OBJECTIVE: To explore effectiveness of TiRobot-assisted screw implantation in the treatment of coracoid process fractures of the scapula. METHODS: A retrospective analysis was conducted on the clinical data from 24 patients with coracoid process fractures of the scapula admitted between September 2019 and January 2024 and met selection criteria. Among them, 12 patients underwent TiRobot-assisted screw implantation (robot group) and 12 underwent manual screw implantation (control group) during internal fixation. There was no significant difference ( P>0.05) in baseline data such as gender, age, body mass index, disease duration, cause of injury, coracoid process fracture classification, and proportion of patients with associated injuries between the two groups. The incision length, operation time, intraoperative blood loss, hospital stay, accuracy of screw placement, coracoid process fracture healing time, and complications were recorded and compared, as well as pain visual analogue scale (VAS) score, and Constant-Murley score at last follow-up. RESULTS: The intraoperative blood loss and incision length in the robot group were significantly lower than those in the control group ( P<0.05); however, there was no significant difference in operation time and hospital stay between the two groups ( P>0.05). All patients were followed up 8-27 months (mean, 17.5 months), and the difference in follow-up time between the two groups was not significant ( P>0.05). At last follow-up, the VAS score for shoulder pain in the robot group was signifncatly lower compared to the control group, and the Constant-Murley score was significantly higher ( P<0.05). In the robot group, 16 screws were implanted intraoperatively, while 13 screws were implanted in the control group. Radiographic re-evaluation showed that the excellent and good rate of screw implantation was higher in the robot group (93.8%, 15/16) than in the control group (61.5%, 8/13), but the difference in the precision of screw implantation between the two groups was not significant ( P>0.05). Four patients in the robot group and 1 in the control group achieved double screws fixation; however, the difference in achieving double screws fixation between the two groups was not significant ( P>0.05). All fractures healed in both groups with 1 case of malunion in the control group. There was no significant difference in healing time between the two groups ( P>0.05). During follow-up, 1 patient in the control group experienced screw loosening and displacement. There was no significant difference in the incidence of screw loosening and fracture malunion between the two groups ( P>0.05). CONCLUSION Compared with manual screw implantation, TiRobot-assisted minimally invasive treatment of coracoid process fractures of the scapula can reduce intraoperative blood loss, shorten incision length, alleviate pain, and obtain better promote shoulder joint functional recovery.
Humans ; Male ; Female ; Retrospective Studies ; Fracture Fixation, Internal/instrumentation* ; Minimally Invasive Surgical Procedures/instrumentation* ; Adult ; Middle Aged ; Fractures, Bone/surgery* ; Bone Screws ; Coracoid Process/surgery* ; Robotic Surgical Procedures/methods* ; Scapula/surgery* ; Treatment Outcome ; Operative Time ; Young Adult ; Length of Stay ; Blood Loss, Surgical

OBJECTIVE: To investigate the effectiveness of 5G remote robotic surgery in the treatment of pelvic fractures. METHODS: A retrospective analysis was conducted on the clinical data of 160 patients with pelvic fractures admitted between July 2023 and June 2024 who met the selection criteria. Among these patients, 80 underwent internal fixation surgery with the assistance of 5G remote robotic surgery (5G group), while 80 received local robotic surgical assistance (control group). Baseline characteristics, including gender, age, body mass index, disease duration, cause of injury, and fracture classification, were compared between the two groups, and no significant difference was found ( P>0.05). The incision length, operation time, intraoperative blood loss, hospital stay, accuracy of screw placement, maximum residual displacement postoperatively, quality of fracture reduction, incidence of complications, Majeed pelvic function score and classification at last follow-up were recorded and compared between the two groups. RESULTS: In the 5G group, 180 screws were implanted during surgery, while 213 screws were implanted in the control group. The 5G group demonstrated significantly reduced intraoperative blood loss and shorter incision length compared to the control group ( P<0.05). No significant difference was observed between the two groups in terms of operation time or hospital stay ( P>0.05). Radiographic evaluation revealed excellent and good reduction rates of 98.8% (79/80) in the 5G group and 97.5% (78/80) in the control group, while excellent and good screw placement accuracy rates were 98.3% (177/180) in the 5G group and 95.8% (204/213) in the control group. No significant difference was found between the two groups in maximum residual displacement, reduction quality, or screw placement accuracy ( P>0.05). All patients were followed up 7-16 months (mean, 11.3 months), with no significant difference in follow-up duration between the groups ( P>0.05). No perioperative or follow-up complication, such as wound infection, iatrogenic fractures, iatrogenic neurovascular injury, screw loosening or breakage, or nonunion, were observed in either group. The control group exhibited a worse degree of gait alteration compared to the 5G group ( P<0.05), while no significant difference was found in incidences of squatting limitation or persistent pain ( P>0.05). At last follow-up, no significant difference was observed between the groups in Majeed pelvic function scores or grading ( P>0.05). CONCLUSION Compared with the local surgery group, 5G remote robotic surgery supported by remote expert technical guidance demonstrated smaller incision lengths, less intraoperative blood loss, and fewer postoperative complications, and was shown to be a precise, minimally invasive, safe, and reliable surgical method.
