Procalcitonin in sepsis and systemic inflammation: a harmful biomarker and a therapeutic target

Procalcitonin, brain natriuretic peptide and albumin as markers to predict prognosis in hospitalized older Japanese patients with a risk of infection

AIM

Whether serum concentration of procalcitonin (PCT), brain natriuretic peptide (BNP) and albumin (Alb) have an association with the outcome of hospitalized older patients is unclear. We investigated clinical outcomes and any predictive factors in hospitalized Japanese older patients with a risk of infection.

METHODS

In the retrospective study, 820 Japanese patients were followed up for 30 days or until death. During the observation period, 656 patients survived and 164 patients died. The predictive factors of death were analyzed according to demographic and clinical variables.

RESULTS

The survival rate was decreased as the serum PCT increased from <0.5 to ≥10 ng/mL, as was also the case with BNP from <300 to ≥300 pg./mL, whereas low Alb (<2.5 g/dL) showed a lower survival rate than high Alb (≥2.5 g/dL; P < 0.01). Using the Cox regression model, the multivariable-adjusted hazard ratios (95% confidence interval) were as follows: PCT 0.5-2 versus <0.5 ng/mL: 1.61(1.04-2.49), PCT 2-10 versus <0.5 ng/mL: 1.91(1.15-3.16), PCT ≥10 versus <0.5 ng/mL: 2.90(1.84-4.59), high BNP 1.26 (0.89-1.76) and low Alb 0.68 (0.52-0.87). The mortality rate increased as the number of scores (PCT + BNP + Alb) increased.

CONCLUSIONS

Concentration-dependent high PCT, high BNP and low Alb were positive risk factors associated with poor prognosis in hospitalized older patients with a risk of infection. Geriatr Gerontol Int 2024; 24: 571-576.

Improved diagnostic markers for invasive pulmonary aspergillosis in COPD patients

Background

The prevalence of invasive pulmonary aspergillosis (IPA) among patients with chronic obstructive pulmonary disease (COPD) is steadily increasing, leading to high mortality. Although early diagnosis can significantly reduce mortality, the efficacy of current diagnostic methods is limited. Consequently, there is a need for novel approaches for early IPA detection.

Methods

This retrospective study involved 383 hospitalized COPD patients with GOLD stages III and IV. The IPA group (67 patients) and non-IPA group (316 patients) were identified at the First Affiliated Hospital of Guangzhou Medical University between January 2016 and February 2022. We analyzed common serological indicators in our hospital to identify predictive indicators for the early diagnosis of IPA in COPD patients.

Results

The sensitivity and specificity of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), lactate dehydrogenase (LDH), and ceruloplasmin (CER) for diagnosing IPA in COPD patients were as follows: CRP (91.2%, 57.7%), ESR (77.5%, 73.0%), PCT (60.5%, 71.4%), LDH (50.0%, 88.8%), and CER (60.7%, 74.3%). Combinations of biomarkers, such as CRP-ESR, CRP-LDH, ESR-LDH, ESR-CER, and LDH-CER, showed promising diagnostic potential, with larger area under the curve (AUC) values for IPA diagnosis in COPD patients. However, no statistically significant difference was observed between the diagnostic efficacy of single biomarkers and combined biomarkers. Notably, compared to those in the unassisted ventilation group, the patients in the assisted ventilation group (including noninvasive ventilation and tracheal intubation/incision-assisted ventilation group) exhibited significantly greater PCT and LDH levels, while the CER significantly decreased (p=0.021). There were no significant differences in biomarker levels between the ICU group and the non-ICU group. CRP (p<0.01), ESR (p=0.028), PCT (p<0.01), and CER (p<0.01) were positively correlated with hospitalization duration, whereas LDH was not correlated with hospitalization duration.

Conclusion

Our study highlights the diagnostic potential of CRP, ESR, PCT, LDH, and CER for IPA in COPD patients. CRP and LDH can also initially predict the need for assisted ventilation, while CRP can initially estimate the length of hospitalization. This study represents the first report of the potential of CER for diagnosing IPA, suggesting its significance for further research.

Efficient expression and purification of tag-free recombinant human procalcitonin (hPCT) with precise sequence in E.coli

We present an efficient method for expression and purification of recombinant human procalcitonin (hPCT) in E. coli T7 express LysY/Iq cells, ensuring precise N- and C-terminal amino acid sequences. Our method involves fusing codon-optimized cDNA with two distinct tag sequences: eXact tag and chitin binding domain (CBD) tag. To purify the protein, we employ a two-step affinity chromatography process. Firstly, we utilize the N-terminal Profinity eXact tag and purify the protein through Profinity eXact-affinity column chromatography using a resin on which a mutant subtilisin protease was immobilized. The eXact tag was removed by adding NaF to activate the enzyme. Subsequently, the digested sample containing C-terminal CBD tag is directly loaded for the second step of chitin affinity chromatography. Elution is achieved through dithiothreitol (DTT)-catalyzed self-cleavage of the intein sequence from the fusion protein. As a result, the target protein is selectively recovered in the flow-through, completely tag-free, with a purity exceeding 95%. To ensure high purity and eliminate potential contaminants, we effectively remove E. coli host DNA and endotoxins through a combination of streptomycin sulfate, Triton X-114, and ammonium sulfate treatment. The exceptional level of purity obtained eliminates the need for further purification steps in most applications. This highly purified hPCT can be used as a calibrator in procalcitonin or calcitonin immunoassays. Notably, our approach effectively manages small peptides that are prone to degradation by E. coli host proteases, offering a robust solution for various research and application requirements.

The value of age IgG and IL6 in estimating time of viral clearance in asymptomatic or mild patients with COVID-19

Background

The aim of this study was to investigate the relationship between Age, immunoglobin G (IgG), immunoglobin M (IgM), procalcitonin (PCT), and interleukin-6 (IL6), and the time to clear viral nucleic acids in asymptomatic and mild coronavirus disease 2019 (COVID-19) patients, as well as evaluated the predictive value of these biochemical indicators.

Methods

We performed a retrospective analysis on 1,570 individuals who were admitted to Tianjin First Central Hospital and diagnosed with asymptomatic or mild cases. Laboratory data were collected, including age, gender, levels of IgG, IgM, PCT and IL6, as well as results of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) nucleic acid test. These data were statistically analyzed using SPSS software, version 24.0.

Results

The results indicated that among mild patients, Age, IgG, and the time to clear viral nucleic acids were higher than asymptomatic patients (p < 0.05). And the time to clear viral nucleic acids was significantly correlated with Age, IgG, IgM, PCT, and IL6 (p < 0.05), IgG (r = -0.445, p < 0.001) showed moderate correlations. Using logistic regression analysis, we identified older age, high IL6 levels, and low IgG levels were risk factors for nucleic acid clearance exceeding 14 days (p < 0.05). When combining these three indicators to predict the probability of nucleic acid clearance exceeding 14 days in the 1,570 patients, the AUROC was found to be 0.727.

Conclusion

Age, IgG, and IL6 could potentially serve as useful predictors for nucleic acid clearance exceeding 14 days in asymptomatic and mild COVID-19 patients.

Severe Acute Pancreatitis Prediction: A Model Derived From a Prospective Registry Cohort

Background Severe acute pancreatitis (SAP) has a mortality rate as high as 40%. Early identification of SAP is required to appropriately triage and direct initial therapies. The purpose of this study was to develop a prognostic model that identifies patients at risk for developing SAP of patients managed according to a guideline-based standardized early medical management (EMM) protocol. Methods This single-center study included all patients diagnosed with acute pancreatitis (AP) and managed with the EMM protocol Methodist Acute Pancreatitis Protocol (MAPP) between April 2017 and September 2022. Classification and regression tree (CART®; Professional Extended Edition, version 8.0; Salford Systems, San Diego, CA), univariate, and logistic regression analyses were performed to develop a scoring system for AP severity prediction. The accuracy of the scoring system was measured by the area under the receiver operating characteristic curve. Results A total of 516 patients with mild (n=436) or moderately severe and severe (n=80) AP were analyzed. CART analysis identified the cutoff values: creatinine (CR) (1.15 mg/dL), white blood cells (WBC) (10.5 × 109/L), procalcitonin (PCT) (0.155 ng/mL), and systemic inflammatory response system (SIRS). The prediction model was built with a multivariable logistic regression analysis, which identified CR, WBC, PCT, and SIRS as the main predictors of severity. When CR and only one other predictor value (WBC, PCT, or SIRS) met thresholds, then the probability of predicting SAP was >30%. The probability of predicting SAP was 72% (95%CI: 0.59-0.82) if all four of the main predictors were greater than the cutoff values. Conclusions Baseline laboratory cutoff values were identified and a logistic regression-based prognostic model was developed to identify patients treated with a standardized EMM who were at risk for SAP.

