OBJECTIVE To explore the effect of tracking methodology on investigation of contamination incidents of bronchoalveolar lavage fluid(BALF)specimens from the children.METHODS The onsite tracking was carried out for the contamination incidents of BALF specimens of the children through the tracking methodology,the quality control processes of cleaning and disinfection of bronchofiberscopes and the tracking routes were determined.The quality control process of cleaning and disinfection of bronchofiberscopes were evaluated,the existing risks were found out,and the specific improvement measures were formulated.RESULTS The onsite tracking was carried out for the incident of carbapenem-resistant Klebsiella pneumoniae(CRKP)that was caused by the contamination of 12 BALF specimens from pediatrics department wards before and after Nov.1,2021.No.2180014C bronchofiber-scope without biological surveillance was determined as the high-risk point of contamination of BALF specimens,the monitoring procedure of cleaning and disinfection of the bronchofiberscopes was revised.The BALF specimens that were submitted from Dec.1,2021 to Dec.31,2021 were tracked,and no CRKP was detected among the 23 submitted specimens.Totally 12 bronchofiberscope specimens were collected for biological surveillance,and the qualified rate was 100.00％.The treatment rooms of pediatrics department,hand disinfection effect of health care workers of cleaning and disinfection rooms and disinfection effect of object surfaces were monitored,and the quali-fied rate was increased from 98.39％to 100.00％.CONCLUSIONS The tracking methodology is an effective tool for quality management and can be used for evaluation of quality process of cleaning and disinfection of bronchofi-berscopes,which may find out the causes for adverse events in a timely manner and raise the medical safety.

Objective To investigate the correlation between serum amyloid A(SAA)level and disease se-verity in children infected with severe acute respiratory syndrome coronavirus 2(COVID-19).Methods A to-tal of 116 children infected with COVID-19 admitted to the Department of Pediatrics of the hospital from De-cember 2022 to April 2023 were included and divided into asymptomatic/mild group and moderate/severe group according to the severity of the disease.In addition,65 healthy children who received health examination during the same period were selected as the control group.Serum SAA levels in children in acute stage and convalescent stage were detected by enzyme-linked immunosorbent assay.Results Compared with the control group,the serum SAA level in the children infected with COVID-19 was significantly increased in the acute stage(P＜0.05).The area under the receiver operating characteristic(ROC)curve(AUC)of SAA levels in the acute stage for diagnosing children with COVID-19 infection was 0.926(95％CI:0.886-0.966).In SARS-CoV-2 infected children,the SAA levels in the acute stage in the asymptomatic/mild group and the moderate/severe group were 2.71(1.29-10.86)mg/L and 37.78(18.58-92.62)mg/L,the differences were statistically significant between the two groups(Z=5.782,P＜0.001).In addition,serum SAA was pos-itively correlated with severity of SARS-CoV-2 by Spearman analysis(r=0.657,P＜0.001).Serum SAA lev-els were also significantly positively correlated with C-reactive protein(CRP),immunoglobulin(Ig)M,IgG,IgA and neutralizing antibody(NAb)in acute stage(P＜0.05).The AUC of serum SAA level in acute stage for diagnosing the moderate/severe children with SARS-CoV-2 was 0.889(95％CI:0.842-0.955),which was higher than that of CRP(P＜0.05).Compared with serum antibodies(IgM,IgG,IgA and NAb),the rate of serum SAA positive(≥5.55 mg/L)in children in acute stage was significantly higher(P＜0.05).The positive rate of serum SAA in convalescent children was significantly lower than that of serum antibody(P＜0.05).Conclusion Elevated serum SAA in acute phase is associated with increased risk of SARS-CoV-2 infec-tion and disease severity in children.Serum SAA is promising as a good biomarker for monitoring SARS-CoV-2 infection and severity in children.

Objective:To explore the relationship between 23S rRNA domain V locus mutations in mycoplasma pneumoniae (MP) and the clinical characteristics plus macrolide resistance in pediatric MP pneumonia.Methods:A retrospective analysis was conducted on 220 children with MP pneumonia admitted to the Xi′an Central Hospital from January 2021 to June 2024. Patients were divided into a mutation group and a non-mutation group according to the presence or absence of point mutations at positions 2063, 2064, 2067 and 2617 within the 23S rRNA domain V. General data, clinical features [disease course, fever duration, length of hospital stay, time to resolution of chest X-ray infiltrates, pleural effusion, pulmonary parenchymal lesions, white blood cell count (WBC), lactate dehydrogenase (LDH), MP-DNA load] and macrolide resistance were compared between the two groups.Results:Among the 220 enrolled patients, 114 were assigned to the mutation group and 106 to the non-mutation group. Mutations detected in the 23S rRNA domain V were A2063 ( n=107), C2617 ( n=2), A2064 ( n=2) and A2067 ( n=0); three patients had combined A2063+ A2064 mutations. The proportion of severe pneumonia was higher in the mutation group ( P<0.05). Compared with the non-mutation group, the mutation group exhibited longer disease course, fever duration, hospital stay and time to resolution of chest X-ray infiltrates; higher rates of pleural effusion; and higher LDH levels and MP-DNA loads (all P<0.05). Both groups showed the highest resistance to first-generation macrolides (erythromycin, erythromycin ethylsuccinate, erythromycin stearate) and the highest sensitivity to third-generation macrolides (telithromycin, josamycin). Resistance rates to first-and second-generation macrolides were significantly higher in the mutation group (all P<0.05). Conclusions:Mutations in the 23S rRNA domain V of MP are closely associated with clinical severity in pediatric MP pneumonia, and patients harboring these mutations display higher rates of macrolide resistance.

