Biomarker-guided antibiotic therapy-strengths and limitations

Prevalence and predictors of antibiotic prescription among patients hospitalized with viral lower respiratory tract infections in Southern Province, Sri Lanka

BACKGROUND

Antimicrobial overprescription is common for lower respiratory tract infections (LRTI), as viral and bacterial infections generally present with similar clinical features. Overprescription is associated with downstream antimicrobial resistance. This study aims to identify the prevalence and predictors of antibiotic prescription among patients hospitalized with viral LRTI.

METHODS

A prospective cohort study was conducted among patients aged ≥1 year hospitalized with viral LRTI in a tertiary care hospital in Southern Province, Sri Lanka from 2018-2021. Demographic, clinical, and laboratory data were recorded. Nasopharyngeal and blood samples were collected for multiplex polymerase chain reaction testing for 21 respiratory pathogens and procalcitonin (PCT) detection, respectively. Demographic and clinical features associated with antibiotic prescription were identified using Chi Square and t-tests; significant variables (p<0.05) were further included in multivariable logistic regression models. The potential impact of biomarker testing on antibiotic prescription was simulated using standard c-reactive protein (CRP) and PCT cut-offs.

RESULTS

Of 1217 patients enrolled, 438 (36.0%) had ≥1 respiratory virus detected, with 48.4% of these patients being male and 30.8% children. Influenza A (39.3%) and human rhinovirus/ enterovirus (28.3%) were most commonly detected. A total of 114 (84.4%) children and 266 (87.8%) adults with respiratory viruses were treated with antibiotics. Among children, neutrophil percentage (median 63.6% vs 47.6%, p = 0.04) was positively associated with antibiotic prescription. Among adults, headache (60.6% vs 35.1%, p = 0.003), crepitations/crackles (55.3% vs 21.6%, p<0.001), rhonchi/wheezing (42.9% vs 18.9%, p = 0.005), and chest x-ray opacities (27.4% vs 8.1%, p = 0.01) were associated with antibiotic prescription. Access to CRP and procalcitonin test results could have potentially decreased inappropriate antibiotic prescription in this study by 89.5% and 83.3%, respectively.

CONCLUSIONS

High proportions of viral detection and antibiotic prescription were observed among a large inpatient cohort with LRTI. Increased access to point-of-care biomarker testing may improve antimicrobial prescription.

Point Prevalence Survey of Antimicrobial Prescription and Consumption in a Nigerian Tertiary Hospital: A Gateway to the Antimicrobial Stewardship Program

BACKGROUND

Antimicrobial stewardship is an important action plan for curbing the rising trend of antimicrobial resistance (AMR). Surveillance of antimicrobial use and consumption is needed as baseline data and for monitoring the impact of antimicrobial stewardship interventions. The survey was done to understand the burden of AMR, in view of establishing an antimicrobial stewardship program in our hospital.

METHODS

A point prevalence survey (PPS) of antimicrobial use and consumption was conducted on all inpatients admitted before 8.00 am on the days of the survey using a standardized questionnaire. The collected data were entered online into the Global PPS web-based application (www.global-pps.com), for analysis.

RESULT

Of the 178 patients admitted during the survey period, 50.6% were on one or more antimicrobial agents. All the patients in adult intensive care units were on antibiotics (100%), followed by neonatal intensive care units (83.3%), with the least being adult medical wards (39.4%). Beta-lactam antibiotics were the most frequently prescribed antimicrobial for various infections, especially skin and soft tissue infections, 41.3%, which were the most common diagnoses treated with antibiotics. The infection was mostly community-acquired (81.6%), of which 94.9% were treated empirically. There was no written guideline in existence.

CONCLUSION

The present study revealed a poor prescribing habit because of a high rate of empirical treatment. The need for antimicrobial stewardship cannot be overemphasized as it will help streamline and improve the prescribing pattern.

Biomarkers: Are They Useful in Severe Community-Acquired Pneumonia?

Community acquired pneumonia (CAP) is a prevalent infectious disease often requiring hospitalization, although its diagnosis remains challenging as there is no gold standard test. In severe CAP, clinical and radiologic criteria have poor sensitivity and specificity, and microbiologic documentation is usually delayed and obtained in less than half of sCAP patients. Biomarkers could be an alternative for diagnosis, treatment monitoring and establish resolution. Beyond the existing evidence about biomarkers as an adjunct diagnostic tool, most evidence comes from studies including CAP patients in primary care or emergency departments, and not only sCAP patients. Ideally, biomarkers used in combination with signs, symptoms, and radiological findings can improve clinical judgment to confirm or rule out CAP diagnosis, and may be valuable adjunctive tools for risk stratification, differentiate viral pneumonia and monitoring the course of CAP. While no single biomarker has emerged as an ideal one, CRP and PCT have gathered the most evidence. Overall, biomarkers offer valuable information and can enhance clinical decision-making in the management of CAP, but further research and validation are needed to establish their optimal use and clinical utility.

Antimicrobial prescribing in a secondary care setting during the COVID-19 pandemic

Background

Increased antimicrobial resistance patterns lead to limited options for antimicrobial agents, affecting patient health and increasing hospital costs.

Objectives

To investigate the antimicrobial prescribing patterns at two district hospitals in Northern Ireland before and during the COVID-19 pandemic.

Methods

A mixed prospective-retrospective study was designed to compare pre- and during pandemic antimicrobial prescribing data in both hospitals using a Global Point Prevalence Survey.

