The clinical role of procalcitonin in hematopoietic SCT

The Clinical Value of Procalcitonin in the Neutropenic Period After Allogeneic Hematopoietic Stem Cell Transplantation

The diagnostic value of procalcitonin and the prognostic role of PCT clearance remain unclear in neutropenic period after allogeneic hematopoietic stem cell transplantation introduction. This study evaluated 219 febrile neutropenic patients (116, retrospectively; 103, prospectively) who underwent allo-HSCT from April 2014 to March 2016. The area under the receiver operator characteristic curve (AUC) of PCT for detecting documented infection (DI) was 0.637, and that of bloodstream infection (BSI) was 0.811. In multivariate analysis, the inability to decrease PCT by more than 80% within 5–7 days after the onset of fever independently predicted poor 100-day survival following allo-HSCT (P = 0.036). Furthermore, the prognostic nomogram combining PCTc and clinical parameters showed a stable predictive performance, supported by the C-index of 0.808 and AUC of 0.813 in the primary cohort, and C-index of 0.691 and AUC of 0.697 in the validation cohort. This study demonstrated the diagnostic role of PCT in documented and bloodstream infection during the neutropenic period after allo-HSCT. PCTc might serve as a predictive indicator of post-HSCT 100-day mortality. A nomogram based on PCTc and several clinical factors effectively predicted the 100-day survival of febrile patients and may help physicians identify high-risk patients in the post-HSCT neutropenic period.

Serum procalcitonin as an independent diagnostic markers of bacteremia in febrile patients with hematologic malignancies

Background

Serum procalcitonin (PCT) and C-reactive protein (CRP) are biomarkers of infection. In patients with hematologic disorders with or without hematopoietic stem cell transplantation (HSCT), it is difficult to distinguish bloodstream infections from aseptic causes of febrile episodes. The objective of this study was to investigate diagnostic values of PCT and CRP in predicting systemic bacterial infection in patients with hematologic malignancies.

Methods

Clinical and laboratory data of 614 febrile episode cases from 511 patients were analyzed. Febrile episodes were classified into four groups: (1) culture-positive bacterial infection by Gram-positive cocci (GPC), (2) culture-positive bacterial infection by Gram-negative bacilli (GNB), (3) fungal infection, and (4) viral infection or a noninfectious etiology.

Results

Of 614 febrile cases, systemic bacterial infections were confirmed in 99 (16.1%) febrile episodes, including 38 (6.2%) GPC and 61 (9.9%) GNB infections. PCT levels were significantly higher in GNB infectious episodes than those in febrile episodes caused by fungal infection (0.58 ng/mL (95% CI: 0.26–1.61) vs. 0.22 ng/mL (0.16–0.38), P = 0.047). Bacterial infectious episodes showed higher PCT and CRP levels than non-bacterial events (PCT: 0.49 (0.26–0.93) ng/mL vs. 0.20 (0.18–0.22) ng/mL, P < 0.001; CRP: 76.6 (50.5–92.8) mg/L vs. 58.0 (51.1–66.5) mg/L, P = 0.036). For non-neutropenic febrile episodes, both PCT and CRP discriminated bacteremia from non-bacteremia. However, in neutropenic febrile episodes, PCT only distinguished bacteremia from non-bacteremia. In non-neutropenic episode, both PCT and CRP showed good diagnostic accuracy (AUC: 0.757 vs. 0.763). In febrile neutropenia, only PCT discriminated bacteremia from non-bacterial infection (AUC: 0.624) whereas CRP could not detect bacteremia (AUC: 0.500, 95% CI: 0.439–0.561, P > 0.05).

Conclusions

In this single-center observational study, PCT was more valuable than CRP for discriminating between bacteremia and non-bacteremia independent of neutropenia or HSCT.

