Procalcitonin as a marker of sepsis and outcome in patients with neurotrauma: an observation study

Development and application of a risk nomogram for the prediction of risk of carbapenem-resistant Acinetobacter baumannii infections in neuro-intensive care unit: a mixed method study

OBJECTIVE

This study aimed to develop and apply a nomogram with good accuracy to predict the risk of CRAB infections in neuro-critically ill patients. In addition, the difficulties and expectations of application such a tool in clinical practice was investigated.

METHODS

A mixed methods sequential explanatory study design was utilized. We first conducted a retrospective study to identify the risk factors for the development of CRAB infections in neuro-critically ill patients; and further develop and validate a nomogram predictive model. Then, based on the developed predictive tool, medical staff in the neuro-ICU were received an in-depth interview to investigate their opinions and barriers in using the prediction tool during clinical practice. The model development and validation is carried out by R. The transcripts of the interviews were analyzed by Maxqda.

RESULTS

In our cohort, the occurrence of CRAB infections was 8.63% (47/544). Multivariate regression analysis showed that the length of neuro-ICU stay, male, diabetes, low red blood cell (RBC) count, high levels of procalcitonin (PCT), and number of antibiotics ≥ 2 were independent risk factors for CRAB infections in neuro-ICU patients. Our nomogram model demonstrated a good calibration and discrimination in both training and validation sets, with AUC values of 0.816 and 0.875. Additionally, the model demonstrated good clinical utility. The significant barriers identified in the interview include "skepticism about the accuracy of the model", "delay in early prediction by the indicator of length of neuro-ICU stay", and "lack of a proper protocol for clinical application".

CONCLUSIONS

We established and validated a nomogram incorporating six easily accessed indicators during clinical practice (the length of neuro-ICU stay, male, diabetes, RBC, PCT level, and the number of antibiotics used) to predict the risk of CRAB infections in neuro-ICU patients. Medical staff are generally interested in using the tool to predict the risk of CRAB, however delivering clinical prediction tools in routine clinical practice remains challenging.

Procalcitonin and Pediatric Traumatic Brain Injury: Differentiating Neuro-Storming From Infection

INTRODUCTION

Recurrent febrile episodes represent a diagnostic challenge in the pediatric traumatic brain injury (TBI) population as they may indicate presence of infection versus sterile neuro-storming. Procalcitonin (PCT) is a promising biomarker used in pediatric sepsis; however, data are limited regarding use in TBI. We hypothesized PCT helps discern neuro-storming from sepsis in children with TBI.

MATERIALS AND METHODS

A single-institution retrospective review (2014-2021) identified pediatric patients (aged 0-18 y) with moderate-to-severe TBI and intensive care unit admission > 2 d. Patients with multiple febrile events who underwent infectious evaluation including cultures and PCT drawn within 48 h of fever were included. Demographics, vital signs, infectious biomarkers including PCT, and culture data were captured. Univariate and multivariate analyses were performed to determine variables associated with culture positive status.

RESULTS

One hundred and fifty six patients were admitted to the intensive care unit with moderate-to-severe TBI during the study period. Eighty five patients (54%) experienced recurrent febrile episodes. Twenty four (28%) met inclusion criteria, undergoing 32 total infectious workups. Twenty one workups were culture-positive (66%) in a total of 18 patients. Median PCT levels were not statistically different between culture-positive and culture-negative workups (P = 0.94). In multivariate modeling, neither PCT [odds ratio 0.89 (confidence interval: 0.75-1.05)] nor temperature [odds ratio 7.34 (confidence interval: 0.95-57.16)] correlated with positive bacterial cultures.

CONCLUSIONS

In this small pilot analysis, recurrent febrile episodes were common and PCT did not correlate with sepsis or neuro-storming in pediatric TBI patients. Prospective protocols are needed to better understand the utility of PCT and identify predictors of bacterial infection to improve early diagnosis of sepsis in this population.

Prognostic Value of Serum Procalcitonin Based Model in Moderate to Severe Traumatic Brain Injury Patients

Objective

Procalcitonin (PCT) is an acknowledged marker of systemic inflammatory response. Previous studies have not reached agreement on the association between serum PCT and outcome of traumatic brain injury (TBI) patients. We designed this study to confirm the prognostic value of PCT in isolated TBI and those with extracranial injury, respectively.

Methods

Patients hospitalized in our hospital for moderate-to-severe TBI between March 2015 and December 2019 were included. Logistic regression analysis was performed to validate the association between PCT and in-hospital mortality in these patients. AUC (area under the receiver operating characteristics curve) of PCT and constructed model were calculated and compared.

Results

Among the included 211 patients, 81 patients suffered a poor outcome, with a mortality rate of 38.4%. Non-survivors had a higher level of serum PCT (2.73 vs 0.72, p<0.001) and lower GCS (5 vs 7, p<0.001) on admission than survivors. AUC of single PCT for predicting mortality in isolated TBI and those with extracranial injury were 0.767 and 0.553, respectively. Multivariate logistic regression showed that GCS (OR=0.744, p=0.008), glucose (OR=1.236, p<0.001), cholesterol (OR=0.526, p=0.002), and PCT (OR=1.107, p=0.022) were independently associated with mortality of isolated TBI. The AUC of the prognostic model composed of GCS, glucose, cholesterol, and PCT was 0.868 in isolated TBI.

