Update on procalcitonin measurements

Food-derived bioactive peptides potentiating therapeutic intervention in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that affects the joints of the human body and is projected to have a prevalence age-standardized rate of 1.5 million new cases worldwide by 2030. Several conventional and non-conventional preventive and therapeutic interventions have been suggested but they have their side effects including nausea, abdominal pain, liver damage, ulcers, heightened blood pressure, coagulation, and bleeding. Interestingly, several food-derived peptides (FDPs) from both plant and animal sources are increasingly gaining a reputation for their potential in the management or therapy of RA with little or no side effects. In this review, the concept of inflammation, its major types (acute and chronic), and RA identified as a chronic type were discussed based on its pathogenesis and pathophysiology. The conventional treatment options for RA were briefly outlined as the backdrop of introducing the FDPs that potentiate therapeutic effects in the management of RA.

The Role of Biomarkers in Diagnosis of Sepsis and Acute Kidney Injury

Sepsis and acute kidney injury (AKI) are two major public health concerns that contribute significantly to illness and death worldwide. Early diagnosis and prompt treatment are essential for achieving the best possible outcomes. To date, there are no specific clinical, imaging, or biochemical indicators available to diagnose sepsis, and diagnosis of AKI based on the KDIGO criterion has limitations. To improve the diagnostic process for sepsis and AKI, it is essential to continually evolve our understanding of these conditions. Delays in diagnosis and appropriate treatment can have serious consequences. Sepsis and AKI often occur together, and patients with kidney dysfunction are more prone to developing sepsis. Therefore, identifying potential biomarkers for both conditions is crucial. In this review, we talk about the main biomarkers that evolve the diagnostic of sepsis and AKI, namely neutrophil gelatinase-associated lipocalin (NGAL), proenkephalin (PENK), and cell-free DNA.

Progress in Procalcitonin Detection Based on Immunoassay

Procalcitonin (PCT) serves as a crucial biomarker utilized in diverse clinical contexts, including sepsis diagnosis and emergency departments. Its applications extend to identifying pathogens, assessing infection severity, guiding drug administration, and implementing theranostic strategies. However, current clinical deployed methods cannot meet the needs for accurate or real-time quantitative monitoring of PCT. This review aims to introduce these emerging PCT immunoassay technologies, focusing on analyzing their advantages in improving detection performances, such as easy operation and high precision. The fundamental principles and characteristics of state-of-the-art methods are first introduced, including chemiluminescence, immunofluorescence, latex-enhanced turbidity, enzyme-linked immunosorbent, colloidal gold immunochromatography, and radioimmunoassay. Then, improved methods using new materials and new technologies are briefly described, for instance, the combination with responsive nanomaterials, Raman spectroscopy, and digital microfluidics. Finally, the detection performance parameters of these methods and the clinical importance of PCT detection are also discussed.

Ultrasensitive and Rapid Detection of Procalcitonin via Waveguide-Enhanced Nanogold-Linked Immunosorbent Assay for Early Sepsis Diagnosis

Sepsis, a life-threatening inflammatory response, demands economical, accurate, and rapid detection of biomarkers during the critical "golden hour" to reduce the patient mortality rate. Here, we demonstrate a cost-effective waveguide-enhanced nanogold-linked immunosorbent assay (WENLISA) based on nanoplasmonic waveguide biosensors for the rapid and sensitive detection of procalcitonin (PCT), a sepsis-related inflammatory biomarker. To enhance the limit of detection (LOD), we employed sandwich assays using immobilized capture antibodies and detection antibodies conjugated to gold nanoparticles to bind the target analyte, leading to a significant evanescent wave redistribution and strong nanoplasmonic absorption near the waveguide surface. Experimentally, we detected PCT for a wide linear response range of 0.1 pg/mL to 1 ng/mL with a record-low LOD of 48.7 fg/mL (3.74 fM) in 8 min. Furthermore, WENLISA has successfully identified PCT levels in the blood plasma of patients with sepsis and healthy individuals, offering a promising technology for early sepsis diagnosis.

Establishment of a risk prediction model for bowel necrosis in patients with incarcerated inguinal hernia

INTRODUCTION

Incarceration occurred in approximately 5% to 15% of inguinal hernia patients, with around 15% of incarcerated cases progressing to intestinal necrosis, necessitating bowel resection surgery. Patients with intestinal necrosis had significantly higher mortality and complication rates compared to those without necrosis.The primary objective of this study was to design and validate a diagnostic model capable of predicting intestinal necrosis in patients with incarcerated groin hernias.

METHODS

We screened the clinical records of patients who underwent emergency surgery for incarcerated inguinal hernia between January 1, 2015, and December 31, 2022. To ensure balanced representation, the enrolled patients were randomly divided into a training set (n = 180) and a validation set (n = 76) using a 2:1 ratio. Logistic regression analysis was conducted using the rms package in R software, incorporating selected features from the LASSO regression model, to construct a predictive model.

RESULTS

Based on the results of the LASSO regression analysis, a multivariate logistic regression model was developed to establish the predictive model. The predictors included in the model were Abdominal effusion, Hernia Sac Effusion, and Procalcitonin. The area under the receiver operating characteristic (ROC) curve for the nomogram graph in the training set was 0.977 (95% CI = 0.957-0.992). In the validation set, the AUC for the nomogram graph was 0.970. Calibration curve and decision curve analysis (DCA) verified the accuracy and practicability of the nomogram graph in our study.

CONCLUSION

Bowel necrosis in patients with incarcerated inguinal hernia was influenced by multiple factors. The nomogram predictive model constructed in this study could be utilized to predict and differentiate whether incarcerated inguinal hernia patients were at risk of developing bowel necrosis.

Role of biomarkers in prognostication of moderate and severe COVID-19 cases

Background

COVID-19 pandemic demanded upgrading of laboratory medicine to limit morbidity, disability and mortality from moderate and severe SARS-COV-2 infections.

Objective

To assess among moderate and severe COVID-19 patients, C-reactive protein (CRP), procalcitonin (PCT), ferritin, D-dimer, interleukin 6 (IL-6), lactate dehydrogenase (LDH), total and differential leucocyte count (TLC and DLC), neutrophil-to-lymphocyte ratio (NLR), absolute platelet count (APC), prothrombin time (PT), activated partial thromboplastin time (APTT) and international normalized ratio (INR) to find their interdependence and role in prognosis.

Methods

This open label analytical cross-sectional noninterventional study evaluated array of independent biochemical, haematological and coagulopathy markers, viz. CRP, PCT, ferritin, D-dimer, IL-6, LDH, TLC, DLC, NLR, absolute platelet count, PT, APTT and INR on consecutive 100 patients with diagnosis of moderate and severe COVID-19 from July to August 2021.

Results

In our study, on consecutive designated 100 cases (55 cases moderate and 45 cases severe), more severity were reported as the age progressed; gender difference was not noted. Among independent markers, CRP, PCT, ferritin, D-dimer, IL-6 and LDH had statistically significant relation in comparison with severity of the disease as Chi-square calculated value (P < 0.05). TLC, DLC and APC showed no significant relation in comparison with severity of the disease; NLR had highly significant relation. PT showed significant relation in comparison with severity, though APTT and INR did not show significant relation.

Conclusion

Our research group felt that CRP, PCT, ferritin, D-dimer, IL-6, LDH and NLR should be in included in clinical practice guidelines to prognosticate COVID-19 cases. Furthermore, translational researches are needed at all levels of healthcare to improve validity for practices of primary care physicians.

Evaluation of 601 children with multisystem inflammatory syndrome (Turk MISC study)

PURPOSE

Due to its link with the 2019 coronavirus, the multisystem inflammatory syndrome in children (MISC) has garnered considerable international interest. The aim of this study, in which MISC patients were evaluated multicenter, and the data of the third period of the Turk-MISC study group, to compare the clinical and laboratory characteristics and outcomes of MISC patients who did and did not require admission to an intensive care unit (ICU).

METHODS

This retrospective multicenter observational study was carried out between June 11, 2021, and January 01, 2022. The demographics, complaints, laboratory results, system involvements, and outcomes of the patients were documented.