Inpatient Antibiotic Stewardship Interventions in the Adult Oncology and Hematopoietic Stem Cell Transplant Population: A Review of the Literature

Objective: To review the use of antibiotic stewardship interventions in the adult oncology and hematopoietic cell transplantation (HCT) populations. Data Sources: A literature search of PubMed was performed from inception to October 31, 2019. The general search terms used were oncology, cancer, hematologic malignancy, antimicrobial stewardship, antibiotic stewardship, febrile neutropenia, neutropenic fever, de-escalation, discontinuation, prophylaxis, practice guidelines, clinical pathway, rapid diagnostics, Filmarray, Verigene, MALDI-TOF, antibiotic allergy, and antimicrobial resistance. Study Selection and Data Extraction: Relevant English-language studies describing interventions supported by the Infectious Diseases Society of America guidelines on "Implementing an Antibiotic Stewardship Program" were included. Data Synthesis: Antibiotic stewardship publications in the oncology population have increased in recent years. Studies have described the impact of stewardship interventions, including preauthorization, prospective audit and feedback, implementation of clinical pathways, de-escalation of empirical antibiotics for febrile neutropenia (FN) prior to neutrophil recovery, allergy assessments, and use of rapid diagnostic testing. Many of these interventions have been shown to decrease antibiotic use without increased negative consequences, such as affecting length of stay or mortality. Relevance to Patient Care and Clinical Practice: This review synthesizes available evidence for implementing antibiotic stewardship interventions, particularly de-escalation of antibiotics for FN and implementation of clinical pathways for FN and sepsis, in oncology patients and HCT recipients. Summary tables highlight studies and specific research needs for clinicians. Conclusions: Immunocompromised populations, including oncology patients, have often been excluded from stewardship studies. Antibiotic stewardship is effective in reducing antibiotic consumption and improving outcomes in this patient population, although more quality data are needed.

Comparison of procalcitonin and C-reactive protein as early diagnostic marker for the identification of transplant-related adverse events after allogeneic hematopoietic stem cell transplantation in pediatric patients

PURPOSE

To evaluate serum procalcitonin (PCT) and C-reactive protein (CRP) as diagnostic biomarkers of transplant-related adverse events (TRAE) in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT).

METHODS

This study analyzed PCT and CRP levels of 214 pediatric patients with a median age of 8.5 years (0.4-17.8 years) undergoing allogeneic HSCT with respect to major TRAE.

RESULTS

26 patients (12.1%) did not experience TRAE (control group), and 188 (87.9%) experienced median 2 (range 1-4) TRAE. Median CRP and PCT were highly and significantly increased during sepsis/SIRS and bacteremia (17.24 mg/dl | 6.30 ng/ml; p < 0.0001 vs. prior values), graft rejection (14.73 mg/dl | 3.20 ng/ml; p < 0.0001), and liver GvHD (6.88 mg/dl | 2.29 ng/ml; p < 0.01). Strong CRP increases and slight/minimal/no PCT increases occurred during fungemia (8.85 mg/dl | 0.72 ng/ml; p < 0.001), intestinal GvHD (8.73 mg/dl | 1.06 ng/ml; p < 0.0001), VOD (10.84 mg/dl | 0.59 ng/ml; p < 0.01), mucositis (8.84 mg/dl | 0.81 ng/ml; p < 0.0001), and viremia (3.62 mg/dl; p < 0.0001 | 0.43 ng/ml; below normal limit). During skin GvHD, CRP and PCT were slightly increased (2.03 mg/dl | 0.93 ng/ml; p < 0.0001).

CONCLUSIONS

CRP and PCT did not show congruent changes during TRAE. PCT was a clinically relevant marker for the early detection and differentiation of severe mucositis and sepsis/SIRS and bacteremia during the critical neutropenic period after HSCT. PCT helped to discriminate acute intestinal GvHD from adenovirus viremia and liver GvHD from hepatic VOD. Thus, PCT may be a valuable parameter to enable a prompt and appropriate treatment during these complications, improving patient outcomes.

Comparison of the Power of Procalcitonin and C-Reactive Protein to Discriminate between Different Aetiologies of Fever in Prolonged Profound Neutropenia: A Single-Centre Prospective Observational Study

Management of fever in prolonged, profound neutropenia remains challenging with many possible infectious and non-infectious causes. We investigated whether procalcitonin (PCT) is superior to C-reactive protein (CRP) in discriminating between different aetiologies of fever in this setting.

