1.Analysis of the Development and Implementation of the Environmental Damage Compensation System in Japan
Kai HE ; Jin-Long YUAN ; Chang-Mao QIU ; Ze-Jun LIU ; Yuan-Feng QI ; Zhen-Hui GAO
Journal of Forensic Medicine 2025;41(1):74-82
In the 1950s and 1960s,Japan's implementation of policies prioritizing economic develop-ment caused a lack of effective supervision over the discharge of industrial wastewater and exhaust gases,which led to the occurrence of the"Four Major Pollution Diseases",including Minamata disease,causing serious social and public health problems.To more effectively address public nuisances and pro-vide compensation to victims,the Japanese government gradually established an environmental damage compensation system with administrative relief characteristics since the 1970s.Through long-term prac-tice and system optimization,this system has evolved into a mature institutional framework with a clear division of labor and efficient collaboration.This paper systematically reviews the development process of Japan's environmental damage compensation system and deeply analyzes its legal frame-work and supporting policies,aiming to provide useful references for the construction and improve-ment of China's environmental damage compensation system.Meanwhile,through the case analysis of Minamata disease,the paper explores the specific mechanisms and effects in the compensation practices,further revealing the system's operational characteristics and implications,and providing a reference ba-sis for the construction of China's environmental governance legal system.
2.Clinical efficacy of open reduction and internal fixation with plates versus minimally invasive Kirschner wire fixation for osteoporotic Colles' fractures.
Jun-Wei ZHANG ; Jin-Yong HOU ; Zhao-Hui LI ; Zhen-Yuan MA ; Xiang GAO ; Hong-Zheng BI ; Ling-Ling CHEN ; Hai-Tao WANG ; Wei-Zhi NIE ; Yong-Zhong CHENG ; Xiao-Bing XI
China Journal of Orthopaedics and Traumatology 2025;38(1):18-24
OBJECTIVE:
To compare the short-term clinical efficacy and safety of closed reduction with Kirschner wire fixation versus open reduction with plate fixation for treating osteoporotic Colles' fractures in middle-aged and elderly patients.
METHODS:
Between January 2018 and January 2023, 119 patients with Colles fractures were retrospectively analyzed, including 39 males and 80 females, aged from 48 to 74 years old with an average of(60.58±6.71) years old. The time from injury to operation ranged 1 to 13 days with an average of (5.29±2.52) days. According to the surgical method, they were divided into Kirschner wire fixation group (Kirschner wire group) and plate internal fixation group (plate group). In Kirschner wire group, there were a total of 68 patients, comprising 21 males and 47 females. The average age was (61.15±6.24) years old, ranged from 49 to 74 years old. Among them, 41 cases involved the left side while 27 cases involved the right side. In the plate group, there were a total of 51 patients, including 18 males and 33 females. The average age was (59.78±5.71) years old ranged from 48 to 72 years old. Among them, there were 31 cases on the left side and 20 cases on the right side. The following parameters were recorded before and after the operation:operation time, intraoperative blood loss, hospitalization days, hospitalization expenses, postoperative complications, and radiographic parameters of distal radius (distal radius height, ulnar deviation angle, palmar tilt angle). The clinical efficacy was evaluated at 3 and 12 months after the operation using Gartland-Werley and disabilites of the arm shoulder and hand (DASH) scores.