Results

Of the 591 patients surveyed in both hospitals, 43.8% were treated with 402 antimicrobials. A total of 82.8% of antimicrobial prescriptions were for empirical treatment. No significant difference existed in numbers of patients treated or antimicrobials used before and during the pandemic. There was a slight decrease of 3.3% in the compliance rate with hospital antimicrobial guidelines during the pandemic when compared with the pre-pandemic year of 2019, when it was 69.5%. Treatment based on patients' biomarker data also slightly decreased from 83.5% pre-pandemic (2019) to 81.5% during the pandemic (2021).

Conclusions

There was no overall significant impact of the pandemic on the antimicrobial prescribing patterns in either hospital when compared with the pre-pandemic findings. The antimicrobial stewardship programmes would appear to have played an important role in controlling antimicrobial consumption during the pandemic.

Urinary tract infections: a review of the current diagnostics landscape

Urinary tract infections are the most common bacterial infections worldwide. Infections can range from mild, recurrent (rUTI) to complicated (cUTIs), and are predominantly caused by uropathogenic Escherichia coli (UPEC). Antibiotic therapy is important to tackle infection; however, with the continued emergence of antibiotic resistance there is an urgent need to monitor the use of effective antibiotics through better stewardship measures. Currently, clinical diagnosis of UTIs relies on empiric methods supported by laboratory testing including cellular analysis (of both human and bacterial cells), dipstick analysis and phenotypic culture. Therefore, development of novel, sensitive and specific diagnostics is an important means to rationalise antibiotic therapy in patients. This review discusses the current diagnostic landscape and highlights promising novel diagnostic technologies in development that could aid in treatment and management of antibiotic-resistant UTIs.

How to use biomarkers of infection or sepsis at the bedside: guide to clinicians

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. In this context, biomarkers could be considered as indicators of either infection or dysregulated host response or response to treatment and/or aid clinicians to prognosticate patient risk. More than 250 biomarkers have been identified and evaluated over the last few decades, but no biomarker accurately differentiates between sepsis and sepsis-like syndrome. Published data support the use of biomarkers for pathogen identification, clinical diagnosis, and optimization of antibiotic treatment. In this narrative review, we highlight how clinicians could improve the use of pathogen-specific and of the most used host-response biomarkers, procalcitonin and C-reactive protein, to improve the clinical care of patients with sepsis. Biomarker kinetics are more useful than single values in predicting sepsis, when making the diagnosis and assessing the response to antibiotic therapy. Finally, integrated biomarker-guided algorithms may hold promise to improve both the diagnosis and prognosis of sepsis. Herein, we provide current data on the clinical utility of pathogen-specific and host-response biomarkers, offer guidance on how to optimize their use, and propose the needs for future research.

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.

Sepsis and antibiotics: When should we deploy a parachute?

In sepsis and septic shock, guidelines recommend administering antimicrobial therapy within the first hour following diagnosis. This recommendation is based on observational studies suggesting that early antimicrobial therapy is associated with improved outcomes. Consequently, front-line physicians are under pressure to quickly decide on the need for antibiotics in patients for whom the diagnosis of sepsis remains uncertain. However, overuse of antibiotics is associated with emergence of multidrug-resistant bacteria, which constitutes a major health issue worldwide. Front-line physicians may be thought to have been responsible for antibiotic overuse in the same patients. This article reports the situation of physicians who are criticised for using unnecessarily antibiotics or those who are criticised for not timeously using antibiotics; it then discusses several options to help the clinician at the bedside.

Impact of Delayed Time to Antibiotics in Medical and Surgical Necrotizing Enterocolitis

This study investigated whether delayed receipt of antibiotics in infants with necrotizing enterocolitis (NEC) is associated with disease severity. In this retrospective, single-center cohort study of infants diagnosed with NEC over 4 years, we compared the timing of antibiotic administration in infants (time order placed to time of receipt) in medical and surgical NEC. Cases were independently reviewed, then various clinical factors were compared. Of 46 suspected cases, 25 were confirmed by a panel of radiologists with good interrater reliability (ICC 0.657; p < 0.001). Delays in antibiotic receipt were 1.7× greater in surgical than medical NEC cases (p = 0.049). Every hour after order entry increased the adjusted odds of surgical NEC by 2.4 (1.08−5.23; p = 0.032). Delayed antibiotic receipt was more common in infants with surgical than medical NEC. Larger studies will be needed to investigate if optimizing antibiotic expediency could improve intestinal outcomes.

Optimal Predictors of Postoperative Complications After Gastrectomy: Results from the Procalcitonin and C-reactive Protein for the Early Diagnosis of Anastomotic Leakage in Esophagogastric Surgery (PEDALES) Study

BACKGROUND

The aim of this study was to define whether procalcitonin (PCT) is an earlier and more accurate predictor than C-reactive protein (CRP) for anastomotic leakage (AL) and major infective complications (MICs).

METHODS

This was a prospective multicentric observational study conducted in three Italian centers, including all patients undergoing gastrectomy from May 2016 to April 2021. The endpoint was the assessment of the discrimination and accuracy achieved by the PCT and CRP values measured from POD1 to POD7 for predicting the occurrence of AL and MICs. Accuracy was assessed by calculating the area under the receiver operating curve (AUROC) values and Youden's statistics. Two charts were created for risk stratification during the postoperative course.

RESULTS

The rate of AL was 4.6%, with a median day of occurrence on POD5 (range 3-26). The overall rate of major infective complications was 19.9%, with a median day of occurrence on POD6 (range 2-30). PCT showed a significant association with AL on POD6 and POD7 and a significant association with MICs on POD2, while CRP values showed a significant association with AL on POD4 and a significant association with MICs on POD1. No difference in the prediction of AL was observed between PCT and CRP, while CRP was found to be a superior predictor of major infective complications on POD5 (p = 0.024) and POD7 (p = 0.035).