CRP and PCT were tested daily during 93 neutropenic episodes in 66 patients. During this study period, 121 febrile episodes occurred and were classified into four categories based on clinical and microbiological findings: microbiologically documented infection (MDI); clinically documented infection (CDI); proven or probable invasive fungal disease (IFD); fever of unknown origin (FUO). Values of PCT and CRP at fever onset as well as two days later were considered for analysis of their performance in distinguishing aetiologies of fever.

At fever onset, no significant difference in PCT values was observed between different aetiologies of fever, whereas median CRP values were significantly higher in case of IFD (median 98.8 mg/L vs 28.8 mg/L, p=0.027). Both PCT and CRP reached their peak at a median of 2 days after fever onset. Median PCT values on day 2 showed no significant difference between the aetiologies of fever. Median CRP values on day 2 were significantly higher in IFD (median 172 mg/L versus 78.4 mg/L, p=0.002). In MDI median CRP values rose > 100 mg/L, whereas they did not in CDI or FUO.

PCT has no added value over CRP for clinical management of fever in prolonged, profound neutropenia. When performing reassessment 2 days after fever onset, CRP has better discriminatory power between aetiologies of fever.

Diagnostic Evaluation of Pulmonary Abnormalities in Patients with Hematologic Malignancies and Hematopoietic Cell Transplantation

Pulmonary complications (PC) of hematologic malignancies and their treatments are common causes of morbidity and mortality. Early diagnosis is challenging due to host risk factors, clinical instability, and provider preference. Delayed diagnosis impairs targeted treatment and may contribute to poor outcomes. An integrated understanding of clinical risk and radiographic patterns informs a timely approach to diagnosis and treatment. There is little prospective evidence guiding optimal modality and timing of minimally invasive lung sampling; however, a low threshold for diagnostic bronchoscopy during the first 24 to 72 hours after presentation should be a guiding principle in high-risk patients.

Accuracy of C - Reactive protein as a bacterial infection marker in critically immunosuppressed patients: A systematic review and meta-analysis

BACKGROUND

There is a need for a better understanding of the role of C-reactive protein (CRP) as a valid marker for the detection of bacterial infections in critically immunosuppressed patients. A high negative predictive value of CRP is also needed to rule out sepsis and bacterial infections in immunocompetent patients. However, few studies have evaluated the performance of CRP in immunocompromised hosts. The aim of the present study was to evaluate the performance of CRP as a marker of infection in critically immunosuppressed patients.

METHODS

The inclusion criterion was immunosuppression for which CRP was used as a bacterial infection marker. Searches were performed in the Cochrane Register, MEDLINE, EMBASE, SCOPUS, Web OF Science, LILACS and CINAHL databases. We applied the Quality Assessment of Diagnostic Accuracy Studies tool 2 (QUADAS 2) to evaluate the quality of the articles and evaluated the test accuracy parameters using hierarchical summary receiver operating characteristic (HSROC) curves and bivariate random effect models.

RESULTS

Only 13 of 21 studies produced quantitative results. We analyzed all studies using the random effects method (restricted maximum likelihood) and obtained a joint diagnostic odds ratio (DOR) of 3.04 (95% confidence interval [CI] 1.71-5.40) with heterogeneity (I²=91%, Q=181.48, p<0.001). Therefore, a bivariate model was applied. Analyzing the tuberculosis carrier, steroid user, or presence of opportunistic infection subgroups, as described in the proposal, was not possible due to the lack of information on these topics included in the articles.

CONCLUSIONS

CRP appears to be a good screening tool for sepsis in critically immunosuppressed patients. Submitted PROSPERO 2015: CRD42015019329.