RESULTS

A total of 601 patients were enrolled; 157 patients (26.1%) required hospitalization in the intensive care unit (ICU). Median age was 8 years (interquartile range (IQR) 4.5-11.3 years. The proportion of Kawasaki disease-like features in the ICU group was significantly higher than in the non-ICU group (56.1% vs. 43.2% p = 0.006). The ICU group had considerably lower counts of both lymphocytes and platelets (lymphocyte count 900 vs. 1280 cells × μL, platelet count 153 vs. 212 cells × 103/ μL, all for p< 0.001). C-reactive protein, procalcitonin, and ferritin levels were significantly higher in the ICU group (CRP 164 vs. 129 mg/L, procalcitonin 9.2 vs. 2.2 μg/L, ferritin 644 vs. 334 μg/L, all for p< 0.001). Being between ages 5-12 and older than 12 increased the likelihood of hospitalization in the ICU by four [95% confidence intervals (CI)1.971-8.627] and six times (95% CI 2.575-14.654), respectively, compared to being between the ages 0-5. A one-unit increase in log D-dimer (µg/L) and log troponin (ng/L) was also demonstrated to increase the need for intensive care by 1.8 (95% CI 1.079-3.233) and 1.4 times (95% CI 1.133-1.789), respectively.     Conclusion: By comparing this study to our other studies, we found that the median age of MISC patients has been rising. Patients requiring an ICU stay had considerably higher levels of procalcitonin, CRP, and ferritin but significantly lower levels of lymphocyte and thrombocyte. In particular, high levels of procalcitonin in the serum might serve as a valuable laboratory marker for anticipating the need for intensive care.

WHAT IS KNOWN

• Lymphopenia and thrombocytopenia were an independent predictor factors in patients with MISC who needed to stay in intensive care unit. • The possibility of the need to stay in the intensive care unit in patients with MISC who had Kawasaki disease-like findings was controversial compared with those who did not.

WHAT IS NEW

• A one-unit increase log D dimer and log troponin was demonstrated to require for intensive care unit by 1.8 and 1.4 times, respectively. • Serum procalcitonin levels had the best performance to predict stay in the intensive care unit stay.

COVID-19, HIV, and Cryptococcal Meningitis Coinfections with Abnormal Laboratory Findings

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first introduced in China in 2019, and it has rapidly spread all around the world. Cryptococcus neoformans is the leading cause of fungal meningitis in human immunodeficiency virus- (HIV-) infected patients. A variety of laboratory tests have been introduced for rapid diagnosis of meningitis.

Methods

Here, we report a case of coinfection with COVID-19 and cryptococcal meningitis in a HIV-positive patient with abnormal laboratory findings. In this case, COVID-19 was positive by polymerase chain reaction (PCR) and computerized tomography (CT) scan diagnosis. Cryptococcal antigen testing of CSF was negative, whereas India ink staining and cerebrospinal fluid (CSF) culture confirmed the presence of C. neoformans.

Results

Although the patient was in a critical stage of illness, serum and CSF levels of procalcitonin were abnormally low, within normal limits. On the other hand, although initial lumbar puncture had showed elevated protein level, the repeat CSFs presented remarkably reduced protein levels. Our findings indicate that despite COVID-19 infection, procalcitonin level may remain normal in HIV-associated cryptococcal meningitis, and findings of an apparently normal procalcitonin level should not exclude the possibility of infection. Also, antigen testing may present false-negative result, and it should not be the sole laboratory method for diagnosis of infectious meningitis. Consequently, CSF culture and staining is recommended, even when antigen testing of organism is negative and CSF profile is unremarkable.

Conclusion

Laboratory information should be combined with a good understanding of clinical manifestations of patient to determine if meningitis is present and confirmed COVID-19 should not ignore possibility of other infections for consideration.

Surviving Sepsis After Burn Campaign

INTRODUCTION

The Surviving Sepsis Campaign was developed to improve outcomes for all patients with sepsis. Despite sepsis being the primary cause of death after thermal injury, burns have always been excluded from the Surviving Sepsis efforts. To improve sepsis outcomes in burn patients, an international group of burn experts developed the Surviving Sepsis After Burn Campaign (SSABC) as a testable guideline to improve burn sepsis outcomes.

METHODS

The International Society for Burn Injuries (ISBI) reached out to regional or national burn organizations to recommend members to participate in the program. Two members of the ISBI developed specific "patient/population, intervention, comparison and outcome" (PICO) questions that paralleled the 2021 Surviving Sepsis Campaign [1]. SSABC participants were asked to search the current literature and rate its quality for each topic. At the Congress of the ISBI, in Guadalajara, Mexico, August 28, 2022, a majority of the participants met to create "statements" based on the literature. The "summary statements" were then sent to all members for comment with the hope of developing an 80% consensus. After four reviews, a consensus statement for each topic was created or "no consensus" was reported.

RESULTS

The committee developed sixty statements within fourteen topics that provide guidance for the early treatment of sepsis in burn patients. These statements should be used to improve the care of sepsis in burn patients. The statements should not be considered as "static" comments but should rather be used as guidelines for future testing of the best treatments for sepsis in burn patients. They should be updated on a regular basis.

CONCLUSION

Members of the burn community from the around the world have developed the Surviving Sepsis After Burn Campaign guidelines with the goal of improving the outcome of sepsis in burn patients.

Biomarkers and optical based biosensors in cardiac disease detection: early and accurate diagnosis

Rapid and precise detection methods for the early-stage detection of cardiovascular irregularities are crucial to stopping and reducing their development. Cardiovascular diseases (CVDs) are the leading cause of death in the world. Hence, cardiac-related biomarkers are essential for monitoring and managing of process. The necessity for biomarker detection has significantly widened the field of biosensor development. Bio-sensing methods offer rapid detection, low cost, sensitivity, portability, and selectivity in the development of devices for biomarker detection. For the prediction of cardiovascular diseases, some biomarkers can be used, like C-reactive protein (CRP), troponin I or T, creatine kinase (CK-MB), B-type natriuretic peptide (BNP), myoglobin (Mb), suppression of tumorigenicity 2 protein (ST2) and galectin-3 (Gal3). In this review, recent research studies were covered for gaining insight into utilizing optical-based biosensors, including surface plasmon resonance (SPR), photonic crystals (PCs), fluorescence-based techniques, fiber optics, and also Raman spectroscopy biosensors for the ultrasensitive detection of cardiac biomarkers. The main goal of this review is to focus on the improvement of optical biosensors in the future for the diagnosis of heart diseases and to discuss how to enhance their properties for use in medicine. Some main data from each study reviewed are emphasized, including the CVD biomarkers and the response range of the optical-based devices and biosensors.

Reduced Reliability of Procalcitonin (PCT) as a Biomarker of Bacterial Superinfection: Concerns about PCT-Driven Antibiotic Stewardship in Critically Ill COVID-19 Patients-Results from a Retrospective Observational Study in Intensive Care Units

BACKGROUND

The aim of this study was to assess whether procalcitonin levels is a diagnostic tool capable of accurately identifying sepsis and ventilator-associated pneumonia (VAP) even in critically ill COVID-19 patients.

METHODS

In this retrospective, observational study, all critically ill COVID-19 patients who survived for ≥2 days in a single university hospital and had at least one serum procalcitonin (PCT) value and associated blood culture and/or culture from a lower respiratory tract specimen available were eligible for the study.

RESULTS

Over the research period, 184 patients were recruited; 67 VAP/BSI occurred, with an incidence rate of 21.82 episodes of VAP/BSI (95% CI: 17.18-27.73) per 1000 patient-days among patients who were included. At the time of a positive microbiological culture, an average PCT level of 1.25-3.2 ng/mL was found. Moreover, also in subjects without positive cultures, PCT was altered in 21.7% of determinations, with an average value of 1.04-5.5 ng/mL. Both PCT and PCT-72 h were not linked to a diagnosis of VAP/BSI in COVID-19 patients, according to the multivariable GEE models (aOR 1.13, 95% CI 0.51-2.52 for PCT; aOR 1.32, 95% CI 0.66-2.64 for PCT-72 h).

CONCLUSION

Elevated PCT levels might not always indicate bacterial superinfections or coinfections in a severe COVID-19 setting.