Comparison of Prognostic Performance between Procalcitonin and Procalcitonin-to-Albumin Ratio in Post Cardiac Arrest Syndrome

(1) Background: Post-cardiac arrest syndrome (PCAS) is a type of global ischemic reperfusion injury that occurs after the return of spontaneous circulation (ROSC). The procalcitonin to albumin ratio (PAR) has been studied as an independent prognostic factor of various diseases. There are no previous studies of PAR in patients with PCAS. We assessed if PAR is more effective than procalcitonin (PCT) in predicting prognosis for patients with PCAS. (2) Methods: This retrospective cohort study included a total of 187 patients with PCAS after non-traumatic out-of-hospital cardiac arrest (OHCA) between January 2016 and December 2020. Multivariate logistic regression analysis was conducted to assess the association between PAR and PCAS prognosis. The predictive performance of PAR was compared with PCT via the receiver-operating characteristic (ROC) analysis and DeLong test.; (3) Results: PAR at 24 and 48 h after hospital admission were independently associated with one-month neurological outcome (OR: 1.167, 95% CI: 1.023-1.330; OR: 1.077, 95% CI: 1.012-1.146, p < 0.05). By ROC analysis, PAR showed better performance over PCT at 48 h after admission in predicting one-month CPC (0.763 vs. 0.772, p = 0.010). (4) Conclusions: Our findings suggest that PAR at 48 h after admission is more effective in predicting a one-month neurological outcome than PCT at 48 h after admission in patients with PCAS after OHCA.

Procalcitonin as an Endogenous Biomarker for Mastitis in Cows

Mastitis is one of the most common diseases of dairy cows. Procalcitonin (PCT) has been described as an endogenous inflammatory biomarker for bacterial infections. The aim of this study was to find possible correlations between PCT concentrations in the serum and milk of cows with mastitis and their clinical signs and disease progression. In total, 88 dairy cows were examined, of which 30 animals were diagnosed with clinical mastitis, 30 had subclinical mastitis, and 28 were designated as a healthy control group. The diseased animals were re-examined after 12 days. All PCT levels in this study were determined by a species-specific ELISA. All three groups could be differentiated from each other based on serum and milk PCT levels. The animals with clinical mastitis showed the highest mean concentrations of PCT (serum: 2641 pg/mL; milk: 1326 pg/mL), and the lowest PCT concentrations were found in the healthy control group (serum: 1166 pg/mL; milk: 176 pg/m). Over the course of the disease, results from the kinetics study showed that PCT levels remained high for the entire observation period. The results from this study showed that the PCT concentration could be used to differentiate between clinical mastitis, subclinical mastitis, and healthy cows.

Aminoprocalcitonin protects against hippocampal neuronal death via preserving oxidative phosphorylation in refractory status epilepticus

Refractory status epilepticus (RSE) is a neurological emergency where sustaining seizure causes severe neuronal death. Currently, there is no available neuroprotectant effective in RSE. Aminoprocalcitonin (NPCT) is a conserved peptide cleaved from procalcitonin, but its distribution and function in the brain remain enigmatic. Survival of neurons relies on sufficient energy supply. Recently, we found that NPCT was extensively distributed in the brain and had potent modulations on neuronal oxidative phosphorylation (OXPHOS), suggesting that NPCT might be involved in neuronal death by regulating energy status. In the present study, combining biochemical and histological methods, high-throughput RNA-sequence, Seahorse XFe analyser, an array of mitochondria function assays, and behavior-electroencephalogram (EEG) monitoring, we investigated the roles and translational values of NPCT in neuronal death after RSE. We found that NPCT was extensively distributed throughout gray matters in rat brain while RSE triggered NPCT overexpression in hippocampal CA3 pyramidal neurons. High-throughput RNA-sequence demonstrated that the influences of NPCT on primary hippocampal neurons were enriched in OXPHOS. Further function assays verified that NPCT facilitated ATP production, enhanced the activities of mitochondrial respiratory chain complexes I, IV, V, and increased neuronal maximal respiration capacity. NPCT exerted multiple neurotrophic effects including facilitating synaptogenesis, neuritogenesis, spinogenesis, and suppression of caspase-3. A polyclonal NPCT immunoneutralization antibody was developed to antagonize NPCT. In the in vitro 0-Mg²⁺ seizure model, immunoneutralization of NPCT caused more neuronal death, while exogenous NPCT supplementation, though did not reverse death outcomes, preserved mitochondrial membrane potential. In rat RSE model, both peripheral and intracerebroventricular immunoneutralization of NPCT exacerbated hippocampal neuronal death and peripheral immunoneutralization increased mortality. Intracerebroventricular immunoneutralization of NPCT further led to more serious hippocampal ATP depletion, and significant EEG power exhaustion. We conclude that NPCT is a neuropeptide regulating neuronal OXPHOS. During RSE, NPCT was overexpressed to protect hippocampal neuronal survival via facilitating energy supply.

AACC Guidance Document on the Clinical Use of Procalcitonin

BACKGROUND

Procalcitonin (PCT), a peptide precursor of the hormone calcitonin, is a biomarker whose serum concentrations are elevated in response to systemic inflammation caused by bacterial infection and sepsis. Clinical adoption of PCT in the United States has only recently gained traction with an increasing number of Food and Drug Administration-approved assays and expanded indications for use. There is interest in the use of PCT as an outcomes predictor as well as an antibiotic stewardship tool. However, PCT has limitations in specificity, and conclusions surrounding its utility have been mixed. Further, there is a lack of consensus regarding appropriate timing of measurements and interpretation of results. There is also a lack of method harmonization for PCT assays, and questions remain regarding whether the same clinical decision points may be used across different methods.

CONTENT

This guidance document aims to address key questions related to the use of PCT to manage adult, pediatric, and neonatal patients with suspected sepsis and/or bacterial infections, particularly respiratory infections. The document explores the evidence for PCT utility for antimicrobial therapy decisions and outcomes prediction. Additionally, the document discusses analytical and preanalytical considerations for PCT analysis and confounding factors that may affect the interpretation of PCT results.

SUMMARY

While PCT has been studied widely in various clinical settings, there is considerable variability in study designs and study populations. Evidence to support the use of PCT to guide antibiotic cessation is compelling in the critically ill and in some lower respiratory tract infections but is lacking in other clinical scenarios, and evidence is also limited in the pediatric and neonatal populations. Interpretation of PCT results requires guidance from multidisciplinary care teams of clinicians, pharmacists, and clinical laboratorians.

Inactivation of the gene encoding procalcitonin prevents antibody-mediated arthritis

BACKGROUND

Procalcitonin (PCT) is applied as a sensitive biomarker to exclude bacterial infections in patients with rheumatoid arthritis (RA) flare-ups. Beyond its diagnostic value, little is known about the pathophysiological role of PCT in RA.

METHODS

Collagen antibody-induced arthritis (CAIA) was induced in Calca-deficient mice (Calca^-/-), lacking PCT (n = 15), and wild-type (WT) mice (n = 13), while control (CTRL) animals (n = 8 for each genotype) received phosphate-buffered saline. Arthritis severity and grip strength were assessed daily for 10 or 48 days. Articular inflammation, cartilage degradation, and bone lesions were assessed by histology, gene expression analysis, and µ-computed tomography.

RESULTS

Serum PCT levels and intra-articular PCT expression increased following CAIA induction. While WT animals developed a full arthritic phenotype, Calca-deficient mice were protected from clinical and histological signs of arthritis and grip strength was preserved. Cartilage turnover markers and Tnfa were exclusively elevated in WT mice. Calca-deficient animals expressed increased levels of Il1b. Decreased bone surface and increased subchondral bone porosity were observed in WT mice, while Calca-deficiency preserved bone integrity.

CONCLUSION

The inactivation of Calca and thereby PCT provided full protection from joint inflammation and arthritic bone loss in mice exposed to CAIA. Together with our previous findings on the pathophysiological function of Calca-derived peptides, these data indicate an independent pro-inflammatory role of PCT in RA.

Spontaneous Sepsis in Adult Horses: From Veterinary to Human Medicine Perspectives

Sepsis is a life-threatening disease defined as an organ dysfunction caused by a dysregulated host response to an infection. Early diagnosis and prognosis of sepsis are necessary for specific and timely treatment. However, no predictive biomarkers or therapeutic targets are available yet, mainly due to the lack of a pertinent model. A better understanding of the pathophysiological mechanisms associated with sepsis will allow for earlier and more appropriate management. For this purpose, experimental models of sepsis have been set up to decipher the progression and pathophysiology of human sepsis but also to identify new biomarkers or therapeutic targets. These experimental models, although imperfect, have mostly been performed on a murine model. However, due to the different pathophysiology of the species, the results obtained in these studies are difficult to transpose to humans. This underlines the importance of identifying pertinent situations to improve patient care. As humans, horses have the predisposition to develop sepsis spontaneously and may be a promising model for spontaneous sepsis. This review proposes to give first an overview of the different animal species used to model human sepsis, and, secondly, to focus on adult equine sepsis as a spontaneous model of sepsis and its potential implications for human and veterinary medicine.