Current use and potential role of procalcitonin in the diagnostic work up and follow up of febrile neutropenia in hematological patients

INTRODUCTION

Febrile neutropenia (FN) represents a life-threatening complication in hematological malignancies. Its etiology is most often due to infections even though FN of other origins, such as tumor-related fever and non-infectious inflammation, should rapidly be ruled out. Initially, C-reactive protein and, more recently, procalcitonin (PCT) have been proposed as useful biomarkers for differential diagnosis. PCT was shown to be a good biomarker of bacterial infections and their clinical outcomes. Definition of standard cut-offs and design of PCT-guided treatment protocols remain however to be defined. Areas covered: In this review, highlights on the current clinical use of PCT and its potential role as a diagnostic tool have been discussed by a panel of physicians from different areas of expertise. We provide current clinical evidence that PCT has been shown to be a reliable biomarker to differentiate fever of bacterial origin from other causes. Moreover, the Authors convened to a round-table to discuss their 'real-life experience' and offer their recommendations by a Delphi survey. Expert commentary: PCT has an important clinical role in FN. Issues such as the validation of a specific decision algorithm that includes PCT to monitor antibiotic choice and treatment duration will be addressed in prospective studies.

Diagnostic performance of procalcitonin, presepsin, and C-reactive protein in patients with hematological malignancies

INTRODUCTION

Infections represent a major complication of hematological malignancies. C-reactive protein (CRP) and procalcitonin (PCT) have been used as diagnostic biomarkers of infections, but do not produce definitive findings. Recently, a new biomarker, presepsin, has been used as a diagnostic tool for detecting infections in the fields of emergency and neonatal medicine. However, the usefulness of presepsin for identifying infections in patients with hematological malignancies, including those who develop febrile neutropenia, remains unclear.

METHODS

In this study, we retrospectively analyzed the utility of PCT, presepsin, and CRP as biomarkers of infections during 49 febrile episodes that occurred in 28 patients with hematological malignancies.

RESULTS

The levels of PCT, but not those of CRP or presepsin, were significantly higher in the infection group than in the uninfected group (P<.03), indicating that PCT might be a more sensitive biomarker of infections. No differences in presepsin levels were detected between the patients with and without neutropenia, or between the infected and uninfected patients with neutropenia, indicating that presepsin might have less diagnostic value in patients with neutropenia.

CONCLUSIONS

We conclude that PCT might provide additional information and could be used in combination with other biomarkers to detect infections in patients with hematological malignancies.

The clinical value of biomarkers in respiratory complications in hematopoietic SCT

To determine the role of biomarkers in the clinical management of respiratory complications (RC) in hematopoietic stem cell transplantation (HSCT) recipients, we have prospectively evaluated a cohort of 175 patients followed-up for 1 year after HSCT. To avoid misinterpretation, we have excluded both unidentified respiratory infections (RI) and mixed RI. A total of 64 RC were included. Plasma levels of C-reactive protein (CRP), procalcitonin (PCT) and proadrenomedullin (proADM) were measured at diagnosis and on day 3 and 7. Different cytokines were evaluated in serum on the first day. No HSCT recipients without RC were included as a control group. Compared with RI, non-infectious RC showed a significant increase in CRP, proADM and interleukin 6 on day 0 (P=0.005; P=0.03 and P=0.04, respectively). When only RI were considered, we observed that bacterial–fungal PI showed higher levels of CRP (P=0.02), PCT (P=0.04) and proADM (P<0.01). Persistent low levels of proADM biomarkers suggest viral infection (specificity and positive predictive value 100%). Patients dying of RC had PCT and proADM levels higher than survivors (P=0.002 and P=0.03, respectively). In HSCT recipients biomarkers increase in both infectious and non-infectious RC. They may have utility in the assessment of the severity of RC and in suspecting a viral etiology.

Host Biomarkers for Distinguishing Bacterial from Non-Bacterial Causes of Acute Febrile Illness: A Comprehensive Review

Background

In resource limited settings acute febrile illnesses are often treated empirically due to a lack of reliable, rapid point-of-care diagnostics. This contributes to the indiscriminate use of antimicrobial drugs and poor treatment outcomes. The aim of this comprehensive review was to summarize the diagnostic performance of host biomarkers capable of differentiating bacterial from non-bacterial infections to guide the use of antibiotics.