Management of Intra-Abdominal Infections: The Role of Procalcitonin

Patients with intra-abdominal sepsis suffer from significant mortality and morbidity. The main pillars of treatment for intra-abdominal infections are (1) source control and (2) early delivery of antibiotics. Antibiotic therapy should be started as soon as possible. However, the duration of antibiotics remains a matter of debate. Prolonged antibiotic delivery can lead to increased microbial resistance and the development of nosocomial infections. There has been much research on biomarkers and their ability to aid the decision on when to stop antibiotics. Some of these biomarkers include interleukins, C-reactive protein (CRP) and procalcitonin (PCT). PCT's value as a biomarker has been a focus area of research in recent years. Most studies use either a cut-off value of 0.50 ng/mL or an >80% reduction in PCT levels to determine when to stop antibiotics. This paper performs a literature review and provides a synthesized up-to-date global overview on the value of PCT in managing intra-abdominal infections.

Optical method supported by machine learning for urinary tract infection detection and urosepsis risk assessment

The study presents an optical method supported by machine learning for discriminating urinary tract infections from an infection capable of causing urosepsis. The method comprises spectra of spectroscopy measurement of artificial urine samples with bacteria from solid cultures of clinical E. coli strains. To provide a reliable classification of results assistance of 27 algorithms was tested. We proved that is possible to obtain up to 97% accuracy of the measurement method with the use of use of machine learning. The method was validated on urine samples from 241 patients. The advantages of the proposed solution are the simplicity of the sensor, mobility, versatility, and low cost of the test.

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.

Serum Procalcitonin (PCT) - Is there a Role as an Early Biomarker in Infected Diabetic Foot Ulcer (IDFU) Patients?

Introduction

Infected diabetic foot ulcers may lead to serious complications if not recognised in the early stage. Diagnosis of infection is particularly challenging at that stage; thus, a sensitive inflammatory biomarker may be helpful. We aimed to evaluate the role of procalcitonin (PCT) as an early biomarker for infected diabetic foot ulcers (IDFU).

Materials and method

This cross-sectional study was conducted at Klinik Rawatan Keluarga (KRK), Orthopedic clinic and wards in Hospital Universiti Sains Malaysia (USM) from May 2020 to December 2020. A total of 264 participants were recruited and divided into three groups: 50 diabetic patients with no ulcers (control), 107 patients with non-infected diabetic foot ulcers (NIDFU), and 107 patients with infected diabetic foot ulcers (IDFU). The level of PCT was taken for all patients. Total white count (TWC) and C-reactive protein (CRP) were taken only for IDFU patients. Diagnosis of infection was based on the Infectious Disease Society of America-International Working Group of Diabetic Foot (IDSA-IMWGDF), and the severity of infection was graded according to the Wagner Classification.

Results

The level of PCT was higher in IDFU than in NIDFU and diabetic patient, with a median (IQR) of 0.355 (0.63) ng/mL, 0.077 (0.15) ng/mL and 0.028 (0.02) ng/mL, respectively. PCT and CRP showed moderate positive correlations in IDFU patients (p<0.001). The sensitivity and specificity were 63.6% and 83.2%, respectively, at the best cut-off at 0.25 ng/mL.

Conclusion

PCT is a valuable biomarker for the diagnosis of infection; however, it adds little value in the early diagnosis of IDFU in view of its low sensitivity.

Childhood Pneumonia: What's Unchanged, and What's New?

Childhood pneumonia is still a significant clinical and public health problem. India contributes the highest number of deaths due to pneumonia, accounts for about 20% of global mortality among under five children. Various etiologic agents including bacteria, viruses and atypical organism are responsible for childhood pneumonia. Recent studies suggest that viruses are one of the major causes of childhood pneumonia. Among viruses, respiratory syncytial virus has got great attention and several recent studies are reporting it as an important organism for pneumonia. Lack of exclusive breast feeding during first six months, improper timing of start and content of complimentary feeding, anemia, undernutrition, indoor pollution due to tobacco smoking and use of coal and wood for cooking food and lack of vaccinations are important risk factors. X-ray chest is not routinely performed to diagnose pneumonia while use of lung ultrasound is increasing to detect consolidation, pleural effusion, pneumothorax and pulmonary edema (interstitial syndrome). Role of C-reactive protein (CRP) and procalcitonin is similar, to differentiate between viral and bacterial pneumonia, however duration of antibiotics is better guided by procalcitonin. Newer biomarkers like IL-6, presepsin and triggering receptor expressed on myeloid cells 1 are needed to be evaluated for their use in children. Hypoxia is significantly associated with childhood pneumonia. Therefore, use of pulse oximetry should be encouraged for early detection and prompt treatment of hypoxia to prevent adverse outcomes. Among the available tools for risk of mortality assessment in children due to pneumonia, PREPARE score is the best but external validation will be needed.

Inflammatory blood parameters as prognostic factors for implant-associated infection after primary total hip or knee arthroplasty: a systematic review

BACKGROUND

Implant-associated infection (IAI) is a potential complication following total hip (THA) or knee arthroplasty (TKA). The initial phase of the inflammatory process can be measured by applying one of the inflammatory blood parameters (IBP). This systematic review aims to assess the response of IBP to trauma caused by orthopedic surgery and evaluate the clinical utility of quantitative measurements of IBP as prognostic factors for infection.

METHODS

All studies indexed in Ovid MEDLINE (PubMed), Ovid EMBASE, the Cochrane Library and the ISI Web of Science databases, from inception until January 31, 2020, were analyzed. Studies included were those on adults who underwent THA or TKA with minimum follow up of 30 days after surgery. In addition to minimum follow up, data on the prognostic factors for pre- or post-THA/TKA IAI were mandatory. The Quality Assessment of Diagnostic Accuracy tool (version 2) (QUADAS-2) and Standards for Reporting of Diagnostic Accuracy Studies guideline 2015 (STARD) were used for quality assessment.

RESULTS

Twelve studies fulfilled the inclusion and exclusion criteria. C-reactive protein was analyzed in seven studies, interleukin-6 in two studies and erythrocyte sedimentation rate in eight studies. White blood cell count and procalcitonin were analyzed in the only study. The overall quality of included studies was low. A potential for other cytokines (IL-1ra, IL-8) or MCP-1 was observed.

CONCLUSIONS

This is the first systematic review of IBP response to orthopedic surgery which identified some IBP for pre/post-operative screening, despite insufficient data supporting their prognostic potential for patient risk stratification.

Biophysical Changes of Leukocyte Activation (and NETosis) in the Cellular Host Response to Sepsis

Sepsis, the leading cause of mortality in hospitals, currently lacks effective early diagnostics. A new cellular host response test, the IntelliSep test, may provide an indicator of the immune dysregulation characterizing sepsis. The objective of this study was to examine the correlation between the measurements performed using this test and biological markers and processes associated with sepsis. Phorbol myristate acetate (PMA), an agonist of neutrophils known to induce neutrophil extracellular trap (NET) formation, was added to whole blood of healthy volunteers at concentrations of 0, 200, and 400 nM and then evaluated using the IntelliSep test. Separately, plasma from a cohort of subjects was segregated into Control and Diseased populations and tested for levels of NET components (citrullinated histone (cit-H3) DNA and neutrophil elastase (NE) DNA) using customized ELISA assays and correlated with ISI scores from the same patient samples. Significant increases in IntelliSep Index (ISI) scores were observed with increasing concentrations of PMA in healthy blood (0 and 200: p < 10-10; 0 and 400: p < 10-10). Linear correlation was observed between the ISI and quantities of NE DNA and Cit-H3 DNA in patient samples. Together these experiments demonstrate that the IntelliSep test is associated with the biological processes of leukocyte activation and NETosis and may indicate changes consistent with sepsis.

Age, comorbidities, c-reactive protein and procalcitonin as predictors of severity in confirmed COVID-19 patients in the Philippines

Background

The Coronavirus Disease 2019 (COVID-19) pandemic has been affecting people globally, and the Philippines is one of the countries greatly struck by the virus. The continued rise of new positive cases has drawn attention to the urgent need for healthcare management to cope with this challenge. Severity prediction could help improve medical decision-making and optimise the patient's treatment plan with a good clinical outcome. This study aimed to identify the determinants of COVID-19 disease severity.

