Diagnoses Based on C-Reactive Protein Point-of-Care Tests

Analysis of early warning indicators of death in patients with severe fever with thrombocytopenia syndrome

BACKGROUND

Since its discovery, severe fever with thrombocytopenia syndrome (SFTS) has been characterized by rapid progression and poor prognosis, and no specific treatment is available. The aim of this study was to investigate the early warning indicators of mortality in SFTS patients.

METHODS

This is a retrospective cross-sectional study. The study subjects were patients who were admitted to the hospital with a confirmed diagnosis of SFTS from January 2023 to October 2023, and their clinical symptoms and signs at the time of admission, as well as the laboratory indexes of the first blood collection after admission were collected, grouped according to the prognosis, and statistically analyzed.

RESULTS

A total of 141 patients were collected, of which 27 patients died and 114 patients were in the survival group. Through statistical analysis, patients with combined hemorrhagic manifestations, disturbance of consciousness, lymphopenia, elevated lipase, and prolonged thrombin time on admission were independent risk factors for patients' death. By plotting the working characteristic curve of the subjects, as well as calculating the area under the curve, the results showed that the AUC of lymphopenia count was 0.670, 95% CI (0.563-0.776), P = 0.006; the AUC of elevated serum lipase index was 0.789, 95% CI (0.699-0.878), p < 0.001; the AUC of prolonged thrombin time was 0.749, 95% CI (0.645-0.854), p < 0.001.

CONCLUSION

Patients with hemorrhagic manifestations, disturbance of consciousness, lymphocyte reduction, elevated serum lipase, and prolonged thrombin time on admission are more worthy of the clinician's attention, and require early and effective interventions to avoid further disease progression.

Rapid Microfluidic Immuno-Biosensor Detection System for the Point-of-Care Determination of High-Sensitivity Urinary C-Reactive Protein

A microfluidic immuno-biosensor detection system consisting of a microfluidic spectrum chip and a micro-spectrometer detection device is presented for the rapid point-of-care (POC) detection and quantification of high-sensitivity C-reactive protein (hs-CRP) in urine. The detection process utilizes a highly specific enzyme-linked immunosorbent assay (ELISA) method, in which capture antibodies and detection antibodies are pre-deposited on the substrate of the microchip and used to form an immune complex with the target antigen. Horseradish peroxidase (HRP) is added as a marker enzyme, followed by a colorimetric reaction using 3,3',5,5'-tetramethylbenzidine (TMB). The absorbance values (a.u.) of the colorimetric reaction compounds are measured using a micro-spectrometer device and used to measure the corresponding hs-CRP concentration according to the pre-established calibration curve. It is shown that the hs-CRP concentration can be determined within 50 min. In addition, the system achieves recovery rates of 93.8-106.2% in blind water samples and 94.5-104.6% in artificial urine. The results showed that the CRP detection results of 41 urine samples from patients with chronic kidney disease (CKD) were highly consistent with the conventional homogeneous particle-enhanced turbidimetric immunoassay (PETIA) method's detection results (R2 = 0.9910). The experimental results showed its applicability in the detection of CRP in both urine and serum. Overall, the results indicate that the current microfluidic ELISA detection system provides an accurate and reliable method for monitoring the hs-CRP concentration in point-of-care applications.

Axial Spondyloarthritis Treatment Recommendations and Disease Activity Monitoring in Clinical Practice: Results of an Online Survey

OBJECTIVE

Clinical practice guidelines are not always followed consistently. To better understand potential barriers to the implementation of treatment recommendations in axial spondyloarthritis and ankylosing spondylitis (axSpA/AS), an online survey was conducted.

METHODS

Email invitations were sent to US rheumatology care providers in January 2023. The questionnaire included 20 questions, with an estimated completion time of 5-7 minutes.

