radiotherapy within 6 months and were admitted to hospital for ARP or BP were retrospectively analyzed. The serum levels of PCT, C-reactive protein (CRP) and white blood cells (WBC) were compared between the two groups. Receiver operating characteristic (ROC) curve was used to assess the diagnostic value of PCT, CRP and WBC in the differential diagnosis of ARP and BP and determine the best cut-off values. One hundred eighteen patients were included. Among them, seventy-seven patients were diagnosed with ARP, and 41 patients were diagnosed with BP. The PCT concentrations for patients diagnosed with ARP group were significantly lower than those in the BP group (P < 0.001). There were no differences in CRP and WBC between the two groups. The areas under the ROC curves (AUC) for PCT, CRP and WBC were 0.745, 0.589 and 0.578, respectively. The best cutoff values of PCT, CRP and WBC were 0.47 μg/L, 54.5 mg/L and 9.9 × 10⁹/L, respectively. Low serum PCT levels are associated with ARP. PCT is a useful biomarker to distinguish ARP from BP.

Impact of Procalcitonin Levels Combined with Active Intervention on Antimicrobial Stewardship in a Community Hospital

BACKGROUND

Procalcitonin (PCT) guidance alone or in conjunction with antibiotic stewardship programs (ASP) has been shown to reduce antibiotic utilization and duration of therapy without adversely affecting patient outcomes.

METHODS

In a community hospital, we investigated the impact of PCT with ASP recommendations on length of stay (LOS), length of antimicrobial therapy (LOT) after ASP recommendation, and total LOT over a one-year period. Adult patients with at least one PCT value and concomitant ASP recommendations were included. Patients were grouped by provider ASP compliance and further stratified by normal versus elevated PCT values. No specific PCT algorithm was utilized.

RESULTS

A total of 857 patients were retrospectively analyzed. Physicians complied with 73.7% of ASP recommendations. There were no significant differences in LOS based on ASP compliance. Mean LOT after ASP recommendations and mean total LOT were significantly shorter (2.5 vs. 3.9 days, p<0.0001 and 5.1 vs. 6.6 days, p<0.0001, respectively) in the ASP complier group. When stratified by initial PCT levels, ASP compliers for patients with normal PCT levels had the shortest duration of therapy for all groups; among patients with elevated PCT levels, the duration of therapy was significantly shorter in the ASP compliant group (5.79 vs. 7.12 days, p<0.0111). When controlling for baseline differences in initial PCT levels, LOS was found to be marginally shorter in the ASP compliant group (p = 0.076).

CONCLUSIONS

PCT-guided ASP physician recommendations, when accepted by providers, led to reduction in antimicrobial LOT in a community hospital. This benefit was extended across patient groups irrespective of initial PCT levels.

Systematic Review and Meta-analysis of the Efficacy of Short-Course Antibiotic Treatments for Community-Acquired Pneumonia in Adults

The duration of therapy for community-acquired pneumonia (CAP) remains undefined. We sought to investigate whether short-course antibiotic treatment for CAP is associated with favorable clinical outcomes in adult patients. We systematically searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for studies comparing the effectiveness and safety between treatment regimens administered for ≤6 days and ≥7 days. We defined treatment for ≤6 days as short-course treatment and treatment for ≥7 days as long-course treatment. Twenty-one clinical trials (4,861 clinically evaluable patients) were included, and 19 out of 21 trials were randomized. Clinical cure was similar between the compared groups (4,069 patients, risk ratio [RR] = 0.99 [95% confidence interval {CI}, 0.97 to 1.01]), irrespective of patient setting (RR = 0.98 [95% CI, 0.96 to 1.00] for the outpatient setting and RR = 1.00 [95% CI, 0.92 to 1.09] for the inpatient setting) or severity of pneumonia (RR = 1.05 [95% CI, 0.96 to 1.14]). Also, relapses were similar between the short- and long-course treatment groups (1,923 patients, RR = 0.67 [95% CI, 0.30 to 1.46]). Short-course treatment was associated with fewer serious adverse events (1,923 patients, RR = 0.73 [95% CI, 0.55 to 0.97]) and, importantly, resulted in lower mortality than long-course treatment (2,802 patients, RR = 0.52 [95% CI, 0.33 to 0.82]). In CAP, short-course antibiotic treatment (≤6 days) is as effective as and potentially superior to, in terms of mortality and serious adverse events, longer-course treatment.