CONCLUSIONS

PCT was not superior to CRP as an early predictor of AL and major infective complications after gastrectomy. CRP should be used as the reference screening postoperative marker.

Current Status of Antibiotic Stewardship and the Role of Biomarkers in Antibiotic Stewardship Programs

The importance of antibiotic stewardship is increasingly emphasized in accordance with the increasing incidences of multidrug-resistant organisms and accompanying increases in disease burden. This review describes the obstacles in operating an antibiotic stewardship program (ASP), and whether the use of biomarkers within currently available resources can help. Surveys conducted around the world have shown that major obstacles to ASPs are shortages of time and personnel, lack of appropriate compensation for ASP operation, and lack of guidelines or appropriate manuals. Sufficient investment, such as the provision of full-time equivalent ASP practitioners, and adoption of computerized clinical decision systems are useful measures to improve ASP within an institution. However, these methods are not easy in terms of both time commitments and cost. Some biomarkers, such as C-reactive protein, procalcitonin, and presepsin are promising tools in ASP due to their utility in diagnosis and forecasting the prognosis of sepsis. Recent studies have demonstrated the usefulness of algorithmic approaches based on procalcitonin level to determine the initiation or discontinuation of antibiotics, which would be helpful in decreasing antibiotics use, resulting in more appropriate antibiotics use.

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.

ACCURACY OF C-REACTIVE PROTEIN AND PROCALCITONIN FOR DIAGNOSING BACTERIAL INFECTIONS AMONG SUBJECTS WITH PERSISTENT FEVER IN THE TROPICS

Background

In low-resource settings, inflammatory biomarkers can help identify patients with acute febrile illness who do not require antibiotics. Their use has not been studied in persistent fever (defined as fever lasting for ≥7 days at presentation).

Methods

C-reactive protein (CRP) and procalcitonin (PCT) levels were measured in stored serum samples of patients with persistent fever prospectively enrolled in Cambodia, the Democratic Republic of Congo, Nepal, and Sudan. Diagnostic accuracy was assessed for identifying all bacterial infections and the subcategory of severe infections judged to require immediate antibiotics.

Results

Among 1838 participants, CRP and PCT levels were determined in 1777 (96.7%) and 1711 (93.1%) samples, respectively, while white blood cell (WBC) count was available for 1762 (95.9%). Areas under the receiver operating characteristic curve for bacterial infections were higher for CRP (0.669) and WBC count (0.651) as compared with PCT (0.600; P <.001). Sensitivity for overall and severe bacterial infections was 76.3% (469/615) and 88.2% (194/220) for CRP >10 mg/L, 62.4% (380/609) and 76.8% (169/220) for PCT >0.1 µg/L, and 30.5% (184/604) and 43.7% (94/215) for WBC >11 000/µL, respectively. Initial CRP level was <10 mg/L in 45% of the participants who received antibiotics at first presentation.

Conclusions

In patients with persistent fever, CRP and PCT showed higher sensitivity for bacterial infections than WBC count, applying commonly used cutoffs for normal values. A normal CRP value excluded the vast majority of severe infections and could therefore assist in deciding whether to withhold empiric antibiotics after cautious clinical assessment.

Challenges of Antibiotic Stewardship in the Pediatric and Neonatal Intensive Care Units

The goals of antimicrobial stewardship programs (ASPs) are to optimize antimicrobial prescribing habits in order to improve patient outcomes, reduce antimicrobial resistance, and reduce hospital costs. Multiple society-endorsed guidelines and government policies reinforce the importance of ASP implementation. Effective antimicrobial stewardship can impact unique patients, hospitals, and societal antibiotic-resistance burden. The role and subsequent success of these programs has largely been reported in the adult population. Pediatric and neonatal intensive care units present unique challenges for traditional antimicrobial stewardship approaches. The purpose of this review article is to explore the challenges of appropriate antibiotic use in the pediatric and neonatal intensive care units and to summarize strategies ASPs can use to overcome these challenges. These problems include non-specific disease presentations, limited evidence for definitive treatment durations in many pediatric infections, fewer pediatric-trained infectious disease physicians, and applicability of intensive laboratory obtainment, collection, and interpretation. Additionally, many ASP implementation studies evaluating the efficacy of ASPs exclude the PICU and NICU. Areas of focus for pediatric ASPs should likely include appropriate antibiotic initiation, appropriate antibiotic duration, and appropriate antibiotic de-escalation.

Which Biomarkers Can Be Used as Diagnostic Tools for Infection in Suspected Sepsis?

The diagnosis of infection in patients with suspected sepsis is frequently difficult to achieve with a reasonable degree of certainty. Currently, the diagnosis of infection still relies on a combination of systemic manifestations, manifestations of organ dysfunction, and microbiological documentation. In addition, the microbiologic confirmation of infection is obtained only after 2 to 3 days of empiric antibiotic therapy. These criteria are far from perfect being at least in part responsible for the overuse and misuse of antibiotics, in the community and in hospital, and probably the main drive for antibiotic resistance. Biomarkers have been studied and used in several clinical settings as surrogate markers of infection to improve their diagnostic accuracy as well as in the assessment of response to antibiotics and in antibiotic stewardship programs. The aim of this review is to provide a clear overview of the current evidence of usefulness of biomarkers in several clinical scenarios, namely, to diagnose infection to prescribe antibiotics, to exclude infection to withhold antibiotics, and to identify the causative pathogen to target antimicrobial treatment. In recent years, new evidence with "old" biomarkers, like C-reactive protein and procalcitonin, as well as new biomarkers and molecular tests, as breathomics or bacterial DNA identification by polymerase chain reaction, increased markedly in different areas adding useful information for clinical decision making at the bedside when adequately used. The recent evidence shows that the information given by biomarkers can support the suspicion of infection and pathogen identification but also, and not less important, can exclude its diagnosis. Although the ideal biomarker has not yet been found, there are various promising biomarkers that represent true evolutions in the diagnosis of infection in patients with suspected sepsis.