Methods

Online databases of published literature were searched from January 2010 through April 2015. English language studies that evaluated the performance of one or more host biomarker in differentiating bacterial from non-bacterial infection in patients were included. Key information extracted included author information, study methods, population, pathogens, clinical information, and biomarker performance data. Study quality was assessed using a combination of validated criteria from the QUADAS and Lijmer checklists. Biomarkers were categorized as hematologic factors, inflammatory molecules, cytokines, cell surface or metabolic markers, other host biomarkers, host transcripts, clinical biometrics, and combinations of markers.

Findings

Of the 193 citations identified, 59 studies that evaluated over 112 host biomarkers were selected. Most studies involved patient populations from high-income countries, while 19% involved populations from low- and middle-income countries. The most frequently evaluated host biomarkers were C-reactive protein (61%), white blood cell count (44%) and procalcitonin (34%). Study quality scores ranged from 23.1% to 92.3%. There were 9 high performance host biomarkers or combinations, with sensitivity and specificity of ≥85% or either sensitivity or specificity was reported to be 100%. Five host biomarkers were considered weak markers as they lacked statistically significant performance in discriminating between bacterial and non-bacterial infections.

Discussion

This manuscript provides a summary of host biomarkers to differentiate bacterial from non-bacterial infections in patients with acute febrile illness. Findings provide a basis for prioritizing efforts for further research, assay development and eventual commercialization of rapid point-of-care tests to guide use of antimicrobials. This review also highlights gaps in current knowledge that should be addressed to further improve management of febrile patients.

Risk factor for death in hematopoietic stem cell transplantation: are biomarkers useful to foresee the prognosis in this population of patients?

BACKGROUND

The morbidity and mortality in hematopoietic stem cell transplantation (HSCT) occur due to infectious complications and constitute the major clinical problems in HSCT recipients. The role of the use of biomarkers in post-HSCT patients is still controversial.

OBJECTIVES

To assess the serum values of biomarkers interleukin 6 (IL-6), procalcitonin (PCT) and C-reactive protein (CRP) and risk factors for post-HSCT death.

PATIENTS AND METHODS

Prospective study conducted in patients submitted to HSCT at a university hospital. Biomarkers (IL-6, PCT and CRP) were assessed on the day afebrile neutropenia was detected, in the febrile event, 24 and 72 h after fever onset and 48 h or 5 days if fever persisted. Patients were compared as to the death outcome within 30 days from the HSCT. Variables with p < 0.15 were included in the multivariate analysis model (MVA) that were performed for all patients included in the study and separated for autologous and allogeneic HSCT patients.

RESULTS

296 patients with ages ranging between 15 and 70 years, neutropenic, submitted to HSCT, being 216 (73%) autologous and 80 (20%) allogeneic were assessed. One hundred and ninety (64.2%) patients presented fever after the transplantation and infection microbiologically controlled in 78 (26.4%). Twenty-three cases (7.8%) evolved to death. The risk factors associated with death in the bivariate analysis were age, allogeneic transplantation, unrelated transplantation, GVHD, bloodstream infection by Gram-negative, IL-6 >140 pg/mL and CRP ≥ 120 mg/L and the protective ones were lymphoma and hospital outpatient support. The independent variables in the MVA associated with death were allogeneic and unrelated transplantation, blood stream infection (BSI) by Gram-negative, LDH ≥ 390 UI/L, urea ≥ 25 mg/dL and CRP ≥ 120 mg/L for HSCT transplanted patients and BSI due to Gram-negative and CRP ≥ 120 mg/L for allogeneic HSCT, however, CRP ≥ 120 mg/L did not remain in the model when urea ≥ 25 mg/L was included. No independent risk factor was found for autologous patients.

CONCLUSIONS

Out of the biomarkers assessed, only CRP ≥ 120 mg/L was independently associated with death. Other risk factors found were: type of transplantation (allogeneic and unrelated), bloodstream infection by Gram-negative, LDH ≥ 390 UI/L and urea ≥ 25 mg/dL. For allogeneic patients only CRP ≥ 120 mg/L and BSI due to Gram-negative were risk factors for death; however, CRP did not remain in the model when urea ≥ 25 mg/L was included.