Plasma procalcitonin kinetics in healthy dogs and dogs undergoing tibial plateau leveling osteotomy

BACKGROUND

Procalcitonin (PCT) is a well-established biomarker for bacterial infection in human patients.

OBJECTIVES

We aimed to analyze the kinetics of plasma PCT (pPCT) in healthy dogs and dogs with canine cranial cruciate ligament (CCL) rupture undergoing tibial plateau leveling osteotomy (TPLO).

METHODS

This prospective, longitudinal study included 15 healthy dogs and 25 dogs undergoing TPLO. Hematology, pPCT, and C-reactive protein (CRP) were assessed on 3 consecutive days in healthy dogs and 1 day preoperatively and days 1, 2, 10, and 56 postoperatively. Inter- and intraindividual variability of pPCT were assessed in healthy dogs. Median pPCT concentrations of dogs with CCL rupture preoperatively were compared with healthy controls, and median pPCT concentrations, as well as percentage change post anesthesia, arthroscopy, and TPLO, were compared with baseline. For the correlation analysis, the Spearman rank correlation test was used.

RESULTS

Inter- and intraindividual variabilities of pPCT in healthy dogs were 36% and 15%, respectively. Median baseline pPCT concentrations were not significantly different between healthy dogs (118.9 pg/mL; IQR: 75.3-157.3 pg/mL) and dogs undergoing TPLO (95.9 pg/mL; IQR: 63.8-117.0 pg/mL). Plasma PCT concentrations were significantly lower immediately post- than preoperatively (P < 0.001). CRP, WBC, and neutrophil concentrations increased significantly on post-OP day 2 and had normalized by day 10.

CONCLUSIONS

These results indicate that CCL rupture, as well as anesthesia, arthroscopy, and TPLO combined, are not associated with increased pPCT concentrations in dogs with uncomplicated recovery. Considering the high intraindividual variability, individual serial measurements rather than a population-based reference interval should be considered.

The evolving value of older biomarkers in the clinical diagnosis of pediatric sepsis

Sepsis remains the leading cause of childhood mortality worldwide. The evolving definition of pediatric sepsis is extrapolated from adult studies. Although lacking formal validation in the pediatric population, this working definition has historically proven its clinical utility. Prompt identification of pediatric sepsis is challenging as clinical picture is often variable. Timely intervention is crucial for optimal outcome, thus biomarkers are utilized to aid in immediate, yet judicious, diagnosis of sepsis. Over time, their use in sepsis has expanded with discovery of newer biomarkers that include genomic bio-signatures. Despite recent scientific advances, there is no biomarker that can accurately diagnose sepsis. Furthermore, older biomarkers are readily available in most institutions while newer biomarkers are not. Hence, the latter's clinical value in pediatric sepsis remains theoretical. Albeit promising, scarce data on newer biomarkers have been extracted from research settings making their clinical value unclear. As interest in newer biomarkers continue to proliferate despite their ambiguous clinical use, the literature on older biomarkers in clinical settings continue to diminish. Thus, revisiting the evolving value of these earliest biomarkers in optimizing pediatric sepsis diagnosis is warranted. This review focuses on the four most readily available biomarkers to bedside clinicians in diagnosing pediatric sepsis. IMPACT: The definition of pediatric sepsis remains an extrapolation from adult studies. Older biomarkers that include C-reactive protein, procalcitonin, ferritin, and lactate are the most readily available biomarkers in most pediatric institutions to aid in the diagnosis of pediatric sepsis. Older biomarkers, although in varying levels of reliability, remain to be useful clinical adjuncts in the diagnosis of pediatric sepsis if used in the appropriate clinical context. C-reactive protein and procalcitonin are more sensitive and specific among these older biomarkers in diagnosing pediatric sepsis although evidence varies in different age groups and clinical scenarios.

Bifidobacterium lactis Probio-M8 improves bone metabolism in patients with postmenopausal osteoporosis, possibly by modulating the gut microbiota

PURPOSE

Postmenopausal osteoporosis (PMO) is usually managed by conventional drug treatment. However, prolonged use of these drugs cause side effects. Gut microbiota may be a potential target for treatment of PMO. This work was a three-month intervention trial aiming to evaluate the added effect of probiotics as adjunctive treatment for PMO.

METHODS

Forty patients with PMO were randomized into probiotic (n = 20; received Bifidobacterium animalis subsp. lactis Probio-M8 [Probio-M8], calcium, calcitriol) and placebo (n = 20; received placebo material, calcium, calcitriol) groups. The bone mineral density of patients was measured at month 0 (0 M; baseline) and month 3 (3 M; after three-month intervention). Blood and fecal samples were collected 0 M and 3 M. Only 15 and 12 patients from Probio-M8 and placebo groups, respectively, provided complete fecal samples for gut microbiota analysis.

RESULTS

No significant change was observed in the bone mineral density of patients at 3 M. Co-administering Probio-M8 improved the bone metabolism, reflected by an increased vitamin D3 level and decreased PTH and procalcitonin levels in serum at 3 M. Fecal metagenomic analysis revealed modest changes in the gut microbiome in both groups at 3 M. Interestingly, Probio-M8 co-administration affected the gut microbial interactive correlation network, particularly the short-chain fatty acid-producing bacteria. Probio-M8 co-administration significantly increased genes encoding some carbohydrate metabolism pathways (including ABC transporters, the phosphotransferase system, and fructose and mannose metabolism) and a choline-phosphate cytidylyltransferase.

CONCLUSIONS

Co-administering Probio-M8 with conventional drugs/supplements was more efficacious than conventional drugs/supplements alone in managing PMO. Our study shed insights into the beneficial mechanism of probiotic adjunctive treatment.

REGISTRATION NUMBER OF CLINICAL TRIAL

Chinese Clinical Trial Registry (identifier number: ChiCTR1800019268).

Combining Serum Procalcitonin Level, Thromboelastography, and Platelet Count to Predict Short-term Development of Septic Shock in Intensive Care Unit

OBJECTIVE

Despite the recent advances in diagnosis and treatment, sepsis continues to lead to high morbidity and mortality. Early diagnosis and prompt treatment are essential to save lives. However, most biomarkers can only help to diagnose sepsis, but cannot predict the development of septic shock in high-risk patients. The present study determined whether the combined measurement of procalcitonin (PCT), thromboelastography (TEG) and platelet (PLT) count can predict the development of septic shock.

METHODS

A retrospective study was conducted on 175 septic patients who were admitted to the intensive care unit between January 2017 and February 2021. These patients were divided into two groups: 73 patients who developed septic shock were assigned to the septic shock group, while the remaining 102 patients were assigned to the sepsis group. Then, the demographic, clinical and laboratory data were recorded, and the predictive values of PCT, TEG and PLT count for the development of septic shock were analyzed.

RESULTS

Compared to the sepsis group, the septic shock group had statistically lower PLT count and TEG measurements in the R value, K value, α angle, maximum amplitude, and coagulation index, but had longer prothrombin time (DT), longer activated partial thromboplastin time (APTT), and higher PCT levels. Furthermore, the Sequential Organ Failure Assessment (SOFA) score was higher in the septic shock group. The multivariate logistic regression analysis revealed that PCT, TEG and PLT count were associated with the development of septic shock. The area under the curve analysis revealed that the combined measurement of PCT, TEG and PLT count can be used to predict the development of septic shock with higher accuracy, when compared to individual measurements.

CONCLUSION

The combined measurement of PCT, TEG and PLT count is a novel approach to predict the development of septic shock in high-risk patients.

Effect of CytoSorb Coupled with Hemodialysis on Interleukin-6 and Hemodynamic Parameters in Patients with Systemic Inflammatory Response Syndrome: A Retrospective Cohort Study

Excessive release of cytokines during systemic inflammatory response syndrome (SIRS) often leads to refractory hypotension and multiple organ failure with high mortality. Cytokine removal with hemoadsorption has emerged as a possible adjuvant therapy, but data on interleukin-6 (IL-6) reduction and outcomes in clinical practice are scarce. We aimed to evaluate the effect of CytoSorb hemoadsorption on laboratory and clinical outcomes in shocked patients with SIRS. We designed a retrospective analysis of all patients with SIRS treated with CytoSorb in intensive care units (ICU). IL-6, laboratory and hemodynamic parameters were analyzed at approximate time intervals during CytoSorb treatment in the whole cohort and in a subgroup with septic shock. Observed and predicted mortality rates were compared. We included 118 patients with various etiologies of SIRS (septic shock 69%, post-resuscitation shock 16%, SIRS with acute pancreatitis 6%, other 9%); in all but one patient, CytoSorb was coupled with renal replacement therapy. A statistically significant decrease in IL-6 and vasopressor index with an increase in pH and mean arterial pressure was observed from 6 h onward. The reduction of lactate became significant at 48 h. Results were similar in a subgroup of patients with septic shock. Observed ICU and in-hospital mortalities were lower than predicted by Sequential Organ Failure Assessment (SOFA) (61% vs. 79%, p = 0.005) and Acute Physiology and Chronic Health Evaluation (APACHE) II (64% vs. 78%, p = 0.031) scores. To conclude, hemoadsorption in shocked patients with SIRS was associated with a rapid decrease in IL-6 and hemodynamic improvement, with improved observed vs. predicted survival. These results need to be confirmed in a randomized study.