Evaluation of antibiotic treatment decisions in pediatric intensive care units in Saudi Arabia: A national survey

OBJECTIVE

To describe variables used by Saudi pediatric intensivists to make antibiotic-related decisions for children with suspected severe bacterial infections.

METHODS

We conducted a cross-sectional survey, which was developed using a multi-step methodological approach. The survey included 4 clinical scenarios of the most relevant bacterial infections in pediatric critical care (pneumonia, sepsis, meningitis and intra-abdominal infection). The potential determinants of antibiotic treatment duration addressed in all scenarios included clinical variables (patient characteristics, disease severity), laboratory infection markers, radiologic findings, and pathogens.

RESULTS

The response rate was 65% (55/85). Eight variables (immunodeficiency, 3 months of age, 2 or more organ dysfunctions, Pediatric Risk of Mortality III score >10, leukocytosis, elevated C-reactive protein [CRP], elevated erythrocyte sedimentation rate [ESR], and elevated procalcitonin [PCT]) were associated with prolonging antibiotic treatment duration for all 4 clinical scenarios, with a median increase ranging from 3.0 days (95% confidence interval [CI] 0.5, 3.5, leukocytosis) to 8.8 days (95% CI 5.5, 10.5, immunodeficiency). There were no variables that were consistently associated with shortening antibiotic duration across all scenarios. Lastly, the proportion of physicians who would continue antibiotics for ≥5 days despite a positive viral polymerase chain reaction test result was 67% for pneumonia, 85% for sepsis, 63% for meningitis, and 95% for intra-abdominal infections.

CONCLUSION

Antibiotic-related decisions for critically ill patients are complex and depend on several factors. Saudi pediatric intensivists will use prolonged courses of antibiotics for younger patients, patients with severe clinical picture, and patients with persistently elevated laboratory markers and hospital acquired infections, even when current literature and guidelines do not suggest such practices. Antimicrobial stewardship programs should include interventions to address these misconceptions to ensure the rational use of antibiotics in pediatric intensive care units.

Think Twice before Prescribing Antibiotics for That Swollen Knee: The Influence of Antibiotics on the Diagnosis of Periprosthetic Joint Infection

Periprosthetic joint infection (PJI) is a rare but devastating complication after total joint arthroplasty. An estimated 7-12% of patients have negative cultures despite clear clinical evidence of infection. One oft-cited reason for this occurrence is the administration of antibiotics in the weeks prior to obtaining cultures. This article reviews the influence of antibiotics on the diagnosis of PJI. Specifically, we examine the effect of prophylactic and therapeutic antibiotic administration on the diagnostic accuracy of microbiological cultures as well as serum and synovial biomarkers. We also explore the potential of molecular techniques in overcoming these limitations in patients who have received antibiotics before specimen collection and propose areas for future research.

Vibrational spectroscopic analysis of blood for diagnosis of infections and sepsis: a review of requirements for a rapid diagnostic test

Infections and sepsis represent a growing global burden. There is a widespread clinical need for a rapid, high-throughput and sensitive technique for the diagnosis of infections and detection of invading pathogens and the presence of sepsis. Current diagnostic methods primarily consist of laboratory-based haematology, biochemistry and microbiology that are time consuming, labour- and resource-intensive, and prone to both false positive and false negative results. Current methods are insufficient for the increasing demands on healthcare systems, causing delays in diagnosis and initiation of treatment, due to the intrinsic time delay in sample preparation, measurement, and analysis. Vibrational spectroscopic techniques can overcome these limitations by providing a rapid, label-free and low-cost method for blood analysis, with limited sample preparation required, potentially revolutionising clinical diagnostics by producing actionable results that enable early diagnosis, leading to improved patient outcomes. This review will discuss the challenges associated with the diagnosis of infections and sepsis, primarily within the UK healthcare system. We will consider the clinical potential of spectroscopic point-of-care technologies to enable blood analysis in the primary-care setting.

Antimicrobial Stewardship in the Intensive Care Unit: The Role of Biomarkers, Pharmacokinetics, and Pharmacodynamics

The high prevalence of infectious diseases in the intensive care unit (ICU) and consequently elevated pressure for immediate and effective treatment have led to increased antimicrobial therapy consumption and misuse. Moreover, the emerging global threat of antimicrobial resistance and lack of novel antimicrobials justify the implementation of judicious antimicrobial stewardship programs (ASP) in the ICU. However, even though the importance of ASP is generally accepted, its implementation in the ICU is far from optimal and current evidence regarding strategies such as de-escalation remains controversial. The limitations of clinical guidance for antimicrobial therapy initiation and discontinuation have led to multiple studies for the evaluation of more objective tools, such as biomarkers as adjuncts for ASP. C-reactive protein and procalcitonin can be adequate for clinical use in acute infectious diseases, the latter being the most studied for ASP purposes. Although promising, current evidence highlights challenges in biomarker application and interpretation. Furthermore, the physiological alterations in the critically ill render pharmacokinetics and pharmacodynamics crucial parameters for adequate antimicrobial therapy use. Individual pharmacokinetic and pharmacodynamic targets can reduce antimicrobial therapy misuse and risk of antimicrobial resistance.

