Procalcitonin assay in systemic inflammation, infection, and sepsis: clinical utility and limitations. Crit Care Med. 2008;36:941-952. [PMID: 18431284 DOI: 10.1097/ccm.0b013e318165babb]

Electrocardiographic alterations and raised procalcitonin levels during anaphylactic shock

Anaphylaxis represents a systemic disease occurring after the exposure to an allergen. Drugs for the treatment of anaphylactic reactions (ie, corticosteroids and adrenalin) could induce autonomic alterations, such as tachycardia, hyperthermia, tachypnoea and leucocytosis. We describe the case of a 52-year-old woman presenting with a severe allergic reaction after the ingestion of amoxicillin-clavulanate. The occurrence of ECG alterations, laboratory abnormalities and procalcitonin (PCT) elevation will be discussed with particular emphasis on the possible misleading role of PCT during anaphylactic shock.

Biosensors for detecting viral and bacterial infections using host biomarkers: a review

A schematic diagram showing multiple modes of biosensing platforms for the diagnosis of bacterial or viral infections.

Management of anastomotic leakage after rectal surgery: a review article

Anastomotic leaks (ALs) are associated with increased perioperative morbidity and mortality, prolonged length of stay, higher readmission rates, the potential need for further operative interventions, and unintended permanent stomas; resulting in increased hospital costs and resource use, and decreased quality of life. This review article is to present definition, diagnosis and management strategies for AL after rectal surgery.

Serum procalcitonin and C-reactive protein in the evaluation of bacterial infection in generalized pustular psoriasis

Background

There is an obvious need for more prompt and specific biomarkers of bacterial infections in generalized pustular psoriasis patients.

Objective

The aim of this study was to evaluate the diagnostic properties and define appropriate cut-off values of procalcitonin and C-reactive protein in predicting bacterial infection in generalized pustular psoriasis patients.

Methods

Sixty-four generalized pustular psoriasis patients hospitalized from June 2014 to May 2017 were included in this retrospective study. The values of procalcitonin, C-reactive protein, details of infection, and other clinical parameters were analyzed.

Results

Receiver operating characteristic curve analysis generated similar areas (p = 0.051) under the curve for procalcitonin 0.896 (95% CI 0.782–1.000) and C-reactive protein 0.748 (95% CI 0.613–0.883). A cut-off value of 1.50 ng/mL for procalcitonin and 46.75 mg/dL for C-reactive protein gave the best combination of sensitivity (75.0% for procalcitonin, 91.7% for C-reactive protein) and specificity (100% for procalcitonin, 53.8% for C-reactive protein). Procalcitonin was significantly positively correlated with C-reactive protein levels both in the infected (r = 0.843, p = 0.040) and non-infected group (r = 0.799, p = 0.000).

Study limitations

The sample size and the retrospective design are limitations.

Conclusions

The serum levels of procalcitonin and C-reactive protein performed equally well to differentiate bacterial infection from non-infection in generalized pustular psoriasis patients. The reference value of procalcitonin and C-reactive protein applied to predicting bacterial infection in most clinical cases may not be suitable for generalized pustular psoriasis patients. C-reactive protein had better diagnostic sensitivity than procalcitonin; however, the specificity of procalcitonin was superior to that of C-reactive protein.

Predictive value of procalcitonin in chronic allograft dysfunction in kidney transplant recipients

The present study was designed to determine the potential role of circulating procalcitonin (PCT) in predicting chronic allograft dysfunction (CAD) in kidney transplant recipients (KTRs). A total of 87 KTRs were retrospectively analyzed and divided into a CAD and a non-CAD (normal renal function) group. Clinical features and inflammatory markers were compared between the groups, including PCT, white blood cell count, C-reactive protein, neutrophil percentage (N%) and lipoprotein(a) [Lp(a)], and the receiver operating characteristic (ROC) curve for CAD prediction was plotted. Univariate and multivariate logistic regression analyses were used to analyze the relevant risk factors for CAD. The results indicated that i) the values of these indicators in the CAD group, including the male ratio, years after transplantation, PCT, N% and Lp(a), were significantly higher than those in the non-CAD group, while the body mass index, aspartate aminotransferase, high-density lipoprotein and low-density lipoprotein were significantly lower; ii) PCT and Lp(a) were able to predict CAD with an area under the ROC curve of 0.893 and 0.770, respectively; iii) multivariate logistic regression analysis of factors influencing CAD in KTRs suggested that elevated PCT was an independent risk factor. In KTRs, PCT was identified as a potential biomarker for predicting CAD.

Procalcitonin and D-dimer for Predicting 28-Day-Mortality Rate and Sepsis Severity based on SOFA Score; A Cross-sectional Study

Objective:

To determine the possible relationship of procalcitonin (PCT) and D-dimer with the 28-day-mortality rate and severity of sepsis based on sequential organ failure assessment (SOFA) score.

Methods:

In this cross-sectional study, patients were enrolled based on their signs and symptoms of sepsis confirmed by essential laboratory studies. Demographic data, Glasgow coma scale and vital signs, serum PCT and D-dimer levels, creatinine, bilirubin level, arterial blood gas analysis and platelet count were recorded. Disease severity index was assessed based on SOFA score. Patients’ 28-day-mortality rate and hospital length of stay were compared with the study variables.

Results:

Sixty-four patients with the mean age of 78.3±11.6 were included of whom 34 cases (53.1%) were male. The 28-day-mortality rate was 17%. The analysis showed that only patients’ age (p=0.01) and platelet count (p=0.02) had a statistically significant association with the mortality rate. SOFA score had no statistically significant correlation with PCT or D-dimer; and these two markers didn’t have any significant correlation in terms of predicting mortality due to the sepsis.

Conclusion:

In our study, PCT and D-dimer failed to show any significant correlation with 28-day-mortality rate of sepsis.

Procalcitonin Levels in Critically Ill Children With Status Asthmaticus

BACKGROUND

Children with status asthmaticus (SA) often present with fever and are evaluated with chest radiographs (CXRs). In the absence of a confirmatory test for bacterial infection, antibiotics are started whenever there are radiological infiltrates or if there is a suspicion of pneumonia. We undertook this study to determine if serum procalcitonin (PCT) levels at admission are altered in critically ill children with SA. We also sought to determine if serum PCT levels are elevated in children with radiological infiltrates or in children who were treated with antibiotics.

METHODS

This is a prospective single-center observational study evaluating serum PCT levels in critically ill children with SA. Study subjects included children 1 to 21 years old, admitted to a pediatric intensive care unit (PICU) with SA between March 2012 and April 2013. For the purposes of this study, patients whose CXRs were read by the radiologist as probable bacterial pneumonia was defined as having "radiological bacterial pneumonia," whereas patients who received antibiotics by the treating physician were defined as having "clinician-diagnosed pneumonia."

RESULTS

Sixty-one patients with a median age of 7.3 years (interquartile range, 4-10 years) were included in the study. Fifty-one percent were male. Average Pediatric Risk of Mortality III score was 2.7 (SD, 2.9). Three patients (5%) were determined to have radiological bacterial pneumonia, whereas 52 (85%) did not. Six patients (10%) were indeterminate. The mean PCT level for all patients was 0.65 (SD, 1.54) ng/mL, whereas the median PCT level was 0.3 ng/mL. There was no significant difference in the mean PCT levels between the patients with and without clinician-diagnosed pneumonia (0.33 [SD, 0.36] vs 0.69 [SD, 1.67], P = 0.44). Using a PCT cutoff level of 0.5 ng/mL, a significant association was found with the presence of fever (P = 0.004), but no significant association was found with the presence of CXR infiltrates, radiological bacterial pneumonia, hospital length of stay, PICU length of stay, Pediatric Risk of Mortality III scores, or receipt of antibiotics.