Conclusion

PCT is an efficient marker of outcome in isolated moderate-to-severe TBI but not those with extracranial injury. A prognostic model incorporating PCT is useful for clinicians to make early risk stratification for isolated TBI.

Inflammation and the role of infection: Complications and treatment options following neurotrauma

Traumatic brain injury can have devastating consequences for patients and extended hospital stays and recovery course. Recent data indicate that the initial insult causes profound changes to the immune system and leads to a pro-inflammatory state. This alteration in homeostasis predisposes patients to an increased risk of infection and underlying autoimmune conditions. Increased emphasis has been placed on understanding this process both in the clinical and preclinical literature. This review highlights the intrinsic inflammatory conditions that can occur within the initial hospital stay, discusses long-term immune consequences, highlights emerging treatment options, and delves into important pathways currently being investigated with preclinical models.

Prognostic Value of Serially Estimated Serum Procalcitonin Levels in Traumatic Brain Injury Patients With or Without Extra Cranial Injury on Early In-hospital Mortality: A Longitudinal Observational Study

Background

Traumatic brain injury (TBI) is associated with majority of trauma deaths, and objective tools are required to understand the severity of injury. The application of a biomarker like procalcitonin (PCT) in TBI may allow for assessment of severity and thus aid in prognostication and correlation with mortality and outcome.

Aims

The primary objective is to determine the correlation between PCT concentrations with TBI outcomes (mainly in terms of mortality) at intensive care unit (ICU)/hospital discharge. Secondary objectives are to evaluate correlation with associated extra cranial injuries and complications during hospital stay.

Methods

In total, 186 TBI patients aged > 18 years with minimum survival for at least 12 h admitted to the ICU at the level 1 trauma center were prospectively included in the study and divided into two groups: TBI with and without extra cranial injuries. All admitted patients were treated according to the standard institutional protocol. The PCT levels were obtained on admission, on day 2, and 5. Clinical, laboratory, diagnostic, and therapeutic data were also collected. Primary mortality is defined as death related to central nervous system (CNS) injury, while secondary mortality defined as death related to sepsis or extracranial cause.

Results

Median PCT levels at admission, day 2, and day 5 in TBI patients with extracranial injuries were 3.0, 0.83, and 0.69 ng/ml. In total, primary mortality was observed in 18 (9.7%) patients, while secondary causes were attributable in 20 (12.3%) patients. Regression analysis for primarily CNS cause of mortality showed PCT cutoff level at admission more than 5.5 ng/ml carried sensitivity and specificity of 75%, but for secondary cause (sepsis) of mortality, PCT cutoff values on day 2 > 1.15 ng/ml were derived significant with sensitivity of 70% and specificity of 66%. No significant association of parameters like length of ICU stay, Glasgow outcome scale (GOS), and primary/secondary mortality with the presence of extracranial injuries in TBI patients as compared with TBI alone was noted.

Conclusion

This observational study demonstrates the poor correlation between PCT concentrations with outcome at days 1, 2, and 5 post-injury. The predicted relationship between PCT levels and outcome was not confirmed, and that these results do not support the prognostic utility of PCT biomarker in this population for outcome (mortality) assessment in TBI patients with or without extracranial injuries.

Discontinuation of Antibiotics in Patients with Neurological Conditions - A Study on the Impact of an Antimicrobial Stewardship Program (ASP) in a Tertiary Institution

BACKGROUND

Up to 50% of antibiotics are prescribed either unnecessarily or inappropriately in most hospitals worldwide. In the largest tertiary hospital in Singapore, patients with neurological conditions were often initiated on antibiotics for change in mental state or isolated fevers. We hypothesize that Antimicrobial Stewardship Program (ASP) interventions to discontinue empirical antibiotics in neurological patients with no clinical evidence of bacterial infection are safe. The aim of this study was to compare clinical impact and safety outcomes of ASP interventions between accepted and rejected groups.

METHODS

A retrospective review of the ASP database was conducted for all patients admitted to the neurology department in Singapore General Hospital between January 2014 and December 2017. Interventions were followed up and patients were classified into two intervention groups, the accepted and rejected groups. Demographic data, age-adjusted Charlson co-morbidity index, duration of antibiotic therapy, length of hospital stay post-ASP intervention (PLOS), infection-related readmissions and mortality were compared between the two groups. Data were expressed as mean ± standard deviation for continuous variables, and unpaired Student's t-test was performed to determine intergroup differences between mean values.

RESULTS

The ASP team recommended 184 interventions, with an overall acceptance rate of 82.6% (152/184). There was no significant difference in demographics and age-adjusted Charlson co-morbidity index between the two groups. The accepted group had a shorter duration of therapy by 1.67 days (4.99±2.50 days vs. 6.66±2.34 days; P<0.01) and a shorter PLOS by 2 days, although this was not statistically significant (22.5±22.2 days vs. 24.5±51.4 days; P=0.83). There were no significant differences between the two groups in 14-day mortality and readmission rates.

