Should serial monitoring of procalcitonin be done routinely in critically ill patients of ICU: A systematic review and meta-analysis

Mortality prediction model from combined serial lactate, procalcitonin and calprotectin levels in critically ill patients with sepsis: A retrospective study according to Sepsis-3 definition

OBJECTIVE

1) To evaluate the ability of baseline and on 24 h serum calprotectin, in comparison to canonical biomarkers (lactate and procalcitonin), for prognosis of 28-day mortality in critically ill septic patients; and 2) To develop a predictive model combining the three biomarkers.

DESIGN

A single-center, retrospective study.

SETTING

Intensive Care Unit of a university hospital.

PATIENTS OR PARTICIPANTS

One hundred and seventy three septic pacientes were included.

INTERVENTIONS

Measurement of baseline lactate, procalcitonin and calprotectin level and procalcitonin and calprotectin levels on 24 h.

MAIN VARIABLES OF INTEREST

Demographics and comorbidities, SOFA score on ICU admission, baseline lactate, procalcitonin and calprotectin on admission and on 24 h and 28-day mortality.

RESULTS

1) On ICU admission, lactate was the only biomarker achieving a significant accuracy (AUC: 0.698); 2) On 24 h, no differences were found on procalcitonin and calprotectin levels. Procalcitonin and calprotectin clearances were significantly lower in non-survivors and both achieved a moderate performance (AUCs: 0.668 and 0.664, respectively); 3) A biomarker based-model achieved a significant accuracy (AUC: 0.766), trending to increase (AUC: 0.829) to SOFA score alone; y 4) Baseline lactate levels and procalcitonin and calprotectin clearance were independent predictors for the outcome.

CONCLUSIONS

1) Baseline and on 24 h calprotectina and procalcitonin levels lacked ability in predicting 28-day mortality; 2) Accuracy of clearance of both biomarkers was moderate; and 3) Combination of SOFA score and the predictive biomarker based-model showed a high prognostic accuracy.

Changes of Procalcitonin Kinetics According to Renal Clearance in Critically Ill Patients with Primary Gram-Negative Bloodstream Infections

Objective

This study aimed to investigate the relationship between procalcitonin (PCT) kinetic and estimated glomerular filtration rates (eGFR) in critically ill patients who had Gram-negative primary bloodstream infection (GN-BSI) and responded to the antimicrobial therapy.

Materials and Methods

This single-centered study was retrospective and observational. Critically ill GN-BSI patients over 18 years old who had clinical and microbiological responses to antibiotic treatment were included in the study. Patients were divided into two groups according to eGFR (eGFR <30 mL/min/1.73m2 and ≥30 mL/min/1.73m2) and compared for PCT kinetic at seven different measurement points as initial, first, third, fifth, seventh, tenth, and fourteenth days.

Results

The study included 138 patients. Initial PCT levels were higher in patients with eGFR <30 mL/min/1.73m2 (4.58 [1.36-39.4] ng/mL) than in eGFR ≥30 mL/min/1.73m2 (0.91 [0.32-10.2]) (p<0.001). This elevation was present at all measurement points (p<0.05). The decrease in PCT values by ≥30% (26.0% vs 47.9%; p=0.024) on the third day and ≥50% (69.2% vs 76.6%; p=0.411) on the fifth day was less in the low eGFR (<30 mL/min/1.73m2) group. The effect of low GFR on serum PCT kinetic was present in both fermenter and non-fermenter GN-BSIs but was more prominent in the fermenter group.

Conclusion

Serum PCT levels during therapy were higher in patients with low eGFR. Early PCT (<5 days) response was not obtained in non-fermenter GN-BSI patients with low eGFR. Antibiotic revision decisions should be made more carefully in patients with low eGFR due to high initial PCT levels and slow PCT kinetic.

Serial Trend of Neutrophil CD64, C-reactive Protein, and Procalcitonin as a Prognostic Marker in Critically Ill Patients with Sepsis/Septic Shock: A Prospective Observational Study from a Tertiary Care ICU

Aim and background

Neutrophil CD64 (nCD64) is evolving as a prognostic biomarker in sepsis. The primary objective of this study was to evaluate whether serial trend of nCD64, procalcitonin (PCT), and C-reactive protein (CRP) predict 28-day mortality in patients with sepsis/septic shock, as per Sepsis-3 criteria.