Humans ; Robotic Surgical Procedures/instrumentation* ; Pelvic Bones/surgery* ; Male ; Retrospective Studies ; Fracture Fixation, Internal/instrumentation* ; Female ; Fractures, Bone/surgery* ; Middle Aged ; Bone Screws ; Adult ; Operative Time ; Treatment Outcome ; Blood Loss, Surgical ; Length of Stay ; Postoperative Complications/epidemiology* ; Aged ; Young Adult

OBJECTIVE: To investigate the effectiveness of TiRobot-assisted minimally invasive treatment for fragility fractures of the pelvis (FFP) in elderly patients. METHODS: A retrospective analysis was conducted on the clinical data of 176 patients with FFP who were admitted between July 2018 and July 2024 and met the selection criteria. Among them, 95 patients underwent TiRobot-assisted closed reduction and minimally invasive cannulated screw fixation (robot group), while 81 patients underwent traditional open reduction and plate screw fixation (control group). There was no significant difference in baseline data such as gender, age, fracture classification, disease duration, and preoperative visual analogue scale (VAS) pain scores between the two groups ( P>0.05). The following parameters were recorded and compared between the two groups, including operation time, intraoperative blood loss, intraoperative transfusion rate, volume of intraoperative blood transfusion, maximum incision length, hospital stay, maximum residual displacement, reduction quality, fracture healing time, incidence of complications, VAS scores, Majeed pelvic function scores, and functional grading. RESULTS: All surgeries in both groups successfully completed. The robot group exhibited significantly shorter operation time, reduced intraoperative blood loss, lower intraoperative transfusion rate, smaller volume of intraoperative blood transfusion, shorter maximum incision length, and shorter hospital stay compared to the control group ( P<0.05). In the robot group, a total of 14 INFIX internal fixation frames and 280 cannulated screws were implanted, among which 250 screws were rated as excellent, 17 as good, and 13 as poor, resulting in a screw placement excellent and good rate of 95.36%. Radiological review revealed that the excellent and good rate of reduction quality was in 91.58% (87/95) in the robot group and 81.48% (66/81) in the control group, with no significant difference in postoperative maximum residual fracture displacement or reduction quality between the two groups (P>0.05). All patients in both groups were followed up 12-66 months, with an average of 28.9 months, and there was no significant difference in follow-up time between the two groups ( P>0.05). The fracture healing time in the robot group was significantly shorter than that in the control group ( P<0.05). At last follow-up, both groups showed significant improvement in VAS scores compared to preoperative values ( P<0.05); the change values of VAS scores, Majeed scores, and the excellent and good rate of Majeed pelvic function were significantly higher in the robot group than in the control group ( P<0.05). Regarding postoperative complications, there was no significant difference between the two groups in terms of gait changes, secondary surgeries, heterotopic ossification, incision infections, walking difficulties, internal fixation failure, or mortality rates ( P>0.05); however, the incidence of delayed wound healing was significantly lower in the robot group than in the control group ( P<0.05). CONCLUSION TiRobot-assisted minimally invasive treatment of elderly FFP is superior to traditional open reduction and internal fixation in terms of surgical trauma control, postoperative rehabilitation speed, and functional recovery.