Clinical usefulness of biomarkers for diagnosis and prediction of prognosis in sepsis and septic shock

Sepsis is a life-threatening condition and remains a major cause of mortality. The aim of this study was to evaluate the role of biomarkers in the diagnosis of sepsis and septic shock in patients admitted to the emergency department (ED). Medical records of patients who underwent measurement of serum biomarkers including lactic acid, C-reactive protein, procalcitonin (PCT), and presepsin in the ED between May 2019 and May 2020 were retrospectively reviewed. Patients were subdivided into 3 groups; non-sepsis, sepsis, and septic shock according to the new definition using the sequential organ failure assessment score. The mean age was 69.3 years, and 55.8% of the study population was female. Of 249 subjects, 98 patients confined to sepsis group, and 35.7% of them were septic shock. In the multivariable analysis, a high level of PCT was an independent predictor of sepsis (odds ratio [OR], 1.028; 95% confidence interval [CI], 1.006-1.051; P = .011) along with a simplified acute physiology score III (SAPS III) (OR, 1.082; 95% CI, 1.062-1.103, P < .001). PCT was also an independent risk factor for septic shock (OR, 1.043; 95% CI, 1.016-1.071, P = .02). In the receiver operating characteristic curve analysis, the area under the curve of PCT to predict sepsis and septic shock were 0.691 (P < .001) and 0.734 (P < .001), respectively. The overall 30-days mortality rate was 8.8%, and the mortality rate was significantly higher in the sepsis group (sepsis vs non-sepsis, 15.3% vs 4.6%; P = .004). In the multivariate Cox analysis, a higher level of lactic acid (hazard ratio [HR], 1.328; 95% CI, 1.061-1.663, P = .013), predisposing chronic pulmonary diseases (HR, 7.035; 95% CI, 1.687-29.341, P = .007), and a high SAPSIII value (HR, 1.046; 95% CI, 1.015-1.078, P = .003) were independent risk factors for mortality in sepsis patients. PCT was a useful biomarker for predicting sepsis and septic shock in the ED. A higher level of lactic acid, predisposing chronic pulmonary diseases, and a high SAPS III score were associated with a greater mortality risk in patients with sepsis.

Characterization of a proteomic profile associated with organ dysfunction and mortality of sepsis and septic shock

INTRODUCTION

The search for new biomarkers that allow an early diagnosis in sepsis and predict its evolution has become a necessity in medicine. The objective of this study is to identify, through omics techniques, potential protein biomarkers that are expressed in patients with sepsis and their relationship with organ dysfunction and mortality.

METHODS

Prospective, observational and single-center study that included adult patients (≥ 18 years) who were admitted to a tertiary hospital and who met the criteria for sepsis. A mass spectrometry-based approach was used to analyze the plasma proteins in the enrolled subjects. Subsequently, using recursive feature elimination classification and cross-validation with a vector classifier, an association of these proteins with mortality and organ dysfunction was established. The protein-protein interaction network was analyzed with String software.

RESULTS

141 patients were enrolled in this study. Mass spectrometry identified 177 proteins. Of all of them, and by recursive feature elimination, nine proteins (GPX3, APOB, ORM1, SERPINF1, LYZ, C8A, CD14, APOC3 and C1QC) were associated with organ dysfunction (SOFA > 6) with an accuracy of 0.82 ± 0.06, precision of 0.85 ± 0.093, sensitivity 0.81 ± 0.10, specificity 0.84 ± 0.10 and AUC 0.82 ± 0.06. Twenty-two proteins (CLU, LUM, APOL1, SAA1, CLEBC3B, C8A, ITIH4, KNG1, AGT, C7, SAA2, APOH, HRG, AFM, APOE, APOC1, C1S, SERPINC1, IGFALS, KLKB1, CFB and BTD) were associated with mortality with an accuracy of 0.86 ± 0.05, a precision of 0.91 ± 0.05, a sensitivity of 0.91 ± 0.05, a specificity of 0.72 ± 0.17, and an area under the curve (AUC) of 0.81 ± 0.08 with a confidence interval of 95%.

CONCLUSION

In sepsis there are proteomic patterns associated with organ dysfunction and mortality.

Bacterial Aspiration Pneumonia in Generalized Convulsive Status Epilepticus: Incidence, Associated Factors and Outcome

Suspicion of bacterial aspiration pneumonia (BAP) is frequent during generalized convulsive status epilepticus (GCSE). Early identification of BAP is required in order to avoid useless antibiotic therapy. In this retrospective monocentric study, we aimed to determine the incidence of aspiration syndrome and BAP in GCSE requiring mechanical ventilation (MV) and factors associated with the occurrence of BAP. Patients were older than 18 years and had GCSE requiring MV. To distinguish BAP from pneumonitis, tracheal aspirate and quantitative microbiological criterion were used. Out of 226 consecutive patients, 103 patients (46%) had an aspiration syndrome, including 54 (52%) with a BAP. Staphylococcus aureus represented 33% of bacterial strains. No relevant baseline characteristics differed, including serum levels of CRP, PCT, and albumin. The median duration of treatment for BAP was 7 days (5-7). Patients with BAP did not have a longer duration of MV (p = 0.18) and ICU stay (p = 0.18) than those with pneumonitis. At 3 months, 24 patients (44%) with BAP and 10 (27%) with pneumonitis had a poor functional outcome (p = 0.06). In conclusion, among patients with GCSE, half of the patients had an aspiration syndrome and one-quarter suffered from BAP. Clinical characteristics and biomarkers were not useful for differentiating BAP from pneumonitis. These results highlight the need for a method to rapidly differentiate BAP from pneumonitis, such as polymerase-chain-reaction-based techniques.

Guidelines for the Use of Procalcitonin for Rational Use of Antibiotics

How to cite this article: Khilnani GC, Tiwari P, Zirpe KG, Chaudhary D, Govil D, Dixit S, et al. Guidelines for the Use of Procalcitonin for Rational Use of Antibiotics. Indian J Crit Care Med 2022;26(S2):S77-S94.

Procalcitonin as a Candidate Biomarker for Malarial Infection and Severe Malaria: A Meta-Analysis

Procalcitonin (PCT), as a marker of malaria severity, remains to be investigated. The present study collated and compared the levels of PCT between patients with severe malaria, uncomplicated malaria, and control participants to assess their role in predicting malaria infection and disease severity. The systematic review was registered at PROSPERO with registration number CRD42021297243. The search for relevant studies that reported PCT in patients with malaria was performed in PubMed, Scopus, and Web of Science. The following meta-analyses were conducted; (1) the pooled mean PCT levels in patients with severe and uncomplicated malaria, and (2) the pooled mean difference in PCT levels between patients with severe and uncomplicated malaria. Fifteen studies were included for qualitative and quantitative syntheses. The meta-analysis results show that the pooled mean PCT levels in patients with uncomplicated malaria were 3.92 ng/mL (95% CI: 2.26-5.58 ng/mL, I²: 96.5, five studies), whereas the pooled mean PCT levels in patients with severe malaria were 14.13 ng/mL (95% CI: 8.75-19.5 ng/mL, I²: 92.6, six studies). The meta-analysis showed that patients with severe malaria had an equal mean of PCT compared to those with uncomplicated malaria when the random-effects model was used (p: 0.055, weighted mean difference: 6.93, 95% CI: -0.16-14.02, I²: 84.6%, four studies). There were probable correlations between the level of parasitemia, immunity level, and possibly bacterial or other parasitic co-infection that could affect the PCT level among different clinical severities of malaria. Therefore, the PCT level alone does not seem to be a suitable biomarker to discriminate the severe/uncomplicated or infected/uninfected cases. Further studies should investigate the increased PCT levels in combination with other markers in association with malaria infection and severity.

