The role of serum tryptase in COVID-19 pathogenesis and its value as a prognostic marker: a single-center prospective cohort study

Differences of inflammatory and non-inflammatory indicators in Coronavirus disease-19 (COVID-19) with different severity

Background:Patients critically ill with coronavirus disease-2019 (COVID-19) feature hyperinflammation, and the associated biomarkers may be beneficial for risk stratification. We aimed to investigate the association between several biomarkers, including serum C-reactive protein (CRP), procalcitonin (PCT), D-dimer, and serum ferritin, and COVID-19 severity.Methods:We performed a comprehensive systematic literature search through electronic databases. The outcome of interest for this study was the composite poor outcome, which comprises mortality, acute respiratory distress syndrome, need for care in an intensive care unit, and severe COVID-19.Results:A total of 5350 patients were pooled from 25 studies. Elevated CRP was associated with an increased composite poor outcome [risk ratio (RR) 1.84 (1.45, 2.33), p < 0.001; I2: 96%] and its severe COVID-19 (RR 1.41; I2: 93%) subgroup. A CRP ⩾10 mg/L has a 51% sensitivity, 88% specificity, likelihood ratio (LR) + of 4.1, LR- of 0.5, and an area under curve (AUC) of 0.84. An elevated PCT was associated with an increased composite poor outcome [RR 3.92 (2.42, 6.35), p < 0.001; I2: 85%] and its mortality (RR 6.26; I2: 96%) and severe COVID-19 (RR 3.93; I2: 63%) subgroups. A PCT ⩾0.5 ng/ml has an 88% sensitivity, 68% specificity, LR+ of 2.7, LR- of 0.2, and an AUC of 0.88. An elevated D-dimer was associated with an increased composite poor outcome [RR 2.93 (2.14, 4.01), p < 0.001; I2: 77%], including its mortality (RR 4.15; I2: 83%) and severe COVID-19 (RR 2.42; I2: 58%) subgroups. A D-dimer >0.5 mg/L has a 58% sensitivity, 69% specificity, LR+ of 1.8, LR- of 0.6, and an AUC of 0.69. Patients with a composite poor outcome had a higher serum ferritin with a standardized mean difference of 0.90 (0.64, 1.15), p < 0.0001; I2: 76%.Conclusion:This meta-analysis showed that an elevated serum CRP, PCT, D-dimer, and ferritin were associated with a poor outcome in COVID-19. The reviews of this paper are available via the supplemental material section.

ObjectivesThe role of hematologic, inflammatory and biochemical parameters as biomarkers, their role in identifying risky patients in the early stage and their role in prognosis in COVID-19 Coronavirus disease 2019 (COVID-19) were investigated.MethodsThe study included patients who were hospitalized and followed up with a prediagnosis of COVID-19 in the first wave in our country at the University of Health Sciences, Sisli Hamidiye Etfal Training and Research Hospital Demographic and clinical characteristics as well as complete blood count, C reactive protein (CRP), procalcitonin (PCT), fibrinogen (FIB), ferritin, albumin (ALB), lactate dehydrogenase (LDH) levels on admission, third, seventh and 14th days were analyzed. Patients were grouped and compared according to the occurrence of death during hospital follow-up. Variables considered significant on mortality were analyzed with univariate and multivariate logistic regression models.ResultsThe study was conducted with 485 patients, 273 (56.3%) males and 212 (43.72%) females. The mean age of the patients was 58±16.2 years, and 71% were in the mild-moderate and 29% in the severe-critical disease group. Disease severity, the need for intensive care unit (ICU) follow-up, and the development of death were positively correlated with age, comorbidity, neutrophil (NE), leukocyte, neutrophil-lymphocyte ratio (NLR), PCT, CRP, ferritin, LDH values, and negatively correlated with lymphocyte (LE), ALB and hemoglobin (HGB) values. In multivariate analysis, elevated PCT at hospital admission (OR: 6.96 [1.63;39.65]), LDH ≥ 352U/L (OR: 4.35 [1.23;16.61]), LE<0.810 × 109/L (OR: 3.0 [1.16;7.85]) and advanced age (OR: 1.08 [1.03;1.14]) were independently associated with in-hospital death. In hemogram and acute phase reactant monitoring, PCT, CRP and LDH were the most valuable markers for predicting death, respectively (third-day AUC: 0.90;0.83;0.83 and seventh-day AUC: 0.95;0.90;0.89, respectively).ConclusionIn our study, leukocytes, lymphocytes, NLR, CRP, PCT, ferritin, albumin and LDH at admission were valuable in predicting poor prognosis. In addition, it was determined that increases in PCT, LDH and CRP during follow-up could be used to predict in-hospital death and to identify patients requiring close follow-up.