CONCLUSIONS

Serum PCT level was not elevated to greater than 0.5 ng/mL in 75% of this cohort of critically ill children with SA admitted to PICU. Presence of CXR infiltrates was not associated with higher PCT levels. Large clinical trials are needed to study the diagnostic and predictive role of PCT in this patient population.

Diagnosing infection after infant open heart surgery: role of procalcitonin

Background

Diagnosing infection in infants after cardiac surgery with cardiopulmonary bypass remains challenging. We aimed to determine whether procalcitonin discriminates post-cardiopulmonary bypass systemic inflammatory response syndrome from bacterial infection in infants better than C-reactive protein and leukocyte count.

Method

One hundred and eight infants underwent cardiac surgery with cardiopulmonary bypass. Leukocyte count, C-reactive protein, and procalcitonin were measured on arrival in the intensive care unit as baseline, and repeated on postoperative day 3. Bacterial infection was defined as proven infection with a positive blood or sputum culture.

Results

Twenty-four infants had proven bacterial infection. Baseline leukocyte counts and C-reactive protein levels did not differ significantly between the 2 groups. On postoperative day 3, C-reactive protein (62 vs. 38.5 mg·L−1, p = 0.01) and procalcitonin levels (6.58 vs. 0.41 ng·mL−1, p < 0.01) were higher in patients with bacterial infection. Leukocyte counts did not differ significantly between the two groups ( p = 0.94). The area under the receiver operating curve for leukocyte count, C-reactive protein, and procalcitonin was 0.49 ( p = 0.94), 0.67 ( p = 0.01), and 0.87 ( p < 0.0010), respectively. The optimal cutoff value of procalcitonin was 2.5 ng·mL−1 (sensitivity 75%, specificity 88%).

Conclusion

In infants undergoing cardiac surgery with cardiopulmonary bypass, procalcitonin discriminates bacterial infection from post-cardiopulmonary bypass systemic inflammatory response syndrome better than C-reactive protein and leukocyte count.

Potential of serum procalcitonin in predicting bacterial exacerbation and guiding antibiotic administration in severe COPD exacerbations: a systematic review and meta-analysis

Background: The value of procalcitonin (PCT) in the diagnosis of bacterial infections and for determining antibiotic usage among patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is currently unclear. Methods: We systematically reviewed the literature and selected studies that evaluated PCT as a biomarker for predicting bacterial infection and compared PCT-based protocols to determine its application in the initiation or discontinuation of antibiotics. Guidance for systematic reviews from Cochrane and the GRADE were followed to perform this study. Data were pooled and analyzed by using a random-effects or a fixed-effects model based on the heterogeneity. Results: The pooled sensitivity and specificity of PCT in diagnosing respiratory bacterial infections were 0.60 and 0.76, respectively, with the area under the summary receiver operating characteristic curve of 0.77. Subgroup analysis showed that the sensitivity and specificity of PCT for patients in ICU were 0.48 and 0.69, respectively. PCT-based protocols decreased antibiotic prescription (relative risk = 0.66, 95% CI: 0.62-0.71) and total antibiotic exposure (mean difference = -2.60, 95% CI: -4.48-0.72), without affecting clinical outcomes such as treatment failure, length of hospitalization and rates of re-exacerbation or overall mortality. Conclusions: PCT has a moderate ability to distinguish bacterial respiratory infection in patients with AECOPD. PCT-guided algorithm can reduce unnecessary administration of antibiotics without increasing adverse outcomes. However, for patients requiring admission in the ICU, PCT may have a poor diagnostic value, and the PCT-guided algorithm may not effectively and safely reduce the antibiotic exposure.

A semi-quantitative rapid multi-range gradient lateral flow immunoassay for procalcitonin

A rapid semi-quantitative gradient lateral flow immunoassay (LFIA) of procalcitonin (PCT), a peptide precursor of the hormone calcitonin, was developed. The method is based on particular analyte cut-offs by immobilizing specific antibodies on the test strip with a consistent (gradient) increase in concentration from line to line. Semi-quantitative multi-range analysis is evaluated visually by counting the number of colored test lines corresponding to a certain concentration range of sepsis marker: [PCT]˂0.25; 0.25 ≤ [PCT] < 0.5; 0.5 ≤ [PCT] < 2; 2 ≤ [PCT] < 10; [PCT] ≥ 10 ng·mL^-1. This multi-range gradient LFIA was implemented by using two types of label: spherical gold nanoparticles (35 nm) and hierarchical popcorn-like gold nanoparticles (100 nm). The comparison of this LFIA with an ELISA (for n = 82) yielded 87.5% and 76.6% sensitivities, and 92.3% and 92.3% specificities, respectively. Thus, multi-range gradient LFIA performs well at PCT thresholds, which is important for early diagnosis of sepsis and severe bacterial infection. In our perception, this method has a wide scope in that it may be implemented in numerous other LFIA based test systems. Graphical abstract Schematic of the gradient lateral flow immunoassay for determination of clinically relevant procalcitonin ranges. It allows to reach the correlation between the number of developed test lines and procalcitonin concentration range in serum by pre-immobilization of capture antibodies in a consistently (gradient) increasing concentration.

Combining procalcitonin with the qSOFA and sepsis mortality prediction

To investigate whether procalcitonin (PCT) can improve the performance of quick sequential organ failure assessment (SOFA) score in predicting sepsis mortality, we conducted a retrospective multicenter cohort study with independent validation in a prospectively collected cohort in 3 tertiary medical centers. Patients with presumed sepsis were included. Serum PCT levels were measured at admission. Quick SOFA score and systemic inflammatory response syndrome (SIRS) criteria were calculated for each patient. PCT levels were assigned into 0, 1, and 2 points for a serum level of <0.25, 0.25 to 2, and >2 ng/mL, and added to the quick sepsis-related organ failure assessment (qSOFA) score. The incremental value of PCT to qSOFA was then evaluated by logistic regression, receiver-operating characteristic (ROC) curve, and reclassification analysis.In all, 1318 patients with presumed severe infection were enrolled with a 30-day mortality of 13.5%. Serum level of PCT showed a high correlation with qSOFA score and 30-day inhospital mortality. The area under the ROC curve was 0.56 for SIRS criteria, 0.67 for qSOFA score, and 0.73 for qSOFA_PCT in predicting 30-day mortality. The risk prediction improvement was reflected by a net reclassification improvement of 35% (17%-52%). Incorporation of PCT into the qSOFA model could raise the sensitivity to 86.5% (95% confidence interval 80.6%-91.2%). In the validation cohort, qSOFA_PCT greatly improved the sensitivity to 90.9%.A simple modification of qSOFA score by adding the ordinal scale of PCT value to qSOFA could greatly improve the suboptimal sensitivity problem of qSOFA and may serve as a quick screening tool for early identification of sepsis.

Assessment of Apoptosis Inhibitor of Macrophage/CD5L as a Biomarker to Predict Mortality in the Critically Ill With Sepsis

BACKGROUND

To determine the utility of apoptosis inhibitor of macrophage (AIM)/CD5L as a potentially novel biomarker of morbidity and mortality in patients with sepsis who are critically ill.

METHODS

There were 150 adult patients with sepsis studied. Serum AIM levels on day of ICU admission were determined and compared with survival status and organ dysfunction. For validation, 60 adult patients with sepsis from another medical center were studied. Furthermore, the role of AIM as an outcome predictor in 51 pediatric patients with sepsis was investigated.