RESULTS:
The patients in both groups were followed up for a duration from 12 to 19 months with an average of(13.32±2.02) months. The Kirschner wire group exhibited significantly shorter operation time compared to the plate group 27.91(13.00, 42.00) min vs 67.52(29.72, 105.32) min, Z=-8.74, P=0.00. Intraoperative blood loss was also significantly lower in the Kirschner wire group than in the plate group 3.24(1.08, 5.40) ml vs 21.91(17.38, 26.44) ml, Z=-9.31, P=0.00. Furthermore, patients in the Kirschner wire group had a shorter length of hospital stay compared to those in the plate group (8.38±2.63) days vs (11.40±2.78) days, t=-3.12, P=0.00. Additionally, hospitalization cost was significantly lower in the Kirschner wire group than in the plate group 10 111.29(6 738.98, 13 483.60) yuan vs 15 871.11(11 690.40, 20 051.82) yuan, Z=-5.62, P=0.00. The incidence of complications was 2 cases in the Kirschner wire group and 1 case in the plate group, with no statistically significant difference(P>0.05). At 3 months postoprative, the radial height of the Kirschner wire group was found to be significantly smaller than that of the plate group, with measurements of (11.45±1.69) mm and (12.11±1.78) mm respectively (t=-2.06, P=0.04). However, there were no statistically significant differences observed in ulnar deviation angle and palmar tilt angle between the two groups (P>0.05). The DASH score and Gartland-Werley score in the Kirschner group were significantly higher than those in the plate group at 3 months post-operation (19.10±9.89) vs (13.47±3.51), t=4.34, P=0.00;(11.15±3.61) vs (6.41±2.75), t=8.13, P=0.00). However, there was no significant difference between the two groups at 12 months post-operation (P>0.05).
CONCLUSION
Compared to plate internal fixation, closed reduction with Kirschner wire support fixation yields a slightly inferior recovery of radial height;however, there is no significant disparity in the functional score of the affected limb at 12 months post-operation. Nonetheless, this technique offers advantages such as shorter operation time, reduced intraoperative blood loss, decreased hospitalization duration, and lower cost.
Humans
;
Female
;
Male
;
Middle Aged
;
Aged
;
Fracture Fixation, Internal/instrumentation*
;
Bone Wires
;
Bone Plates
;
Retrospective Studies
;
Colles' Fracture/surgery*
;
Minimally Invasive Surgical Procedures/methods*
;
Open Fracture Reduction/methods*
;
Osteoporotic Fractures/surgery*
3.Comparative experimental study on the biomechanical properties of retrograde tibial nailing and distal tibia L-shaped plate in distal tibia fracture.
Xu-Ping LIN ; Qing-Jun LIU ; Sheng-Gui XU ; Cong ZHANG ; Ming-Ming GAO ; Zhen-Qi DING ; Bin LIN
China Journal of Orthopaedics and Traumatology 2025;38(7):737-742
OBJECTIVE:
To investigate the biomechanical characteristics of retrograde tibial nailing (RTN) and distal tibial L-shaped plating in the internal fixation of distal tibial fractures.
METHODS:
Fourteen fresh adult tibia specimens were selected, comprising 7 males and 7 females aged from 34 to 55 years old. The specimens were randomly divided into experimental group and control group by numerical table method with 7 specimens in each group. RTN was used for internal fixation of distal tibial fractures in the experimental group, and L-shaped plate was used for internal fixation of distal tibial fractures in the control group. The axial compression properties of the two groups of specimens were tested under the pressure of 100, 200, 300, 400, and 500 N after operation, and torsional resistance at torque levels of 1.0, 2.0, 3.0, 4.0, 5.0 N·m. The anti-fatigue performance of the specimens was tested at 500 N pressure for 3 000 and 10 000 cycles. X-ray fluoroscopy was performed to observe whether the the internal fixator was deformed and whether the screw was loosened or broken.
RESULTS:
When the pressure was 400 N and 500 N, the axial compression displacement of the experimental group was (1.11±0.06) mm and (1.24±0.05) mm, which were smaller than those of the control group (1.21±0.08) mm and (1.37±0.11) mm, and the differences were statistically signific (P<0.05). Under the pressure of 500 N, the axial compression stiffness of the experimental group was (389.24±17.79) N·mm-1, which was significantly higher than that of the control group (362.37±14.44) N·mm-1(P<0.05). When the torque was 4 and 5 N·m, the torsion angles of the experimental group were (2.97±0.23) ° and (3.41±0.17) °, which were smaller than those of the control group (3.31±0.28) ° and (3.76±0.20) °, and the differences were statistically significant (P<0.05). When the torque was 5 N·m, the torsional stiffness of the experimental group was (1.48±0.07) N·m per degree, which was higher than that of the control group (1.36±0.06) N·m per degree, and the difference was statistically significant (P<0.05). For the intragroup comparison of fatigue resistance, the differences in axial compression displacement between the two groups were not statistically significant at 3 000 and 10 000 cycles (all P>0.05). When 3 000 times and 10 000 times of compression, the axial compression displacement of the experimental group was (1.38±0.08), (1.43±0.07) mm, which was smaller than that of the control group (1.51±0.10), (1.54±0.08) mm, the differences were statistically significant (P<0.05). In the experimental group, no screw loosening, fracture or internal fixation deformation was found, while in the control group, locking screw loosening occurred in 2 models after 10 000 pressures.