Methods

Demographic characteristics and laboratory findings were collected from electronic medical records and paper forms of all confirmed COVID-19 cases reported by the University of Perpetual Help DALTA Medical Center between the September 1, 2020 and the October 31, 2021. We performed statistical analyses and interpretation of data to compare severe and non-severe groups.

Results

5,396 confirmed cases were examined. Most of the severe cases were elderly, male, had blood type A, and with comorbidities. Cycle threshold (Ct) values were lower in the severe group. Most patients had higher-than-normal levels of all blood parameters except platelet, white blood cell (WBC), neutrophil, and lymphocyte counts. Age, sex, ABO blood groups, comorbidities, open reading frame 1 ab (ORF1ab) and nucleocapsid (N) gene Ct values, ferritin, C-reactive protein (CRP), procalcitonin (PCT), D-dimer, white blood cell (WBC) count, neutrophil count, and lymphocyte count were significantly associated with disease severity. In multivariate analysis, age groups >60 and 30–59 years, presence of comorbidities, CRP level >5 ng/mL, and PCT >0.05 ng/mL were identified as disease severity predictors.

Conclusions

Based on our results, age, comorbidities, CRP, and PCT level may be utilised as primary assessment factors for possible hospital admission and close monitoring upon testing. Early detection of these risk factors may provide strategic interventions that help reduce mortality, hospital admissions, and more expensive and extensive treatments.

Simultaneous determination of procalcitonin and interleukin-6 in human serum samples with a point-of-care biosensing device

The simultaneous determination of two inflammatory diseases biomarkers, namely procalcitonin (PCT) and interleukin-6 (IL-6), in human serum samples employing a Point-of-Care device based on Multi Area Reflectance Spectroscopy is presented. Dual-analyte detection was achieved using silicon chips with two silicon dioxide areas of different thickness, one functionalized with an antibody specific for PCT and the other with an antibody specific for IL-6. The assay included reaction of immobilized capture antibodies with mixtures of PCT and IL-6 calibrators with the biotinylated detection antibodies, streptavidin and biotinylated-BSA. The reader provided for the automated execution of the assay procedure, as well as for the collection and processing of the reflected light spectrum, the shift of which is correlated to analytes concentration in the sample. The assay was completed in 35 min and the detection limits for PCT and IL-6 were 2.0 and 0.01 ng/mL respectively. The dual-analyte assay was characterized by high reproducibility (the intra- and inter-assay coefficients of variation were less than 10% for both analytes) and accuracy (the percent recovery values ranged from 80 to 113% for both analytes). Moreover, the values determined for the two analytes in human serum samples with the assay developed were in good agreement with the values determined for the same samples by clinical laboratory methods. These results support the potential of the proposed biosensing device application for inflammatory biomarkers determination at the Point-of-Need.

Comparing the predictive values of procalcitonin/albumin ratio and other inflammatory markers in determining COVID-19 severity

Objective

To examine the relationship between COVID-19 severity and procalcitonin/albumin ratio (PAR) and compare the PAR with oft-reported inflammatory markers, including procalcitonin, white blood cell (WBC), neutrophil/lymphocyte ratio (NLR) and C-reactive protein (CRP).

Methods

In this retrospective research study conducted at Sanliurfa Training and Research Hospital during May to September 2020; total, 577 adult subjects diagnosed with COVID-19 were included and categorized into two groups based on place of hospitalization: the intensive care unit (ICU) group (n=151) and the general ward (GW) group (n=426). Laboratory test results and demographic characteristics of the subjects were recorded.

Results

PAR, NLR, CRP, WBC, neutrophil and procalcitonin values were markedly higher in the ICU group than in the GW group. On the contrary, lymphocyte count and albumin level were markedly lower. PAR showed positive correlations with WBC, NLR, and CRP. Multivariate analysis showed that advanced age, presence of hypertension, elevated PAR, WBC, NLR, urea and lactate dehydrogenase levels were independent risk factors associated with the need for intensive care in COVID-19 subjects. Among them, the PAR showed the highest odds ratio (5.564) for ICU admission. Additionally, the area under the ROC curve of the PAR (0.888) was markedly greater than that of WBC (0.777), NLR (0.822), CRP (0.842) and procalcitonin (0.870).

Conclusions

This study revealed that PAR was superior to procalcitonin, WBC, NLR and CRP in determining COVID-19 severity. PAR was an important predictor of ICU requirement in COVID-19 cases.

Does Venipuncture Increase Lymphedema by Triggering Inflammation or Infection? An Experimental Rabbit Ear Lymphedema Model Study

Background: Recent guidelines recommend avoiding venipuncture to prevent lymphedema for breast cancer patients. This study investigated whether single or multiple sterile venipuncture procedures develop a systemic inflammation or infection and increase lymphedema in the rabbit ear lymphedema model. Methods and Results: Eighteen New Zealand white female rabbits were included. The right ear lymphedema model was created by surgical procedure; then, rabbits were divided into three randomized groups. Single and multiple venipuncture procedures were applied at least the 60th day after surgery for Group I and II, respectively. Group III was a control group. C-reactive protein (CRP) and procalcitonin (PCT) levels were analyzed to determine inflammation and infection. Ear thickness measurements were applied using a vernier caliper to assess the differences in lymphedema between the ears. All rabbits were euthanized on the 90th day after surgery. Histopathological analysis was performed to evaluate lymphedema by measuring tissue thicknesses. Ear thickness measurements showed that ear lymphedema was developed and maintained with surgical operation in all groups (p < 0.05). There was no difference in the ear thickness measurements between and within-groups results (p > 0.05). CRP and PCT levels were below the lower detection levels in all groups. According to the differences of histopathological ear distances, there were significant differences within-groups for all groups (p < 0.05), and no differences were identified between groups (p > 0.05). Conclusion: This experimental study demonstrated that single or multiple sterile venipuncture procedures did not trigger infection or inflammation and did not exacerbate ear lymphedema in the rabbit ear lymphedema model.

Diagnostic and therapeutic value of biomarkers in urosepsis

Urosepsis is sepsis caused by urogenital tract infection and is one of the most common critical illnesses in urology. If urosepsis is not diagnosed early, it can rapidly progress and worsen, leading to increased mortality. In recent years, with the increase of urinary tract surgery, the incidence of urosepsis continues to rise, posing a serious threat to patients. Early diagnosis of urosepsis, timely and effective treatment can greatly reduce the mortality of patients. Biomarkers such as WBC, NLR, PCT, IL-6, CRP, lactate, and LncRNA all play specific roles in the early diagnosis or prognosis of urosepsis. In addition to the abnormal increase of WBC, we should be more alert to the rapid decline of WBC. NLR values were superior to WBC counts alone in predicting infection severity. Compared with several other biomarkers, PCT values can differentiate between bacterial and non-bacterial sepsis. IL-6 always has high sensitivity and specificity for the diagnosis of sepsis, and CRP also has high sensitivity and specificity for the diagnosis of urosepsis. Lactic acid is closely related to the prognosis of patients with urosepsis. LncRNAs may be potential biomarkers of urosepsis. This article summarizes the main biomarkers, hoping to provide a reference for the timely diagnosis and evaluation of urosepsis.

Optically Active Nanomaterials and Its Biosensing Applications-A Review

This article discusses optically active nanomaterials and their optical biosensing applications. In addition to enhancing their sensitivity, these nanomaterials also increase their biocompatibility. For this reason, nanomaterials, particularly those based on their chemical compositions, such as carbon-based nanomaterials, inorganic-based nanomaterials, organic-based nanomaterials, and composite-based nanomaterials for biosensing applications are investigated thoroughly. These nanomaterials are used extensively in the field of fiber optic biosensing to improve response time, detection limit, and nature of specificity. Consequently, this article describes contemporary and application-based research that will be of great use to researchers in the nanomaterial-based optical sensing field. The difficulties encountered during the synthesis, characterization, and application of nanomaterials are also enumerated, and their future prospects are outlined for the reader's benefit.