RESULTS

In the derivation cohort of adult patients, patients with sepsis had markedly increased admission levels of serum AIM compared with ICU control subjects and healthy control subjects. Higher serum AIM levels at admission were significantly associated with higher Sequential (sepsis-related) Organ Failure Assessment (SOFA) scores. On day of ICU admission, the area under the receiver operating characteristic curve (AUC) for AIM level association with 28-day mortality was 0.86, higher than the AUC for SOFA (0.77), procalcitonin (0.73), lactate (0.67), IL-27 (0.65), and C-reactive protein (0.55). Patients with sepsis with higher admission levels of AIM (> 543.66 ng/mL) had significantly increased 28-day mortality compared with those with lower AIM levels (≤ 543.66 ng/mL). The association between admission levels of AIM and 28-day mortality was confirmed in the validation cohort of adult patients. In another cohort of pediatric patients with sepsis, the AUC for AIM level association with 28-day mortality was 0.82.

CONCLUSIONS

Circulating AIM levels at admission were markedly increased in patients with sepsis, which can serve as a novel prognostic biomarker for predicting mortality.

The usefulness of C-reactive protein and procalcitonin to predict prognosis in septic shock patients: A multicenter prospective registry-based observational study

The objective of this study was to evaluate the prognostic value of C-reactive protein (CRP), procalcitonin (PCT), and their combination for mortality in patients with septic shock. This multicenter, prospective, observational study was conducted between November 2015 and December 2017. A total of 1,772 septic shock patients were included, and the overall 28-day mortality was 20.7%. Although both CRP and PCT were elevated in the non-survivor group, only CRP had statistical significance (11.9 mg/dL vs. 14.7 mg/dL, p = 0.003, 6.4 ng/mL vs. 8.2 ng/mL, p = 0.508). Multivariate analysis showed that CRP and PCT were not independent prognostic markers. In the subgroup analysis of the CRP and PCT combination matrix using their optimal cut-off values (CRP 14.0 mg/dL, PCT 17.0 ng/dL), both CRP and PCT elevated showed significantly higher mortality (Odds ratio 1.552 [95% Confidence intervals 1.184-2.035]) than both CRP and PCT not elevated (p = 0.001) and only PCT elevated (p = 0.007). However, both CRP and PCT elevated was also not an independent predictor in multivariate analysis. Initial levels of CRP and PCT alone and their combinations in septic shock patients had a limitation to predict 28-day mortality. Future research is needed to determine new biomarkers for early prognostication in patients with septic shock.

Risk stratification and prognostic evaluation of endothelial cell-specific molecule1, von Willebrand factor, and a disintegrin-like and metalloprotease with thrombospondin type 1 motif for sepsis in the emergency department: An observational study

This study evaluated endothelial cell-specific molecule1 (endocan), von Willebrand factor (vWF), and A disintegrin-like and metalloprotease with thrombospondin type 1 motif (ADAMTS-13), alone or in combination, in the risk stratification and prognosis prediction of patients with sepsis. Clinical data of 301 patients were prospectively analyzed, and divided into systemic inflammatory reaction syndrome, sepsis, severe sepsis, and septic shock groups. A total of 40 healthy individuals were studied as the control group. Endocan, vWF, ADAMTS-13, vWF/ADAMTS-13, and procalcitonin levels were measured, and Acute Physiology and Chronic Health Evaluation (APACHE II) score, Mortality in Emergency Department Sepsis (MEDS) score as well as Sequential Organ Failure Assessment (SOFA) score were calculated. The all-cause death or survival of each patient was recorded during the 28-day follow-up. The endocan, vWF, and vWF/ADAMTS-13 levels significantly increased in patients and were positively correlated with disease severity. On the first day of admission, MEDS score, ADAMTS-13, and vWF/AMAMTS-13 ratio were independent predictors for 28-day mortality from sepsis. Moreover, the combination of vWF/ADAMTS-13 ratio with MEDS score improved the accuracy in predicting the 28-day mortality from sepsis. On day 5, endocan, vWF, ADAMTS-13, and vWF/ADAMTS-13 ratio were independent predictors for the 28-day mortality from sepsis, while the combined use of endocan and vWF/ADAMTS-13 ratio improved the prognostic value of individual indicators. Endocan, vWF, ADAMTS-13, and vWF/ADAMTS-13 ratio are valuable in the risk stratification and prognostic evaluation of sepsis as novel biomarkers.

The Long Pentraxin PTX3 as a Humoral Innate Immunity Functional Player and Biomarker of Infections and Sepsis

The first line of defense in innate immunity is provided by cellular and humoral mediators. Pentraxins are a superfamily of phylogenetically conserved humoral mediators of innate immunity. PTX3, the first long pentraxin identified, is a soluble pattern recognition molecule rapidly produced by several cell types in response to primary pro-inflammatory signals and microbial recognition. PTX3 acts as an important mediator of innate immunity against pathogens of fungal, bacterial and viral origin, and as a regulator of inflammation, by modulating complement activation and cell extravasation, and facilitating pathogen recognition by myeloid cells. In sepsis, PTX3 plasma levels are associated with severity of the condition, patient survival, and response to therapy. In combination with other established biomarkers, PTX3 could improve stratification of sepsis patients and thus, complement the system of classification and monitoring of this disease.

Acute phase reactant serum amyloid A in inflammation and other diseases

Acute-phase reactant serum amyloid A (A-SAA) plays an important role in acute and chronic inflammation and is used in clinical laboratories as an indicator of inflammation. Although both A-SAA and C-reactive protein (CRP) are acute-phase proteins, the detection of A-SAA is more conclusive than the detection of CRP in patients with viral infections, severe acute pancreatitis, and rejection reactions to kidney transplants. A-SAA has greater clinical diagnostic value in patients who are immunosuppressed, patients with cystic fibrosis who are treated with corticoids, and preterm infants with late-onset sepsis. Nevertheless, for the assessment of the inflammation status and identification of viral infection in other pathologies, such as bacterial infections, the combinatorial use of A-SAA and other acute-phase proteins (APPs), such as CRP and procalcitonin (PCT), can provide more information and sensitivity than the use of any of these proteins alone, and the information generated is important in guiding antibiotic therapy. In addition, A-SAA-associated diseases and the diagnostic value of A-SAA are discussed. However, the relationship between different A-SAA isotypes and their human diseases are mostly derived from research laboratories with limited clinical samples. Thus, further clinical evaluations are necessary to confirm the clinical significance of each A-SAA isotype. Furthermore, the currently available A-SAA assays are based on polyclonal antibodies, which lack isotype specificity and are associated with many inflammatory diseases. Therefore, these assays are usually used in combination with other biomarkers in the clinic.

[Place of biomarkers in the management of pulmonary infections]

INTRODUCTION

The management of acute lower respiratory tract infections and, in particular, the decision whether or not to commence antibiotic therapy, still remains difficult in the absence of reliable clinical or radiological criteria allowing confident distinction between bacterial and viral infections. Numerous biomarkers have been developed to help the clinician in his/her diagnostic and therapeutic approach, but the role and significance of each has not been clearly defined.

BACKGROUND

Though procalcitonin (PCT) or C-reactive protein (CRP) seem equal in helping the clinician to decide whether to commence antibiotic therapy or not during the course of an exacerbation of asthma or chronic obstructive pulmonary disease (COPD), PCT is currently the most useful biomarker to distinguish sepsis from other causes of inflammation and to determine the bacterial or viral origin of a pneumonia.

OUTLOOK

The ability of PCT to reduce the global exposure to antibiotics remains uncertain and the results of randomised trials are contradictory.