Materials and methods

This prospective, observational single-center cohort study included 60 adult patients (age ≥18 years) with sepsis. Serial biomarker levels with SOFA score were measured at admission (day 0), on day 4, and on day 8.

Results

Of the 60 patients, 42 (70%) had septic shock. Biomarker levels at admission did not differ between patients with sepsis and septic shock. Thirty-seven patients survived and 23 were non-survivors by day 28. There was a significant fall in serial trend of all three biomarkers from admission till day 8 (Friedman p < 0.001) in survivors compared to a non-significant change in non-survivors. On multivariate analysis, SOFA score at admission (OR 1.731), more days with vasopressor support (OR 1.077), rise in CD64 from day 0 to day 8 (OR 1.074), and rise in CRP from day 0 to 8 (OR 1.245) were the significant predictors of 28-day mortality (p < 0.05). The highest area under the ROC curve was obtained for more days of vasopressor therapy (0.857), followed by a rise in CD64 from day 0 to day 8 (0.798).

Conclusion

Serial trend of biomarkers has prognostic utility. The rise in CD64 from day 0 to day 8 was a good predictor of mortality compared to the trend of other biomarkers.

How to cite this article

Patnaik R, Azim A, Singh K, Agarwal V, Mishra P, Poddar B, et al. Serial Trend of Neutrophil CD64, C-reactive Protein, and Procalcitonin as a Prognostic Marker in Critically Ill Patients with Sepsis/Septic Shock: A Prospective Observational Study from a Tertiary Care ICU. Indian J Crit Care Med 2024;28(8):777-784.

Utility of Serum Procalcitonin and Its Clearance in Predicting Outcomes in COVID-19 Patients

Introduction Identification of coronavirus disease 2019 (COVID-19) patients at risk of worse clinical outcomes is crucial to improving patient care. Various biochemical markers have been used to predict outcomes in such patients. We aimed to evaluate the role of serum PCT (procalcitonin) and the utility of PCT clearance (PCTc) in predicting the outcome of patients with COVID-19 illness. Methods We prospectively included 39 patients with severe or critical COVID-19 illness with an age equal to more than 18 years. In addition to routine baseline investigations, serum PCT was measured at admission (PCT1) and day 5 of hospitalization (PCT2). PCTc was calculated using the formula [Formula: see text]. Results We observed that serum PCT at admission was significantly higher in non-survivors (median: 1.9 ng/ml IQR: 0.51-4.23) compared to survivors (median 0.35 (IQR: 0.1-1.2), p 0.002). On serial serum-PCT estimation, non-survivors had persistently elevated serum-PCT (median PCT1:1.9 ng/ml (IQR: 0.51-4.23) to median PCT2: 1.9ng/ml (IQR: 0.83-2.72), p 0.51) than survivors (median PCT1:0.35ng/ml (IQR: 0.1-1.19) to median PCT2: 0.15ng/ml (IQR: 0.05-0.29), p 0.01). However, no difference in serum PCTc was observed between the two groups (median: 35.3% (IQR: 12.5-84.9) in survivors vs. 71.7% (33.3-91.7) in non-survivors, p = 0.165). Conclusion Serum PCT is a potential biochemical marker that could predict outcomes in COVID-19 patients. Measurement of serial serum PCT and estimation of PCT clearance may serve as better predictors than a single value; however, well-designed studies are required to identify the definite role of serum PCT in COVID-19 patients of varying severity.

Retrograde ureteral catheterization under local anesthesia for emergency drainage in patients with infection and hydronephrosis secondary to ureteral calculi: Experience from a tertiary care hospital

Objectives

The aim is to evaluate the safety and efficacy of retrograde ureteral catheterization under local anesthesia in patients with urinary tract infections complicated by hydronephrosis caused by ureteral stone obstruction.

Materials and Methods

From October 2020 to September 2021, a retrospective analysis of patients' medical records was performed. Records of past history, physical examination, laboratory tests, and imaging investigations were reviewed. Retrograde ureteric stent (RUS) was performed under local anesthesia using cystoscopes and guided by portable fluoroscopy. Real-time fluoroscopy was used to verify the double-J stent position and confirm a smooth process. The postoperative recovery and length of admission were also recorded.