RESULTS

One hundred four of 441 (24%) invitees participated, including 80/104 (77%) board-certified rheumatologists and 20/104 (19%) fellows. Survey participants identified UpToDate (85%), treatment guidelines (74%), and colleagues (54%) as relevant sources of knowledge for managing axSpA/AS. Of the participants, 64% and 53% considered themselves to be at least moderately familiar with the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network (ACR/SAA/SPARTAN) and Assessment of Spondyloarthritis international Society/European Alliance of Associations for Rheumatology (ASAS/EULAR) treatment recommendations for axSpA/AS, respectively. Whereas 69% of participants agreed or strongly agreed that disease activity scores are useful for making treatment decisions in axSpA/AS, only 37% measure patient-reported outcomes (PROs) frequently (≥ 50% of clinic visits) while 82% do so for C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). PROs are typically recorded during clinic encounters (65%) and CRP/ESR are obtained after the visit (86%). Of the participants, 57% and 47% considered the Bath Ankylosing Spondylitis Disease Activity Index and Ankylosing Spondylitis Disease Activity Score to be at least moderately useful for measuring disease activity in axSpA/AS, respectively; 41% and 37% thought the same about the ASAS 20% improvement criteria and Clinical Disease Activity Index, respectively.

CONCLUSION

Treatment guidelines are an important resource for rheumatologists who manage patients with axSpA/AS. Although there is general agreement that disease activity monitoring is important, the implementation of the respective recommendations is lacking. Reasons may include lack of familiarity and an underdeveloped infrastructure to efficiently collect PROs.

Evaluation of a new point-of-care diagnostic test measuring inflammation in emergency settings

Erythrocyte aggregation kinetics is accelerated in diseases with a strong inflammation component. This study aimed to evaluate whether, in an emergency setting, a new point-of-care test measuring erythrocyte aggregation kinetics (EAK) can identify patients with underlying inflammation. Patients visiting an emergency department and needing a blood exam were successively included. EAK was measured at the point-of-care in 20 s directly on the blood samples collected in regular tubes without any manipulation. The primary measure was EAK's half-life during the first 5 s (EAK5s). Each patient's inflammation status was assessed blind to the EAK test results. Receiver Operating Characteristic (ROC) curves for inflammation status were built. 268 patients had their EAK5s measured, and a clear inflammation status was determined for 214 patients (65 had inflammation). Mean EAK5s were 2.18 s and 1.75 s for no inflammation and inflammation groups respectively (p < 0.001). EAK5s appears to be a better inflammation marker than C-Reactive protein (CRP), with an area under the ROC curve of 0.845 compared to 0.806 for CRP (p < 0.0001). The Youden threshold for prediction of inflammation was 1.86 s with 84.6% (78.5-89.9%) specificity and 70.8% (60-81.5%) sensitivity. Point-of-care EAK is an easily measured, immediately available marker of inflammation with a better predictive power than CRP's.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Investigation of Peptides for Molecular Recognition of C-Reactive Protein-Theoretical and Experimental Studies

We investigate the interactions between C-reactive protein (CRP) and new CRP-binding peptide materials using experimental (biological and physicochemical) methods with the support of theoretical simulations (computational modeling analysis). Three specific CRP-binding peptides (P2, P3, and P9) derived from an M13 bacteriophage have been identified using phage-display technology. The binding efficiency of the peptides exposed on phages toward the CRP protein was demonstrated via biological methods. Fibers of the selected phages/peptides interact differently due to different compositions of amino acid sequences on the exposed peptides, which was confirmed by transmission electron microscopy. Numerical and experimental studies consistently showed that the P3 peptide is the best CRP binder. A combination of theoretical and experimental methods demonstrates that identifying the best binder can be performed simply, cheaply, and fast. Such an approach has not been reported previously for peptide screening and demonstrates a new trend in science where calculations can replace or support laborious experimental techniques. Finally, the best CRP binder─the P3 peptide─was used for CRP recognition on silicate-modified indium tin oxide-coated glass electrodes. The obtained electrodes exhibit a wide range of operation (1.0-100 μg mL-1) with a detection limit (LOD = 3σ/S) of 0.34 μg mL-1. Moreover, the dissociation constant Kd of 4.2 ± 0.144 μg mL-1 (35 ± 1.2 nM) was evaluated from the change in the current. The selectivity of the obtained electrode was demonstrated in the presence of three interfering proteins. These results prove that the presented P3 peptide is a potential candidate as a receptor for CRP, which can replace specific antibodies.