CONCLUSIONS

Prescription algorithms involving PCT may be used without increased risk for patients even though clinical signs of severity remain important. Changes in PCT also have a prognostic value in identifying those patients with unfavourable outcome.

[Association of inflammatory indices with the severity of urinary sepsis: analysis of 70 cases]

OBJECTIVE

To analyze the association of the clinical inflammatory indices with the severity of urinary sepsis.

METHODS

We reviewed the clinical data of 70 patients with urinary sepsis treated in our hospital between January, 2013 and April, 2018. All the patients were diagnosed in line with the Guidelines for Diagnosis and Treatment of Urological Diseases in China (2014 edition), including 22 patients with sepsis, 12 with hypotension and severe sepsis, 17 with septic shock, and 19 with critical septic shock. White blood cell count (WBC), neutrophil percentage (N%), platelets (PLT), fibrinogen (FIB), Ddimer, interleukin-6 (IL-6), procalcitonin (PCT) and C-reactive protein (CRP) were examined in all the cases and compared among the 4 groups. The correlations of these inflammatory markers with the severity of sepsis were analyzed using logistic regression analysis.

RESULTS

The 4 groups of patients showed significant differences in N%, PLT, D-dimer, and PCT (P < 0.05) but not in CRP (P>0.05). Kruskal-Wallis Pairwise comparisons showed that the N% and PCT in patients with sepsis differed significantly from those in the other 3 groups; platelets in patients with sepsis differed significantly from those in patients with septic shock and critical septic shock; D-dimer differed significantly between patients with sepsis and those with septic shock. Among the 4 groups, the median levels of PLT decreased and PCT and N% increased with the worsening of sepsis. Logistic regression analysis indicated that PCT (r=0.186, P=0.000), N% (r=0.047, P=0.035) and PLT (r=-0.012, P=0.003) were significantly correlated with the severity of sepsis in these patients.

CONCLUSIONS

PCT, PLT and N% are all significantly correlated with the severity of sepsis, and their combined detection can be informative for assessing the severity of sepsis to facilitate clinical decisions on treatment.

Procalcitonin Is a Prognostic Marker of Hospital Outcomes in Patients with Critical Limb Ischemia and Diabetic Foot Infection

AIM

To evaluate the prognostic role of procalcitonin (PCT) in patients with diabetic foot infection (DFI) and critical limb ischemia (CLI).

MATERIALS AND METHODS

The study group was composed of diabetic patients with DFI and CLI. All patients were treated according to a preset limb salvage protocol which includes revascularization, wound debridement, antibiotic therapy, and offloading. Inflammatory markers, including PCT, were evaluated at admission. Only positive values of PCT, greater than 0.5 ng/ml, were considered. Hospital outcomes were categorized as limb salvage (discharge with preserved limb), major amputation (amputation above the ankle), and mortality.

RESULTS

Eighty-six patients were included. The mean age was 67.3 ± 11.4 years, 80.7% were male, 95.1% had type 2 diabetes, and the mean diabetes duration was 20.5 ± 11.1 with a mean HbA1c of 67 ± 16 mmol/mol. 66/86 (76.8%) of patients had limb salvage, 7/86 (8.1%) had major amputation, and 13/86 (15.1%) died. Patients with positive PCT baseline values in comparison to those with normal values showed a lower rate of limb salvage (30.4 versus 93.6%, p = 0.0001), a higher rate of major amputation (13 versus 6.3%, p = 0.3), and a higher rate of hospital mortality (56.5 versus 0%, p < 0.0001). At the multivariate analysis of independent predictors found at univariate analysis, positive PCT was an independent predictor of major amputation [OR 3.3 (CI 95% 2.0-5.3), p = 0.0001] and mortality [OR 4.1 (CI 95% 2.2-8.3), p < 0.0001].

DISCUSSION

Positive PCT at admission increased the risk of major amputation and mortality in hospital patients with DFI and CLI.

Prognostic Value of Serum Procalcitonin level for the Diagnosis of Bacterial Infections in Critically-ill Patients

Background

Procalcitonin (PCT) is a diagnostic biomarker for bacterial infections in critically-ill patients. However, the cut-off value of PCT for the diagnosis of bacterial infections is unclear and unreliable. This study aimed to determine the optimal cut-off value of PCT for the diagnosis of bacterial infections in critically-ill patients.

Materials and Methods

We conducted a retrospective study involving 311 adult patients who had been admitted to the medical or surgical intensive care unit for more than 24 hours from 2013 to 2015. At least one blood test for PCT level was performed for all patients within the first 24 hours of suspecting an infection.

Results

One hundred and fifty-seven patients had bacterial infections, while 154 did not. Patients with bacterial infections had a significantly higher median PCT level than those without bacterial infections (1.90 ng/mL vs. 0.16 ng/mL, P <0.001). The area under the receiver operating characteristic curve of PCT for discriminating between bacterial and non-bacterial infections was 0.874 (95% confidence interval: 0.834, 0.914; P <0.001). The optimal cut-off value of PCT for differentiating between fevers due to bacterial infections from those due to non-bacterial infections was 0.5 ng/mL, with a sensitivity of 84.7%, specificity of 79.9%, positive predictive value of 81.1%, and negative predictive value of 83.7%.

Conclusion

PCT was found to be an accurate biomarker for the diagnosis of bacterial infections among patients admitted to medical and surgical intensive care units. The optimal cut-off value of PCT for the diagnosis of bacterial infections was 0.5 ng/mL.

Undifferentiated Shock and Extreme Elevation of Procalcitonin Related to Kratom Use

An 18-year-old male with history of polysubstance abuse presented to the emergency department with intractable vomiting, diarrhea, and abdominal pain for one day after the consumption of kratom. Examination revealed arterial hypotension, tachycardia, and prolonged capillary refill. Laboratory studies showed white blood cell count (WBC) of 23.6 × 109/L, serum creatinine 4.0 mg/dL, lactate 6 mmol/L, and procalcitonin >200 ng/mL. Urine and blood drug screen were unremarkable. Radiology and echocardiogram were noncontributory. He received fluid resuscitation and broad spectrum antibiotics. Vasopressors were subsequently added to manage persistent shock. He remained afebrile, and his blood cultures were negative. His shock and associated organ dysfunctions improved over the next 72 hours. On discharge, his procalcitonin level decreased to 9.55 ng/mL, leukocytosis resolved, and the creatinine returned to baseline. This case describes an extremely rare presentation related to kratom, an herb marketed as an opioid alternative, with significant potential for addiction and withdrawal syndrome.

How to cite this article: Zuberi M, Guru PK, Bansal V, Diaz-Gomez J, Grieninger B, Alejos D. Undifferentiated Shock and Extreme Elevation of Procalcitonin Related to Kratom Use. Indian J Crit Care Med 2019;23(5):239–241.