CONCLUSION
The biomechanical performance of RTN is obviously better than that of the distal tibial L-shaped plate, which provides biomechanical data support for the clinical application of RTN.
Humans
;
Female
;
Male
;
Adult
;
Tibial Fractures/physiopathology*
;
Middle Aged
;
Biomechanical Phenomena
;
Bone Plates
;
Fracture Fixation, Internal/instrumentation*
;
Bone Nails
;
Tibia/surgery*
4.Effectiveness and safety of augmentative plating technique in managing nonunion following intramedullary nailing of long bones in the lower extremity: A systematic review and meta-analysis.
Cong-Xiao FU ; Hao GAO ; Jun REN ; Hu WANG ; Shuai-Kun LU ; Guo-Liang WANG ; Zhen-Feng ZHU ; Yun-Yan LIU ; Wen LUO ; Yong ZHANG ; Yun-Fei ZHANG
Chinese Journal of Traumatology 2025;28(3):164-174
PURPOSE:
To methodically assess the effectiveness of augmentative plating (AP) and exchange nailing (EN) in managing nonunion following intramedullary nailing for long bone fractures of the lower extremity.
METHODS:
PubMed, EMBASE, Web of Science, and the Cochrane Library were searched to gather clinical studies regarding the use of AP and EN techniques in the treatment of nonunion following intramedullary nailing of lower extremity long bones. The search was conducted up until May 2023. The original studies underwent an independent assessment of their quality, a process conducted utilizing the Newcastle-Ottawa scale. Data were retrieved from these studies, and meta-analysis was executed utilizing Review Manager 5.3.
RESULTS:
This meta-analysis included 8 studies involving 661 participants, with 305 in the AP group and 356 in the EN group. The results of the meta-analysis demonstrated that the AP group exhibited a higher rate of union (odds ratio: 8.61, 95% confidence intervals (CI): 4.12 - 17.99, p < 0.001), shorter union time (standardized mean difference (SMD): -1.08, 95% CI: -1.79 - -0.37, p = 0.003), reduced duration of the surgical procedure (SMD: -0.56, 95% CI: -0.93 - -0.19, p = 0.003), less bleeding (SMD: -1.5, 95% CI: -2.81 - -0.18, p = 0.03), and a lower incidence of complications (relative risk: -0.17, 95% CI: -0.27 - -0.06, p = 0.001). In the subgroup analysis, the time for union in the AP group in nonisthmal and isthmal nonunion of lower extremity long bones was shorter compared to the EN group (nonisthmal SMD: -1.94, 95% CI: -3.28 - -0.61, p < 0.001; isthmal SMD: -1.08, 95% CI: -1.64 - -0.52, p = 0.002).
CONCLUSION
In the treatment of nonunion in diaphyseal fractures of the long bones in the lower extremity, the AP approach is superior to EN, both intraoperatively (with reduced duration of the surgical procedure and diminished blood loss) and postoperatively (with an elevated union rate, shorter union time, and lower incidence of complications). Specifically, in the management of nonunion of lower extremity long bones with non-isthmal and isthmal intramedullary nails, AP demonstrated shorter union time in comparison to EN.
Humans
;
Bone Nails/adverse effects*
;
Bone Plates/adverse effects*
;
Femoral Fractures/surgery*
;
Fracture Fixation, Intramedullary/methods*
;
Fractures, Ununited/surgery*
;
Lower Extremity/injuries*
5.The Valvular Heart Disease-specific Age-adjusted Comorbidity Index (VHD-ACI) score in patients with moderate or severe valvular heart disease.