OBJECTIVE To explore the effect of tracking methodology on investigation of contamination incidents of bronchoalveolar lavage fluid(BALF)specimens from the children.METHODS The onsite tracking was carried out for the contamination incidents of BALF specimens of the children through the tracking methodology,the quality control processes of cleaning and disinfection of bronchofiberscopes and the tracking routes were determined.The quality control process of cleaning and disinfection of bronchofiberscopes were evaluated,the existing risks were found out,and the specific improvement measures were formulated.RESULTS The onsite tracking was carried out for the incident of carbapenem-resistant Klebsiella pneumoniae(CRKP)that was caused by the contamination of 12 BALF specimens from pediatrics department wards before and after Nov.1,2021.No.2180014C bronchofiber-scope without biological surveillance was determined as the high-risk point of contamination of BALF specimens,the monitoring procedure of cleaning and disinfection of the bronchofiberscopes was revised.The BALF specimens that were submitted from Dec.1,2021 to Dec.31,2021 were tracked,and no CRKP was detected among the 23 submitted specimens.Totally 12 bronchofiberscope specimens were collected for biological surveillance,and the qualified rate was 100.00％.The treatment rooms of pediatrics department,hand disinfection effect of health care workers of cleaning and disinfection rooms and disinfection effect of object surfaces were monitored,and the quali-fied rate was increased from 98.39％to 100.00％.CONCLUSIONS The tracking methodology is an effective tool for quality management and can be used for evaluation of quality process of cleaning and disinfection of bronchofi-berscopes,which may find out the causes for adverse events in a timely manner and raise the medical safety.

Objective:To explore the relationship between 23S rRNA domain V locus mutations in mycoplasma pneumoniae (MP) and the clinical characteristics plus macrolide resistance in pediatric MP pneumonia.Methods:A retrospective analysis was conducted on 220 children with MP pneumonia admitted to the Xi′an Central Hospital from January 2021 to June 2024. Patients were divided into a mutation group and a non-mutation group according to the presence or absence of point mutations at positions 2063, 2064, 2067 and 2617 within the 23S rRNA domain V. General data, clinical features [disease course, fever duration, length of hospital stay, time to resolution of chest X-ray infiltrates, pleural effusion, pulmonary parenchymal lesions, white blood cell count (WBC), lactate dehydrogenase (LDH), MP-DNA load] and macrolide resistance were compared between the two groups.Results:Among the 220 enrolled patients, 114 were assigned to the mutation group and 106 to the non-mutation group. Mutations detected in the 23S rRNA domain V were A2063 ( n=107), C2617 ( n=2), A2064 ( n=2) and A2067 ( n=0); three patients had combined A2063+ A2064 mutations. The proportion of severe pneumonia was higher in the mutation group ( P<0.05). Compared with the non-mutation group, the mutation group exhibited longer disease course, fever duration, hospital stay and time to resolution of chest X-ray infiltrates; higher rates of pleural effusion; and higher LDH levels and MP-DNA loads (all P<0.05). Both groups showed the highest resistance to first-generation macrolides (erythromycin, erythromycin ethylsuccinate, erythromycin stearate) and the highest sensitivity to third-generation macrolides (telithromycin, josamycin). Resistance rates to first-and second-generation macrolides were significantly higher in the mutation group (all P<0.05). Conclusions:Mutations in the 23S rRNA domain V of MP are closely associated with clinical severity in pediatric MP pneumonia, and patients harboring these mutations display higher rates of macrolide resistance.