Appearance of food-dependent exercise-induced anaphylaxis as an inflammatory disease: a pediatric case report and differential diagnosis

Anaphylaxis is the most serious of all allergic reactions. Despite advances in the knowledge of anaphylaxis, its clinical manifestations continue to be under-recognized. Indeed, proper diagnosis of anaphylaxis is often missed, and the treatment is delayed. The underlying causes are still under investigation globally. Inflammation represents the cornerstone of pathophysiology of anaphylaxis. Food-dependent exercise-induced anaphylaxis (FDEIA) is a rare clinical manifestation characterized by a chronological sequence in which food ingestion followed by physical exercise leads to anaphylaxis. Its mechanisms are yet to be fully explained. We report the case of a 14-year-old Chinese male who lost consciousness while undergoing physical activity at school. Several differential diagnoses were considered such as hypovolemic shock, septic shock, anaphylactic shock or neurological adverse event. Finally, the diagnosis of FDEIA was made. This case highlights the difficulties in diagnosing FDEIA and its management, especially when the clinical history is not complete and detailed.

IBM WATSON Trauma Pathway Explorer© as a Predictor for Sepsis after Polytrauma - Is Procalcitonin Useful for Identifying Septic Polytrauma Patients?

IBM and the University Hospital Zurich have developed an online tool for predicting outcomes of a patient with polytrauma, the IBM WATSON Trauma Pathway Explorer^® . The three predicted outcomes are Systemic Inflammatory Response Syndrome (SIRS) and sepsis within 21 days as well as early death within 72 hours since the admission of the patient. The validated Trauma Pathway Explorer^® offers insights into the most common laboratory parameters, such as procalcitonin (PCT). Sepsis is one of the most important complications after polytrauma, which is why it is crucial to detect it early. This study aimed to examine the time-dependent relationship between PCT values and sepsis, based on the WATSON technology. A total of 3653 patients were included, and ongoing admissions are incorporated continuously. Patients were split into two groups (sepsis and non-sepsis), and the PCT value was assessed for 21 days (1, 2, 3, 4, 6, 8, 12, 24, 48 hours, and 3, 4, 5, 7, 10, 14 and 21 days). The Mann-Whitney U-Test was used to evaluate the difference between the two groups. Binary logistic regression was utilized to examine the dependency of prediction. The Closest Top-left Threshold Method provided time-specific thresholds at which the PCT level is predictive for sepsis. At p <0.05, the data were declared significant. R was used to conduct all statistical analyses. The Mann-Whitney U-test showed a significant difference in PCT values in sepsis and non-sepsis patients between 12 and 24 hours, including post-hoc analysis (p <0.05). Likewise, the p-value started to be significant between 12 and 24 hours in the binary logistic regression (p <0.05). The threshold value of PCT to predict sepsis at 24 hours is 0.7μg/l, and at 48 hours 0.5μg/l. The presented time course of PCT levels in polytrauma patients shows the PCT as a separate predictor for sepsis relatively early. Even later, during the 21-day observation period, time-dependent PCT values may be utilized as a benchmark for the early and preemptive detection of sepsis, which may reduce death from septic shock and other deadly infectious episodes.

C‐reactive protein, procalcitonin, and erythrocyte sedimentation rate for the diagnosis of lower urinary tract infection in older people

This is a protocol for a Cochrane Review (diagnostic). The objectives are as follows:

Clinical Utility of Procalcitonin on Antibiotic Stewardship: A Narrative Review

Procalcitonin (PCT) was discovered as a useful marker for bacterial infection. Following its discovery, there have been a substantial number of clinical studies conducted to evaluate the presence of bacterial infections, and to guide antibiotic treatment by the stratified levels of PCT. Clinical evidence suggests that antibiotic treatment by PCT-guided antibiotic stewardship has been associated with a reduction in antibiotic usage without an increase in adverse outcomes. The use of PCT was approved by the Food and Drug Administration in the United States of America in 2017 to guide antibiotic treatment in sepsis and lower respiratory tract infections (LRTIs). In Korea, the use of PCT for sepsis and for pneumonia was approved in 2015 and 2022, respectively. This review will discuss the clinical utility of PCT on antibiotic stewardship in the management of sepsis and LRTIs including pneumonia.

The Role of Procalcitonin for Predicting Kawasaki Disease

Some studies have estimated the diagnostic value of procalcitonin (PCT) for Kawasaki disease (KD), but the results are not always consistent. The aim of this study was to ascertain the diagnostic value of PCT for KD. Relevant and eligible articles assessing the diagnostic significance of PCT in KD were systematically searched from PubMed as well as the CNKI databases (last update: October 31, 2020), followed by bivariate models to evaluate the overall diagnostic significance of PCT in KD. This systematic review and meta-analysis included four articles. The overall diagnostic specificity and sensitivity were 0.78 (95% CI: 0.74-0.82) and 0.73 (95% CI: 0.69-0.76), respectively. The area under the summary receiver operating characteristic (sROC) curve (AUC) was 0.82. The negative likelihood ratio (NLR) and positive likelihood ratio (PLR) values for PCT were 0.34 and 3.23, respectively. By analyzing the accessible articles, we showed PCT is not a particularly useful test for KD diagnosis.

Septic Shock: Management and Outcomes

The incidence rates of sepsis and septic shock as a complication have become more common over the past several decades. With this increase, sepsis remains the most common cause of intensive care unit (ICU) admissions and one of the most mortality factors, with a huge burden on healthcare facilities. Septic shock has devastating consequences on patients' lives, including organ failures and other long-term complications. Due to its dynamic clinical presentations, guidelines and tools have been established to improve the diagnosis and management effectively. However, there is still a need for evidence-based standardized procedures for the diagnosis, treatment, and follow-up of sepsis and septic shock patients due to the inconsistency of current guidelines and studies contrasting with each other. The standardization would help physicians better manage sepsis, minimize complications and reduce mortality. Septic shock is usually challenging to manage due to its variety of clinical characteristics and physiologic dynamics, affecting the outcomes. Therefore, this review presented the available data in the literature on septic shock diagnosis, management, and prognosis to have an overview of the updated best practice approach to septic shock.

Correlation between serum levels of PTX-3, SIL-2R, inflammatory markers, and APACHE II scores in patients with severe acute pancreatitis

To investigate the correlation of serum pentraxin 3 (PTX-3), soluble interleukin-2 receptor (SIL-2R), C-reactive protein (CRP), procalcitonin (PCT) levels, and acute physiology and chronic health evaluation II (APACHE II) scores in patients with severe acute pancreatitis (SAP). A total of 30 patients with SAP from October 2020 to October 2021 were selected as the SAP group, and 42 patients with mild acute pancreatitis (MAP) or moderate-severe acute pancreatitis (MSAP) was selected as the control group. The serum levels of PTX-3, SIL-2R, CRP, PCT, and APACHE II scores were evaluated. The serum levels of PTX-3, SIL-2R, CRP, PCT, and APACHE II scores at admission in the SAP group were significantly higher than those in the control group (all P < .05). Spearman analysis showed that serum PTX-3, SIL-2R, CRP, and PCT levels were positively correlated with APACHE II scores (all P < .05). The mortality rate within 28 days was 26.7% in the SAP group; moreover, the serum PTX-3, SIL-2R, CRP, and PCT levels and APACHE II scores at admission in the death group were significantly higher than those in the survival group (all P < .05). The receiver operating curve showed that the combined prediction value of all indicators (PTX-3 + SIL-2R + CRP + PCT + APACHE II) was superior to the single indicators, and the diagnostic sensitivity and specificity were 90.9% and 84.2%, respectively. Serum PTX-3, SIL-2R, CRP, and PCT levels and APACHE II scores have high guiding significance in early diagnosis and prognostic evaluation of SAP patients.