Results

A total of 14 patients with ureteral stone obstruction with infective hydronephrosis received 15 total emergency RUS procedures (one bilateral). Intraoperative findings, operation times, and infection signs were recorded and analyzed. All patients met systemic infection criteria, with a mean body temperature of 38.7°C ± 1.7°C. Leukocytosis was noted in 8 (57.1%) patients. Elevated C-reactive protein (8.5 ± 6.3 mg/L) and procalcitonin (24.1 ± 22.0 ng/mL) were found in 13 (92.9%) and 9 (64.3%) patients, respectively. Mean stone size was 8.5 ± 6.3 mm, mostly localized to the upper ureter (upper: 12; middle: 0; lower: 3). Mean operation time was 14.1 ± 4.3 min. After emergency drainage, all patients improved and were discharged after infection was controlled. The average length of admission was 6.2 ± 2.2 days.

Conclusion

RUS under local anesthesia is safe and effective for treating infective hydronephrosis due to ureteral stone obstruction. A randomized controlled trial with a large sample remains necessary to validate these findings.

Biomarkers in sepsis-looking for the Holy Grail or chasing a mirage!

Sepsis is defined as a life-threatening organ dysfunction caused by the dysregulated host response to infection. It is a complex syndrome and is characterized by physiologic, pathologic and biochemical abnormalities in response to an infection. Diagnosis of sepsis is based on history, physical examination and other investigations (including biomarkers) which may help to increase the certainty of diagnosis. Biomarkers have been evaluated in the past for many diseases and have been evaluated for sepsis as well. Biomarkers may find a possible role in diagnosis, prognostication, therapeutic monitoring and anti-microbial stewardship in sepsis. Since the pathophysiology of sepsis is quite complex and is incompletely understood, a single biomarker that may be robust enough to provide all information has not been found as of yet. However, many biomarkers have been studied and some of them have applications at the bedside and guide clinical decision-making. We evaluated the PubMed database to search for sepsis biomarkers for diagnosis, prognosis and possible role in antibiotic escalation and de-escalation. Clinical trials, meta-analyses, systematic reviews and randomized controlled trials were included. Commonly studied biomarkers such as procalcitonin, Soluble urokinase-type plasminogen activator (Supar), presepsin, soluble triggering receptor expressed on myeloid cells 1, interleukin 6, C-reactive protein, etc., have been described for their possible applications as biomarkers in septic patients. The sepsis biomarkers are still an area of active research with newer evidence adding to the knowledge base continuously. For patients presenting with sepsis, early diagnosis and prompt resuscitation and early administration of anti-microbials (preferably within 1 h) and source control are desired goals. Biomarkers may help us in the diagnosis, prognosis and therapeutic monitoring of septic patients. The marker redefining our view on sepsis is yet a mirage that clinicians and researchers continue to chase.

Low-cost, facile droplet modification of screen-printed arrays for internally validated electrochemical detection of serum procalcitonin

This manuscript presents the design and facile production of screen-printed arrays (SPAs) for the internally validated determination of raised levels of serum procalcitonin (PCT). The screen-printing methodology produced SPAs with six individual working electrodes that exhibit an inter-array reproducibility of 3.64% and 5.51% for the electrochemically active surface area and heterogenous electrochemical rate constant respectively. The SPAs were modified with antibodies specific for the detection of PCT through a facile methodology, where each stage simply uses droplets incubated on the surface, allowing for their mass-production. This platform was used for the detection of PCT, achieving a linear dynamic range between 1 and 10 ng mL^-1 with a sensor sensitivity of 1.35 × 10^-10 NIC%/ng mL^-1. The SPA produced an intra- and inter-day %RSD of 4.00 and 5.05%, with a material cost of £1.14. Internally validated human serum results (3 sample measurements, 3 control) for raised levels of PCT (>2 ng mL^-1) were obtained, with no interference effects seen from CRP and IL-6. This SPA platform has the potential to offer clinicians vital information to rapidly begin treatment for "query sepsis" patients while awaiting results from more lengthy remote laboratory testing methods. Analytical ranges tested make this an ideal approach for rapid testing in specific patient populations (such as neonates or critically ill patients) in which PCT ranges are inherently wider. Due to the facile modification methods, we predict this could be used for various analytes on a single array, or the array increased further to maintain the internal validation of the system.

