Infection-related point-of-care testing / 中国小儿急救医学

Rapid diagnosis is an important link in the prevention and control of infectious diseases.Point-of-care testing(POCT)is portable, fast, easy to operate, intelligent and sensitive, which has been widely used in the detection of pathogenic microorganisms of infectious diseases, host biomarkers, microbial drug sensitivity in recent years.It is of great significance for the monitoring and management of disease epidemiology and rational use of antibiotics.This review summarized the application of POCT in the diagnosis and treatment of pediatric infectious diseases.

Evaluation of the performance of systems for whole blood C-reactive protein detection: a multi-center study / 中华检验医学杂志

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.

Analysis of Distribution and Drug Resistance of Bloodstream Infection Pathogens in A Children ’s Hospital from Zhengzhou during 2014-2019 / 中国药房

OBJECTIVE：To analyze the distribution and drug resistance of bloodstream infection pathogens in a Children’s Hospital from Zhengzhou，and to provide reference rational selection of drugs in anti-infective treatment. METHODS：By retrospective analysis，128 318 blood culture specimens were collected from inpatients in the Affiliated Children’s Hospital of Zhengzhou University from Oct. 2014 to Sept. 2019. The positive rate，clinical symptoms and clinical diagnosis of children with bloodstream infection were analyzed statistically. WHONET 5.6 software was used to analyze pathogenic bacteria of positive specimen，the departments and the resistance of pathogens to the main clinical antibiotics. RESULTS：In 128 318 blood culture samples of inpatients，the positive rate was 2.14％ （2 746/128 318）；among 2 746 blood culture positive sample，the main Symptom of childrem with blood stream infection was fever（1 986/2 746）；main clinical diagnosis included sepsis（1 679/2 746）， bronchopneumonia（858/2 746），purulent meningitis（555/2 746）. The main departments included neonatal diagnosis and treatment center （1 090 strains，accounting for 39.69％） [neonatal intensive care unit （279 strains，accounting for 10.16％），neonatal surgery department （223 strains，accounting for 8.12％），neonatal internal medicine department （209 strains，accounting for 7.61％），infant pediatrics department（200 strains，accounting for 7.28％） and premature pediatrics department（179 strains， accounting for 6.52％）]，hematology oncology department （216 strains，accounting for 7.87％），cardio vascular medicine department（206 strains，accounting for 7.50％）. Gram-positive bacteria accounted for 72.80％，Gram-negative bacteria 24.21％， fugus 2.99％. Among Gram-positive bacteria，coagulase negative staphylococcus（1 414 strains）and Staphylococcus aureus（146 strains）were the most common. The resistance rate of the former to penicillin G，oxacillin and erythromycin was more than 80％， and that of the latter to penicillin G and erythromycin was more than 80％. Among Gram-negative bacteria，Klebsiella pneumoniae （183 strains） and Escherichia coli （172 strains） were the most common. The resistance rates of the former to ampicillin， piperacillin，ampicillin/sulbactam and cefazolin were more than 80％，and the latter to ampicillin and tetracycline were more than 80％. Among the fungus，Candida albicans（42 strains）and Candida parapsilosis（22 strains）were the most common，and the resistance rate to common antifungal drugs was less than 10％. CONCLUSIONS：The pathogens of bloodstream infection in the hospital are complex，mainly coagulase negative staphylococcus and K. pneumoniae，and the drug resistance is severe.

Epidemiology and clinical analysis of 24 children with brucellosis / 中华地方病学杂志

Objective:To analyze the epidemiological and clinical characteristics of children with brucellosis, and to provide a practical basis and experience for clinical diagnosis and treatment of brucellosis.Methods:Retrospective analysis was used to collect clinical data of children with brucellosis diagnosed at the Children's Hospital Affiliated to Zhengzhou University from May 2015 to October 2017, and their epidemiological characteristics, clinical manifestations, laboratory tests, and clinical diagnosis and treatment were summarized.Results:A total of 24 children were included, including 14 males and 10 females, with an average age of 6 years (1 year 2 months to 12 years old). Except February, onset throughout the year, higher incidence was from May to July (14 cases, 58.33%). The exposure history of the children was mainly exposure to cattle and sheep and consumption of beef and mutton (18 cases, 75.00%). The main clinical manifestations were fever in 24 cases (100.00%), bone and joint pain in 14 cases (58.33%), hepatomegaly in 9 cases (37.50%), splenomegaly in 7 cases (29.17%). Tube agglutination test (SAT) was positive in 21 cases (87.50%), weakly positive in 1 case (4.17%) and negative in 2 cases (8.33%). Brucella was detected in all 24 cases by microbial culture, and in 18 cases (75.00%) by blood culture. Eighteen cases (75.00%) had liver dysfunction. Thirteen cases were misdiagnosed, and the misdiagnosis rate was as high as 54.17%. Twenty-two cases had been cured after treatment, 2 cases relapsed and recovered after continued treatment. Conclusions:Children with brucellosis have diverse epidemiology and clinical features, and are easily misdiagnosed. For children with fever, bone and joint pain and exposure history, pediatricians should be alert to the possibility of brucellosis, conduct microbiological and serological tests, in order to timely, accurate and standardized diagnosis and treatment of children with brucellosis.