Improving target assessment in biomedical research: the GOT-IT recommendations

Academic research plays a key role in identifying new drug targets, including understanding target biology and links between targets and disease states. To lead to new drugs, however, research must progress from purely academic exploration to the initiation of efforts to identify and test a drug candidate in clinical trials, which are typically conducted by the biopharma industry. This transition can be facilitated by a timely focus on target assessment aspects such as target-related safety issues, druggability and assayability, as well as the potential for target modulation to achieve differentiation from established therapies. Here, we present recommendations from the GOT-IT working group, which have been designed to support academic scientists and funders of translational research in identifying and prioritizing target assessment activities and in defining a critical path to reach scientific goals as well as goals related to licensing, partnering with industry or initiating clinical development programmes. Based on sets of guiding questions for different areas of target assessment, the GOT-IT framework is intended to stimulate academic scientists' awareness of factors that make translational research more robust and efficient, and to facilitate academia-industry collaboration.

New perspectives in the antibiotic treatment of mechanically ventilated patients with infections from Gram-negatives

Introduction: Ventilator-associated pneumonia (VAP) is a common and potentially fatal complication of mechanical ventilation that is often caused by multidrug-resistant (MDR) Gram-negative bacteria (GNB). Despite the repurposing of older treatments and the novel antimicrobials, many resistance mechanisms cannot be confronted, and novel therapies are needed.Areas covered: We searched the literature for keywords regarding the treatment of GNB infections in mechanically ventilated patients. This narrative review presents new data on antibiotics and non-antibiotic approaches focusing on Phase 3 trials against clinically significant GNB that cause VAP.Expert opinion: Ceftazidime-avibactam, meropenem-vaborbactam, and imipenem-relebactam stand out as new options for infections by Klebsiella pneumoniae carbapenemase-producing bacteria, whereas ceftolozane-tazobactam adds therapeutic flexibility in Pseudomonas aeruginosa infections with multiple resistance mechanisms. Ceftazidime-avibactam and ceftolozane-tazobactam have relevant literature. Aztreonam-avibactam holds promise for the treatment of infections by metallo-β-lactamase (MBL)-producing organisms. Recently approved cefiderocol possesses an extended antibacterial spectrum, including KPC- and MBL-producers. However, recently published data have toned down optimism about treating VAP caused by carbapenem-resistant Acinetobacter baumannii. For the latter, eravacycline may provide additional hope, pending pertinent data. Non-antibiotic treatments currently being considered as adjunct therapeutic approaches are welcome. Nevertheless, they will hopefully substitute current antimicrobials in the future.

Role of microbiological tests and biomarkers in antibiotic stewardship

Laboratory tests are critical in the detection and timely treatment of infection. Two categories of tests are commonly used in neonatal sepsis management: those that identify the pathogen and those that detect host response to a potential pathogen. Decision-making around antibiotic choice is related to the performance of tests that directly identify pathogens. Advances in these tests hold the key to progress in antibiotic stewardship. Tests measuring host response, on the other hand, are an indirect marker of potential infection. While an important measure of the patient's clinical state, in the absence of pathogen detection these tests cannot confirm the appropriateness of antibiotic selection. The overall impact these tests then have on antibiotic utilization depends the test's specificity for bacterial infection, clinical scenario where it is being used and the decision-rule it is being integrated into for use. In this review we discuss common and emerging laboratory tests available for assisting management of neonatal infection and specifically focus on the role they play in optimizing antibiotic utilization.

Predicting Bacterial Versus Viral Infection, or None of the Above: Current and Future Prospects of Biomarkers

Sepsis and pneumonia cause significant morbidity and mortality worldwide. Despite improvements in diagnostic methodologies for organism identification, the early recognition and further risk stratification of these infections can be challenging. Although traditional clinical scoring systems are beneficial for the management of sepsis and pneumonia, biomarkers supporting the diagnosis and management of these infectious diseases are needed. Many biomarkers have been identified and there is no lack of studies and meta-analyses assessing the utility of biomarkers. Focusing primarily on sepsis and pneumonia, this article discusses the most commonly used biomarkers for which clinical laboratory testing methods are available.

Duration of antibiotic therapy in critically ill patients: a randomized controlled trial of a clinical and C-reactive protein-based protocol versus an evidence-based best practice strategy without biomarkers

Background

The rational use of antibiotics is one of the main strategies to limit the development of bacterial resistance. We therefore sought to evaluate the effectiveness of a C-reactive protein-based protocol in reducing antibiotic treatment time in critically ill patients.

Methods

A randomized, open-label, controlled clinical trial conducted in two intensive care units of a university hospital in Brazil. Critically ill infected adult patients were randomly allocated to (i) intervention to receive antibiotics guided by daily monitoring of CRP levels and (ii) control to receive antibiotics according to the best practices for rational use of antibiotics.

Results

One hundred thirty patients were included in the CRP (n = 64) and control (n = 66) groups. In the intention-to-treat analysis, the median duration of antibiotic therapy for the index infectious episode was 7.0 (5.0–8.8) days in the CRP and 7.0 (7.0–11.3) days in the control (p = 0.011) groups. A significant difference in the treatment time between the two groups was identified in the curve of cumulative suspension of antibiotics, with less exposure in the CRP group only for the index infection episode (p = 0.007). In the per protocol analysis, involving 59 patients in each group, the median duration of antibiotic treatment was 6.0 (5.0–8.0) days for the CRP and 7.0 (7.0–10.0) days for the control (p = 0.011) groups. There was no between-group difference regarding the total days of antibiotic exposure and antibiotic-free days.

Conclusions

Daily monitoring of CRP levels may allow early interruption of antibiotic therapy in a higher proportion of patients, without an effect on total antibiotic consumption. The clinical and microbiological relevance of this finding remains to be demonstrated.

Trial registry

ClinicalTrials.gov Identifier: NCT02987790. Registered 09 December 2016.