Serum folic acid, PCT, CRP and ESR detection as biomarker in differentiation ulcerative colitis activity

Objective: To investigate the serum concentration of folic acid, procalcitonin (PCT), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) as biomarkers in the differentiation of the severity of ulcerative colitis (UC). Methods: Fifty one patients who had been diagnosed with UC were recruited from January 2014 to August 2017. Twenty-two of these patients had severe diseases while the remaining twenty-nine patients had mild/moderate disease, according to the Truelove-Witts classification criteria. In the same study, 26 healthy subjects which served as the healthy controls were included alongside the UC patient group. The serum folic acid, PCT, CRP and ESR were examined and compared among the healthy control, mild/moderate and severe UC groups. Results: The serum PCT, CRP and ESR in the control group were significantly lower than those of mild/moderate and severe UC groups with statistical significance (p<0.001). However, the serum folic acid in the control group was significant higher than that of mild/ moderate and severe UC groups (p<0.001). The serum folic acid (p=0.015), PCT (p<0.001) and ESR (p<0.001) were significantly different between the severe and mild/moderate groups. However, the serum CRP was not statistically significant between the mild/moderate and severe UC groups (p=0.06). Using serum folic acid, PCT, CRP and ESR as biomarkers in the differentiation of mild/moderate and severe UC, the serum PCT had good diagnostic accuracy for detecting severe UC with the diagnostic sensitivity and specificity of 85.71% (63.66~96.95%), 82.76% (64.23~94.15%), respectively under the cut off value of 0.045. The correlation between serum CRP, ESR and PCT were examined by Pearson correlation test and line regression analysis. However, there was no correlation between each of them with the exception of folic acid and ESR (r=-0.334, p=0.017). Conclusion: Serum folic acid, PCT, CRP and ESR are significantly elevated in patients with active UC thereby presenting novel and potentially promising biomarkers for the diagnosis and differentiation of mild/moderate and sever UC.

Factors Predicting Bacterial Infection in Out-of-Hospital Cardiac Arrest Patients Undergoing Targeted Temperature Management

The objective of this study was to determine a risk factor for predicting bacterial infection in patients, who survived out-of-hospital cardiac arrest (OHCA), during targeted temperature management (TTM). This prospective registry-based retrospective observational study was conducted from November 2010 to October 2017. We measured several biomarkers such as whole blood cell counts, and levels of C-reactive protein and procalcitonin daily during TTM. The primary outcome was bacterial growth in initial blood or sputum cultures. A total of 116 patients were analyzed in this study. The bacterial growth rate was 32.8% and the procalcitonin levels measured at 24 h from cardiac arrest was significantly higher in the culture-positive group than the culture-negative group (10.6 vs. 2.5 ng/mL, p = 0.017). Area under the receiver operating characteristic curve for procalcitonin obtained after 24 h was 0.727 and the cutoff value was 6.5 ng/mL (odds ratio 9.58 [95% confidential interval, CI 2.21-41.55], p = 0.003). Sensitivity was 71.4% [95% CI 41.9-91.6] and specificity was 79.3% [95% CI 60.3-92.0]. Procalcitonin measured at 24 h from cardiac arrest was associated with bacterial infection in OHCA patients undergoing TTM. Further prospective interventional studies are needed to validate these results.

Procalcitonin-Guided Antibiotic Therapy Reduces Antibiotic Use for Lower Respiratory Tract Infections in a United States Medical Center: Results of a Clinical Trial

Background

European trials using procalcitonin (PCT)-guided antibiotic therapy for patients with lower respiratory tract infections (LRTIs) have demonstrated significant reductions in antibiotic use without increasing adverse outcomes. Few studies have examined PCT for LRTIs in the United States.

Methods

In this study, we evaluated whether a PCT algorithm would reduce antibiotic exposure in patients with LRTI in a US hospital. We conducted a controlled pre-post trial comparing an intervention group of PCT-guided antibiotic therapy to a control group of usual care. Consecutive patients admitted to medicine services and receiving antibiotics for LRTI were enrolled in the intervention. Providers were encouraged to discontinue antibiotics according to a PCT algorithm. Control patients were similar patients admitted before the intervention.

Results

The primary endpoint was median antibiotic duration. Overall adverse outcomes at 30 days comprised death, transfer to an intensive care unit, antibiotic side effects, Clostridium difficile infection, disease-specific complications, and post-discharge antibiotic prescription for LRTI. One hundred seventy-four intervention patients and 200 controls were enrolled. Providers complied with the PCT algorithm in 75% of encounters. Procalcitonin-guided therapy reduced median antibiotic duration for pneumonia from 7 days to 6 (P = .045) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) from 4 days to 3 (P = .01). There was no difference in the rate of adverse outcomes in the PCT and control groups.

Conclusions

A PCT-guided algorithm safely reduced the duration of antibiotics for treating LRTI. Utilization of a PCT algorithm may aid antibiotic stewardship efforts.

This clinical trial was a single-center, controlled, pre-post study of PCT-guided antibiotic therapy for LRTI. The intervention (incorporation of PCT-guided algorithms) started on April 1, 2017: the preintervention (control group) comprised patients admitted from November 1, 2016 to April 16, 2017, and the postintervention group comprised patients admitted from April 17, 2017 to November 29, 2017 (Supplementary Figure 1). The study comprised patients admitted to the internal medicine services to a medical ward, the Medical Intensive Care Unit (MICU), the Cardiac Intensive Care Unit (CICU), or the Progressive Care Unit (PCU) “step down unit”. The registration data for the trails are in the ClinicalTrials.gov database, number NCT0310910.

Implementation of the Procalcitonin Assay in a Rural Hospital

Objective: Most positive studies in procalcitonin (PCT) utilization were done in large, tertiary medical centers. Furthermore, there is a paucity of data describing the implementation process. This article is the first to describe in detail the implementation process and initial outcomes after 6 months of PCT testing in a rural, 65-bed, primary hospital. Methods: Education before and during PCT implementation as well as facility rollout are described. Initial outcomes were assessed using a before and after quasi-experimental study design comparing 2 identical 6-month time periods: May to October 2016 and May to October 2017. Antibiotic consumption is described with days of therapy (DOT) per 1000 patient days (PD). Antimicrobial purchasing costs, admission rates, and length of stay (LOS) are also compared. Results: Antimicrobial consumption was variable with the greatest reduction at 6 months: 856 DOT/1000 PD before versus 576 DOT/1000 PD after (P < .0001). Admission rates and LOS were unaffected. There was no associated savings in antibiotic purchasing costs: $114 189.79 before and $139 829.26 after (difference +$25 639.47). Conclusion: Although implementation of PCT testing is feasible in a rural health care facility, after 6 months, it was associated with a marginal decrease in antibiotic consumption with no decrease in admission rates, LOS, or antibiotic cost savings.

Decision tree analysis in subarachnoid hemorrhage: prediction of outcome parameters during the course of aneurysmal subarachnoid hemorrhage using decision tree analysis

OBJECTIVEThe aim of this study was to create prediction models for outcome parameters by decision tree analysis based on clinical and laboratory data in patients with aneurysmal subarachnoid hemorrhage (aSAH).METHODSThe database consisted of clinical and laboratory parameters of 548 patients with aSAH who were admitted to the Neurocritical Care Unit, University Hospital Zurich. To examine the model performance, the cohort was randomly divided into a derivation cohort (60% [n = 329]; training data set) and a validation cohort (40% [n = 219]; test data set). The classification and regression tree prediction algorithm was applied to predict death, functional outcome, and ventriculoperitoneal (VP) shunt dependency. Chi-square automatic interaction detection was applied to predict delayed cerebral infarction on days 1, 3, and 7.RESULTSThe overall mortality was 18.4%. The accuracy of the decision tree models was good for survival on day 1 and favorable functional outcome at all time points, with a difference between the training and test data sets of < 5%. Prediction accuracy for survival on day 1 was 75.2%. The most important differentiating factor was the interleukin-6 (IL-6) level on day 1. Favorable functional outcome, defined as Glasgow Outcome Scale scores of 4 and 5, was observed in 68.6% of patients. Favorable functional outcome at all time points had a prediction accuracy of 71.1% in the training data set, with procalcitonin on day 1 being the most important differentiating factor at all time points. A total of 148 patients (27%) developed VP shunt dependency. The most important differentiating factor was hyperglycemia on admission.CONCLUSIONSThe multiple variable analysis capability of decision trees enables exploration of dependent variables in the context of multiple changing influences over the course of an illness. The decision tree currently generated increases awareness of the early systemic stress response, which is seemingly pertinent for prognostication.

