Use of plasma osteocalcin as a biomarker in the preparation of a product for the diagnosis and / or prognosis of sepsis in children

Abstract

The present application relates to the use of plasma osteocalcin as a biomarker in the preparation of a diagnostic and / or prognostic product for sepsis in children. The prognostic product uses the measurement of osteocalcin levels on the first day of admission of a child with sepsis to assess the degree of organ dysfunction and the need for organ support in patients with sepsis. The present application discloses the potential of osteocalcin as a modulator of the immune inflammatory response in sepsis and that its level changes can be used as a predictive marker of the diagnosis and clinical outcome of sepsis. This finding provides a new biomarker for the early diagnosis, prognosis evaluation and treatment of sepsis and an important basis for clinical management.

Description

Technical Field

[0001] This invention relates to the application of plasma osteocalcin as a biomarker in the preparation of diagnostic and / or prognostic products for childhood sepsis, and belongs to the field of biomedical technology. Background Technology

[0002] Sepsis is a multi-organ dysfunction caused by a dysregulated host response to infection. It is a common cause of admission to pediatric intensive care units (PICUs) worldwide and plays a significant role in the global disease burden. Studies indicate that sepsis causes approximately 11 million deaths annually, with more than half of these cases occurring in children. The clinical challenges of childhood sepsis lie in its rapid onset, progression, atypical clinical symptoms, and difficulty in early identification, leading to delayed treatment and a persistently high mortality rate.

[0003] The immune response in sepsis is complex and dysregulated. Initially, the immune system is activated to clear pathogens, accompanied by a "cytokine storm." However, as the disease progresses, the immune response becomes overactivated and then suppressed, failing to effectively clear pathogens and instead triggering systemic inflammation, leading to organ failure and high mortality. In the clinical diagnosis and treatment of sepsis, existing biomarkers and assessment tools have significant limitations. Traditional biomarkers such as procalcitonin (PCT) have some specificity for bacterial infections, but they can also be abnormally elevated in viral infections and non-infectious inflammations, and their dynamic changes are complex and difficult to accurately reflect real-time disease progression. C-reactive protein (CRP), while highly sensitive, lacks specificity and cannot effectively distinguish the source of infection or predict organ dysfunction. Interleukin-6 (IL-6), as a pro-inflammatory cytokine, indicates a poor prognosis when its levels are elevated, but its short half-life and demanding detection techniques limit its clinical application. Meanwhile, clinically applied organ dysfunction scoring systems also have significant shortcomings: the Pediatric Multiple Organ Dysfunction Score (P-MODS), designed specifically for children, covers the assessment of dysfunction in six major systems, but its data collection is complex and time-consuming, lacks real-time performance, and is often calculated based on the worst value within 24 hours, failing to reflect real-time changes in the patient's condition. Furthermore, parameters such as neurological assessments are subject to subjective judgment differences, and the score only increases significantly when organ dysfunction is evident, limiting its early warning value. The Pediatric Logical Organ Dysfunction Score-2 (PELOD-2), designed specifically for PICU patients, includes assessments of five organ systems, but its calculation formula is complex, difficult for clinicians to master, unsuitable for frequent repeated assessments to track real-time changes in the patient's condition, and some parameters rely on laboratory tests, leading to delayed results. The normal ranges for children of different ages vary greatly, and adjusting the scoring criteria is cumbersome. The Pediatric Sequential Organ Failure Assessment (pSOFA) score has been well validated in adults, but specific validation studies in children are limited, the cutoff values ​​are unclear, and the broad pediatric normal ranges for some parameters reduce the sensitivity of the score. It is usually only used for admission assessment, and its dynamic predictive value needs further validation. These biomarkers and scoring systems share a common set of limitations, including insufficient early identification capabilities, difficulty in dynamic monitoring, limited predictive specificity, poor operational practicality, and low cost-effectiveness. Most indicators only show significant abnormalities when organ dysfunction is evident, missing the optimal intervention window. Scoring systems are computationally complex and unsuitable for frequent assessments. Traditional biomarker changes are complex and difficult to interpret, making it hard to accurately distinguish the severity of sepsis, the risk of organ dysfunction, and mortality. Multiple tests and complex calculations are required, which are difficult to implement in primary hospitals. Multiple tests increase medical costs but offer limited clinical benefits.