Objective To explore the effect of controlled low central venous pressure(CLCVP)on venous congestion and postoperative acute kidney injury(AKI)in cardiac surgery under cardiopulmonary bypass(CPB).Methods A total of 137 patients scheduled for elective cardiac surgery under general anes-thesia with CPB were selected,including 73 males and 64 females,aged 18 to 70 years,with a BMI of 20 to 28 kg/m2,and ASA physical status Ⅱ or Ⅲ.The patients were randomly assigned into two groups:the controlled low central venous pressure group(group CL,n=68)and the control group(group C,n=69).In group CL,CLCVP was applied by pumping nitroglycerin to reduce CVP to below 10 mmHg after 20 minutes of CPB cessation until the end of surgery.If necessary,norepinephrine was applied to maintain MAP≥65 mmHg.Patients in group C received standardized anesthesia management.Urine samples were collected before anesthesia induction and 12 hours postoperatively to detect the concentration of kidney injury molecule-1(KIM-1).Urine samples were also collected before anesthesia induction and 2 hours postopera-tively to detect the concentration of neutrophil gelatinase-associated lipocalin(NGAL).Cumulative time a-bove 10,12,16,and 20 mmHg and time-weighted average CVP were used to assess venous congestion.The occurrence of postoperative AKI,stage 2 or above AKI,renal replacement therapy(CRRT),postoperative low cardiac output syndrome(LCOS),acute kidney injury following cardiac surgery(AKICS)score when arriving in ICU,in-hospital mortality,ICU stay,and postoperative hospital stay were recorded.Results Compared with group C,the cumulative time of CVP above 10,12,16,and 20 mmHg after CPB in group CL was significantly shorter,and the time-weighted average CVP was significantly lower(P＜0.05).AKI occurred in 9 patients(13.2%)in group CL and 15 patients(21.7%)in group C postoperatively,and there was no significant difference between the two groups.One case(1.5%)of stage 2 or above AKI oc-curred in group CL and 2 patients(2.9%)in group C,with one patient in group C requiring CRRT.Com-pared with group C,the concentrations of KIM-1 at 12 hours postoperatively and NGAL at 2 hours postoper-atively were significantly lower in group CL(P＜0.05).There were no statistically significant differences between the two groups in LCOS,AKICS score,in-hospital mortality,ICU stay,and postoperative hospital stay.Conclusion Controlled low central venous pressure in cardiac surgery under cardiopulmonary bypass can reduce venous congestion and decrease the occurrence of postoperative renal injury,thereby exerting a certain renal protective effect.

Objective:To investigate the risk factors of proteinuria in patients with hypertension in Qinghai-Tibet Plateau.Methods:From March 2019 to June 2020, prospective design was used to collect data of Qinghai-Tibet Plateau hypertension patients who were eligible for continuous enrollment in the Department of Cardiovascular Medicine in Hospital of Chengdu Office of People's Government of Tibet Autonomous Region. Questionnaire survey, physical examination and blood pressure measurement were performed on the selected patients. Fasting venous blood samples were collected for liver function test, blood lipid test, blood glucose test, and hemoglobin test, etc. Three times of morning urine samples were taken on different days, and urine protein creatinine ratio (UACR) was measured, UACR < 30 mg/g was negative for urinary protein, and UACR≥30 mg/g was positive for urinary protein. At the same time, the selected patients were examined by carotid artery color ultrasound and heart color ultrasound. The risk factors of proteinuria were analyzed.Results:A total of 588 patients with hypertension met the inclusion criteria, including 472 patients (80.3%) who received antihypertensive drug therapy, 239 patients (40.6%) had antihypertensive treatment compliance, and 252 patients (42.9%) reached the standard blood pressure after theropy. Hypertension was associated with diabetes mellitus in 150 patients (25.5%), and urinary protein was positive in 126 patients (21.4%). In univariate analysis, ethnic composition, systolic blood pressure [(138.19 ± 19.65) vs (133.16 ± 18.45) mmHg, 1 mmHg = 0.133 kPa], diastolic blood pressure [(85.80 ± 13.51) vs (83.17 ± 12.19) mmHg], uric acid [(411.79 ± 101.54) vs (379.96 ± 102.18) μmol/L], hemoglobin [(152.86 ± 30.70) vs (143.49 ± 21.15) g/L], pulmonary artery trunk width [(21.76 ± 3.94) vs (20.98 ± 3.34) mm], and ventricular septal thickness [(9.90 ± 1.70) vs (9.47 ± 1.60) mm] in the positive group ( n = 126) were significantly higher than those in the negative group ( n = 462, P < 0.01 or < 0.05). In multivariate logistic regression analysis, increased systolic blood pressure [odds ratio ( OR) = 1.015, 95% confidence interval (95% CI): 1.005 - 1.026], uric acid ( OR = 1.003, 95% CI: 1.001 - 1.005), and pulmonary artery trunk width ( OR = 1.058, 95% CI: 1.001 - 1.118) were risk factors for proteinuria; Tibetans had a decreased risk of proteinuria compared with Han ( OR = 0.505, 95% CI: 0.317 - 0.805), but increased hemoglobin had an increased risk of proteinuria compared with normal hemoglobin ( OR = 1.890, 95% CI: 1.231 - 2.903). Conclusion:In patients with hypertension at high altitude, increased hemoglobin, systolic blood pressure, uric acid, pulmonary artery trunk width, and Han nationality are risk factors for proteinuria.