Predicting Severe Outcomes in COVID-19

Objective To explore the predictive values of serum procalcitonin (PCT) and C reactive protein (CRP) levels on coronary artery lesion (CAL) in acute phase of Kawasaki disease. Methods A total of 217 children with Kawasaki disease who hospitalized in Children′s Hospital of Chongqing Medical University from November 1, 2015 to December 31, 2016 were selected as research subjects. All the subjects have received standard Kawasaki disease treatments and all cases were in accord with the inclusion and exclusion criteria in this study. The gender, age, serum PCT and CRP levels, and echocardiographic findings within 30 d after the onset of Kawasake disease of all subjects were collected by retrospective method. According to children with acute Kawasaki disease complicated with CAL or not, they were divided into CAL group (n=22) and non-CAL group (n=29). Mann-Whitney U test was used to analyzed the differences of serum PCT and CRP levels between two groups. Chi-square test was used to compare the positive rates of serum PCT and CRP between two groups. Binary logistic regression analysis model was used to construct a new combined predictor L by serum PCT and CRP levels for predicting CAL in children with Kawasaki disease. And receiver operating characteristics (ROC) curves for new combined predictor L, serum PCR and CRP levels were built respectively, to evaluate the predictive values of combined predictor L and serum PCT, CRP levels on CAL in children with Kawasaki disease. The area under ROC curve (ROC-AUC) for combined predictor L and serum PCT, CRP levels in predicting CAL in children with Kawasaki disease all were calculated. The optimal cut-off point of combined predictor L and serum PCT, CRP levels predicting CAL in children with Kawasaki disease was obtained where the Youden index reached the maximum value. And diagnostic parameters such as sensitivity and specificity were also calculated for comparison.There were no statistically significant differences between two groups in the aspects of gender ratio, age, and so on (P>0.05). Results ①The medians of serum PCT level in CAL group and non-CAL group were 1.16 μg/L and 0.04 μg/L, respectively. The medians of serum CRP level in CAL group and non-CAL group were 25.0 mg/L and 16.4 mg/L, respectively. The levels of serum PCT and CRP in CAL group both were statistically higher than those in non-CAL group, and both the differences were statistically significant (Z=-2.454, P=0.046; Z=-6.412, P<0.001). There were no statistically significant differences in the positive rates of serum PCT and CRP between two groups (χ2=1.222, P=0.269; χ2=0.665, P=0.415). ②Binary logistic regression analysis model with complicated with CAL or not as a dichotomous outcome variable, and levels of serum CRP and PCT as independent variables showed that elevated levels of serum CRP and PCT were independent risk factors for children with Kawasaki disease complicated with CAL (OR=1.077, 95%CI: 1.027-1.190, P<0.001; OR=1.046, 95%CI: 1.015-1.078, P=0.003). The expression of combined predictor L was L=x1+ 0.608x2, in which x1 and x2 referred to the levels of serum CRP and PCT, respectively. ③ROC curve analysis indicated the values of ROC-AUC for combined predictor L, levels of serum PCT and CRP in predicting children with Kawasaki disease complicated with CAL were 0.773 (95%CI: 0.700-0.845, P<0.001), 0.560 (95%CI: 0.475-0.645, P=0.148), and 0.767 (95%CI: 0.695-0.839, P<0.001), respectively. The optimal cutoff values of combined predictor L, levels of serum PCT and CRP were 23.068, 2.32 μg/L, and 22.0 mg/L, respectively, and the sensitivities were 68.1%, 30.6% and 68.1%, respectively, the specialties were 83.4%, 86.9% and 80.7%, respectively. Conclusions Monitoring levels of serum PCT, CRP and combined predictor L (L=x1+ 0.608x2, x1 and x2 referred to levels of serum CRP and PCT, respectively) have predictive values to evaluate the occurrence of children with Kawasaki disease complicating CAL in acute phase. Key words: Procalcitonin; C reactive protein; Mucocutaneous lymph node syndrome; Coronary artery lesion; Predictive value; Combined predictive indicator; Logistic regression model; Child