A proposal for a comprehensive approach to infections across the surgical pathway

Despite evidence supporting the effectiveness of best practices in infection prevention and management, many healthcare workers fail to implement them and evidence-based practices tend to be underused in routine practice. Prevention and management of infections across the surgical pathway should always focus on collaboration among all healthcare workers sharing knowledge of best practices. To clarify key issues in the prevention and management of infections across the surgical pathway, a multidisciplinary task force of experts convened in Ancona, Italy, on May 31, 2019, for a national meeting. This document represents the executive summary of the final statements approved by the expert panel.

Partial oral antibiotic therapy is non-inferior to intravenous therapy in non-critically ill patients with infective endocarditis : Review and meta-analysis

Background

Antimicrobial therapy is a cornerstone in the treatment of infective endocarditis (IE). Typically, intravenous (i.v.) therapy is given for 6 weeks or longer, leading to prolonged hospital stays and high costs. Several trials evaluating the efficacy of partial oral therapy (POT) have been published. This article aimed to review and meta-analyze studies comparing i.v. therapy versus POT in non-critically ill patients suffering from IE.

Methods

A structured database search (based on PRISMA guidelines) regarding POT versus i.v. therapy in IE was conducted using PubMed/Medline. Primary endpoint was all-cause mortality and a secondary endpoint IE relapse. Risk rates were calculated using a random effects model (DerSimonian and Laird). Heterogeneity was assessed using the I² statistics.

Results

After screening 1848 studies at title and abstract levels, 4 studies were included. A total of 765 patients suffered from primary left-sided IE, whereas right-sided IE was observed in 72 patients. Mortality rates were lower in POT versus i.v. therapy (risk ratio [RR] 0.38, 95% confidence interval, confidence interval [CI] 0.20–0.74; p = 0.004; I² 0%). IE relapse rates were similar (RR 0.63, 95% CI 0.29–1.37; p = 0.24; I² 0%).

Conclusion

Data comparing POT with standard care in IE is limited and to date only one sufficiently powered stand-alone trial exists to support its use. In this meta-analysis POT was non-inferior to i.v. therapy with respect to mortality and IE relapse in non-critically ill patients suffering from both left-sided and right-sided IE. These findings indicate that POT is a feasible treatment strategy in selected patients suffering from IE but further validation in future studies will be required.

Ventilator-Associated Pneumonia

Ventilator-associated pneumonia occurs in patients who have been intubated for at least 2–3 days with significant exposure to hospital-acquired organisms. Treatment should be initiated rapidly and cover Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, and methicillin-resistant Staphylococcus aureus(MRSA). Within 72 h or with the availability of culture results, antibiotics should be narrowed. Active research is on-going to identify patients at risk for ventilator-associated complications and to minimize the likelihood of infection in these patients.

Challenges and research priorities to progress the impact of antimicrobial stewardship

Antimicrobial stewardship programmes have been playing an important role in patient care and hospital policies. These programmes are now recognised as formal strategies for curbing the upward trend in antibiotic resistance and for improving the appropriate antimicrobial and antifungal use. The role of such programs in the era of antimicrobial resistance presents several unique challenges and opportunities, most notably in the diagnostic and therapeutic setting. Controversies remain regarding the most effective interventions and the appropriate design to evaluate their impact. In this review, based on rounds of discussion, we explain the most important challenges faced by antibiotic stewardship and antifungal stewardship programmes. We also try to suggest areas for further research.

Evaluation of INSTAND e.V.'s external quality assessment for C-reactive protein and procalcitonin

Background

The purpose of this paper was to analyze the general diagnostic strength and performance of in vitro diagnostics for C-reactive protein and procalcitonin based on the results of external quality assessment schemes (EQAs).

Methods

We analyzed qualitative and quantitative data on both markers collected by the Society for Promotion Quality Assurance in Medical Laboratories (INSTAND e.V.) from 20 EQAs. The C-reactive protein evaluation was method-specific and the procalcitonin evaluation manufacturer-specific (pseudonymized). Coefficients of variation were determined in order to evaluate interlaboratory comparability and the performance of individual laboratories during the analyzed period was examined.

Results

Overall most of our participants were able to correctly distinguish the positive from the negative samples, but we occasionally observed also false-positive results for the immunological detection of C-reactive protein. For the semi-quantitative results of C-reactive protein we observed an overall median difference below 5% except for dry chemistry methods (≤ 21%). For procalcitonin two manufacturer collectives showed a good comparability, while one manufacturer detected up to 42% higher results. The coefficients of variation are promising for both analytes even though they surpass the manufacturer’s indication for some collectives. The performance of individual laboratories during the analyzed period was more stable for C-reactive protein than for procalcitonin.

Conclusion

In-vitro diagnostic testing for C-reactive protein and procalcitonin showed promising results in our EQAs but still further improvements are needed. We recommend stepping up research on reference measurement methods for both parameters to possibly enhancing the accuracy and diagnostic strength of such assays.

Challenges and opportunities for antibiotic stewardship among preterm infants

Antibiotic stewardship programmes aim to optimise antimicrobial use to prevent the emergence of resistance species and protect patients from the side effects of unnecessary medication. The high incidence of systemic infection and associated mortality from these infections leads neonatal providers to frequently initiate antibiotic therapy and make empiric antibiotic courses one of the main contributors of antibiotic use in the neonatal units. Yet, premature infants are also at risk for acute life-threatening complications associated with antibiotic use such as necrotising enterocolitis and for long-term morbidities such as asthma. In this review, we discuss specific aspects of antibiotic use in the very low birthweight preterm infants, with a focus on empiric use, that provide opportunities for stewardship practice. We discuss strategies to risk-stratify antibiotic initiation for the risk of early-onset sepsis, optimise empiric therapy duration and antibiotic choice in late-onset sepsis, and standardise decisions for stopping empiric therapy. Lastly, review the evolving role of biomarkers in antibiotic stewardship.