Mu-Rong XIE ; Bin ZHANG ; Yun-Qing YE ; Zhe LI ; Qing-Rong LIU ; Zhen-Yan ZHAO ; Jun-Xing LV ; De-Jing FENG ; Qing-Hao ZHAO ; Hai-Tong ZHANG ; Zhen-Ya DUAN ; Bin-Cheng WANG ; Shuai GUO ; Yan-Yan ZHAO ; Run-Lin GAO ; Hai-Yan XU ; Yong-Jian WU
Journal of Geriatric Cardiology 2025;22(9):759-774
BACKGROUND:
Based on the China-VHD database, this study sought to develop and validate a Valvular Heart Disease- specific Age-adjusted Comorbidity Index (VHD-ACI) for predicting mortality risk in patients with VHD.
METHODS & RESULTS:
The China-VHD study was a nationwide, multi-centre multi-centre cohort study enrolling 13,917 patients with moderate or severe VHD across 46 medical centres in China between April-June 2018. After excluding cases with missing key variables, 11,459 patients were retained for final analysis. The primary endpoint was 2-year all-cause mortality, with 941 deaths (10.0%) observed during follow-up. The VHD-ACI was derived after identifying 13 independent mortality predictors: cardiomyopathy, myocardial infarction, chronic obstructive pulmonary disease, pulmonary artery hypertension, low body weight, anaemia, hypoalbuminaemia, renal insufficiency, moderate/severe hepatic dysfunction, heart failure, cancer, NYHA functional class and age. The index exhibited good discrimination (AUC, 0.79) and calibration (Brier score, 0.062) in the total cohort, outperforming both EuroSCORE II and ACCI (P < 0.001 for comparison). Internal validation through 100 bootstrap iterations yielded a C statistic of 0.694 (95% CI: 0.665-0.723) for 2-year mortality prediction. VHD-ACI scores, as a continuous variable (VHD-ACI score: adjusted HR (95% CI): 1.263 (1.245-1.282), P < 0.001) or categorized using thresholds determined by the Yoden index (VHD-ACI ≥ 9 vs. < 9, adjusted HR (95% CI): 6.216 (5.378-7.184), P < 0.001), were independently associated with mortality. The prognostic performance remained consistent across all VHD subtypes (aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid valve disease, mixed aortic/mitral valve disease and multiple VHD), and clinical subgroups stratified by therapeutic strategy, LVEF status (preserved vs. reduced), disease severity and etiology.
CONCLUSION
The VHD-ACI is a simple 13-comorbidity algorithm for the prediction of mortality in VHD patients and providing a simple and rapid tool for risk stratification.
6.Delayed physical growth and related factors in pediatric patients with transfusion-dependent thalassemia
Zhexiang KUANG ; Jingyu ZHAO ; Xiao YU ; Jing XU ; Zhen GAO ; Yanjie LIU ; Anni WANG ; Jin DONG ; Hong PAN ; Lele ZHANG ; Liwei FANG ; Guibin WU ; Xinli LI ; Jun SHI ; Li XU ; Wenjun XIE
Chinese Journal of Hematology 2025;46(4):328-335
Objectives:To investigate the physical growth status of pediatric patients with transfusion-dependent thalassemia (TDT) and analyze the effects of treatment-related and socioeconomic factors on physical growth.Methods:Based on the specialized thalassemia database from gene therapy clinical research at the Institute of Hematology & Hospital of Blood Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, we collected data on height and weight development, family economic status, and medical records of 338 pediatric patients with TDT from October 2023 to May 2024. The length/height-for-age and body mass index (BMI) -for-age were classified based on the Growth Standard for Children under 7 Years of Age, Standard for Height Level Classification among Children and Adolescents Aged 7-18 Years, and Dietary Guidelines for Chinese Residents. Logistic regression analysis was conducted to assess the effects of family economic status and disease-related treatment on length/height-for-age and BMI-for-age.Results:Among the 338 patients, 118 were children and 220 were adolescents (192 males and 146 females), with a median age of 12 years (range: 0.8-18) and a median diagnosis duration of 10.3 years (range: 0.5-17.9). Subtypes included α-thalassemia [21 cases (6.2%) ], β-thalassemia [288 cases (85.2%) ], and combined αβ-thalassemia[29 cases (8.6%) ]. The monthly