The Association between Admission Procalcitonin Level and The Severity of COVID-19 Pneumonia: A Retrospective Cohort Study

Background and Objectives: An elevated procalcitonin level has classically been linked to bacterial infections. Data on the association between elevated procalcitonin and the outcome of coronavirus disease 2019 (COVID-19) are conflicting. Some linked it to associated bacterial co-infections, while others correlated the elevation with disease severity without coexisting bacterial infections. We aimed to investigate the association between high procalcitonin and the severity of COVID-19. Materials and Methods: Hospitalized patients with confirmed COVID-19 pneumonia were divided into two groups: the normal-procalcitonin group and the high-procalcitonin group (>0.05 ng/mL). Patients with concomitant bacterial infections on admission were excluded. The primary outcomes were the need for intensive care unit (ICU) admission, progression to invasive mechanical ventilation (IMV), and in-hospital 28-day mortality. Results: We included 260 patients in the normal procalcitonin group and 397 patients in the high procalcitonin group. The mean age was 55 years and 49% were females. A higher number of patients in the elevated procalcitonin group required ICU admission (32.7% vs. 16.2%, p < 0.001) and IMV (27.2% vs. 13.5%, p < 0.001). In-hospital mortality was significantly higher in the elevated procalcitonin group (18.9% vs. 8.5%, p < 0.001). After adjusting for other covariates, procalcitonin > 0.05 ng/mL was an independent predictor of progression to IMV (OR, 1.71; 95% CI, 1.08−2.71; p = 0.022), ICU admission (OR, 1.73; 95% CI, 1.13−2.66; p = 0.011), and in-hospital mortality (OR, 1.99; 95% CI, 1.14−3.47; p = 0.015). An elevated procalcitonin level was the strongest predictor of in-hospital mortality. Conclusions: Measurement of procalcitonin can have a prognostic role among COVID-19 patients. The admission procalcitonin level can identify patients at risk of ICU admission, progression to IMV, and in-hospital mortality.

Serum Procalcitonin Levels in Newly Diagnosed Hodgkin Lymphoma: Correlation with Other Inflammatory Biomarkers

Background and Objectives: Procalcitonin (PCT) is a useful biomarker for the diagnosis of sepsis. Inflammatory markers are elevated in patients with Hodgkin lymphoma (HL), and yet ongoing infection rarely coexists at diagnosis. PCT levels might be helpful in differentiating bacterial from disease-related inflammation. Materials and Methods: We evaluated serum PCT levels and other inflammation markers in newly diagnosed HL patients. Values < 0.50 ng/mL were considered normal (0.10−0.50 ng/mL: detectable, <0.10 ng/mL: undetectable), while values ≥ 0.50 ng/L were considered elevated. Results: Among 137 patients, 55 had B symptoms (40%), 77/130 (59%) had elevated Erythrocyte Sedimentation Rate (ESR) and 116 (85%) had elevated C-Reactive Protein (CRP) (median 38.1 mg/L (range; 2.97−328)). PCT levels were normal in most patients (undetectable 94/137 (68.5%) and detectable 41/137(30%)) with median value < 0.10 ng/mL (range; <0.10−15.90). Elevated PCT was recorded in only two patients (1.5%). Patients with PCT < 0.10 ng/mL had significantly lower median CRP (25.75; range (2.97−203.0)) compared to patients with PCT ≥ 0.1 ng/mL (median CRP 92.50 mg/L; range (3.34−328.0)). Almost all patients (40/41, 97.6%) with detectable PCT had elevated CRP. Conclusions: This is the first study showing that the inflammation characterizing HL is not associated with PCT elevations, although CRP levels are elevated in 85% of the patients. Normal PCT levels may rule out the possibility of occult infection, thus preventing extensive evaluation, which may delay treatment initiation.

Procalcitonin as a predictive marker in COVID-19: A systematic review and meta-analysis

Background

Coronavirus disease 2019 has emerged as a global pandemic causing millions of critical cases and deaths. Early identification of at-risk patients is crucial for planning triage and treatment strategies.

Methods and findings

We performed this systematic review and meta-analysis to determine the pooled prognostic significance of procalcitonin in predicting mortality and severity in patients with COVID-19 using a robust methodology and clear clinical implications.

Design

We used Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Cochrane Handbook for Systematic Reviews of Interventions guidelines. We included thirty-two prospective and retrospective cohort studies involving 13,154 patients.

Results

The diagnostic odds ratio of procalcitonin for predicting mortality were estimated to be 11 (95% CI: 7 to 17) with sensitivity, specificity, and summary area under the curveof 0.83 (95% CI: 0.70 to 0.91), 0.69 (95% CI: 0.58 to 0.79), and 0.83 (95% CI: 0.79 to 0.86) respectively. While for identifying severe cases of COVID-19, the odds ratio was 8.0 (95% CI 5.0 to 12.0) with sensitivity, specificity, and summary area under the curve of 0.73 (95% CI 0.67 to 0.78), 0.74 (0.66 to 0.81), and 0.78 (95% CI 0.74 to 0.82) respectively.

Conclusion

Procalcitonin has good discriminatory power for predicting mortality and disease severity in COVID-19 patients. Therefore, procalcitonin measurement may help identify potentially severe cases and thus decrease mortality by offering early aggressive treatment.

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.

Procalcitonin Testing With Secondary Coinfection in Patients With COVID-19

Background

The coronavirus disease (COVID-19) virus has caused millions of deaths. It is difficult to differentiate between pure viral COVID-19 pneumonia and secondary infection. Clinicians often use procalcitonin (PCT) to decide on empiric antibiotic therapy.

Methodology

We performed a retrospective study of patients admitted with COVID-19 between January 1st, 2020, and June 30th, 2020. Patient demographics, clinical findings, and laboratory findings with a focus on PCT levels were recorded. Coinfection was considered if clinicians ordered a septic workup (urine, blood, and respiratory cultures) or if the physicians started or escalated antimicrobial therapy. PCT levels on the day of culture and daily for the next three days were recorded. Significant PCT change was defined as a decrease in PCT levels of >50% from the initial elevated PCT level.

Results

In total, 143 (59.8%) patients had one secondary infection. These included pulmonary infections (118, 49.4%), blood infections (99, 41.4%), and urine infections (64, 26.8%). Many patients had more than one documented positive culture: respiratory system and blood together in 80 (33.4%) patients, sputum and urine in 55 (23.1%) patients, and urine and blood in 46 (19.2%) patients. Out of the 143 patients with a positive culture, PCT was abnormal on the day of positive culture in 93 (65.5%), while PCT was abnormal in 64 out of 96 on the day of negative culture (66.7%) (p = 0.89). Individual analysis for PCT levels of respiratory cultures showed out of 118 positive sputum cultures, 86 (72%) had abnormal PCT on the day of culture. PCT in positive versus negative cultures was not significantly different, with median PCT (interquartile range, IQR) of 1.66 (6.61) versus 1.03 (2.23) (p = 0.172). For blood cultures, out of 99 positive blood cultures, 73 (73%) had abnormal PCT levels on the day of the culture. PCT in positive versus negative cultures was significantly elevated, with a median of 1.61 (5.97) vs. 0.65 (1.77) (p < 0.001). For urine, out of 64 positive cultures, 41 (64.1%) had abnormal PCT levels on the day of the culture. PCT in positive versus negative cultures was not significantly different, with a median of 0.71 (2.92) vs. 0.93 (4.71) (p = 0.551). To observe the change in PCT after culture, PCT values for the next three days after culture were analyzed. We found that patients with positive cultures had higher PCT levels than those with negative cultures. There was no significant improvement over the following three days. Patients with abnormal PCT on the day of the suspected infection had a longer length of stay in the hospital, with a median (IQR) of 23.9 days (3.16) vs. 16.9 days (2.18) (p = 0.021).

Conclusions

Secondary coinfections in patients with COVID-19 infections are not associated with PCT elevation on the day of suspected secondary infection. However, most patients with bacteremia had a significant elevation of PCT on the day of bacteremia before collection and reporting of positive culture. Patients with abnormal PCT levels on the day of suspected infection had a longer hospital stay than patients with normal PCT levels. Subsequent testing of PCT in patients showed no significant improvement in PCT.

The Sustained and Marked Elevation of Serum Procalcitonin in a Hemodialysis Patient with Tuberculous Lymphadenitis, but Without the Evidence of Sepsis: A Case Report

Background

The elevation of serum procalcitonin (PCT) has been considered as a marker of systemic bacterial infection and sepsis. However, the marked elevation of PCT in non-sepsis conditions was rare. Here, we report a rare case of sustained markedly elevation of serum PCT in a dialysis patient with tuberculosis, but without the evidence of sepsis.