CONCLUSION

In neurological patients with no clinical evidence of bacterial infections, ASP interventions to discontinue empirical antibiotics were not associated with increased mortality and readmissions but were associated with significant reduction in duration of therapy.

The prognostic value of serum procalcitonin measurements in critically injured patients: a systematic review

Background

Major trauma is associated with high incidence of septic complications and multiple organ dysfunction (MOD), which markedly influence the outcome of injured patients. Early identification of patients at risk of developing posttraumatic complications is crucial to provide early treatment and improve outcomes. We sought to evaluate the prognostic value of serum procalcitonin (PCT) levels after trauma as related to severity of injury, sepsis, organ dysfunction, and mortality.

Methods

We searched PubMed, MEDLINE, EMBASE, the Cochrane Database, and references of included articles. Two investigators independently identified eligible studies and extracted data. We included original studies that assessed the prognostic value of serum PCT levels in predicting severity of injury, sepsis, organ dysfunction, and mortality among critically injured adult patients.

Results

Among 2015 citations, 19 studies (17 prospective; 2 retrospective) met inclusion criteria. Methodological quality of included studies was moderate. All studies showed a strong correlation between initial PCT levels and Injury Severity Score (ISS). Twelve out of 16 studies demonstrated significant elevation of initial PCT levels in patients who later developed sepsis after trauma. PCT level appeared a strong predictor of MOD in seven out of nine studies. While two studies did not show association between PCT levels and mortality, four studies demonstrated significant elevation of PCT levels in non-survivors versus survivors. One study reported that the PCT level of ≥ 5 ng/mL was associated with significantly increased mortality (OR 3.65; 95% CI 1.03–12.9; p = 0.04).

Conclusion

PCT appears promising as a surrogate biomarker for trauma. Initial peak PCT level may be used as an early predictor of sepsis, MOD, and mortality in trauma population.

Chitinase-3-Like Protein 1, Serum Amyloid A1, C-Reactive Protein, and Procalcitonin Are Promising Biomarkers for Intracranial Severity Assessment of Traumatic Brain Injury: Relationship with Glasgow Coma Scale and Computed Tomography Volumetry

OBJECTIVE

The volume and location of intracranial hematomas are well-known prognostic factors for traumatic brain injury. The aim of this study was to determine the relationship of serum biomarkers S100β, glial fibrillary acidic protein, neuron-specific enolase, total tau, phosphorylated neurofilament heavy chain, serum amyloid A1 (SAA1), C-reactive protein, procalcitonin (PCT), and chitinase-3-like protein 1 (YKL-40) with traumatic brain injury severity and the amount and location of hemorrhagic traumatic lesions.

METHODS

A prospective observational cohort of 115 patients with a Glasgow Coma Scale (GCS) score of 3-15 were evaluated. Intracranial lesion volume was measured from the semiautomatic segmentation of hematoma on computed tomography using Analyze software. The establishment of possible biomarker cutoff points for intracranial lesion detection was estimated using the Youden Index (J) obtained from the area under the receiver operating characteristic curve.

RESULTS

SAA1, YKL-40, PCT, and S100β showed the most robust association with level of consciousness, both with total GCS and motor score. Biomarkers significantly correlated with volumetric measurements of subdural hematoma, traumatic subarachnoid hemorrhage, intraparenchymal hemorrhage, intraventricular hemorrhage, and total amount of bleeding. The type of intracranial hemorrhage was associated with various release patterns of neurobiochemical markers.

CONCLUSIONS

YKL-40, SAA1, C-reactive protein, and PCT combined with S100β were the most promising biomarkers to determine the presence, location, and extent of traumatic intracranial lesions. Combination of biomarkers further increased the discriminatory capacity for the detection of intracranial bleeding.

Procalcitonin-guided antibiotic therapy for septic patients in the surgical intensive care unit

In critically ill patients, elucidating those patients with the systemic inflammatory response syndrome (SIRS) from an infectious source (sepsis), versus those who have SIRS without infection, can be challenging since the clinical features are the same.

Even with strict monitoring and testing, 39–98 % of patients with SIRS will never have bacteriological confirmation of an infection, and 6–17 % of patients with a documented infection will not show signs of SIRS. Due to this overlap, an extensive amount of research has been performed to investigate ways of determining and separating SIRS from infection, compared to SIRS due to trauma, surgical stress, or other non-infectious causes. This review article will discuss the recommended and peer-approved use of procalcitonin in septic patients in the intensive care unit and its use as a guide to antibiotic initiation and termination. The article will focus on the prospective randomized trials (Level 1 evidence) that have been conducted, and lesser levels of evidence will be referenced as needed to substantiate a conclusion.

The literature documents multiple benefits of using procalcitonin as a guide to cost savings and appropriate termination of antibiotics by its use as a new objective marker of bacteremia that was previously not available. This article will show that antibiotics should be terminated when the procalcitonin level falls below 0.5 ng/mL.