[0004] Osteocalcin, also known as bone γ-carboxyglutamate protein (BGP), is a non-collagenous protein synthesized and secreted by osteoblasts, accounting for 10-20% of the non-collagenous proteins in the bone matrix. Traditionally, osteocalcin has been considered a specific marker of bone formation for assessing bone metabolism. However, recent studies have revealed its important endocrine functions, not only participating in bone mineralization and metabolic regulation but also exerting hormone-like effects through its uncarboxylated form, influencing multiple physiological processes such as energy metabolism regulation, insulin sensitivity, male reproduction, cognitive function, and muscle function. Osteoblasts are not only bone-forming cells but also secrete various cytokines and chemokines involved in immune regulation. As an important product of osteoblasts, osteocalcin may participate in the immune regulation of sepsis through the osteoo-immune axis. In vitro studies have shown that osteocalcin can regulate macrophage function, affect the secretion of pro-inflammatory factors such as TNF-α and IL-6, and may participate in adaptive immune responses by regulating T cell differentiation and function. In sepsis, impaired osteoblast function and reduced osteocalcin synthesis may have a feedback effect on the systemic inflammatory state. Sepsis is often accompanied by severe metabolic disorders, including insulin resistance, hyperglycemia, and muscle wasting. Sepsis-related muscle atrophy may be related to impaired osteocalcin metabolism regulation, and its endocrine function may affect the functional coordination of multiple organ systems. A deeper understanding of the correlation between plasma osteocalcin levels and clinical outcomes in children with sepsis may provide a scientific basis for supplementing existing sepsis biomarkers and clinical scoring systems, thereby guiding clinical diagnosis and treatment. Summary of the Invention

[0005] The purpose of this invention is to provide a biomarker based on plasma osteocalcin levels for the diagnosis and prognostic assessment of childhood sepsis, addressing the issues of early diagnosis and prognostic assessment of childhood sepsis.

[0006] To achieve the above objectives, this invention provides the application of plasma osteocalcin as a biomarker in the diagnosis and prognosis of sepsis in children. The plasma osteocalcin level can be used to assess the degree of organ dysfunction in children with sepsis and to preliminarily determine whether organ support is required. Studies have shown that compared with healthy children and children with mild infection, the concentration of osteocalcin in the plasma of children with sepsis is significantly reduced in the early stages of sepsis, and the level of reduction is correlated with whether the children with sepsis require organ support.

[0007] In one aspect, this application provides the use of osteocalcin in the preparation of diagnostic and / or prognostic products for childhood sepsis.

[0008] Furthermore, the application of osteocalcin in the preparation of prognostic products for pediatric sepsis refers to measuring osteocalcin levels on the first day of hospitalization for sepsis patients to assess the degree of organ dysfunction and whether organ support is required.

[0009] Furthermore, the product is a reagent kit.

[0010] Secondly, this application provides a prognostic kit for childhood sepsis, including a reagent for detecting osteocalcin levels in subjects.

[0011] Furthermore, the test sample for the kit is a plasma sample.

[0012] Thirdly, this application provides a prognostic system for childhood sepsis, comprising:

[0013] The data acquisition module is used to collect osteocalcin levels in patients on day 1 of sepsis. The processing module is used to implement the following steps: using the osteocalcin level measured on the first day of sepsis as the independent variable and whether organ support is needed as the dependent variable, a logistic regression model is constructed and an ROC curve is plotted to obtain the optimal threshold. The assessment module compares the patient's osteocalcin level on day 1 of sepsis with a threshold obtained from the processing module. If the level is higher than the threshold, the output indicates a high risk requiring organ function support; if the level is lower than the threshold, the output indicates a low risk.

[0014] This invention found that, compared with healthy and mildly infected children, children with sepsis had decreased plasma osteocalcin levels; and within the sepsis group, children with higher osteocalcin levels had a greater risk of needing organ support, suggesting that myelocalcin may be an important prognostic marker.

[0015] Compared to previous studies, this invention clarifies the importance of plasma osteocalcin in the diagnosis and prognostic assessment of childhood sepsis, demonstrating that higher osteocalcin concentrations are more predictive. Early detection of osteocalcin levels can effectively identify children with sepsis and organ dysfunction, enabling timely and appropriate treatment and improving patient prognosis.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This application found that osteocalcin decreases on day 1 of sepsis, and the level of decrease is significantly correlated with clinical outcomes of sepsis, including the number of organ dysfunctions, length of hospital stay, and need for organ support. This reveals that changes in plasma osteocalcin concentration are closely related to the clinical prognosis of sepsis patients, and early detection of osteocalcin levels can predict the degree of organ dysfunction and the risk of needing organ support, providing guidance for personalized treatment.