Monitoring of the Forgotten Immune System during Critical Illness-A Narrative Review

Immune organ failure is frequent in critical illness independent of its cause and has been acknowledged for a long time. Most patients admitted to the ICU, whether featuring infection, trauma, or other tissue injury, have high levels of alarmins expression in tissues or systemically which then activate innate and adaptive responses. Although necessary, this response is frequently maladaptive and leads to organ dysfunction. In addition, the counter-response aiming to restore homeostasis and repair injury can also be detrimental and contribute to persistent chronic illness. Despite intensive research on this topic in the last 40 years, the immune system is not routinely monitored in critical care units. In this narrative review we will first discuss the inflammatory response after acute illness and the players of maladaptive response, focusing on neutrophils, monocytes, and T cells. We will then go through commonly used biomarkers, like C-reactive protein, procalcitonin and pancreatic stone protein (PSP) and what they monitor. Next, we will discuss the strengths and limitations of flow cytometry and related techniques as an essential tool for more in-depth immune monitoring and end with a presentation of the most promising cell associated markers, namely HLA-DR expression on monocytes, neutrophil expression of CD64 and PD-1 expression on T cells. In sum, immune monitoring critically ill patients is a forgotten and missing piece in the monitoring capacity of intensive care units. New technology, including bed-side equipment and in deep cell phenotyping using emerging multiplexing techniques will likely allow the definition of endotypes and a more personalized care in the future.

A Literature Overview of Secondary Peritonitis Due to Carbapenem-Resistant Enterobacterales (CRE) in Intensive Care Unit (ICU) Patients

This comprehensive review of the recently published literature offers an overview of a very topical and complex healthcare problem: secondary peritonitis from multidrug-resistant pathogens, especially carbapenem-resistant Enterobacterales (CRE). Spontaneous secondary peritonitis and postsurgical secondary peritonitis are among the major causes of community- and healthcare- acquired sepsis, respectively. A large number of patients enter ICUs with a diagnosis of secondary peritonitis, and a high number of them reveal infection by CRE, P. aeruginosa or A. baumannii. For this reason, we conceived the idea to create a synthetic report on this topic including updated epidemiology data, a description of CRE resistance patterns, current strategies of antimicrobial treatment, and future perspectives. From this update it is clear that antimicrobial stewardship and precision medicine are becoming essential to fight the emergence of antimicrobial resistance and that even if there are new drugs effective against CRE causing secondary peritonitis, these drugs have to be used carefully especially in empirical therapy.

Novel biomarker panel for the diagnosis and prognosis assessment of sepsis based on machine learning

Background: The authors investigated a panel of novel biomarkers for diagnosis and prognosis assessment of sepsis using machine learning (ML) methods. Methods: Hematological parameters, liver function indices and inflammatory marker levels of 332 subjects were retrospectively analyzed. Results: The authors constructed sepsis diagnosis models and identified the random forest (RF) model to be the most optimal. Compared with PCT (procalcitonin) and CRP (C-reactive protein), the RF model identified sepsis patients at an earlier stage. The sepsis group had a mortality rate of 36.3%, and the RF model had greater predictive ability for the 30-day mortality risk of sepsis patients. Conclusion: The RF model facilitated the identification of sepsis patients and showed greater accuracy in predicting the 30-day mortality risk of sepsis patients.

A Pilot Assessment on the Role of Procalcitonin Dynamic Monitoring in the Early Diagnosis of Infection Post Cardiac Surgery

Purpose

To evaluate the value of dynamic monitoring of procalcitonin (PCT) as a biomarker for the early diagnosis of postoperative infections in patients undergoing cardiac surgery.

Methods

In total, 252 patients who underwent cardiac surgery were retrospectively included. The postoperative patients’ PCT level, change value (△PCT), and clearance rate (△PCTc) were compared between the infected and noninfected groups in adult and pediatric patients on postoperative days (PODs) 1, 3, and 5. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the diagnostic value.

Results

Procalcitonin concentration decreased progressively in the noninfected group in adult and pediatric patients; PCT concentration continued to rise until it peaked on POD 3 in the infected group. In adult patients, the AUC of PCT for diagnosis of infection on PODs 1, 3, and 5 were 0.626, 0.817, and 0.806, with the optimal cut-off values of 7.35, 3.63, and 1.73 ng/ml, respectively. The diagnostic efficiency of △PCT₃ and △PCT_C3 was significantly better than △PCT₅ and △PCT_C5, respectively. In pediatric patients, the AUC of PCT for diagnosis of infection on PODs 1, 3, and 5 were 0.677, 0.747, and 0.756, respectively, and the optimal cut-off values were 27.62, 26.15, and 10.20 ng/ml.