Individualising Therapy to Minimize Bacterial Multidrug Resistance

The scourge of antibiotic resistance threatens modern healthcare delivery. A contributing factor to this significant issue may be antibiotic dosing, whereby standard antibiotic regimens are unable to suppress the emergence of antibiotic resistance. This article aims to review the role of pharmacokinetic and pharmacodynamic (PK/PD) measures for optimising antibiotic therapy to minimise resistance emergence. It also seeks to describe the utility of combination antibiotic therapy for suppression of resistance and summarise the role of biomarkers in individualising antibiotic therapy. Scientific journals indexed in PubMed and Web of Science were searched to identify relevant articles and summarise existing evidence. Studies suggest that optimising antibiotic dosing to attain defined PK/PD ratios may limit the emergence of resistance. A maximum aminoglycoside concentration to minimum inhibitory concentration (MIC) ratio of > 20, a fluoroquinolone area under the concentration-time curve to MIC ratio of > 285 and a β-lactam trough concentration of > 6 × MIC are likely required for resistance suppression. In vitro studies demonstrate a clear advantage for some antibiotic combinations. However, clinical evidence is limited, suggesting that the use of combination regimens should be assessed on an individual patient basis. Biomarkers, such as procalcitonin, may help to individualise and reduce the duration of antibiotic treatment, which may minimise antibiotic resistance emergence during therapy. Future studies should translate laboratory-based studies into clinical trials and validate the appropriate clinical PK/PD predictors required for resistance suppression in vivo. Other adjunct strategies, such as biomarker-guided therapy or the use of antibiotic combinations require further investigation.

How context can impact clinical trials: a multi-country qualitative case study comparison of diagnostic biomarker test interventions

Background

Context matters for the successful implementation of medical interventions, but its role remains surprisingly understudied. Against the backdrop of antimicrobial resistance, a global health priority, we investigated the introduction of a rapid diagnostic biomarker test (C-reactive protein, or CRP) to guide antibiotic prescriptions in outpatient settings and asked, “Which factors account for cross-country variations in the effectiveness of CRP biomarker test interventions?”

Methods

We conducted a cross-case comparison of CRP point-of-care test trials across Yangon (Myanmar), Chiang Rai (Thailand), and Hanoi (Vietnam). Cross-sectional qualitative data were originally collected as part of each clinical trial to broaden their evidence base and help explain their respective results. We synthesised these data and developed a large qualitative data set comprising 130 interview and focus group participants (healthcare workers and patients) and nearly one million words worth of transcripts and interview notes. Inductive thematic analysis was used to identify contextual factors and compare them across the three case studies. As clinical trial outcomes, we considered patients’ and healthcare workers’ adherence to the biomarker test results, and patient exclusion to gauge the potential “impact” of CRP point-of-care testing on the population level.

Results

We identified three principal domains of contextual influences on intervention effectiveness. First, perceived risks from infectious diseases influenced the adherence of the clinical users (nurses, doctors). Second, the health system context related to all three intervention outcomes (via the health policy and antibiotic policy environment, and via health system structures and the ensuing utilisation patterns). Third, the demand-side context influenced the patient adherence to CRP point-of-care tests and exclusion from the intervention through variations in local healthcare-seeking behaviours, popular conceptions of illness and medicine, and the resulting utilisation of the health system.

Conclusions

Our study underscored the importance of contextual variation for the interpretation of clinical trial findings. Further research should investigate the range and magnitude of contextual effects on trial outcomes through meta-analyses of large sets of clinical trials. For this to be possible, clinical trials should collect qualitative and quantitative contextual information for instance on their disease, health system, and demand-side environment.

Trial registration

ClinicalTrials.gov, NCT02758821 registered on 3 May 2016 and NCT01918579 registered on 7 August 2013.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3215-9) contains supplementary material, which is available to authorized users.

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

INTRODUCTION

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

The current status of biomarkers for the diagnosis of nosocomial pneumonias

PURPOSE OF REVIEW

Nosocomial pneumonia is a frequent and severe nosocomial infection divided in two distinct groups: hospital-acquired pneumonia and ventilator-associated pneumonia (VAP). In this context, the VAP is notoriously difficult to diagnose clinically, resulting from the lack of a 'gold standard' method of diagnosis.

RECENT FINDINGS

The use of biomarkers may potentially improve the early diagnosis of infections allowing earlier and better identification and treatment. An exhausting list of biomarkers has been studied and although far from perfect, procalcitonin (PCT) and C-reactive protein (CRP) are the most studied biomarkers used in clinical practice. Data coming from literature suggests the use of PCT for VAP prognosis and as a based algorithm tool for the reduction of duration of pneumonia therapy, as well as, the use of the CRP dynamics to the early prediction of VAP and the response to the antibiotics.

SUMMARY

The evidence for the use of biomarkers to diagnose nosocomial pneumonia as a stand-alone tool is low to moderate. Improved performance for both PCT and CRP can be obtained by using them in association with clinical features or scoring systems but prospective studies are still needed to validate this hypothesis.