Case Presentation

A 25-year-old man on maintenance hemodialysis was admitted to the hospital for kidney transplantation. On admission, physical examination revealed multiple lymph nodes were palpable on both sides of the neck which was later confirmed as tuberculosis with biopsy pathology. On the 3rd day after admission, the patient suffered from fever with a temperature of 38.8°C. The white blood cells 12.35 × 10⁹/L and the PCT level was 5.73 ng/mL. Lately the PCT increased to 63.10 ng/mL, and the level of C-reactive protein was 186.00 mg/L. After the antibiotics upgraded from cefmetazole to meropenem, and vancomycin was added, the body temperature dropped to the normal range on the 17th day and remained normal thereafter. The PCT level declined gradually to 4.18 ng/mL on the 21st day and an antituberculosis regimen was started. After that, the PCT levels fluctuated between 2.9 ng/mL and 94.9 ng/mL without any manifestation of sepsis. The markedly elevation of serum PCT level persisted despite normal C-reactive protein level and leukocyte counts.

Conclusion

Persistently elevated serum PCT level might occur in conditions without evidence of sepsis. Taking consideration of multiple inflammatory factors to determine infection when the markedly elevated PCT level was not correlated with the clinical manifestations.

Procalcitonin mediates vascular dysfunction in obesity

AIMS

Obesity is accompanied by a chronic low-grade inflammation associated with endothelial dysfunction and vascular complications. Procalcitonin is a marker of inflammation, secreted by adipose tissue and elevated in obese subjects. We here investigated whether visceral or perivascular fat-derived procalcitonin is a target to improve obesity-induced endothelial dysfunction.

MATERIALS AND METHODS

Procalcitonin expression was identified by Western blot. Murine endothelial cells were isolated using CD31-antibody-coated magnetic beads and reactive oxygen species and nitric oxide (NO) determined by H2DCF- or DAF-FM diacetate loading. Endothelium-dependent vasorelaxation was analyzed using pressure myography of murine arterioles. Calcitonin gene-related peptide (CGRP) was used to activate the calcitonin receptor-like receptor (CRLR)/RAMP1 complex and olcegepant or the dipeptidyl-peptidase 4 (DPP4) inhibitor sitagliptin to block procalcitonin signaling or activation.

KEY FINDINGS

In addition to visceral adipose tissue, procalcitonin was present in perivascular and epicardial tissue. In concentrations typical for obesity, procalcitonin doubled reactive oxygen species formation and decreased endothelial nitric oxide production in murine endothelial cells. Intravenous delivery of procalcitonin to mice in obesity-associated concentrations impaired endothelium-dependent vasorelaxation in a CRLR/RAMP1-dependent manner and antagonized CGRP-induced endothelial NO release in vitro. Use of CRLR/RAMP1-receptor antagonist olcegepant counteracted procalcitonin effects on vasodilation, nitric oxide production and reactive oxygen species formation. Similarly, blocking procalcitonin activation by the DPP4 inhibitor sitagliptin antagonized endothelial procalcitonin effects.

SIGNIFICANCE

Procalcitonin, liberated either from visceral or perivascular adipose tissue, contributes to endothelial dysfunction by antagonizing CGRP signaling in obesity. Targeting hyperprocalcitonemia may be a means to preserve endothelial function and reduce comorbidity burden in obese subjects.

Occurrence and outcomes of possible superadded infections in older adults with COVID-19-cohort study

Aim

To investigate the outcomes and prevalence of superadded infections in older adults with COVID-19.

Findings

Possible superadded infection is common in older adults hospitalized with COVID-19 and was associated with longer inpatient stay and higher mortality.

Message

Clinicians should have a low threshold to assess for other sources of infection in older adults with COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-022-00675-9.

Purpose

Current guidance discourages use of antibiotics in COVID-19. However, in older adults, superadded infection may be common and require treatment. Our aim was to investigate the occurrence and outcomes from possible superadded infections, occurring within 2 weeks of hospitalization, in older adults with COVID-19.

Methods

This was a single centre, observational cohort study. We collected data from patients admitted to older adult wards who had tested positive for the Sars-CoV-2 virus on viral PCR between 1st October and 1st December 2020. The primary outcome was inpatient death occurring within 90 days of COVID-19 diagnosis. The secondary outcome was length of stay in hospital. Associations were described using univariable and multivariable models, and time to event data.

Results

Of 266 patients with COVID-19, 43% (115) had evidence of superadded infections (91 with positive bacterial cultures and 36 instances of radiological lobar consolidation). Patients with superadded infections were more likely to die (45.2 versus 30.7%, p = 0.020) and had an increased length of stay (23 versus 18 days, p = 0.026).

Conclusions

Recommendations to avoid antibiotics in COVID-19 may not be applicable to an older adult population. Assessing for possible superadded infections is warranted in this group.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-022-00675-9.

Extra-pulmonary applications of procalcitonin: an updated literature review

INTRODUCTION

: Procalcitonin (PCT) is a biomarker with established performance in the differentiation between bacterial and viral infections, predominantly in pulmonary infections, as well as the diagnosis and prognosis of bacterial sepsis. However, the role of PCT in extra-pulmonary infections is not well described.

AREAS COVERED

: We reviewed the role of PCT in commonly experienced extra-pulmonary infections including meningitis, diabetic foot infection, prosthetic joint infection, osteomyelitis, and skin and soft tissue infection. PubMed and Medline online libraries were searched, from 2013 till 2022, for relevant articles.

EXPERT OPINION

: For meningitis, PCT could distinguish bacterial from viral meningitis. PCT distinguished septic arthritis from different types of arthritis but had variable performance in discriminating septic arthritis from crystal arthropathy. For periprosthetic joint infections, results were inconclusive. PCT had a potential role in diagnosis of more complex infections such as osteomyelitis and diabetic foot infections, but further studies are needed for a definitive cutoff. In skin and soft tissue infections, PCT performance was more variable requiring further investigation to define cutoff for the discrimination of cellulitis from necrotizing fasciitis. We find that PCT performed best for meningitis and helps in the reduction of unnecessary antibiotic treatment, but has variable outcomes with other extra-pulmonary infections.

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.

Optimization of flow path parameters for enhanced sensitivity lateral flow devices

Lateral flow devices (LFDs) or lateral flow tests (LFTs) are one of the most widely used biosensor platforms for point-of-care (POC) diagnostics. The basic LFD design has remained largely unchanged since its first appearance, and this has limited LFD use in clinical applications due to a general lack of analytical sensitivity. We report here a comprehensive study of the use of laser-patterned geometric control barriers that influence the flow dynamics within an LFD, with the specific aim of enhancing LFD sensitivity and lowering the limit of detection (LOD). This control of sample flow produces an increase in the time available for optimizing the binding kinetics of the implemented assay. The geometric modification to the flow path is in the form of a constriction that is produced by depositing a photo-sensitive polymer onto the nitrocellulose membrane which when polymerized, creates impermeable barrier walls through the depth of the membrane. Both the position of the constriction within the flow path and the number of constrictions allow for an increase in the sensitivity because of a slower overall flow rate within the test and a larger volume of sample per unit width of the test line. For these high sensitivity LFDs (HS-LFD), through optimization of the constriction position and addition of a second constriction we attained a 62% increase in test line color intensity for the detection of procalcitonin (PCT) and were also able to lower the LOD from 10 ng/mL to 1 ng/mL. In addition, of relevance for future commercial exploitation, this also significantly decreases the antibody consumption per device leading to reduced costs for test production. We have further tested our HS-LFD with contrived human samples, validating its application for future clinical use.

The efficacy of inflammatory markers in diagnosing infected diabetic foot ulcers and diabetic foot osteomyelitis: Systematic review and meta-analysis

Background

Diabetes foot ulcer (DFU) is a complication of diabetes mellitus. Accurate diagnosis of DFU severity through inflammatory markers will assist in reducing impact on quality of life. We aimed to ascertain the diagnostic test accuracy of commonly used inflammatory markers such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin (PCT), and white cell count (WCC) for the diagnosis and differentiation between DFU grades based on the International Working Group on the Diabetic Foot classification system.

Methods

This systematic review explored studies that investigated one or more of the above-listed index tests aiding in diagnosing infected DFU. This review was registered on PROSPERO database (ID = CRD42021255618) and searched 5 databases including an assessment of the references of included studies. Records were manually screened as per Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A total of 16 studies were included which were assessed for quality using QUADAS-2 tool and meta-analysed using Meta-Disc v1.4.