[0017] Osteocalcin is a specific biomarker for bone formation, primarily used to assess bone metabolic status. Its role in the disease context of sepsis has not been extensively studied. This application found that osteocalcin correlates with multiple immune-inflammatory markers and is also associated with clinical laboratory results and organ dysfunction scores in children with sepsis. As an important biomarker for organ dysfunction-related outcomes in children with sepsis, osteocalcin fills a research gap in its role in sepsis, supplements sepsis-related biomarkers, and provides a basis for adjusting treatment regimens. Plasma osteocalcin detection is a non-invasive method, safer and more convenient than traditional clinical testing methods, and suitable for widespread application in childhood sepsis.

[0018] Therefore, this invention provides a new biomarker for the diagnosis and prognostic assessment of childhood sepsis, enabling early identification of high-risk patients and providing more precise prevention and treatment decisions for clinicians, significantly improving the treatment efficacy and survival rate of childhood sepsis. Attached Figure Description

[0019] Figure 1 Example Results: (A) Osteocalcin levels were significantly lower in children with sepsis on the first day of hospitalization; (B) Spearman correlation analysis of osteocalcin on day 1 of sepsis with immune inflammatory markers and clinical data; (C) Children in the group requiring organ support during the course of sepsis had higher osteocalcin levels; (D) ROC curve.

[0020] A p-value < 0.05 is considered statistically significant; see attached figure. This indicates that p < 0.05. This indicates that p < 0.01. This indicates that p < 0.001. Detailed Implementation

[0021] To make the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings and tables.

[0022] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; the materials and reagents used are commercially available products unless otherwise specified; and all quantitative experiments involved are repeated three times, with the results being the average value.

[0023] In the following embodiments, some of the experimental materials and methods include: 1. Luminex detection Quantitative analysis of plasma immune inflammatory markers was performed using a Luminex Performance Assay 37-plex fixed panel (LX-171AL001M, R&D Systems) for human XL cytokines, in conjunction with a magnetic bead format on a Luminex 200 platform, following the manufacturer's instructions (Labex, Shanghai). Cytokine concentrations are expressed in pg / mL, and values ​​below the limit of detection were excluded from the analysis.

[0024] 2. Statistical Analysis Methods Continuous variables were expressed as mean ± standard deviation (SD) or median and interquartile range (IQR), while categorical variables were expressed as frequency (percentage). One-way ANOVA, Mann-Whitney U test, chi-square test, and Wilcoxon rank-sum test were used for intergroup comparisons. Spearman correlation analysis was used to assess the association between osteocalcin and immune inflammatory markers, clinical laboratory data of sepsis patients, demographic data, ICU-related scores, and pediatric prognosis. A logistic regression model with osteocalcin as the independent variable was established, and receiver operating characteristic (ROC) analysis was performed. Discriminant performance was assessed by area under the curve (AUC), and the optimal diagnostic cutoff was determined based on the Youden index.

[0025] All statistical analyses and plots were performed using R software (version 4.2.2). A p-value < 0.05 was considered statistically significant.

[0026] Experimental Example 1: Analysis of osteocalcin levels in healthy children, children with mild infections, and children with sepsis. In this embodiment, the osteocalcin levels of healthy children, children with mild infections, and children with sepsis were measured using Luminex assay technology (Table 1). Compared with healthy and children with mild infections, the plasma osteocalcin levels of children with sepsis were decreased (see Table 1). Figure 1 A). The results suggest that osteocalcin may play a key role in the early stages of sepsis in children, demonstrating its potential as a diagnostic biomarker for sepsis.

[0027] Table 1. Baseline characteristics and osteocalcin test results between groups