Pathophysiology of Sepsis and Genesis of Septic Shock: The Critical Role of Mesenchymal Stem Cells (MSCs)

The treatment of sepsis and septic shock remains a major public health issue due to the associated morbidity and mortality. Despite an improvement in the understanding of the physiological and pathological mechanisms underlying its genesis and a growing number of studies exploring an even higher range of targeted therapies, no significant clinical progress has emerged in the past decade. In this context, mesenchymal stem cells (MSCs) appear more and more as an attractive approach for cell therapy both in experimental and clinical models. Pre-clinical data suggest a cornerstone role of these cells and their secretome in the control of the host immune response. Host-derived factors released from infected cells (i.e., alarmins, HMGB1, ATP, DNA) as well as pathogen-associated molecular patterns (e.g., LPS, peptidoglycans) can activate MSCs located in the parenchyma and around vessels to upregulate the expression of cytokines/chemokines and growth factors that influence, respectively, immune cell recruitment and stem cell mobilization. However, the way in which MSCs exert their beneficial effects in terms of survival and control of inflammation in septic states remains unclear. This review presents the interactions identified between MSCs and mediators of immunity and tissue repair in sepsis. We also propose paradigms related to the plausible roles of MSCs in the process of sepsis and septic shock. Finally, we offer a presentation of experimental and clinical studies and open the way to innovative avenues of research involving MSCs from a prognostic, diagnostic, and therapeutic point of view in sepsis.

R, Patel PH, Bazan DZ, Mora A, Samuel N, Mingle AC, Leon LR, Varon J, Surani S. Drug-Induced Hyperthermia Review

Humans maintain core body temperature via a complicated system of physiologic mechanisms that counteract heat/cold fluctuations from metabolism, exertion, and the environment. Overextension of these mechanisms or disruption of body temperature homeostasis leads to bodily dysfunction, culminating in a syndrome analogous to exertional heat stroke (EHS). The inability of this thermoregulatory process to maintain the body temperature is caused by either thermal stress or certain drugs. EHS is a syndrome characterized by hyperthermia and the activation of systemic inflammation. Several drug-induced hyperthermic syndromes may resemble EHS and share common mechanisms. The purpose of this article is to review the current literature and compare exertional heat stroke (EHS) to three of the most widely studied drug-induced hyperthermic syndromes: malignant hyperthermia (MH), neuroleptic malignant syndrome (NMS), and serotonin syndrome (SS). Drugs and drug classes that have been implicated in these conditions include amphetamines, diuretics, cocaine, antipsychotics, metoclopramide, selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), and many more. Observations suggest that severe or fulminant cases of drug-induced hyperthermia may evolve into an inflammatory syndrome best described as heat stroke. Their underlying mechanisms, symptoms, and treatment approaches will be reviewed to assist in accurate diagnosis, which will impact the management of potentially life-threatening complications.

Biomarkers of sepsis in pigs, horses and cattle: from acute phase proteins to procalcitonin

Sepsis is a complex clinical syndrome triggered by an inflammatory host response to an infection. It is usually complicated to detect and diagnose, and has severe consequences in human and veterinary health, especially when treatment is not started early. Therefore, efforts to detect sepsis accurately are needed. In addition, its proper diagnosis could reduce the misuse of antibiotics, which is essential fighting against antimicrobial resistance. This case is a particular issue in farm animals, as antibiotics have been traditionally given massively, but now they are becoming increasingly restricted. When sepsis is suspected in animals, the most frequently used biomarkers are acute phase proteins such as C-reactive protein, serum amyloid A and haptoglobin, but their concentrations can increase in other inflammatory conditions. In human patients, the most promising biomarkers to detect sepsis are currently procalcitonin and presepsin, and there is a wide range of other biomarkers under study. However, there is little information on the application of these biomarkers in veterinary species. This review aims to describe the general concepts of sepsis and the current knowledge about the biomarkers of sepsis in pigs, horses, and cattle and to discuss possible advances in the field.

Regulation and Dysregulation of Endothelial Permeability during Systemic Inflammation

Systemic inflammation can be triggered by infection, surgery, trauma or burns. During systemic inflammation, an overshooting immune response induces tissue damage resulting in organ dysfunction and mortality. Endothelial cells make up the inner lining of all blood vessels and are critically involved in maintaining organ integrity by regulating tissue perfusion. Permeability of the endothelial monolayer is strictly controlled and highly organ-specific, forming continuous, fenestrated and discontinuous capillaries that orchestrate the extravasation of fluids, proteins and solutes to maintain organ homeostasis. In the physiological state, the endothelial barrier is maintained by the glycocalyx, extracellular matrix and intercellular junctions including adherens and tight junctions. As endothelial cells are constantly sensing and responding to the extracellular environment, their activation by inflammatory stimuli promotes a loss of endothelial barrier function, which has been identified as a hallmark of systemic inflammation, leading to tissue edema formation and hypotension and thus, is a key contributor to lethal outcomes. In this review, we provide a comprehensive summary of the major players, such as the angiopoietin-Tie2 signaling axis, adrenomedullin and vascular endothelial (VE-) cadherin, that substantially contribute to the regulation and dysregulation of endothelial permeability during systemic inflammation and elucidate treatment strategies targeting the preservation of vascular integrity.

Procalcitonin as a diagnostic marker for infection in sickle cell disease

Background: Patients with sickle cell disease (SCD) are at increased risk of infection. Fever often occurs with vaso-occlusive crisis (VOC), posing a diagnostic challenge in SCD. Procalcitonin (PCT) is an infectious biomarker validated in the general population but with limited data on use in SCD.Methods: We performed a retrospective single-center study (n=145) with primary objective of assessing ability of PCT to differentiate infection from VOC in SCD presenting with fever. Subgroups included confirmed bacterial infection (CBI), suspected bacterial infection, viral infection and VOC. A secondary objective examined association of PCT with acute chest syndrome. Clinical characteristics and data were collected and analyzed to assess diagnostic performance of PCT and associated variables.Results: The majority of patients were male with HbSS genotype, age ranging 18-73 years and mean of 34 years. Of the cohort, 16% had CBI and 8% had viral infection. PCT was able to discriminate CBI from viral infection [AUC=0.89 (95%CI, 0.78-0.99)] and VOC [AUC=0.87 (95%CI, 0.78-0.97)]. PCT had association with ACS but poor diagnostic performance [AUC=0.69 (95% CI, 0.54-0.84)].Conclusion: PCT has utility in distinguishing confirmed bacterial infection from VOC or viral infection and is a promising biomarker when investigating fever in SCD.

Clinical and biochemical endpoints and predictors of response to plasma exchange in septic shock: results from a randomized controlled trial

Background

Recently, a randomized controlled trial (RCT) demonstrated rapid but individually variable hemodynamic improvement with therapeutic plasma exchange (TPE) in patients with septic shock. Prediction of clinical efficacy in specific sepsis treatments is fundamental for individualized sepsis therapy.

Methods

In the original RCT, patients with septic shock of < 24 h duration and norepinephrine (NE) requirement ≥ 0.4 μg/kg/min received standard of care (SOC) or SOC + one single TPE. Here, we report all clinical and biological endpoints of this study. Multivariate mixed-effects modeling of NE reduction was performed to investigate characteristics that could be associated with clinical response to TPE.

Results

A continuous effect of TPE on the reduction in NE doses over the initial 24 h was observed (SOC group: estimated NE dose reduction of 0.005 µg/kg/min per hour; TPE group: 0.018 µg/kg/min per hour, p = 0.004). Similarly, under TPE, serum lactate levels, continuously decreased over the initial 24 h in the TPE group, whereas lactate levels increased under SOC (p = 0.001). A reduction in biomarkers and disease mediators (such as PCT (p = 0.037), vWF:Ag (p < 0.001), Angpt-2 (p = 0.009), sTie-2 (p = 0.005)) along with a repletion of exhausted protective factors (such as AT-III (p = 0.026), Protein C (p = 0.012), ADAMTS-13 (p = 0.008)) could be observed in the TPE but not in the SOC group. In a multivariate mixed effects model, increasing baseline lactate levels led to greater NE dose reduction effects with TPE as opposed to SOC (p = 0.004).

Conclusions

Adjunctive TPE is associated with the removal of injurious mediators and repletion of consumed protective factors altogether leading to preserved hemodynamic stabilization in refractory septic shock. We identified that baseline lactate concentration as a potential response predictor might guide future designing of large RCTs that will further evaluate TPE with regard to hard endpoints.

Trial registration Retrospectively registered 18th January 2020 at clinicaltrials.gov (Identifier: NCT04231994).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04003-2.

Comparison of a novel automated DiaSys procalcitonin immunoassay with four different BRAHMS-partnered immunoassays

Objectives

Procalcitonin (PCT) is an important biomarker of sepsis and respiratory infections. Various automated immunoassays for measuring PCT in patient plasma are available in medical laboratories. However, due to a lack of international reference material for PCT, the assays are not always comparable.

Design and methods

In this study, we compared a new turbidimetric immunoassay from DiaSys, measured on the Abbott Architect c16000 and Alinity c, with four BRAHMS-associated chemiluminescence immunoassays (Abbott Architect i2000SR, Alinity i, Roche Cobas e411 and DiaSorin Liaison XL) using 120 random patient plasma samples from the clinical laboratory routine at the University Medical Center Goettingen.