Application of CLSI EP12-A2 and EP15-A2 documents in the performance evaluation of Adenovirus IgM CLIA microparticles / 中华实验和临床病毒学杂志

Objective@#Application of Clinical and Laboratory Standards Institute evaluation protocols-12 approved guideline 2nd edition (CLSI EP12-A2) and EP15-A2 documents in the performance evaluation of Adenovirus IgM CLIA microparticles.@*Methods@#Referring to the EP15-A2 method , three samples of high and low concentration were selected. Each sample test was repeated 4 times one day for 5 days, and the total imprecision was calculated. Referring to the EP12-A2 method , samples of C50, C50-20% and C50+ 20% were prepared and repeated 40 times, to verify C50±20% bounds the C5~C95 interval. Compared with diagnostic accuracy criteria, the sensitivity and specificity were calculated. Compared with ELISA method , the concordance rate and Kappa value were calculated.@*Results@#The total imprecision CV (%) was less than 8%, lower than that announced by manufacturer. C50±20% concentration fall outside the C5~C95 interval. Compared with diagnostic accuracy criteria, the sensitivity was 100% (95%CI: 79.6%~100%), specificity was 97.8% (95%CI: 94.5%~99.1%), Kappa value was 0.871. Compared with ELISA method , the positive concordance rate was 66.7%(95%CI: 53.6%~77.7%), negative concordance rate was 97.4%(95%CI: 95.4%~98.5%)total concordance rate was 93.9%(95%CI: 91.6%~95.6%), Kappa value was 0.678.@*Conclusions@#The performance of Adenovirus IgM CLIA microparticles can meet clinical requirements.

Effect of CHL1 gene on cell viability, invasiveness and apoptosis in neuroblastoma cells / 中华肿瘤杂志

Objective@#To investigate the effect and mechanisms of CHL1 gene overexpression on cell viability, invasiveness and apoptosis in neuroblastoma cells.@*Methods@#The empty plasmid (pcDNA3.1 group) and CHL1 recombinant plasmid (pcDNA3.1-CHL1 group) were transfected into SK-N-SH human neuroblastoma cells, and the untransfected cells were used as blank control. Forty-eight hours after transfection, the protein expressions of CHL1, PCNA, MMP-2, Bax, STAT3 and p-STAT3 were detected by western blot. Meanwhile, cell viability, invasion and apoptosis were detected by MTT, transwell and flow cytometry assays, respectively.@*Results@#The expression level of CHL1 protein in pcDNA3.1-CHL1 group was 0.612±0.052, which was higher than that of pcDNA3.1 group 0.122±0.014 and blank control group 0.120±0.013, with statistically significant difference (P<0.05). After 24, 48 and 72 hours of transfection, the absorbance (A) values of SK-N-SH cells in the pcDNA3.1-CHL1 group were 0.328±0.035, 0.502±0.051 and 0.688±0.064, respectively, whereas those in the pcDNA3.1 group were 0.562±0.050, 0.796±0.065 and 0.973±0.077, respectively. The differences were statistically significant (P<0.05). The invaded cells in the pcDNA3.1-CHL1 group were 104.9±3.7, which were lower than that in the pcDNA3.1 group (175.6±4.6), with statistically significant difference (P<0.05). Additionally, the apoptotic rate of pcDNA3.1-CHL1 cells was (23.46±1.22)%, which was higher than that in pcDNA3.1 group (3.45±0.20)%(P<0.05). Furthermore, the levels of PCNA, MMP-2, Bax and p-STAT3 proteins in pcDNA3.1-CHL1 group were 0.156±0.018, 0.122±0.015, 0.285±0.032 and 0.023±0.004, respectively, whereas those in pcDNA3.1 group were 0.542±0.053, 0.196±0.021, 0.073±0.009 and 0.057±0.007, respectively. There were statistically significant differences between two groups (P<0.05).@*Conclusion@#Overexpression of CHL1 inhibits the cell viability and invasion, as well as induces apoptosis of neuroblastoma cells, which is related to the inhibition of STAT3 signaling pathway.