Coronavirus disease 2019 (COVID-19) had caused a worldwide pandemic with public health emergencies since 2020. For the symptomatic patients, high mortality rate was observed if without timely and optimized management. In this study, we aimed to investigate the predictive and prognostic roles of hematologic and biochemical parameters obtained in the emergency department (ED) for COVID-19 patients. We conducted a retrospective study in a dedicated COVID-19 medical center, recruiting a total of 228 COVID-19 patients with 86 severe and 142 non-severe cases. Both the hematologic and biochemical parameters obtained in the ED upon arrival were analyzed to evaluate the association of the biomarkers with disease severity and prognosis among COVID-19 patients. Among these parameters, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), procalcitonin (PCT), lactate dehydrogenase (LDH), ferritin, and D-dimer were significantly higher in the severe group than the non-severe one, whereas the platelet count and lymphocyte-to-monocyte ratio were significantly lower. Receiver operating characteristic curve analysis revealed that the areas under curve of CRP, PCT, LDH, ferritin, D-dimer, and NLR for differentiating the severity of COVID-19 were 0.713, 0.755, 0.763, 0.741, 0.733, and 0.683, respectively, whereas the areas under curve of CRP, PCT, LDH, ferritin, D-dimer, and NLR for differentiating the mortality of COVID-19 were 0.678, 0.744, 0.680, 0.676, 0.755, and 0.572, respectively. Logistic regression analysis revealed that CRP, PCT, LDH, ferritin, D-dimer, and NLR were independent indicators for prediction of severe COVID-19, and LDH and ferritin were independent factors associated with the mortality in COVID-19. In conclusion, higher CRP, PCT, LDH, ferritin, D-dimer, and NLR were associated with severe COVID-19, whereas higher LDH and ferritin were associated with the mortality in COVID-19. These findings could help early risk stratification in the ED and contribute to optimized patient management.

Rationale: Up to date, the exploration of clinical features in severe COVID-19 patients were mostly from the same center in Wuhan, China. The clinical data in other centers is limited. This study aims to explore the feasible parameters which could be used in clinical practice to predict the prognosis in hospitalized patients with severe coronavirus disease-19 (COVID-19).Methods: In this case-control study, patients with severe COVID-19 in this newly established isolation center on admission between 27 January 2020 to 19 March 2020 were divided to discharge group and death event group. Clinical information was collected and analyzed for the following objectives: 1. Comparisons of basic characteristics between two groups; 2. Risk factors for death on admission using logistic regression; 3. Dynamic changes of radiographic and laboratory parameters between two groups in the course.Results: 124 patients with severe COVID-19 on admission were included and divided into discharge group (n=35) and death event group (n=89). Sex, SpO2, breath rate, diastolic pressure, neutrophil, lymphocyte, C-reactive protein (CRP), procalcitonin (PCT), lactate dehydrogenase (LDH), and D-dimer were significantly correlated with death events identified using bivariate logistic regression. Further multivariate logistic regression demonstrated a significant model fitting with C-index of 0.845 (p<0.001), in which SpO2≤89%, lymphocyte≤0.64×109/L, CRP>77.35mg/L, PCT>0.20μg/L, and LDH>481U/L were the independent risk factors with the ORs of 2.959, 4.015, 2.852, 3.554, and 3.185, respectively (p<0.04). In the course, persistently lower lymphocyte with higher levels of CRP, PCT, IL-6, neutrophil, LDH, D-dimer, cardiac troponin I (cTnI), brain natriuretic peptide (BNP), and increased CD4+/CD8+ T-lymphocyte ratio and were observed in death events group, while these parameters stayed stable or improved in discharge group.Conclusions: On admission, the levels of SpO2, lymphocyte, CRP, PCT, and LDH could predict the prognosis of severe COVID-19 patients. Systematic inflammation with induced cardiac dysfunction was likely a primary reason for death events in severe COVID-19 except for acute respiratory distress syndrome.