household income of patients was concentrated in 3 000-5 000 yuan (39.9%) and 5 001-10 000 yuan (34.9%), whereas 67.2% of the families had monthly medical expenses of <3 000 yuan. Of the patients, 75.5% received their first transfusion before 1 year of age. The proportions of children and adolescents with pretransfusion hemoglobin (HGB) of ≤70 g/L were 4.2% and 6.4%, respectively. Adolescents demonstrated significantly higher rates of transfusion frequency of <4 weeks/session, monthly red blood cell infusion of >2 U, serum ferritin (SF) of ≥5 000 μg/L, iron chelation therapy, and splenectomy compared with children (all P<0.05). Of the 338 patients, 26.0%, 22.8%, and 8.9% demonstrated stunted growth, underweight, and concurrent stunted growth with underweight, respectively. No significant difference was observed in the stunted growth rates between children (22.9%) and adolescents (27.7%) ( P=0.402). However, the underweight rate in adolescents (26.8%) was significantly higher than that in children (15.3%) ( P=0.023). The multivariate analysis determined the following risk factors for stunted growth: monthly household income of <10 000 yuan (5 001-10 000 yuan: OR=5.49, 95% CI: 1.48-35.76; 3 000-5 000 yuan: OR=6.87, 95% CI: 1.88-44.60; <3 000 yuan: OR=9.29, 95% CI: 2.20-64.77), pretransfusion HGB of ≤70 g/L ( OR=3.25, 95% CI: 1.07-10.18), and SF of ≥5 000 μg/L ( OR = 3.04, 95% CI: 1.20-7.70). Longer diagnostic duration was associated with underweight ( OR=1.10, 95% CI: 1.01-1.20) . Conclusions:Children and adolescents with TDT with pretransfusion SF of ≥5 000 μg/L, HGB of ≤70 g/L, low monthly household income, or longer diagnosis duration were significantly more likely to experience delayed physical growth.
7.Single-cell analysis of immune-lineage features in T-cell large granular lymphocytic leukemia
Ke HUANG ; Lele ZHANG ; Chen QIU ; Ruonan LI ; Yucan SHEN ; Weiwang LI ; Hong PAN ; Zhen GAO ; Liwei FANG ; Yajing CHU ; Weiping YUAN ; Jun SHI
Chinese Journal of Hematology 2025;46(5):453-459
Objective:To investigate alterations in the immune lineage of T-cell large granular lymphocytic leukemia (T-LGLL) at the single-cell transcriptome level and to elucidate its pathogenic mechanisms.Methods:Peripheral blood samples were collected from 5 T-LGLL patients before and after treatment (from June 2019 to December 2020) and 3 healthy controls at the Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC. Single-cell transcriptome sequencing libraries were prepared and sequenced using 10× Genomics technology. Differentially expressed genes in immune cells were compared between patients and healthy donors, followed by pathway enrichment analyses.Results:Profiling 67,237 immune cells revealed that, in T-LGLL: 1) Effector CD8+ T cells exhibited increased numbers, enhanced cytotoxicity, and greater proliferative capacity. Following effective immunosuppressive therapy, both the proliferative capacity and effector functions of these cells significantly decreased ( P<0.05). 2) The proportion of regulatory T (Treg) cells was reduced, accompanied by increased apoptosis. After effective immunosuppressive therapy leading to remission, Treg cell proportions increased, and apoptotic pathways were downregulated ( P<0.05). 3) Antigen-presenting cells (APCs) showed enhanced functionality. Monocytes and dendritic cells were enriched in antigen synthesis and presentation pathways, while B cells displayed increased antigen-binding capacity and were enriched in pathways related to T-cell activation ( P<0.05). 4) Natural killer (NK) cells exhibited attenuated cytotoxic function but demonstrated an enhanced regulatory capacity over T cells ( P<0.05) . Conclusions:T-LGLL patients present a characteristic immunological profile marked by an imbalance in immune homeostasis. This profile includes abnormal activation and expansion of effector CD8 + T cells, and a reduction in Treg cell numbers accompanied by functional impairment. Furthermore, APCs and NK cells were found to positively regulate T-lymphocyte activation, differentiation, and proliferation.