Antibody-Conjugated Nanodiamonds as Dual-Functional Immunosensors for In Vitro Diagnostics

Nanodiamonds (NDs) are carbon nanoparticles with a large refractive index, a high density, and exceptional chemical stability. When excited by green light, they can emit bright red fluorescence from implanted nitrogen-vacancy (NV) centers. Taking advantage of these properties, we have developed antibody-conjugated NDs as in vitro diagnostic sensors for two complementary assays: particle-enhanced turbidimetric immunoassay (PETIA) and spin-enhanced lateral flow immunoassay (SELFIA). To achieve this goal, monocrystalline diamond powders (∼100 nm in diameter) with or without NV implantation were first treated in molten KNO3 to reduce their size and shape inhomogeneity, followed by surface carboxylation in strong oxidative acids and non-covalent conjugation with antibodies in water. PETIA and SELFIA were carried out separately with a microplate reader and a magnetically modulated fluorescence analyzer. Using C-reactive protein (CRP) as the target antigen, we found that anti-CRP-conjugated NDs exhibited high colloidal stability over 1 month at 4 °C in buffer solution. The limits of detection for 3 μL of CRP sample solution were 0.06 μg/mL and 1 ng/mL with variation coefficients of less than 10 and 15% for PETIA and SELFIA, respectively. These two methods together provide a detection range of 1 ng/mL-10 μg/mL, potentially useful for clinical applications. This work represents the first practical use of rounded monocrystalline NDs as in vitro diagnostic reagents.

Assessment of Changes in Serum C-Reactive Protein Levels in Patients after Ischemic Stroke Undergoing Rehabilitation-A Retrospective Observational Study

Inflammation plays a key role in the pathogenesis and prognosis of ischemic stroke. C-reactive protein (CRP) is an inflammatory biomarker of inflammation and may reflect the progression of vascular disease. Using a biomarker such as CRP to predict recovery rather than mortality may present clinical value in providing rehabilitation. The primary aim of the study was to analyze changes in serum CRP levels in patients after ischemic stroke during the regenerative-compensatory period and to assess the usefulness of CRP as a potential biomarker during the rehabilitation period. The project was carried out as a retrospective analysis of prospectively collected data from post-stroke patients from the Department of Neurological Rehabilitation of the Regional Specialist Hospital in Wrocław. A group of 52 patients, after their first-ever ischemic stroke with subsequent hemiplegia, was finally qualified to participate in the study. Serum CRP levels were determined during blood laboratory tests. The Modified Rankin Scale (mRS) and Barthel Index (BI) were used to assess functional outcomes. Rehabilitation using neurophysiological methods was applied five days a week (each session lasted 60 min, and the entire period was 42 days). At the first test, serum CRP levels were found to be above 5 mg/L in 19 patients, the second test in 12 patients, the third test in five patients, and the fourth test in 9 patients. Only three patients had values higher than 5 mg/L in all consecutive assessments (p > 0.05). There was a statistically significant increase in BI scores after therapy (p < 0.001) as well as a decrease in the mRS score by 2.2 points (p < 0.001), in CRP values by 5.02 mg/L (p = 0.019), and in cortisol levels by 2.5 nmol/L (p = 0.002). Statistically significant relationships were observed between the CRP levels after rehabilitation and the corresponding mRS scores (rs = 0.29, p = 0.038). Furthermore, the effect of BMI on CRP levels was demonstrated (B = 0.20, p = 0.038). In conclusion, despite demonstrating a significant relationship between CRP levels and corresponding mRS scores, CRP levels alone may not serve as an independent predictor of long-term functional outcomes in ischemic stroke patients undergoing rehabilitation.

Detection of COVID-19-related biomarkers by electrochemical biosensors and potential for diagnosis, prognosis, and prediction of the course of the disease in the context of personalized medicine

As a more efficient and effective way to address disease diagnosis and intervention, cutting-edge technologies, devices, therapeutic approaches, and practices have emerged within the personalized medicine concept depending on the particular patient's biology and the molecular basis of the disease. Personalized medicine is expected to play a pivotal role in assessing disease risk or predicting response to treatment, understanding a person's health status, and, therefore, health care decision-making. This work discusses electrochemical biosensors for monitoring multiparametric biomarkers at different molecular levels and their potential to elucidate the health status of an individual in a personalized manner. In particular, and as an illustration, we discuss several aspects of the infection produced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a current health care concern worldwide. This includes SARS-CoV-2 structure, mechanism of infection, biomarkers, and electrochemical biosensors most commonly explored for diagnostics, prognostics, and potentially assessing the risk of complications in patients in the context of personalized medicine. Finally, some concluding remarks and perspectives hint at the use of electrochemical biosensors in the frame of other cutting-edge converging/emerging technologies toward the inauguration of a new paradigm of personalized medicine.