[0028] Experimental Example 2: Osteocalcin levels are correlated with some immune inflammatory markers and clinical data. In this embodiment, the levels of 35 immune inflammatory markers in healthy children, children with mild infections, and children with sepsis were measured using Luminex assay (baseline data are the same as in Table 1). Spearman correlation analysis was performed to explore the correlation between osteocalcin levels and immune inflammatory marker levels, as well as clinical data. The results indicated that osteocalcin levels were strongly correlated with the levels of tumor necrosis factor ligand superfamily member 12 (TWEAK / TNFSF12), and also showed some correlation with the levels of other immune inflammatory markers such as interleukin-11 (IL-11), interleukin-20 (IL-20), interleukin-34 (IL-34), interleukin-35 (IL-35), interleukin-27 (IL-27 / p28), matrix metalloproteinase-3 (MMP-3), tumor necrosis factor ligand superfamily member 14 (LIGHT / TNFSF14), soluble interleukin-6 receptor β chain (gp130 / sIL-6Rbeta), and pentraxin-3. Among clinical laboratory indicators, osteocalcin levels also correlated with classic sepsis markers such as PCT, IL-6, and CRP. Among the organ dysfunction scores commonly used in the ICU, P-MODS and PELOD2 scores also show a correlation with osteocalcin levels. Regarding clinical outcomes, osteocalcin levels are negatively correlated with the number of organ dysfunctions and length of hospital stay. Figure 1 B). The results suggest that osteocalcin is associated with multiple biomarkers in the inflammatory environment of sepsis and clinical outcomes, and may play an important role in the complex immunopathology of sepsis, demonstrating its ability as a diagnostic and prognostic biomarker for sepsis.

[0029] Experimental Example 3: Osteocalcin levels are associated with the risk of sepsis patients requiring organ support. To further evaluate the correlation between osteocalcin levels and the risk of organ support requirement in children with sepsis, this embodiment constructed a logistic regression model using the children's osteocalcin levels on day 1 as the independent variable and the need for organ support as the dependent variable, and plotted receiver operating characteristic (ROC) curves. Baseline information and test results for both groups are shown in Table 2. Logistic regression showed that log-transformed osteocalcin levels were an independent risk factor for organ support requirement in children with sepsis; higher osteocalcin levels were associated with a greater risk of organ support (OR=3.24, 95% CI: 1.23–12.13, P=0.041). This indicates that for every natural logarithmic increase in osteocalcin, the risk of organ support requirement increases 3.24-fold. Further ROC curve analysis was conducted to assess the predictive value of log-transformed osteocalcin for organ support needs. The area under the curve (AUC) was 0.726 (95% CI: 0.551–0.900), indicating that the model has good discriminative power. Figure 1(C, D) According to the Youden index, the optimal predictive probability threshold is 0.337, corresponding to an optimal osteocalcin threshold of 269.29 pg / mL, with a sensitivity of 93.8%, specificity of 50.0%, and accuracy of 70.6%. The corresponding clinical interpretation is: when a child's serum osteocalcin level is higher than 269.29 pg / mL, the model predicts a probability exceeding 33.7% that they will require organ support, and they should be considered a high-risk child.

[0030] Table 2. Analysis of differences between groups

[0031] Based on the above, this application provides a plasma osteocalcin as a prognostic biomarker for predicting whether children with sepsis will require organ support, providing a scientific basis for clinicians to develop personalized treatment plans, including the following steps: S1, collect osteocalcin levels on day 1 of sepsis in patients; S2, using the osteocalcin level measured on the first day of sepsis as the independent variable and whether organ support is needed as the dependent variable, construct a logistic regression model and plot the ROC curve to obtain the optimal threshold; S3 compares the patient's osteocalcin level on day 1 of sepsis with the threshold obtained in step S2. Patients with levels above the threshold are at higher risk of requiring organ function support.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make several improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention.

Claims

1. Application of osteocalcin in the preparation of diagnostic and / or prognostic products for childhood sepsis.

2. The application according to claim 1, characterized in that, The application of osteocalcin in the preparation of prognostic products for pediatric sepsis refers to measuring osteocalcin levels on the first day of hospitalization for sepsis patients to assess the degree of organ dysfunction and whether organ support is required.

3. The application according to claim 1, characterized in that, The product in question is a reagent kit.

4. A prognostic kit for childhood sepsis, characterized in that, This includes reagents for detecting osteocalcin levels in test subjects.

5. The reagent kit according to claim 4, characterized in that, The test sample for this kit is a plasma sample.

6. A prognostic system for childhood sepsis, characterized in that, include: The data acquisition module is used to collect osteocalcin levels in patients on day 1 of sepsis. The processing module is used to implement the following steps: using the osteocalcin level measured on the first day of sepsis as the independent variable and whether organ support is needed as the dependent variable, a logistic regression model is constructed and an ROC curve is plotted to obtain the optimal threshold. The assessment module compares the patient's osteocalcin level on day 1 of sepsis with a threshold obtained from the processing module. If the level is higher than the threshold, the output indicates a high risk requiring organ function support; if the level is lower than the threshold, the output indicates a low risk.

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