Results

The DiaSys assay showed clear differences as compared to the BRAHMS-associated assays when measured on Architect c: i.e. 58% positive mean bias vs. Architect i, 67% vs. Cobas and 23% vs. Liaison. As a result, additional 19% our patients would have a suspected bacterial infection, when using PCT values from the DiaSys assay and commonly accepted decision limits. A crosscheck of the DiaSys calibrator on the BRAHMS-associated systems showed a low recovery of the calibrator material (approx. 50%).

Conclusions

Overall, this study shows significant differences between the DiaSys and BRAHMS-associated assays. This could be attributed to a potential DiaSys calibrator problem. This highlights the need for an international reference material for harmonization of the PCT assays.

Measurement of procalcitonin in saliva of pigs: a pilot study

Background

Procalcitonin (PCT) is a widely used biomarker of sepsis in human medicine and can have potential applications in the veterinary field. This study aimed to explore whether PCT could be measured in the saliva of pigs and whether its concentration changes in sepsis. Therefore, a specific assay was developed and analytically validated, and changes in PCT concentration were evaluated in two conditions: a) in an experimental model of sepsis produced by the administration of lipopolysaccharide (LPS) to pigs (n = 5), that was compared with a model of non-septic inflammation induced by turpentine oil (n = 4), and b) in healthy piglets (n = 11) compared to piglets with meningitis (n = 20), a disease that usually involves sepsis and whose treatment often requires large amounts of antibiotics in farms.

Results

The assay showed coefficients of variation within the recommended limits and adequate linearity after serial sample dilutions. The method's detection limit was set at 68 μg/L, and the lower limit of quantification was 414 μg/L. In the LPS experiment, higher concentrations of PCT were found after 24 h in the animals injected with LPS (mean = 5790 μg/L) compared to those treated with turpentine oil (mean = 2127 μg/L, P = 0.045). Also, animals with meningitis had higher concentrations of PCT (mean = 21515 μg/L) than healthy pigs (mean = 6096 μg/L, P value < 0.0001).

Conclusions

According to these results, this assay could be potentially used as a tool for the non-invasive detection of sepsis in pigs, which is currently a topic of high importance due to antibiotic use restriction.

Procalcitonin is expressed in osteoblasts and limits bone resorption through inhibition of macrophage migration during intermittent PTH treatment

Intermittent injections of parathyroid hormone (iPTH) are applied clinically to stimulate bone formation by osteoblasts, although continuous elevation of parathyroid hormone (PTH) primarily results in increased bone resorption. Here, we identified Calca, encoding the sepsis biomarker procalcitonin (ProCT), as a novel target gene of PTH in murine osteoblasts that inhibits osteoclast formation. During iPTH treatment, mice lacking ProCT develop increased bone resorption with excessive osteoclast formation in both the long bones and axial skeleton. Mechanistically, ProCT inhibits the expression of key mediators involved in the recruitment of macrophages, representing osteoclast precursors. Accordingly, ProCT arrests macrophage migration and causes inhibition of early but not late osteoclastogenesis. In conclusion, our results reveal a potential role of osteoblast-derived ProCT in the bone microenvironment that is required to limit bone resorption during iPTH.

Procalcitonin Predicts Bacterial Infection, but Not Long-Term Occurrence of Adverse Events in Patients with Acute Coronary Syndrome

This study compiles data to determine if procalcitonin (PCT) values may predict both the risk of bacterial infection and potentially negative long-term outcomes in patients with acute coronary syndromes (ACS). All patients with a diagnosis of ACS that had PCT levels assessed during the first 24 h of hospitalization were enrolled in this study. The primary outcome was to detect the presence of bacterial infection defined as the occurrence of fever and at least one positive blood or urinary culture with clinical signs of infection. The secondary outcome was to monitor the occurrence after 1 year of the composite outcome of all-cause mortality, stroke and myocardial infarction. Overall, 569 patients were enrolled (mean age 69.37 ± 14 years, 30% females). Of these, 44 (8%) met the criteria for bacterial infection. After multivariate analysis, PCT and SBP were found to be independent predictors of bacterial infections (OR for PCT above the cut-off 2.67, 95% CI 1.09-6.53, p = 0.032 and OR for SBP 0.98, 95% CI 0.97-0.99, p = 0.043). After 1 year, the composite outcome of all-cause death, MI and stroke occurred in 104 patients (18%). PCT was not found to be an independent predictor of these outcomes. In conclusion, when assessing ACS, we found that testing for PCT levels during hospital admissions procedures was a good predictor of bacterial infections but not of all-cause mortality, stroke, or myocardial infarction. Clinicaltrial.org identifier: NCT02438085.

lncRNA GMDS‑AS1 upregulates IL‑6, TNF‑α and IL‑1β, and induces apoptosis in human monocytic THP‑1 cells via miR‑96‑5p/caspase 2 signaling

Long non-coding RNA (lncRNA) is considered a crucial modulator of the initiation and progression of several diseases. However, the roles of lncRNA in sepsis have yet to be fully elucidated. Thus, the aim of the present study was to investigate the effects of the lncRNA GDP-mannose 4,6-dehydratase antisense 1 (GMDS-AS1) and its target in order to understand its role in the pathogenesis of sepsis. An in vitro sepsis model was established by lipopolysaccharide (LPS) induction. Reverse transcription-quantitative PCR analysis was applied to detect the expression of inflammatory cytokines and the levels of GMDS-AS1, microRNA (miR)-96-5p and caspase-2 (CASP2). Flow cytometry was used to quantify the rate of apoptosis. In addition, the interaction between miR-96-5p and CASP2 was verified using a luciferase reporter assay. Western blot analysis was performed to assess the protein levels of CASP2 following alterations in GMDS-AS1 and miR-96-5p expression using transfection. The levels of interleukin (IL)-6, tumor necrosis factor-α and IL-1β were increased by LPS treatment in THP-1 cells, whereas miR-96-5p expression was downregulated. miR-96-5p overexpression inhibited LPS-induced inflammatory responses and apoptosis. In addition, GMDS-AS1 expression increased, and upregulation of GMDS-AS1 inhibited, the expression of miR-96-5p in the in vitro sepsis model. Moreover, CASP2 was confirmed to be a direct target of miR-96-5p. Therefore, the lncRNA GMDS-AS1 regulated inflammatory responses and apoptosis by modulating CASP2 and sponging miR-96-5p in LPS-induced THP-1 cells. In summary, the findings of the present study demonstrated that lncRNA GMDS-AS1 could promote the development of sepsis by targeting miR-96-5p/CASP2, indicating that the GMDS-AS1/miR-96-5p/CASP2 axis may be a new therapeutic target and potential research direction for sepsis therapy.

Calcitonin: current concepts and differential diagnosis

Calcitonin (CT) is most effectively produced by the parafollicular cells of the thyroid gland. It acts through the calcitonin receptor (CTR), a seven-transmembrane class II G-protein-coupled receptor linked to multiple signal transduction pathways with its main secretagogues being calcium and gastrin. It is clinically used mostly in the diagnosis and follow-up of medullary thyroid carcinoma (MTC). Hypercalcitoninemia can be attributed to primary (e.g. CT-secreting tumor) or secondary (e.g. due to hypercalcemia) overproduction, underexcretion (e.g. renal insufficiency), drug reaction (e.g. β-blockers), or false-positive results. In clinical practice, elevated basal calcitonin (bCT) is indicative, but not pathognomonic, of MTC. Current literature leans toward an age as well as gender-specific cutoff approach. bCT >100 pg/ml has up to 100% positive prognostic value (PPV) for MTC, whereas bCT between 8 and 100 pg/ml for adult males and 6 and 80 pg/ml for adult females should be possibly further investigated with stimulation calcitonin (sCT) tests. Calcium is showing similar efficacy with pentagastrin (Pg) sCT; however, the real value of these provocative tests has been disputed given the availability of new, highly sensitive CT immunoassays. Anyhow, evidence concludes that sCT <2 times bCT may not be suggestive of MTC, in which case, thyroid in addition to whole body workup based on clinical evaluation is further warranted. Moreover, measurement of basal and stimulated procalcitonin has been proposed as an emerging concept in this clinical scenario. Measuring bCT levels in patients with thyroid nodules as a screening tool for MTC remains another controversial topic. It has been well established, though, that bCT levels raise the sensitivity of FNAB (Fine Needle Aspiration Biopsy) and correlate with disease progression both pre- and postoperatively in this situation. There have been numerous reports about extrathyroidal neoplasms that express CT. Pancreatic, laryngeal, and lung neuroendocrine neoplasms (NENs) are most frequently associated with hypercalcitoninemia, but CT production has also been described in various other neoplasms such as duodenal, esophageal, cutaneous, and paranasal NENs as well as prostate, colon, breast, and lung non-NENs. This review outlines the current biosynthetic and physiology concepts about CT and presents up-to-date information regarding the differential diagnosis of its elevation in various clinical situations.

Incidence and risk factors of acute encephalopathy with biphasic seizures in febrile status epilepticus

OBJECTIVE

To clarify the incidence and risk factors of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) in pediatric patients with febrile status epilepticus (FSE).