Pathologic Difference between Sepsis and Bloodstream Infections

BACKGROUND

Sepsis, defined as life-threatening organ failure caused by a dysregulated host response to infection, is a major cause of morbidity and mortality in hospitalized patients. Understanding the features that distinguish sepsis from bloodstream infections (and other types of infection) can help clinicians appropriately and efficiently target their diagnostic workup and therapeutic interventions, especially early in the disease course.

CONTENT

In this review, sepsis and bloodstream infections are both defined, with a focus on recent changes in the sepsis definition. The molecular and cellular pathways involved in sepsis pathogenesis are described, including cytokines, the coagulation cascade, apoptosis, and mitochondrial dysfunction. Laboratory tests that have been evaluated for their utility in sepsis diagnosis are discussed.

SUMMARY

Sepsis is defined not only by the presence of an infection, but also by organ dysfunction from a dysregulated host response to that infection. Numerous pathways, including proinflammatory and antiinflammatory cytokines, the coagulation cascade, apoptosis, and mitochondrial dysfunction, help determine if a bloodstream infection (or any other infection) progresses to sepsis. Many biomarkers, including C-reactive protein, procalcitonin, and lactic acid have been evaluated for use in sepsis diagnosis, although none are routinely recommended for that purpose in current clinical practice. While some laboratory tests can help distinguish the 2, the presence of organ dysfunction is what separates sepsis from routine infections.

The use of procalcitonin in the determination of severity of sepsis, patient outcomes and infection characteristics

Objective

The primary objective of this study was to determine the correlation between procalcitonin values and illness severity by evaluating the degree of end organ dysfunction using the Sequential Organ Failure Assessment score, length of stay and the severity of sepsis (sepsis alone vs. septic shock), The hypothesis that procalcitonin values would be higher in sicker patients was formulated before data collection began. Secondary outcomes studied in relation to procalcitonin levels included infection characteristics such as the site of infection, microbial agent and dialysis dependent CKD.

Design

Unblinded retrospective cohort study. September 2014-December 2016.

Setting

364 patients with a diagnosis of sepsis or severe sepsis who were admitted to the general medical ward and ICU at Methodist Medical Center and Proctor Hospital in Peoria, Illinois, USA.

Results

This study demonstrates the following: Weak positive correlation between procalcitonin and SOFA score. Negligible correlation with length of stay. Higher values in patients who died than in patients who survived to discharge (p = 0.058). Sensitivity and specificity of procalcitonin for septic shock was 63 and 65% respectively. Sites typically infected by gram negative bacteria have higher procalcitonin values than sites infected by gram positive bacteria (p = 0.03). Higher procalcitonin in bacteremia than non-bacteremic infections (p = 0.004). Higher procalcitonin in dialysis-dependent CKD patients (p = 0.020).

Conclusions

Procalcitonin has a higher specificity for bacterial infections than other acute phase reactants. Although initial procalcitonin value may be helpful in the determination of illness severity, it is not always a reliable prognostic indicator and carries little significance as a standalone value. Procalcitonin values may be influenced by preexisting comorbid conditions such as chronic kidney disease, which are associated with higher procalcitonin values at baseline. Procalcitonin can provide invaluable information when viewed as one piece of a clinical puzzle, and is most powerful when the interpreting physician is aware of how values are influenced by the different clinical scenarios presented in this article.

Cost-effectiveness of procalcitonin testing to guide antibiotic treatment duration in critically ill patients: results from a randomised controlled multicentre trial in the Netherlands

BACKGROUND

Procalcitonin (PCT) testing can help in safely reducing antibiotic treatment duration in intensive care patients with sepsis. However, the cost-effectiveness of such PCT guidance is not yet known.

METHODS

A trial-based analysis was performed to estimate the cost-effectiveness of PCT guidance compared with standard of care (without PCT guidance). Patient-level data were used from the SAPS trial in which 1546 patients were randomised. This trial was performed in the Netherlands, which is a country with, on average, low antibiotic use and a short duration of hospital stay. As quality of life among sepsis survivors was not measured during the SAPS, this was derived from a Dutch follow-up study. Outcome measures were (1) incremental direct hospital cost and (2) incremental cost per quality-adjusted life year (QALY) gained from a healthcare perspective over a one-year time horizon. Uncertainty in outcomes was assessed with bootstrapping.

RESULTS

Mean in-hospital costs were €46,081/patient in the PCT group compared with €46,146/patient with standard of care (i.e. - €65 (95% CI - €6314 to €6107); - 0.1%). The duration of the first course of antibiotic treatment was lower in the PCT group with 6.9 vs. 8.2 days (i.e. - 1.2 days (95% CI - 1.9 to - 0.4), - 14.8%). This was accompanied by lower in-hospital mortality of 21.8% vs. 29.8% (absolute decrease 7.9% (95% CI - 13.9% to - 1.8%), relative decrease 26.6%), resulting in an increase in mean QALYs/patient from 0.47 to 0.52 (i.e. + 0.05 (95% CI 0.00 to 0.10); + 10.1%). However, owing to high costs among sepsis survivors, healthcare costs over a one-year time horizon were €73,665/patient in the PCT group compared with €70,961/patient with standard of care (i.e. + €2704 (95% CI - €4495 to €10,005), + 3.8%), resulting in an incremental cost-effectiveness ratio of €57,402/QALY gained. Within this time frame, the probability of PCT guidance being cost-effective was 64% at a willingness-to-pay threshold of €80,000/QALY.

CONCLUSIONS

Although the impact of PCT guidance on total healthcare-related costs during the initial hospitalisation episode is likely negligible, the lower in-hospital mortality may lead to a non-significant increase in costs over a one-year time horizon. However, since uncertainty remains, it is recommended to investigate the long-term cost-effectiveness of PCT guidance, from a societal perspective, in different countries and settings.

[New Sepsis-3 definition : Do we have to treat sepsis before we can diagnose it from now on?]

The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) have been available since the beginning of 2016. SEPSIS-3 completely replaces the old SIRS criteria in the definition of sepsis and defines sepsis from now on as "life-threatening organ dysfunction caused by a dysregulated host response to infection". However, it seems questionable whether in clinical practice the new definition is really superior to the old one. The most important question is the following: Is it helpful to have a definition that first recognizes a patient once organ dysfunction has occurred and the patient already needs intensive care?

Biological variation of procalcitonin levels in hemodialysis patients

BACKGROUND

There is no obvious evidence regarding biological variation of procalcitonin (PCT) levels in hemodialysis (HD) patients without infections. The aim of this study was to determine the within- and between-person biological variation of PCT levels in HD patients without infections.

METHODS

A multicenter, prospective, cohort study enrolled 123 HD patients without any signs of infectious disease. Baseline PCT levels were determined pre- and post-HD, and then repeated pre-HD PCT measurements were performed at 2, 4, 8, 12, 16, 20, and 24 weeks after baseline blood-sampling, regardless of the presence or absence of infectious disease. Analytical variation (CVa), the within-person biological variation (CVi), between-person biological variation (CVb), individual index (II), and the reference change value (RCV) were calculated.

RESULTS

The mean age was 62.4 years, 76.4% were male, and 32.5% had diabetes. The mean duration of HD was 87 months. The median value for baseline pre-HD PCT was 0.23 ng/mL, which is much higher than the reference level for healthy individuals. PCT levels decreased of 46.6% after a single HD session. CVi was 24.9%, CVb was 54.2%, II was 0.46, and RCV was calculated as 96.4% with 99% probability.