Evaluation of intravoxel incoherent motion-diffusion weighted imaging in predicting early recurrence of hepatocellular carcinoma after curative hepatectomy / 中华肝胆外科杂志

Objective To investigate the value of preoperative intravoxel incoherent motiondiffusion weighted imaging (IVIM-DWI) in predicting early recurrence of hepatocellular carcinoma (HCC)after curative hepatectomy.Methods The clinical data of 51 HCC patients who underwent curative hepatectomy at Beijing Tsinghua Changgung Hospital,Tsinghua University from December 2014 to March 2017 were retrospectively analyzed.The study included 45 males and 6 females,aged 56.4 ± 10.1.The patients were divided into the early-recurrence group (21 patients) and the non-recurrence group (30 patients) according to whether there was HCC recurrence within 1 year after curative hepatectomy.The parameters of the lesions were measured and calculated:the apparent diffusion coefficient (ADC) value,true diffusion coefficient (D) value,perfusion-related diffusion coefficient (D *) value and perfusion fraction (f) value.Receiver operating characteristic curves (ROC) were used to evaluate the prediction efficiency of the parameters.Results The ADC and D values of the early-recurrence group were significantly lower than the non-recurrence group.The differences were statistically significant (P ＜ 0.05).In predicting early recurrence of HCC after curative hepatectomy,the ADC values showed the area under ROC was 0.713 (95％ CI:0.572 ～0.855),the sensitivity was 0.857 and specificity was 0.567 when the optimal threshold value was 1.24 × 10-3mm2/s.The D values in predicting early recurrence demonstrated the area under ROC was 0.740 (95％ CI:0.602 ～ 0.877),the sensitivity was 0.905 and specificity was 0.600 when the optimal threshold value was 1.03 × 10-3 mm2/s.Conclusions The ADC and D values of IVIMDWI could provide evidence in predicting early recurrence of HCC after curative hepatectomy.The D values had a higher prediction efficiency.

Preparation of peptide mimotope-based diagnostic antigen of Epstein-Barr virus infection / 中华实验和临床病毒学杂志

Objective@#To prepare peptide minotope-based recombinant diagnostic antigen of Epstein-Barr virus (EBV) infection and evaluate its antigenicity preliminarily.@*Methods@#With Trx at the N-terminal and His tag at the C-terminal, the peptide minotope of EBV (GP125, F1, A2, A3C2) was expressed in Escherichia coli and purified by affinity and anion exchange chromatography (designated 'H58’); based on antigenicity of H58 identified by Western blotting (WB), we constructed and evaluated a novel early diagnostic ELISA for EBV infection.@*Results@#The soluble H58 protein with high concentration (2.8 mg/ml) and purity (99.01) was obtained; WB analysis found that there was an obvious band (28 ×103) on the NC membrane, using H58 anti-Trx monoclonal antibody or acute-phase sera of EBV infection as the first antibody. With the novel ELISA, 50 positive sera of EBV infection and 50 negative sera were detected, displaying that the grouping of OD value of positive serum (95%CI: 1.233-1.489) and negative serum (95%CI: 0.113-0.159) was different (P<0.05) with the sensitivity 98.0%, specificity 96.0% and kappa value 0.940.@*Conclusions@#By E. coli expression and affinity and ion exchange chromatography purification, the peptide minotope-based recombinant diagnostic antigen of EBV infection was obtained with excellent antigenicity, which could be applied for serological detection of EBV infection.

A novel splicing mutation in COL1A1 gene caused type I osteogenesis imperfecta in a Chinese family / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study a family affected with osteogenesis imperfecta for potential mutations in COL1A1 gene.</p><p><b>METHODS</b>Clinical data of an affected family was collected. Potential mutation of the COL1A1 gene was screened using polymerase chain reaction and direct sequencing. Suspected mutation was detected in 20 unaffected relatives and 200 unrelated healthy controls.</p><p><b>RESULTS</b>Analysis of RNA splicing has revealed a c.3208G/A mutation, which created a new splice sites and led to a frameshift mutation. The same mutation was not detected in the unaffected relatives or the 200 healthy controls.</p><p><b>CONCLUSION</b>Mutations of the COL1A1 gene are one of the major causes of osteogenesis imperfecta in Chinese population. Our finding has enriched the mutation spectrum of type I collagen genes.</p>