METHODS

We retrospectively surveyed patients with FSE (≥20 min and ≥40 min) who were younger than 6 years by mailing a questionnaire to 1123 hospitals in Japan. The survey period was 2 years. We then collected clinical data on patients with prolonged febrile seizures (PFS) ≥40 min and those with AESD, and compared clinical data between the PFS and AESD groups.

RESULTS

The response rate for the primary survey was 42.3%, and 28.0% of hospitals which had applicable cases responded in the secondary survey. The incidence of AESD was 4.3% in patients with FSE ≥20 min and 7.1% in those with FSE ≥40 min. In the second survey, a total of 548 patients had FSE ≥40 min (AESD group, n = 93; PFS group, n = 455). Univariate analysis revealed significant between-group differences in pH, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine kinase, NH₃, procalcitonin (PCT), uric acid, blood urea nitrogen, creatinine (Cr), and lactate. Multivariate analysis using stratified values showed that high PCT was an only risk factor for AESD. A prediction score of ≥3 was indicative of AESD, as determined using the following indexes: HCO3^- < 20 mmol/L (1 point), Cl <100 mEq/L (1 point), Cr ≥0.35 mg/dL (1 point), glucose ≥200 mg/dL (1 point), and PCT ≥1.7 pg/mL (2 points). The scoring system had sensitivity of 84.2% and specificity of 81.0%.

CONCLUSION

Incidence data and prediction scores for AESD will be useful for future intervention trials for AESD.

Parecoxib ameliorates renal toxicity and injury in sepsis-induced mouse model and LPS-induced HK-2 cells

Parecoxib is a selective COX-2-specific inhibitor, which has been demonstrated to inhibit sepsis-induced systemic inflammation, but its role in sepsis-induced acute kidney injury has not been studied. This study was designed to investigate the effects of Parecoxib on sepsis-induced acute kidney injury. In this study, the mice sepsis model was established using an internationally recognized cecal ligation and puncture (CLP). Hematoxylin-eosin staining was performed to examine kidney injury. Biochemical kit was used to detect the expression of BUN and Cre in serum, and ELISA was used to detect the expression of inflammatory factors in renal tissue. Tunel staining was used to detect tissue apoptosis. Furthermore, CCK-8 assay was used to detect the cell viability of HK-2 cells and RT-qPCR was used to detect the expression of LPS-induced inflammatory factors in HK-2 cells.TUNEL staining was used to detect the level of cell apoptosis. Finally, the expressions of COX-2, p-NF-kB P65, p-IKKβ, NF-kB P65, IKKβ, Kim1, NGAL, iNOS, VEGF, VEGFR2, CD31 and apoptosis-related proteins in renal tissues and HK-2 cells were detected by Western blot. We discovered that parecoxib could alleviate renal pathological changes, reduce renal function injury, and inhibit renal pathology to inhibit the release of inflammatory factors in renal tissue. Parecoxib inhibited sepsis induced microvascular damage and apoptosis in renal tissue. Parecoxib reduced the inflammation and apoptosis of renal tubular epithelial cells induced by LPS. Our data suggest that Parecoxib ameliorates sepsis-induced kidney injury, and may have potential as a novel therapeutic method for treating sepsis-induced kidney injury.

Sputum procalcitonin: a potential biomarker in stable bronchiectasis

Sputum procalcitonin is elevated in exacerbations of bronchiectasis. The primary aim of this study was to investigate whether sputum procalcitonin levels are higher in patients with stable bronchiectasis than in healthy controls. We also assessed differences in procalcitonin levels in spontaneously expectorated and induced sputum samples and their repeatability 1 week later.

Participants included were aged over 18 years and either had radiologically confirmed bronchiectasis or were healthy controls. Patients with bronchiectasis were clinically stable for at least 6 weeks and had spontaneous and induced sputum collected at visit 1 and again 7 days later. Only induced sputum samples were collected from healthy controls during visit 1. Sputum procalcitonin concentrations in sputum were measured.

In total, 30 patients with bronchiectasis and 15 healthy controls were enrolled in this observational study. In the pooled data from visit 1 and 2, the geometric mean procalcitonin level in induced sputum was significantly higher in the bronchiectasis group than in the healthy control group (1.5 ng·mL⁻¹, 95% CI 1.0–2.1 ng·mL⁻¹versus 0.4 ng·mL⁻¹, 95% CI 0.2–0.9 ng·mL⁻¹; mean ratio 3.6, 95% CI 1.5–8.6; p=0.006). Mean procalcitonin level was higher in spontaneous sputum than in induced sputum at visit 1 (1.8 ng·mL⁻¹, 95% CI 1.2–2.7 ng·mL⁻¹versus 1.1 ng·mL⁻¹, 95% CI 0.7–1.8 ng·mL⁻¹) and visit 2 (1.5 ng·mL⁻¹, 95% CI 1.0–2.5 ng·mL⁻¹versus 1.2 ng·mL⁻¹, 95% CI 0.8–1.6 ng·mL⁻¹; p=0.001). Repeating spontaneous and induced sputum procalcitonin levels 1 week later produced similar concentrations (p=0.29, intraclass correlation coefficient (ICC)=0.76 and p=0.72, ICC=0.70, respectively).

Sputum procalcitonin is increased in patients with stable bronchiectasis and has potential as a biomarker of airway inflammation and infection in bronchiectasis.

Sputum procalcitonin levels are higher in patients with stable bronchiectasis than in healthy controls. Sputum procalcitonin has the potential to be a biomarker of airway inflammation and infection in bronchiectasis.https://bit.ly/3ivn7R9

The Urosepsis-A Literature Review

Urosepsis is a very serious condition with a high mortality rate. The immune response is in the center of pathophysiology. The therapeutic management of these patients includes surgical treatment of the source of infection, antibiotic therapy and life support. The management of this pathology is multidisciplinary and requires good collaboration between the urology, intensive care, imaging and laboratory medicine departments. An imbalance of pro and anti-inflammatory cytokines produced during sepsis plays an important role in pathogenesis. The study of cytokines in sepsis has important implications for understanding pathophysiology and for development of other therapeutic solutions. If not treated adequately, urosepsis may lead to serious septic complications and organ sequelae, even to a lethal outcome.

Global Lysine Acetylome Analysis of LPS-Stimulated HepG2 Cells Identified Hyperacetylation of PKM2 as a Metabolic Regulator in Sepsis

Sepsis-induced liver dysfunction (SILD) is a common event and is strongly associated with mortality. Establishing a causative link between protein post-translational modification and diseases is challenging. We studied the relationship among lysine acetylation (Kac), sirtuin (SIRTs), and the factors involved in SILD, which was induced in LPS-stimulated HepG2 cells. Protein hyperacetylation was observed according to SIRTs reduction after LPS treatment for 24 h. We identified 1449 Kac sites based on comparative acetylome analysis and quantified 1086 Kac sites on 410 proteins for acetylation. Interestingly, the upregulated Kac proteins are enriched in glycolysis/gluconeogenesis pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) category. Among the proteins in the glycolysis pathway, hyperacetylation, a key regulator of lactate level in sepsis, was observed at three pyruvate kinase M2 (PKM2) sites. Hyperacetylation of PKM2 induced an increase in its activity, consequently increasing the lactate concentration. In conclusion, this study is the first to conduct global profiling of Kac, suggesting that the Kac mechanism of PKM2 in glycolysis is associated with sepsis. Moreover, it helps to further understand the systematic information regarding hyperacetylation during the sepsis process.

Procalcitonin elevation induced by sympathomimetic drug overdose

Background

Procalcitonin, a biomarker used to detect systemic bacterial infection, can be elevated in other conditions. Some case reports have suggested procalcitonin elevation induced by drug overdose.

Case Presentation

A 20‐year‐old woman with insignificant medical history presented with vomiting, fever, and impaired consciousness. Her vital signs showed an altered mental status (Glasgow Coma Scale score, 11 [E4V1M6]) and high fever (38.0°C), and no significant neurological signs were detected. Laboratory tests revealed that her serum procalcitonin level was significantly high (>10 ng/dL). Gradually, her level of consciousness improved, and she admitted that she had taken an overdose of sympathomimetic drugs. She was discharged from the hospital on day 5 without any problems.

Conclusion

Drug overdose is seldom mentioned as one of the causes of serum procalcitonin level elevation. Sympathomimetic drug overdose can be one of the causes of procalcitonin elevation.