CONCLUSIONS

The PCT level was significantly higher in stable HD patients without manifest bacterial infection. CVb was more variable than CVi in HD patients, which indicates that relative change is more important than absolute PCT levels for diagnosing bacterial infection, and doubling or more of the baseline PCT level may imply the presence of a bacterial infection in HD patients.

Increased procalcitonin level is a risk factor for prolonged fever in children with Mycoplasma pneumonia

PURPOSE

Macrolide-resistant Mycoplasma pneumoniae pneumonia (MPP) is characterized by prolonged fever and radiological progression despite macrolide treatment. Few studies have examined serum procalcitonin (PCT) level in children with MPP. We aimed to investigate the association of acute inflammation markers including PCT with clinical parameters in children with MPP.

METHODS

A total of 147 children were recruited. The diagnosis of MPP relied on serial measurement of IgM antibody against mycoplasma and/or polymerase chain reaction. We evaluated the relationships between C-reactive protein (CRP), PCT, and lactate dehydrogenase (LDH) levels and white blood cell (WBC) counts, and clinical severity of the disease. We used multivariate logistic regression analysis to estimate the odds ratio for prolonged fever (>3 days after admission) and hospital stay (> 6 days), comparing quintiles 2-5 of the PCT levels with the lowest quintile.

RESULTS

The serum PCT and CRP levels were higher in children with fever and hospital stay than in those with fever lasting ≤ 3 days after admission and hospital stay ≤ 6 days. CRP level was higher in segmental/lobar pneumonia than in bronchopneumonia. The LDH level and WBC counts were higher in children with fever lasting for >3 days before compared to those with fever lasting for ≤ 3 days. The highest quintile of PCT levels was associated with a significantly higher risk of prolonged fever and/or hospital stay than the lowest quintile.

CONCLUSION

Serum PCT and CRP levels on admission day were associated with persistent fever and longer hospitalization in children with MPP.

Is Procalcitonin Useful in Pediatric Critical Care Patients?

This review examines the use of procalcitonin in different clinical situations in the pediatric patient, with special emphasis on those requiring intensive care. We review the latest articles on its potency as a biomarker in both infectious processes at diagnosis and on the response to treatment.

Interleukin-17 as a predictor of sepsis in polytrauma patients: a prospective cohort study

Sepsis is one of the most serious complications after major trauma, and may be associated with increased mortality. We sought to determine whether there is an association between serum levels of interleukin-17 (IL-17) at the time of admission to the intensive care unit (ICU) and the development of sepsis. We evaluated 100 adult patients with major trauma admitted to the surgical ICU over a 6-month period. Serum levels of IL-17, IL-6, and TNF-α were determined by enzyme-linked immunosorbent assays (ELISA). The IL-17 rs1974226 genotype was determined by real-time PCR. In both non-adjusted and adjusted analyses, IL-17 was the only biomarker significantly associated with sepsis [median serum IL-17 of 72 pg/mL in sepsis versus 37 pg/mL in those without sepsis, P = 0.0001; adjusted odds ratio (OR) 3.2, P = 0.02]. No significant association was found among IL-17 rs1974226 genotypes and related serum cytokine levels. These data suggest that elevated serum IL-17 may increase the susceptibility for septic complications in polytrauma patients and so could be a useful biomarker for trauma patient management.

Sepsis Diagnostics in the Era of "Omics" Technologies

Sepsis is a multifactorial clinical syndrome with an extremely dynamic clinical course and with high diverse clinical phenotype. Early diagnosis is crucial for the final clinical outcome. Previous studies have not identified a biomarker for the diagnosis of sepsis which would have sufficient sensitivity and specificity. Identification of the infectious agents or the use of molecular biology, next gene sequencing, has not brought significant benefit for the patient in terms of early diagnosis. Therefore, we are currently searching for biomarkers, through "omics" technologies with sufficient diagnostic specificity and sensitivity, able to predict the clinical course of the disease and the patient response to therapy. Current progress in the use of systems biology technologies brings us hope that by using big data from clinical trials such biomarkers will be found.

Longitudinal Evaluation of Plasma Concentrations of Presepsin in Patients after Severe Trauma: A Prospective Observational Study

BACKGROUND

The high mortality rate of patients suffering from severe trauma is based not only on the mechanism of injury, but also on the higher risk for development of subsequent infections. Therefore, the early recognition of infection after severe trauma is of particular importance for patient outcome. However, early diagnosis is often masked by the consequences of the sterile, damage-triggered immune response. Our study sought to analyze the course of soluble CD14-subtype (sCD14-ST, presepsin) compared with clinically established inflammatory and infectious biomarkers in a cohort of patients with severe trauma.

PATIENTS AND METHODS

Between January 2015 and February 2016, 50 patients suffering from severe trauma (Injury Severity Score [ISS] > 16) were enrolled and followed up for seven consecutive days after intensive care unit (ICU) admission. Clinical routine data, signs of infection, and the inflammatory biomarkers presepsin, C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6) were assessed.

RESULTS

Regarding the well-established biomarkers CRP, PCT, and IL-6, we observed trauma-associated alterations (day 1: CRP 13 mg/L, interquartile range [IQR] 0-129; PCT 1.1 μg/L, IQR 0-13; IL-6 108 pg/mL, IQR 29-795), which did not correlate with the clinical development of systemic inflammatory response syndrome (SIRS), whereas elevated plasma concentrations of presepsin in the clinical course were associated with the presence of SIRS (presepsin: no-SIRS vs. SIRS p = 0.03).

CONCLUSION

Our study investigates systematically the kinetic of presepsin compared with established inflammatory and infectious markers after severe trauma. Presepsin is neither affected by the early post-traumatic nor the delayed immune response over seven days after trauma, making it a possible option as a diagnostic biomarker of infection worth further evaluation.

Value of procalcitonin for diagnosing perioperative pneumonia, urinary infections and superficial surgical site infections in patients undergoing primary hip and knee arthroplasty

Serum procalcitonin (PCT) levels may be helpful for the diagnosis of infections during the perioperative period of arthroplasty. However, there is much debate in the literature regarding the appropriate cut-off value for different types of surgery and local bacterial infection. The present study aimed to evaluate serum PCT levels in patients undergoing arthroplasty and to determine the cut-off value that may represent perioperative pneumonia, urinary infections and superficial surgical site infections. The present retrospective study included a total of 500 patients treated between July 2014 and August 2015. The case group contained 25 patients with perioperative infections (pneumonia, urinary and superficial surgical site infections), and the control group contained 25 patients without any post-surgical complications. Serum levels of PCT and white blood cells (WBC) were measured pre-operatively (D0) and at post-operative D4, D6 and D8, and the sensitivity, specificity and predictive value of these parameters were assessed. Regarding the comparison of the mean PCT levels between the case and the control group, a significant difference was seen at D8 (P=0.007), while no significant differences were observed at D0 (P=0.010), D4 (P=0.069) and D6 (P=0.093). No statistically significant differences in WBC levels between groups were observed for (P>0.01). In the control group, the PCT levels at D4 (0.062±0.020 ng/ml) were 2-fold of the mean baseline value, followed by a decrease until D6 (0.051±0.019 ng/ml) and a return close to the normal range by D8 (0.032±0.015 ng/ml). The PCT levels in the case group had rapidly increased on D4 (0.510±1.208 ng/ml). In contrast to the control group, they continuously increased on D6 (0.527±1.360 ng/ml) and D8 (0.686±1.117 ng/ml). From a clinical point of view, infection events were indicated in these patients during post-operative follow-up. For PCT, the area under the receiver operating characteristic curve (AUC) was 0.978 [95% confidence interval (CI), 0.933-1.022], and for WBC, the AUC was 0.562 (95% CI, 0.398-0.0.726). Based on the above data, the PCT value was a significant predictor of infection (AUC>0.9). For PCT, the cut-off point of 0.0995 ng/ml was associated with a sensitivity of 96% and a specificity of 100%. However, WBC were not a significant predictor of infection (0.5<AUC<0.7), and the cut-off value of 7.05×10⁹/l was associated with a sensitivity of 64% and a specificity of 44%. In conclusion PCT was found to be a promising marker for diagnosing bacterial infections post-arthroplasty due to its high specificity. Based on the sensitivity and the specificity, detecting PCT may be more valuable than using WBC in the diagnosis of sepsis-associated pathological changes in the perioperative period.

