Objective To establish the pediatric reference intervals for Troponin Ⅰ and Creatine kinase-MB (CK-MB).Methods Healthy children (223 boys and 162 girls) aged from 7 months to 12 years old were studied.Blood specimens were collected and centrifuged,all serum samples were kept refrigerated below-70 ℃.Troponin Ⅰ and CK-MB were measured on the UniCel DxI 800 immunoassay system (Beckman Coulter) on the same day.Nonparametric statistics was used to estimate the 99th percentile reference intervals.Results The children were divided into three groups (group A 128 cases; group B 128 cases;group C 129 cases) according to age.The upper reference limits for CK-MB were dependent of age,and the group A (7 months-1 years) was shown to be 13.41 μg/L,the group B (2-3 years) was shown to be 9.35 μg/L,the group C (4-12 years) was shown to be 5.48 μg/L.The upper reference limit for Troponin Ⅰ was independent of age or gender and shown to be 0.01 μg/L among 385 children.Conclusions Pediatric reference intervals for Troponin Ⅰ and CK-MB have been defined in healthy children at a relevant age group (7 months-12 years).It is effective for clinical diagnosis and treatment of myocardial damage for children by determining reference intervals for Troponin Ⅰ and CK-MB.

Objective To investigate the clinical manifestation,therapeutic methods and treatmenteffectiveness of hand contracture due to extravasation injury from peripheral intravenous therapy in children.Methods Data of 6 children who had received treatment for hand contracture in our hospital from March 2004 to September 2011 were retrospectively analyzed.There were 3 boys and 3 girls,aged from 24 to 51 months (average,38 months).Two children underwent extensor tenolysis and dorsal capsular release at the metacarpophalangeal (MCP) joints.The other 4 children received conservative treatment,including physical therapy (ultrasound and medium frequency pulse) to reduce the hand swelling and peritendinous adhesion,active and passive functional exercise of digital joints and night splint protection.Results The MCP joint could be passively flexed to 90° intraoperatively in 2 children who underwent operation; however the contracture recurred at 2 months and 6 months after operation,respectively,and then the MCP joints were fixed at 0° position.For 4 children who received conservative treatment,although the active flexion of their MCP joints ranged from 30° to 45° during the rehabilitative procedure,recurrence of hand contracture was observed after the cessation of the rehabilitation in all children,and the range of active MCP joints flexion varied from 0° to 15°.Conclusion The mechanism underlying hand contracture due to extravasation injury from peripheral intravenous therapy remains elusive.Either simple conservative or surgical management results in poor functional outcomes.Combined therapy based on different indications for conservative and surgical management may improve the outcomes.

Objective:To explore the performance of the commonly used whole blood C-reactive protein (CRP) detection systems and give related recommendation on the performance requirements of detection systems.Methods:A total of 7 540 venous blood samples from 26 maternal, child and children′s hospitals were collected to conduct this multi-center study on the analytical performance of 5 commonly used whole blood CRP detection systems from March to April in 2019. The blank check, carryover, repeatability, intermediate precision, linearity, sample stability, influence of hematocrit/triglyceride/bilirubin, comparison with SIEMENS specific protein analyzer and trueness were evaluated. The 5 systems included BC-5390CRP autohematology analyzer, AstepPLUS specific protein analyzer, Ottoman-1000 Automated Specific Protein POCT Workstation, i-CHROMA Immunofluorometer equipment Reader and Orion QuikRead go detecting instrument. The 5 systems were labeled as a, b, c, d and e randomly.Results:Within the 5 systems, all values of blank check were less than 1.00 mg/L, the carryovers were lower than 1.00%. The repeatability of different ranges of CRP concentrations including 3.00-10.00, 10.00-30.00 and>30.00 mg/L were less than 10.00%, 6.00% and 5.00%, respectively, and the intermediate precision was less than 10.00%. The linearity correlation coefficients of the 5 systems were all above 0.975, while the slope was within 0.950-1.050. Whole blood samples were stable within 72 hours both at room temperature (18-25 ℃) and refrigerated temperature (2-8 ℃). The CRP results were rarely influenced by high triglyceride or bilirubin, except for the immmunoturbidimetric test based on microparticles coated with anti-human CRP F(ab) 2 fragments. When triglyceride was less than 15.46 mmol/L, the deviation of CRP was less than 10.00%. When bilirubin was less than 345.47 μmol/L, the deviation of CRP was less than 10.00%. CRP was more susceptible to Hct on the systems without Hct correction. The deviation of CRP between different Hct dilution concentration and 40% dilution concentration can reach as high as 67.48%. The correlation coefficients ( r) of 5 systems were all more than 0.975 in the range of 0-300.00 mg/L compared with Siemens specific protein analyzer. All systems passed the trueness verification using the samples with specified values of 12.89 and 30.60 mg/L. Conclusion:The performance of 5 systems can basically meet the clinical needs, but it is suggested that the whole blood CRP detection system without automatic Hct correction should be modified manually.