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

BackgroundHospital-acquired infection (HAI) in patients with COVID-19 admitted to the intensive care unit (ICU) is associated with increased mortality. The ‘cytokine storm’ associated with COVID-19 leads to extreme elevation of inflammatory biomarkers, including C-reactive protein (CRP). Procalcitonin (PCT) has been shown to be more discriminative than CRP in distinguishing HAI from other inflammatory processes.ObjectivesTo investigate the utility of PCT in detecting HAI in patients with severe COVID-19.MethodsClinical and laboratory data from all patients admitted to a dedicated ICU with confirmed severe COVID-19 from 1 April 2020 to 31 August 2020 were prospectively captured. HAI was confirmed by serial PCT and CRP measurements, as well as microbiological data (positive microbiological cultures in clinical context). Data from patients who were on antibiotics on ICU admission, had a positive culture for a presumed pathogen during the first 48 hours of ICU admission, or already had suspected or proven HAI on admission were excluded. Optimal cut-offs with the highest sensitivity and specificity were determined. The discriminative power of PCT was assessed for each outcome, using receiver operating characteristic (ROC) analysis describing the area under the curve. Similarly, negative predictive values (NPVs) and positive predictive values (PPVs) were determined. The sensitivity and specificity for different PCT cut-off levels were calculated.ResultsOf 92 patients, 35 had confirmed HAI, which was significantly associated with mechanical ventilation (p<0.001) and mortality (p<0.001). ROC analysis demonstrated that a threshold PCT level of 0.22 μg/L resulted in 97% sensitivity and 40% specificity for predicting HAI. Similarly, sensitivity and specificity for CRP were 91.4% and 38.6%, respectively, when the CRP level was 133 mg/L. In patients with a PCT level <0.25 μg/L, the NPV was 92%, whereas for PCT levels >1.00 μg/L, the PPV was >50%. For PCT levels >40 μg/L, the PPV was 100%.ConclusionDuring HAI, PCT levels >1.00 μg/L had a moderate PPV of 52%, whereas levels <0.26 μg/L ruled out HAI with an NPV of 92%. With increased PCT values, the PPV rose to 100%, making it a better biomarker than CRP.Study synopsisWhat the study adds. During an episode of hospital-acquired infection (HAI) in patients with severe COVID-19, procalcitonin (PCT) levels >1.00 μg/L had a moderate positive predictive value (PPV) of 52%, whereas levels <0.26 μg/L had a negative predictive value (NPV) of 92% for proven HAI. For PCT levels >40 μg/L, the PPV was 100%.Implications of the findings. At levels <0.26 μg/L, PCT had an NPV >90%. This ‘rule-out’ characteristic of PCT may be especially valuable in scenarios of diagnostic equipoise with regard to the presence of bacterial co-infection. Clinicians should take care to not unjustifiably associate elevations in PCT levels with the presence of bacterial co-infection, unless levels are extremely high, in which case the PPV rises significantly

Interferon lambda 3 in the early phase of coronavirus disease-19 can predict oxygen requirement.