Feasibility of Antimicrobial Stewardship (AMS) in Critical Care Settings: A Multidisciplinary Approach Strategy

Antimicrobial resistance is escalating and triggers clinical decision-making challenges when treating infections in patients admitted to intensive care units (ICU). Antimicrobial stewardship (AMS) may help combat this problem, but it can be difficult to implement in critical care settings. The implementation of multidisciplinary AMS in ICUs could be more challenging than what is currently suggested in the literature. Our main goal was to analyze the reduction in duration of treatment (DOT) for the most commonly used antibacterial and antifungal agents during the first six months of 2014, and during the same period two years later (2016). A total of 426 and 424 patient encounters, respectively, were documented and collected from the intensive care unit's electronic patient record system. Daily multidisciplinary ward rounds were conducted for approximately 30⁻40 min, with the goal of optimizing antimicrobial therapy in order to analyze the feasibility of implementing AMS. The only antimicrobial agent which showed a significant reduction in the number of prescriptions and in the duration of treatment during the second audit was vancomycin, while linezolid showed an increase in the number of prescriptions with no significant prolongation of the duration of treatment. A trend of reduction was also seen in the DOT for co-amoxiclavulanate and in the number of prescriptions of anidulafungin without any corresponding increases being observed for other broad-spectrum anti-infective agents (p-values of 0.07 and 0.05, respectively).

The GISA call to action for the appropriate use of antimicrobials and the control of antimicrobial resistance in Italy

The spread of antibiotic resistance is one of the leading public health problems in Italy. A European Centre for Disease Prevention and Control country visit recently confirmed the major challenges and made important suggestions. In response, the Ministry of Health published the National Plan for Antimicrobial Resistance Containment, and a group of experts belonging to the Italian Group of Antimicrobial Stewardship (GISA) convened to develop a summary of practical recommendations. The GISA document is intended for use by practising physicians; it aims to increase the rational use of antimicrobials in the treatment of infections, and to change the culture of infection control of antibiotic-resistant bacteria, through the translation of theoretical knowledge into priority actions. This document has been endorsed by several national scientific societies, and reflects the particular challenges that are faced in Italy. Nevertheless, it is considered that the general principles and approaches discussed are relevant, particularly to other developed economies.

Summary of the international clinical guidelines for the management of hospital-acquired and ventilator-acquired pneumonia

A summary of the evidence and recommendations made in the ERS/ESICM/ESCMID/ALAT guidelines for the management of hospital-acquired pneumonia and ventilator-associated pneumonia http://ow.ly/S3zA30iZfLa.

The social role of C-reactive protein point-of-care testing to guide antibiotic prescription in Northern Thailand

New and affordable point-of-care testing (POCT) solutions are hoped to guide antibiotic prescription and to help limit antimicrobial resistance (AMR)—especially in low- and middle-income countries where resource constraints often prevent extensive diagnostic testing. Anthropological and sociological research has illuminated the role and impact of rapid point-of-care malaria testing. This paper expands our knowledge about the social implications of non-malarial POCT, using the case study of a C-reactive-protein point-of-care testing (CRP POCT) clinical trial with febrile patients at primary-care-level health centres in Chiang Rai province, northern Thailand. We investigate the social role of CRP POCT through its interactions with (a) the healthcare workers who use it, (b) the patients whose routine care is affected by the test, and (c) the existing patient-health system linkages that might resonate or interfere with CRP POCT. We conduct a thematic analysis of data from 58 purposively sampled pre- and post-intervention patients and healthcare workers in August 2016 and May 2017.

We find widespread positive attitudes towards the test among patients and healthcare workers. Patients’ views are influenced by an understanding of CRP POCT as a comprehensive blood test that provides specific diagnosis and that corresponds to notions of good care. Healthcare workers use the test to support their negotiations with patients but also to legitimise ethical decisions in an increasingly restrictive antibiotic policy environment. We hypothesise that CRP POCT could entail greater patient adherence to recommended antibiotic treatment, but it could also encourage riskier health behaviour and entail potentially adverse equity implications for patients across generations and socioeconomic strata. Our empirical findings inform the clinical literature on increasingly propagated point-of-care biomarker tests to guide antibiotic prescriptions, and we contribute to the anthropological and sociological literature through a novel conceptualisation of the patient-health system interface as an activity space into which biomarker testing is introduced.

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Novel social research contribution to the study of antimicrobial resistance.

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Examines increasingly popular diagnostic point-of-care testing (POCT).

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Analyses POCT introduction at the patient – health system interface.

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Reveals interferences of test with patient and health worker behaviour.

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Provides evidence of un-/intended behavioural effects of point-of-care tests.

The usefulness of appetite and energy intake-based algorithms to assess treatment effect of a bacterial infection: An observational prospective study

BACKGROUND

The diagnosis of infectious diseases and the duration of antibiotic therapies are generally based on empirical rules. Studies implicate that the use biological markers can be used as a reliable method to shorten antibiotic therapies. The return of appetite is a clinical aspect of recovery from an infection that may be used to guide antibiotic therapies.

OBJECTIVE

To compare changes in appetite and daily energy intake with changes in CRP-levels in patients recovering from an infection.

DESIGN

Observational study using a consecutive sample of patients admitted to the unit for infectious diseases at a University Hospital in Sweden, February to April 2014. Energy intake, CRP-levels and appetite were recorded daily. Energy intake was calculated using estimated energy contents. Appetite was measured using a validated visual analogue scale. Changes in daily energy intakes, CRP-levels and appetite were analysed.

RESULTS

49 patients (51% men) were included in the analysis from the overall population of 256 patients. During the length of the stay (median 3 days) CRP-levels fell in 92% of the patients (p<0.001), daily energy intake increased in 73% (median intake +6381 kJ/day, p<0.001) and appetite increased in 55% of the patients (p = 0.181). VAS-estimations of appetite augmented in 55%, decreased in 41% and were equal in 5% of the patients (p = 0.181). There was a non-significant difference in the within-subject variances in daily energy intake between female and male patients but not in other subsets.

CONCLUSIONS

We found a significantly increase in the daily energy intake but not in self-estimated appetite in patients recovering from an infection. We suggest measuring the daily energy intake as a complement to other biological and clinical markers among inpatients to assess treatment effect.