8.Analysis of treatment response and post-discontinuation efficacy maintenance of cyclophosphamide monotherapy in T-cell large granular lymphocytic leukemia
Lele ZHANG ; Linzhu TIAN ; Hong PAN ; Zhen GAO ; Weiwang LI ; Ruonan LI ; Jingyu ZHAO ; Jinbo HUANG ; Xin ZHAO ; Jianping LI ; Neng NIE ; Xiao YU ; Liyun LI ; Zhexiang KUANG ; Liwei FANG ; Jun SHI
Chinese Journal of Hematology 2025;46(7):631-635
Objective:To evaluate the efficacy of cyclophosphamide in patients with T-cell large granular lymphocytic leukemia (T-LGLL) and the maintenance of treatment-free remission (TFR) following drug discontinuation.Methods:Clinical data were collected from 37 patients with T-LGLL who received oral cyclophosphamide at the Regenerative Medicine Clinic of the Institute of Hematology and Blood Diseases Hospital between June 2019 and March 2024. Patient clinical characteristics, treatment efficacy, and long-term TFR were analyzed.Results:The median age of the 37 patients was 60 years (range: 37-86), and 22 (59.5%) were male. Anemia was observed in 30 patients (81.1%), and 28 (75.7%) met the diagnostic criteria for secondary pure red cell aplasia. Neutropenia occurred in 15 patients (40.5%), lymphocytosis in 11 (29.7%), and thrombocytopenia in three (8.1%). Sixteen patients (43.2%) had not received prior immunosuppressive therapy (treatment-naive group), while 21 patients (56.8%) were refractory to or had relapsed after immunosuppressive treatment (refractory/relapsed group). All patients met the treatment criteria and received oral cyclophosphamide at doses of 50-100 mg/day. Among the 36 evaluable patients, hematologic remission was achieved in 25 (69.4%), with a median time of 2.0 months (range: 0.7-7.0). There was no statistically significant difference in remission rates between the treatment-naive and refractory/relapsed groups (68.5% vs. 66.7%, P=0.589). Among the 25 patients who achieved hematologic remission, 24 discontinued cyclophosphamide. With a median follow-up of 39.0 months (range: 8.0-56.0), the median TFR duration was not reached. The estimated TFR rates were (90.87± 6.16) % at 12 months and (75.72±11.04) % at 36 months. No significant difference in TFR was observed between the treatment-naive and refractory/relapsed groups ( P=0.451) . Conclusion:Oral cyclophosphamide is effective in the treatment of T-LGLL, and patients may maintain long-term TFR following drug discontinuation.