Biomarkers such as Interleukin-6 (IL-6), Procalcitonin (PCT), C-reactive protein (CRP) and Neutrophil-Lymphocyte Ratio (NLR) have a role in the pathogenesis of severe coronavirus disease 2019 (COVID-19). The aim of this study was to explore the differences between serum levels of such biomarkers in severe and non-severe COVID-19 cases and compare them with normal people and to evaluate the sociodemographic variables and chronic diseases effect on the severity of COVID-19. The study included 160 subjects, divided into two groups, a case group of 80 patients, and a control group of 80 normal persons. The case group was divided into two subgroups: 40 severe COVID-19 patients and 40 patients with non-severe disease. Blood IL-6 was assessed by an enzyme-linked immunosorbent assay (ELISA), PCT by an immunoassay, CRP by an immunoturbidimetric assay and NLR from CBC. The levels of IL-6, PCT, CRP, and NLR were significantly higher in the case group than in control group (p= 0.001, for all). However, there was no difference between these biomarkers level in the non-severe COVID-19 subgroup and the control group (p&gt;0.05 for all). The proportion of severe COVID-19 was significantly higher in patients aged &gt;50 years, and in patients with chronic diseases (p=0.046 and p=0.001, respectively). We also found a strong correlation between such biomarkers and old age, and chronic diseases with the disease severity. There was a significant difference in the level of the three biomarkers (IL-6, PCT, CRP, and NLR) between patients’ subgroups and the control group. In conclusion, since the levels of these biomarkers are correlated with the severity of the COVID-19 disease, and there was a difference in the levels between the groups with severe and non-severe symptoms, we suggest a role of these biomarkers in predicting the severity COVID-19 disease and its poor prognosis.

Background and objectivesInfections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are rapidly spreading, posing a serious threat to the health of people worldwide, resulting in the World Health Organization officially declaring it a pandemic. There are several biochemical markers linked with predicting the severity of coronavirus disease. This study aims to identify the most effective predictive biomarker such as C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), procalcitonin (PCT), and D-dimer, among others, in predicting the clinical outcome of the disease.Materials and methodsThis study was conducted as a retrospective, observational, multi-centric study, including all admitted COVID-19 positive patients only. The disease outcome was followed along with the hospital course of every patient at the time of analysis. Baseline laboratory investigations of all patients were monitored both at admission and discharge. A comparative analysis was done between the survivors (n=263) and non-survivors (n=101). Statistical analysis was conducted using IBM SPSS Statistics for Windows Version 25 (Armonk, NY: IBM Corp.).ResultsOf 364 patients, 65.7% were in the isolation ward, and 34.3% were in the intensive care unit; 72.3% of patients survived, while 27.7% of patients died. The mean age of the study population was 52.6 ± 15.8 years with female patients significantly younger than male patients (p=0.001) and 50 to 75 years being the most common age group (p=0.121). Among the survivors versus non-survivors of COVID-19, there were significant differences in total leukocyte count (p<0.001), neutrophil count, (p<0.001), lymphocyte count (p<0.001), urea (p<0.001), serum bicarbonate (p=0.001), CRP levels (p<0.001), LDH (p=0.013), and D-dimer (p<0.001) at admission. At discharge, the laboratory values of non-surviving patients showed significant leukocytosis (p<0.001), neutrophilia (p<0.001), lymphocytopenia (p<0.001), decreased monocytes (p<0.001), elevated urea and creatinine (p<0.001), hypernatremia (p<0.001), decreased serum bicarbonate levels (p<0.001), elevated CRP level (p=0.040), LDH (p<0.001), ferritin (p=0.001), and D-dimer (p<0.001).Among the recovered patients, the laboratory investigations at admission were significantly different from those at discharge like increased platelets (p=0.007), lower neutrophil count (p=0.001), higher lymphocyte count (p=0.005), an improved creatinine (p=0.020), higher sodium (p=0.008), increased bicarbonate levels (p<0.001), decreased CRP levels (p<0.001), and a lower LDH (p=0.039). However, the laboratory values of non-surviving patients had shown a lower hemoglobin (p=0.016), increased mean cell volume (p<0.001), significantly increased total leukocyte count (p<0.001), increased urea and creatinine (p<0.001), hypernatremia (p<0.001), increased bicarbonate (p=0.025), elevated D-dimer levels (p=0.043), and elevated PCT (p=0.021) on discharge. Receiver operating characteristic analysis concluded LDH (area under the curve [AUC]: 0.875), D-dimer (AUC: 0.803), and PCT (AUC: 0.769) were superior biomarkers to ferritin (AUC: 0.714) and CRP (AUC: 0.711) in predicting the fatality of COVID-19.ConclusionInflammatory markers are a useful guide for predicting mortality, and the study results concluded that LDH, PCT, D-dimer, CRP, and ferritin were effective biomarkers.