Conclusion

This study showed that dynamic monitoring of PCT levels could be an effective clinical means to help to discover postoperative infection earlier. The PCT level and its change indicators on POD 3 in adult patients and the PCT level on POD 5 in children can indicate infection.

Efficacy of Oxymatrine Plus Antiviral in the Treatment of Sepsis and Its Effect on the Levels of Endotoxin and Inflammatory Factors

Objective

To assess the clinical efficacy of oxymatrine plus antiviral therapy in the treatment of sepsis and its effects on the levels of endotoxin and inflammatory factors. Methodology. 90 patients with sepsis were selected for retrospective analysis and were assigned to receive either conventional treatment (control group) or oxymatrine plus antiviral treatment (study group). The clinical endpoint was treatment efficacy.

Results

There were no significant differences in baseline patient profile between the two groups (P > 0.05). The study group showed a higher efficiency versus the control group (P < 0.05). Patients in the study group had a significantly shorter mechanical ventilation duration and ICU stay versus those in the control group (P < 0.05). Both groups had reduced Acute Physiology and Chronic Health Evaluation II (APACHE II) score, Marshall score, levels of endotoxin, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-8, C-reactive protein (CRP), and procalcitonin (PCT) after treatment, with lower results in the study group versus the control group (P < 0.05).

Conclusion

Oxymatrine plus antiviral therapy effectively improves clinical efficacy, reduces the levels of endotoxin and inflammatory factors, protects organ function, and boosts recovery. Further clinical trials are, however, required prior to general application in clinical practice.

Prognostic Value of Mid-Regional Proadrenomedullin Sampled at Presentation and after 72 Hours in Septic Patients Presenting to the Emergency Department: An Observational Two-Center Study

The prognostic value of mid-regional proADM (MR-proADM) in septic patients presenting to the emergency department (ED) is not well established. In this prospective observational study enrolling septic patients evaluated in two EDs, MR-proADM was measured at arrival (t0) and after 72 h (t72). MR-proADM%change was calculated as follows: (MR-proADMt72h − MR-proADMt0)/MR-proADMt0. In total, 147 patients were included in the study, including 109 with a final diagnosis of sepsis and 38 with septic shock, according to the Sepsis-3 criteria. The overall 28-day mortality (outcome) rate was 12.9%. The AUC for outcome prognostication was 0.66 (95% CI 0.51–0.80) for MR-proADMt0, 0.77 (95% CI 0.63–0.92) for MR-proADMt72 and 0.74 (95% CI 0.64–0.84) for MR-proADM%change. MR-proADMt0 ≥ 2.78 nmol/L, MR-proADMt72 ≥ 2.7 nmol/L and MR-proADM%change ≥ −15.2% showed statistically significant log-rank test results and sensitivity/specificity of 81/65%, 69/80% and 75/70% respectively. In regression analysis, MR-proADM%change was a significant outcome predictor both in univariate and multivariate analysis, after adjustment for age, SOFA and APACHEII scores, providing up to 80% of added prognostic value. In conclusion, time trends of MR-proADM may provide additional insights for patient risk stratification over single sampling. MR-proADM levels sampled both at presentation and after 72 h predicted 28-day survival in septic patients presenting to the ED.

Precision medicine in sepsis and septic shock: From omics to clinical tools

Sepsis is a heterogeneous disease with variable clinical course and several clinical phenotypes. As it is associated with an increased risk of death, patients with this condition are candidates for receipt of a very well-structured and protocolized treatment. All patients should receive the fundamental pillars of sepsis management, which are infection control, initial resuscitation, and multiorgan support. However, specific subgroups of patients may benefit from a personalized approach with interventions targeted towards specific pathophysiological mechanisms. Herein, we will review the framework for identifying subpopulations of patients with sepsis, septic shock, and multiorgan dysfunction who may benefit from specific therapies. Some of these approaches are still in the early stages of research, while others are already in routine use in clinical practice, but together will help in the effective generation and safe implementation of precision medicine in sepsis.

A Research Agenda for Diagnostic Excellence in Critical Care Medicine

Diagnosing critically ill patients in the intensive care unit is difficult. As a result, diagnostic errors in the intensive care unit are common and have been shown to cause harm. Research to improve diagnosis in critical care medicine has accelerated in past years. However, much work remains to fully elucidate the diagnostic process in critical care. To achieve diagnostic excellence, interdisciplinary research is needed, adopting a balanced strategy of continued biomedical discovery while addressing the complex care delivery systems underpinning the diagnosis of critical illness.