Results

CRP had the greatest area under the curve (AUC) of 0.893 for diagnosing grade 2 DFU. This returned a pooled sensitivity and specificity of 77.4% (95% CI: 72% to 82%) and 84.3% (95% CI: 79% to 89%) respectively. In terms of diagnosing grade 3 DFU, procalcitonin had the highest AUC value of 0.844 when compared with other markers. The pooled sensitivity of PCT was calculated as 85.5% (95% CI: 79% to 90%) and specificity as 68.9% (95% CI: 63% to 75%).

Conclusion

CRP and PCT are the best markers for diagnosing grade 2 and grade 3 DFU respectively. Other markers are also valuable when used in conjunction with clinical judgement. The findings accentuate the necessity of further research to establish standardised cut-off values for these inflammatory markers in diagnosing diabetic foot ulcers.

Heparin Binding Protein for the Early Diagnosis and Prognosis of Sepsis in the Emergency Department: The Prompt Multicenter Study

BACKGROUND

The validation of new biomarkers for the diagnosis and risk stratification of patients with sepsis at an early point is essential for successful treatment. Recent publications prompted us to investigate of heparin binding protein (HBP) for the emergency department (ED) admissions.

MATERIALS AND METHODS

In this multicenter, cross-sectional study, HBP and procalcitonin (PCT) were measured within the first hour upon admission to the ED in plasma samples of 371 patients with signs of infection. Patients were classified into non-sepsis and sepsis by the Sepsis-3 definitions and were followed up for outcome.

RESULTS

HBP was significantly higher in patients with sepsis and was positively correlated to PCT and C-reactive protein, absolute neutrophil and monocyte counts, creatinine, bilirubin and lactate. Sensitivity, specificity, positive predictive value, and negative predictive value of HBP more than 19.8 ng/mL for the diagnosis of sepsis was 66.3%, 44.9%, 49.3%, and 62.2%, respectively; and for prediction of early death was 100%, 41.0%, 4.5%, and 100%, respectively. Single HBP and PCT could not predict 28-day mortality; this was performed with sensitivity, specificity, positive predictive value, and negative predictive value 44.8%, 81.8%, 17.3%, and 94.6% when used in combination.

CONCLUSION

Admission HBP can be used as a tool for the early diagnosis of sepsis and for the risk of early death in the ED.

Related Markers for the Precision Diagnosis of Complex Appendicitis in Children

Acute appendicitis is the most common surgical emergency in children. Despite the high incidence rate of appendicitis, it is sometimes misdiagnosed or missed. Complex appendicitis (CA) in children is characterized by a critical condition, several complications, and high mortality. Precision distinguishing between simple appendicitis and CA correctly is key to choosing appropriate treatment. A safe, cheap, rapid, extensive and accurate diagnostic marker of appendicitis will be of great significance for emergency general surgeons to treat suspected CA. Many studies have investigated possible diagnostic markers for the diagnosis of CA in children. In this study, studies related to CA in children in recent years are summarized, and the related markers and scoring system for the diagnosis of CA in children are summarized.

Procalcitonin levels in children affected by severe malaria compared to those with uncomplicated malaria in the absence of bacterial infection: a cross-sectional study

BACKGROUND

Procalcitonin is an inflammatory marker strongly associated with the presence of bacterial infection. It has been considered raised in severe malaria infection as opposed to uncomplicated malaria. There are suggestions that it may be raised only when there is concomitant unnoticeable bacterial infection during a malaria crisis. We aimed to assess the difference in plasma procalcitonin levels between children affected by severe and uncomplicated malaria.

METHODS

We assessed plasma procalcitonin levels in 83 children diagnosed with malaria with no clinical and biological evidence of concomitant bacterial infection. Severity of malaria was established using WHO guidelines. Procalcitonin was determined using the ELISA method. Non-parametric Mann-Whitney U test was used to compare medians across the 2 groups. Statistical significance was set for all p values < 0.05.

RESULTS

Of the 83 participants, 28 had uncomplicated malaria, and 55 had severe malaria. PCT levels were obtained in 24 and 40 subjects of each group, respectively, and were similar in both groups; [2.76 (2.52-2.93) vs 2.74 (2.52-2.98) ng/ml, p = 0.916]. The parasite density was lower in the uncomplicated malaria group than in the severe malaria group, but not statistically significant; [22,192 (9110-44 654) vs 31 684 (13 960-73 500) parasites/μl, p = 0.178]. There was no correlation between the parasite density in the general study population and PCT levels (r = 0.072, p = 0.572).

CONCLUSION

In the absence of overt bacterial infection, procalcitonin levels are not different between children affected with uncomplicated malaria and those with severe malaria. Therefore, bacterial infection should be thoroughly checked for in children with raised serum procalcitonin diagnosed with severe malaria.

Drug-induced interstitial lung disease during cancer therapies: expert opinion on diagnosis and treatment

Background

Drug-induced interstitial lung disease (DIILD) is a form of interstitial lung disease resulting from exposure to drugs causing inflammation and possibly interstitial fibrosis. Antineoplastic drugs are the primary cause of DIILD, accounting for 23%-51% of cases, with bleomycin, everolimus, erlotinib, trastuzumab-deruxtecan and immune checkpoint inhibitors being the most common causative agents. DIILD can be difficult to identify and manage, and there are currently no specific guidelines on the diagnosis and treatment of DIILD caused by anticancer drugs.

Objective

To develop recommendations for the diagnosis and management of DIILD in cancer patients.

Methods

Based on the published literature and their clinical expertise, a multidisciplinary group of experts in Italy developed recommendations stratified by DIILD severity, based on the Common Terminology Criteria for Adverse Events.

Results

The recommendations highlight the importance of multidisciplinary interaction in the diagnosis and management of DIILD. Important components of the diagnostic process are physical examination and careful patient history-taking, measurement of vital signs (particularly respiratory rate and arterial oxygen saturation), relevant laboratory tests, respiratory function testing with spirometry and diffusing capacity of the lung for carbon monoxide and computed tomography/imaging. Because the clinical and radiological signs of DIILD are often similar to those of pneumonias or interstitial lung diseases, differential diagnosis is important, including microbial and serological testing to exclude or confirm infectious causes. In most cases, management of DIILD requires the discontinuation of the antineoplastic agent and the administration of short-term steroids. Steroid tapering must be undertaken slowly to prevent reactivation of DIILD. Patients with severe and very severe (grade 3 and 4) DIILD will require hospitalisation and often need oxygen and non-invasive ventilation. Decisions about invasive ventilation should take into account the patient’s cancer prognosis.

Conclusions

These recommendations provide a structured step-by-step diagnostic and therapeutic approach for each grade of suspected cancer-related DIILD.

•

There is a lack of guidance for the management of DIILD in cancer patients.

•

A multidisciplinary team in Italy developed step-by-step diagnostic and therapeutic guidelines for DIILD in cancer patients.

•

Differential diagnosis of DIILD is critical to exclude other forms of interstitial lung disease or infectious causes.

•

Usually the antineoplastic agent is discontinued, steroids started and further management dictated by DIILD severity.

Real-Time Monitoring of Biomolecules: Dynamic Response Limits of Affinity-Based Sensors

Sensors for monitoring biomolecular dynamics in biological systems and biotechnological processes in real time, need to accurately and precisely reconstruct concentration–time profiles. This requirement becomes challenging when transport processes and biochemical kinetics are important, as is typically the case for biomarkers at low concentrations. Here, we present a comprehensive methodology to study the concentration–time profiles generated by affinity-based sensors that continuously interact with a biological system of interest. Simulations are performed for sensors with diffusion-based sampling (e.g., a sensor patch on the skin) and advection-based sampling (e.g., a sensor connected to a catheter). The simulations clarify how transport processes and molecular binding kinetics result in concentration gradients and time delays in the sensor system. Using these simulations, measured and true concentration–time profiles of insulin were compared as a function of sensor design parameters. The results lead to guidelines on how biomolecular monitoring sensors can be designed for optimal bioanalytical performance in terms of concentration and time properties.