9.Development, reliability, and validity of a treatment-related quality of life scale for Chinese patients with multiple myeloma
Chunyan SUN ; Zhen CAI ; Bing CHEN ; Lijuan CHEN ; Wenming CHEN ; Kaiyang DING ; Juan DU ; Rong FU ; Chengcheng FU ; Da GAO ; Guangxun GAO ; Yanjuan HE ; Jian HOU ; Ming JIANG ; Fei LI ; Jian LI ; Juan LI ; Zhenyu LI ; Aijun LIAO ; Jing LIU ; Jun LUO ; Jianmin LUO ; Yanping MA ; Jianqing MI ; Ting NIU ; Hongling PENG ; Yongping SONG ; Luqun WANG ; Rong ZHAN ; Xi ZHANG ; Yu HU
Chinese Journal of Hematology 2025;46(8):713-721
Objective:To develop a treatment-related quality of life scale for Chinese patients with multiple myeloma (MM) and to test its reliability and validity.Methods:The initial scale was constructed through a literature search, Delphi expert correspondence, and cognitive testing. This study conducted a preliminary survey of 379 patients with MM and a formal survey of 865 patients from the hematology departments of 155 hospitals nationwide from February 2024 to March 2024. The final scale was obtained after conducting item analysis and reliability and validity tests on the initial scale.Results:The constructed scale contains 36 items covering six domains: physiological, psychological, social, treatment side effects, general health, and others. In the preliminary survey, the Cronbach’s alpha coefficient of each item ranged from 0.597 to 0.939, and the test-retest reliability was 0.747 ( P<0.001). Exploratory factor analysis extracted eight common factors with a cumulative variance contribution of 60.058%. In the formal survey, the Cronbach’s alpha coefficient of each item ranged from 0.484 to 0.930, and the test-retest reliability was 0.835 ( P<0.001). Confirmatory factor analysis revealed a comparative fit index of 0.750, a root-mean-square error of approximation of 0.090, and a root-mean-square residual of 0.067. Conclusion:The treatment-related quality of life scale for Chinese patients with MM designed in this study exhibited good reliability and validity, reflecting the impact of treatment on the quality of life of patients. This scale can provide a reference to clinicians for assessing the disease status of patients.
10.Etiological surveillance and antimicrobial resistance analysis of Legionella pneumophila in the aqueous environment of public places in Shanghai, 2011-2020
Jun FENG ; Wei GAO ; Yuan ZHUANG ; Lingyue YUAN ; Yanxin CHEN ; Zhen XU ; Jiayuan LUO ; Yong CHEN ; Huanyu WU ; Xin CHEN ; Jing ZHANG ; Min CHEN
Chinese Journal of Epidemiology 2025;46(9):1600-1609
Objective:To understand the etiological surveillance and drug resistance characteristics of Legionella pneumophila (LP) from the aqueous environment of public places in Shanghai, from 2011 to 2020, and provide evidence for surveillance of the disease. Methods:Environmental water samples were systematically collected from public venues in urban and suburban districts of Shanghai for LP surveillance. All the identified LP isolates underwent a series of testings including serotyping, pulsed field gel electrophoresis (PFGE), sequence-based typing, and antimicrobial susceptibility testing. χ2 test or Cochran-Armitage trend tests were used for statistical analysis and for temporal resistance patterns. Results:Among 6 263 water samples, the LP-positive rate was 20.93% (1 311/6 263). The positivity rate decreased from 24.98% (287/1 149) in 2011-2012 to 20.02% (1 024/5 114) in 2013-2020 ( χ2=13.92, P<0.001), with the highest monthly positivity observed from June to August (23.79%, 745/3 132). A total of 1 365 LP strains were isolated, of which 912 were further characterized, including 10 serotypes, 149 PFGE patterns, and 33 sequence types (ST). The predominant serotype was Lp1 (86.84%, 792/912), and the dominant ST was ST752 (29.50%, 269/912). ST clustering revealed two major clonal groups CG1 and CG2, accounting for 91.12% (831/912) of the isolates. The 190 LPs involved in the drug sensitivity test showed three resistance profiles: azithromycin resistance (31.05%, 59/190), ciprofloxacin resistance (0.53%, 1/190) and azithromycin+ciprofloxacin resistance (0.53%, 1/190). Azithromycin-resistant strains were predominantly ST1 (64.41%, 38/59). The antimicrobial resistance rate showed a significant decline, from 48.65% (18/37) in 2011-2012 to 28.10% (43/153) in 2013-2020 ( χ2=9.38, P=0.002). Conclusions:Compared to from 2011 to 2012, both the positivity rate and antimicrobial resistance prevalence of LP in public aqueous environments of Shanghai exhibited an overall decline from 2013 to 2020. The predominant types of LP were serotype Lp1 and sequence type ST752, with notable high-level resistance to azithromycin. Measures as enhancing the enforcement of water safety regulations and prioritizing surveillance of azithromycin resistance in LP were recommended to mitigate public health risks.

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