Triggers for driving treatment of at-risk patients with invasive fungal disease

Timing of treatment for invasive fungal disease (IFD) is critical for making appropriate clinical decisions. Historically, many centres have treated at-risk patients prior to disease detection to try to prevent fungal colonization or in response to antibiotic-resistant fever. Many studies have indicated that a diagnostic-driven approach, using radiological tests and biomarkers to guide treatment decisions, may be a more clinically relevant and cost-effective approach. The Invasive Fungal Infections Cooperative Group of the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) defined host clinical and mycological criteria for proven, probable and possible classes of IFD, to aid diagnosis. However, some patients at risk of IFD do not meet EORTC/MSG criteria and have been termed Groups B (patients with persistent unexplained febrile neutropenia) and C (patients with non-definitive signs of IFD) in a study by Maertens et al. (Haematologica 2012; 97: 325-7). Consequently, we considered the most appropriate triggers (clinical or radiological signs or biomarkers) for treatment of all patient groups, especially the unclassified B and C groups, based on our clinical experience. For Group C patients, additional diagnostic testing is recommended before a decision to treat, including repeat galactomannan tests, radiological scans and analysis of bronchoalveolar lavage fluid. Triggers for stopping antifungal treatment were considered to include resolution of all clinical signs and symptoms. For Group B patients, it was concluded that better definition of risk factors predisposing patients to fungal infection and the use of more sensitive diagnostic tests are required to aid treatment decisions and improve clinical outcomes.

Elevation of CRP precedes clinical suspicion of bloodstream infections in patients undergoing hematopoietic cell transplantation

OBJECTIVES

We aimed to examine whether C-reactive protein (CRP) elevation precedes the clinical signs and symptoms of infection among patients undergoing allogeneic hematopoietic cell transplantation (HCT).

METHODS

Prospective cohort of patients undergoing allogeneic HCT in whom daily blood samples for CRP were taken. In a nested case-control study, cases were defined as patients with clinically-significant bloodstream infection (BSI). Controls were defined as afebrile patients without infection, matched by age, time after transplantation and GVHD status. We calculated the mean difference (MD) between CRP 1 day before clinical suspicion of infection (day -1) and days -2 and -3 (deltaM1M2 and delta M1M3, respectively) and compared cases vs. controls.

RESULTS

From January 2010 to April 2012 we identified 46 cases of BSIs. The difference between the mean delta M1M3 and delta M1M2 in cases and controls were significantly higher in patients with BSI compared to controls (MD = 5.9, 95% CI 3.5-8.3, p < .001 and MD = 4.2 mg/dl, 95% CI 2.2-6.2, p < .001, respectively). In the overall cohort, sensitivity, specificity, positive and negative predictive values of a daily delta value >4 mg/dl were 52%, 98%, 66% and 98%, respectively.

CONCLUSIONS

A daily increase of CRP blood levels of >4 mg/dl in afebrile HCT recipients should trigger an evaluation for infection.

Prediction of transplant-related complications by C-reactive protein levels before hematopoietic SCT

Various biomarkers have been investigated with regard to their ability to predict the outcome of allogeneic hematopoietic SCT (HSCT). In this study, we retrospectively reviewed 90 recipients who received HSCT between 2007 and 2011 in our institution, and evaluated the predictive value of the baseline serum C-reactive protein (CRP) levels just before the initiation of conditioning for transplant-related complications after allogeneic HSCT. A receiver-operating characteristic curve revealed that the baseline serum CRP levels had an excellent predictive value for non-relapse mortality (NRM), with an area under the curve of 0.83. The sensitivity and specificity for NRM were 80% and 87%, respectively, with a cutoff of 0.6 mg/dL. With this cutoff value, multivariate analyses revealed that a higher baseline CRP level was an independent risk factor for NRM (HR 6.21, P<0.01), grade III-IV acute GVHD (HR 3.91, P=0.03) and poor overall survival (HR 3.27, P=0.0018). On the other hand, the baseline CRP level did not predict infectious events. These findings suggested that CRP levels before conditioning may be a useful predictive biomarker for poor survival.