Procalcitonin measurement to screen medullary thyroid carcinoma: A prospective evaluation in a series of 2705 patients with thyroid nodules

BACKGROUND

To prospectively evaluate the role of procalcitonin (PCT) in screening of patients with thyroid nodules for medullary thyroid carcinoma (MTC).

MATERIALS AND METHODS

We measured PCT in 2705 patients with thyroid nodules referred to our centre between January 2011 and December 2017. Those with a positive PCT were operated after positive confirmatory tests such as fine-needle aspiration, measurement of calcitonin (CT) in serum and fine-needle aspiration washouts or CT stimulation testing. Patients with a negative PCT were operated based on the results of further diagnostics. The diagnostic performance of PCT was evaluated, and the best cut-off level was selected by ROC curve analysis.

RESULTS

Among 2705 patients, 9 with positive serum PCT (ie, above 0.1 μg/L) and 370 with negative PCT underwent thyroid surgery. MTC was histologically confirmed in all patients with positive PCT but not found in patients with negative PCT. Serum PCT levels were significantly higher in patients with MTC (median 0.64 μg/L, range 0.16-12.9 μg/L) than in those without (median 0.075 μg/L, range 0.075-0.16 μg/L; P < .0001). ROC curves were plotted to calculate the optimal PCT value separating patients with MTC from those without. The best cut-off was 0.155 μg/L with sensitivity, specificity, positive and negative predictive values as well as accuracy of 100%, 99.7%, 91.7%, 100% and 99.7%, respectively. Positive and negative likelihood ratios were 329 and zero, respectively.

CONCLUSIONS

Measurement of PCT is a sensitive and accurate method for detecting MTC in patients with thyroid nodules and can thus be a reliable alternative to CT measurement.

Role of Procalcitonin in the Management of Infected Patients in the Intensive Care Unit

The combination of molecular pathogen diagnostics and the biomarker procalcitonin (PCT) are changing the use of antimicrobials in patients admitted to critical care units with severe community-acquired pneumonia, possible septic shock, or other clinical syndromes. An elevated serum PCT level is good supportive evidence of a bacterial pneumonia, whereas a low serum PCT level virtually eliminates an etiologic role for bacteria even if the culture for a potential bacterial pathogen is positive. Serum PCT levels can be increased in any shocklike state; a low PCT level eliminates invasive bacterial infection as an etiology in more than 90% of patients.

Evaluation of the Use of Novel Biomarkers to Augment Antimicrobial Stewardship Program Activities

As antimicrobial stewardship increasingly receives worldwide attention for improving patient care by optimizing antimicrobial therapy, programs are evaluating new tools that may augment antimicrobial stewardship activities. Biomarkers are objective, accurate, and reproducible measures that provide information about medical conditions. A systematic literature search using PubMed/MEDLINE databases was performed to evaluate the use of novel biomarkers as additions to the antimicrobial stewardship armamentarium. Procalcitonin may help clinicians discriminate between bacterial and viral infections, help with antimicrobial discontinuation decisions, and predict mortality. β-d-glucan, Candida albicans germ tube antibody, and galactomannan are useful in suspected fungal infections and may reduce inappropriate antifungal use. Adrenomedullin and soluble triggering receptor on myeloid cells-1 may be useful for mortality prediction and the determination of a need for empiric antibacterials. Although studies evaluating these biomarkers are promising, these biomarkers are not without limitations and should be used in combination with clinical signs, symptoms, or other biomarkers. For successful implementation of biomarker use, stewardship programs should consider the populations most likely to benefit, without using them indiscriminately in all patients. Antimicrobial stewardship programs should facilitate education of clinicians through institutional guidelines to ensure the appropriate use and interpretation of these biomarkers.

Serum biomarkers in periprosthetic joint infections

OBJECTIVES

The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI.

METHODS

We searched two literature databases, using terms that encompass all hip and knee arthroplasty procedures, as well as PJI and statistical terms reflecting diagnostic parameters. The findings are summarized as a narrative review.

RESULTS

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were the two most commonly published serum biomarkers. Most evidence did not identify other serum biomarkers that are clearly superior to ESR and CRP. Other serum biomarkers have not demonstrated superior sensitivity and have failed to replace CRP and ESR as first-line screening tests. D-dimer appears to be a promising biomarker, but more research is necessary. Factors that influence serum biomarkers include temporal trends, stage of revision, and implant-related factors (metallosis).

CONCLUSION

Our review helped to identify factors that can influence serum biomarkers' level changes; the recognition of such factors can help improve their diagnostic utility. As such, we cannot rely on ESR and CRP alone for the diagnosis of PJI prior to second-stage reimplantation, or in metal-on-metal or corrosion cases. The future of serum biomarkers will likely shift towards using genomics and proteomics to identify proteins transcribed via messenger RNA in response to infection and sepsis.Cite this article:Bone Joint Res 2018;7:85-93.

Role of Single Procalcitonin Test on Admission as a Biomarker for Predicting the Severity of Clostridium difficile Infection

Objective: To evaluate whether serum Procalcitonin (PCT) at the early stage of infection can serve as a potential biomarker for determining Clostridium difficile infection (CDI) severity.

Methods: Fifty-four patients diagnosed with CDI were enrolled in the study. Serum samples were obtained within a median time of 24–48 h of the lab result for presence of C. difficile. PCT levels were measured by chemiluminescence immunoassay. Demographic, clinical, and prognostic data concerning the patients were retrospectively collected from medical records. The illness severity score was determined according to “Score indices for C. difficile infection severity.”

Results: We found that serum PCT levels were significantly higher in patients with moderate disease, compared to patients with mild disease (p = 0.0032). Additionally, PCT was correlated with mortality (p = 0.0002), white blood cell count (p = 0.019), and community-acquired disease (p = 0.0345).

Conclusion: Early measurement of PCT may serve as a biomarker for early prediction of CDI severity, which is of great importance due to the high risk of complications and death.

Procalcitonin: The marker of pediatric bacterial infection

Timely recognition of systemic bacterial infections in pediatric care setting is the basis for effective treatment and control. This review provides an overview of procalcitonin (PCT) as an early marker for the detection of severe, invasive bacterial infection in children. Almost all articles on biochemical property and clinical studies in PubMed and Scopus databases regarding their use in pediatric infections and the use of PCT as a marker of bacterial infections were examined. Various methods and analyzers are currently available for the evaluation of PCT. Employment of PCT in the identification of neonatal bacterial infection is a complex process in some conditions. Age specific cut-off, underlying syndrome, and maternal antibiotics usage should be considered when PCT is to be applied in neonates. PCT might be false-negative in these conditions. However, if used appropriately, it can lead to a higher specificity than other immunologic markers. Due to its correlation with the severity of infection, PCT can consequently be used as a prognostic indicator especially for sepsis and urinary tract infection. It is, therefore, a practical supplementary means for the identification of bacterial infections in pediatric health settings.