Predicting long-term cardiovascular outcomes in myocardial infarction survivors using multiple biomarkers

Aim: Although there are short- and long-term prognostic studies in patients with myocardial infarction (MI), the data that can be used to predict the clinical outcome following discharge is limited. Materials & methods: We analyzed creatinine kinase-MB and troponin related to myonecrosis, suppression of tumorigenicity 2 and NT-pro B-type natriuretic peptide related to myocardial stress, C-reactive protein and procalcitonin related to inflammation in 259 MI patients. Results: Being in the high group for myocardial stress (odds ratio [OR]: 3.45, 95% CI: 1.398-8.547, p = 0.004) and inflammation markers (OR: 4.30, 95% CI: 1.690-10.899, p = 0.001) predicted major cardiovascular adverse events while myonecrosis markers could not (OR: 1.70, 95% CI: 0.671-4.306, p = 0.263). Conclusion: Using multimarker risk stratification composed of inflammation and myocardial stress biomarkers improves the prediction of major cardiovascular adverse events in MI survivors.

Procalcitonin and Early Postoperative Infection After Pediatric Cardiopulmonary Bypass Surgery

OBJECTIVES

Systemic inflammation and bacterial infections are critical occurrences after pediatric cardiac surgery. Elevated white blood cell count and C-reactive protein cannot discriminate between these two conditions in the early postoperative period. The aim of this study was to understand whether procalcitonin (PCT) values within 48 hours of surgery could be a useful marker of postoperative infection.

DESIGN

Retrospective observational study.

SETTING

The study was performed in a teaching hospital.

PARTICIPANTS

All patients ≤six years of age.

INTERVENTIONS

Cardiac surgery on cardiopulmonary bypass from January 1, 2017 to January 1, 2020.

MEASUREMENT AND MAIN RESULTS

PCT, white blood cell count, and C-reactive protein values were measured at intensive care unit admission and at 24 and 48 hours after surgery. All positive cultures in the first seven days after surgery were recorded. Out of 177 consecutive patients, 22 (12%) developed infections. PCT at 48 hours after surgery was the only laboratory predictor of infections in the first seven days after surgery (p = 0.02). Receiver operating curve analyses on PCT values at 48 hours identified an optimal cut-off value of 1.85 ng/mL in the overall population. Area under the curve was 0.63, sensitivity 63%, and specificity 69%.

CONCLUSIONS

In light of this preliminary result, the clinical relevance and predictive accuracy of PCT are promising in patients with increasing values of PCT but need to be confirmed in a larger sample.

The Expanding Role of Biomarkers in Diagnosing Infection in Total Joint Arthroplasty: A Review of Current Literature

Consistent diagnosis of periprosthetic infection in total joint arthroplasty continues to elude the orthopedic surgeon because no gold standard test exists. Therefore clinicians must rely on a combination of tests to help aid the diagnosis. The expanding role of biomarkers has shown promising results to more accurately diagnose an infection when combined with clinical suspicion and bacterial culture testing. This paper reviews the diagnostic capabilities of the most current serum and synovial biomarkers as well as next generation sequencing in the setting of periprosthetic joint infection. Future research and high-powered studies will be necessary to determine sensitivity and specificity of each biomarker.

Heparin-binding protein and procalcitonin in the diagnosis of pathogens causing community-acquired pneumonia in adult patients: a retrospective study

The performance of inflammatory markers in community-acquired pneumonia (CAP) caused by different pathogens has not been fully studied. We sought to find the differences in the concentrations of procalcitonin (PCT) and heparin-binding protein (HBP) between patients with CAP caused by different pathogens. We enrolled 162 patients with CAP, divided into three groups on the basis of bacterial (n = 108), fungal (n = 21) and viral (n = 33) infection. Complete leukocyte counts and the concentration of HBP and PCT were measured, and the differences were compared with nonparametric tests. The receiver operating characteristic (ROC) curve was used to evaluate the significant differences in the sensitivity and specificity of the indicators. The leukocyte and neutrophils counts and the concentrations of HBP and PCT in the viral group were significantly lower than those in the other two groups (p < 0.001). The area under the ROC curve (AUC) of the concentration of HBP and PCT as well as leukocyte and neutrophils counts were 0.927, 0.892, 0.832 and 0.806 for distinguishing bacterial from viral infection, respectively. The best cut-off value was 20.05 ng/mL for HBP, with a sensitivity of 0.861 and specificity of 0.939. The best cut-off value was 0.195 ng/mL for PCT, with a sensitivity of 0.991 and specificity of 0.636. The best cut-off value was 5.195 × 10⁹/L and 4.000 × 10⁹/L for leukocyte and neutrophils counts, with sensitivity of 0.694 and 0.880 and specificity of 0.667 and 0.636, respectively. The AUC of HBP, PCT and leukocyte and neutrophil counts for distinguishing fungal from viral infection were 0.851, 0.883, 0.835 and 0.830, respectively. The best cut-off values were 29.950 ng/mL, 0.560 ng/mL, 5.265 × 10⁹/L and 3.850 × 10⁹/L, with sensitivity of 0.667, 0.714, 0.905 and 0.952 and specificity of 0.970, 0.879 0.667 and 0.606, respectively. There were no significant differences in the three indicators between the bacterial and fungal infection groups. The concentration of CRP showed no significant differences among the three groups. Consequently, the stronger immune response characterized by higher inflammation markers including HBP and PCT can help distinguish bacterial and fungal CAP from viral CAP.

Neglected Variables in the Interpretation of Serum Procalcitonin Levels in Patients With Septic Shock

The interpretation of serum procalcitonin (PCT) levels in septic patients is facilitated by reviewing the known stimuli that activate the PCT family of genes. Herein we describe 7 pathways that, alone or in combination, can increase serum PCT levels. As a marker of activation of innate immunity, high PCT levels affect clinical diagnosis, can be trended as a measure of "source" control, and can guide duration of antibacterial therapy in septic patients. Low PCT levels reflect little to no activation of an innate immune response, influence the differential diagnosis, and support the discontinuation of empiric antibiotic therapy. Understanding the pathways that result in elevated serum PCT levels is necessary for interpretation and subsequent clinical management.

Common and Novel Markers for Measuring Inflammation and Oxidative Stress Ex Vivo in Research and Clinical Practice-Which to Use Regarding Disease Outcomes?

Many chronic conditions such as cancer, chronic obstructive pulmonary disease, type-2 diabetes, obesity, peripheral/coronary artery disease and auto-immune diseases are associated with low-grade inflammation. Closely related to inflammation is oxidative stress (OS), which can be either causal or secondary to inflammation. While a low level of OS is physiological, chronically increased OS is deleterious. Therefore, valid biomarkers of these signalling pathways may enable detection and following progression of OS/inflammation as well as to evaluate treatment efficacy. Such biomarkers should be stable and obtainable through non-invasive methods and their determination should be affordable and easy. The most frequently used inflammatory markers include acute-phase proteins, essentially CRP, serum amyloid A, fibrinogen and procalcitonin, and cytokines, predominantly TNFα, interleukins 1β, 6, 8, 10 and 12 and their receptors and IFNγ. Some cytokines appear to be disease-specific. Conversely, OS-being ubiquitous-and its biomarkers appear less disease or tissue-specific. These include lipid peroxidation products, e.g., F2-isoprostanes and malondialdehyde, DNA breakdown products (e.g., 8-OH-dG), protein adducts (e.g., carbonylated proteins), or antioxidant status. More novel markers include also -omics related ones, as well as non-invasive, questionnaire-based measures, such as the dietary inflammatory-index (DII), but their link to biological responses may be variable. Nevertheless, many of these markers have been clearly related to a number of diseases. However, their use in clinical practice is often limited, due to lacking analytical or clinical validation, or technical challenges. In this review, we strive to highlight frequently employed and useful markers of inflammation-related OS, including novel promising markers.

LDH, CRP and ALB predict nucleic acid turn negative within 14 days in symptomatic patients with COVID-19

Aims

To search for biochemical indicators that can identify symptomatic patients with COVID-19 whose nucleic acid could turn negative within 14 days, and assess the prognostic value of these biochemical indicators in patients with COVID-19.

Patients and methods

We collected the clinical data of patients with COVID-19 admitted to our hospital, by using logistic regression analysis and AUC curves, explored the relationship between biochemical indicators and nucleic acid positive duration, the severity of COVID-19, and hospital stay respectively.

Results

A total of two hundred and thirty-three patients with COVID-19 were enrolled in the study. We found patients whose nucleic acid turned negative within 14 days had lower LDH, CRP and higher ALB (P < 0.05). ROC curve results indicated that lower LDH, TP, CRP and higher ALB predicted the nucleic acid of patients turned negative within 14 days with statistical significance(P < 0.05), AST, LDH, CRP and PCT predicted the severe COVID-19 with statistical significance, and CRP predicted hospital stay >31days with statistical significance (P < 0.05). After verification, the probability of nucleic acid turning negative within 14 days in patients with low LDH (<256 U/L), CRP (<44.5 mg/L) and high ALB (>35.8 g/L) was about 4 times higher than that in patients with high LDH, CRP and low ALB (P < 0.05).

Conclusions

LDH, CRP and ALB are useful prognostic marker for predicting nucleic acid turn negative within 14 days in symptomatic patients with COVID-19.