Outcome prediction by serum calprotectin in patients with COVID-19 in the emergency department

To explore the value of different inflammatory markers in predicting the severity of coronavirus disease 2019 (COVID-19) in patients with type 2 diabetes mellitus (T2DM). A total of 116 patients with COVID-19 in patients with T2DM were collected from December 2022 to March 2023 and were divided into a mild case group (77 cases) and a severe case group (39 cases). The ratio of neutrophil to lymphocyte (NLR), platelet-to-lymphocyte ratio (PLR), neutrophil to lymphocyte × platelet ratio (NLPR), lymphocyte ratio to monocyte (LMR), systemic inflammatory response index (SIRI), systemic inflammatory index (SII), systemic inflammatory composite index (AISI), procalcitonin (PCT), C-reactive protein (CRP) and lactate dehydrogenase (LDH) were compared between the two groups. The screening effect of each variable on the progression of the disease was analyzed using receiver operating characteristic (ROC) curves. NLR, PLR, NLPR, MLR, SIRI, SII, AISI, LDH, CRP and PCT in severe case group were higher than those in mild case group (P<0.05), and LMR was lower than those in mild case group (P<0.05). ROC curve analysis further demonstrated the diagnostic performance of these biomarkers, with PCT having the largest area under the ROC curve (AUCROC) of 0.83. NLR, PLR, NLPR, SIRI, SII, LDH, CRP and PCT demonstrate greater reliability in diagnostic value and clinical utility for predicting the severity of COVID-19 in patients with T2DM.

Objective: To evaluate the dynamic changes in neutrophil-to-lymphocyte ratio (NLR), interleukin-6 (IL-6), C-reactive protein (CRP), and procalcitonin (PCT) levels in children with Mycoplasma pneumoniae pneumonia (MPP) complicated by myocardial injury and to determine their predictive value both individually and in combination. Methods: 150 children diagnosed with MPP at Jiujiang Maternal and Child Health Hospital between June 2023 and June 2024 were selected. Patients were divided into the myocardial damage group (MD group, n = 65) and the non-myocardial damage group (non-MD group, n = 85), based on the presence of myocardial injury. Ninety hospitalized children without MPP served as the control group (Con group). Myocardial enzyme profile indicators, including lactate dehydrogenase (LDH), α-hydroxybutyrate dehydrogenase (α-HBDH), aspartate aminotransferase (AST), high-sensitivity cardiac troponin I (hs-cTnI), creatine kinase (CK), and creatine kinase-MB (CK-MB), were measured using a chemiluminescent immunoassay analyzer. Serum NLR, IL-6, CRP, and PCT levels were determined using appropriate analyzers. The correlation between these markers and myocardial enzyme indicators was analyzed using Spearman correlation analysis. Multivariate logistic regression was applied to identify risk factors for myocardial injury in MPP patients. Results: Serum levels of NLR, IL-6, CRP, and PCT in the MD and non-MD groups were significantly higher than in the Con group (P &lt; 0.05), with the MD group showing higher levels than the non-MD group (P &lt; 0.05). These markers were positively correlated with myocardial enzyme indicators. Logistic regression identified elevated NLR, IL-6, CRP, PCT, LDH, α-HBDH, AST, hs-cTnI, CK, and CK-MB as risk factors for myocardial injury in MPP patients (P &lt; 0.05). Conclusion: Elevated levels of NLR, IL-6, CRP, PCT, and myocardial enzymes are significant risk factors for myocardial injury in children with MPP, offering valuable insights for prevention and prognosis.