Humans ; Male ; Retrospective Studies ; Female ; Minimally Invasive Surgical Procedures/instrumentation* ; Fracture Fixation, Internal/instrumentation* ; Pelvic Bones/surgery* ; Aged ; Bone Screws ; Bone Plates ; Robotic Surgical Procedures/methods* ; Aged, 80 and over ; Treatment Outcome ; Osteoporotic Fractures/surgery* ; Operative Time ; Blood Loss, Surgical ; Fracture Healing ; Fractures, Bone/surgery*

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective:To investigate the short-term efficacy of the intelligent robot-assisted fracture reduction system (RAFR) in the treatment of Tile-type C1-2 pelvic fractures.Methods:A retrospective study was conducted to analyze the clinical data of the 15 patients who had been treated for Tile-type C pelvic fractures at Department of Orthopedic Trauma, Foshan Hospital of Traditional Chinese Medicine between June 2022 and November 2023. The cohort were 7 males and 8 females, with an age of (51.6±22.1) years and a body mass index of (22.35±2.14) kg/m 2. According to the Tile classification, there were 9 cases of type C1 and 6 cases of type C2. The interval from injury to surgery was (11.3±3.9) days. Minimally invasive closed reduction and internal fixation of pelvic fractures were performed with the assistance of RAFR system. The anterior pelvic ring was fixed with percutaneous hollow screws from the pubic branch, and the posterior pelvic ring fixed with percutaneous hollow screws from the sacroiliac joint. If necessary, external fixation brackets and internal stent fixation technique for the anterior pelvic ring were used to enhance the stability of the pelvic ring. The frequency and time of intraoperative fluoroscopy, reduction time, surgical time, intraoperative bleeding volume, fracture reduction quality, follow-up time, fracture healing time, pelvic function recovery at the last follow-up, and incidence of complications were recorded. Results:With the assistance of RAFR system, 15 patients were all successfully treated with minimally invasive closed reduction and internal fixation for pelvic fractures. For this cohort, intraoperative fluoroscopy frequency was 31 (20, 55) times, fluoroscopy time 25.8 (18.0, 33.0) seconds, reduction time (57.7±3.5) minutes, surgical time 205 (200, 210) minutes, intraoperative bleeding volume 100 (100, 200) mL, and residual displacement (7.55±3.51) mm. According to the Matta scoring, the postoperative quality of fracture reduction was evaluated as excellent in 4 cases, as good in 8 cases, and as fair in 3 cases. Fourteen patients were followed up for 15.0 (10.8, 18.0) months after surgery, and 1 patient was lost to the follow-up. The fracture healing time for the 14 patients was 3.6 (3.2, 4.7) months. The Majeed functional score at the last follow-up was (83.4±6.4) points, giving 4 excellent and 10 good cases.Conclusion:The RAFR system can facilitate precise and minimally invasive closed reduction for the majority of patients with Tile-type C1-2 pelvic fracture, achieving satisfactory fracture reduction quality and short-term efficacy.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective:To analyze the factors affecting delayed chemotherapy in children with Burkitt lymphoma (BL) and their influence on prognosis.Methods:Retrospective cohort study. Clinical data of 591 children aged ≤18 years with BL from May 2017 to December 2022 in China Net Childhood Lymphoma (CNCL) was collected. The patients were treated according to the protocol CNCL-BL-2017. According to the clinical characteristics, therapeutic regimen was divided into group A, group B and group C .Based on whether the total chemotherapy time was delayed, patients were divided into two groups: the delayed chemotherapy group and the non-delayed chemotherapy group. Based on the total delayed time of chemotherapy, patients in group C were divided into non-delayed chemotherapy group, 1-7 days delayed group and more than 7 days delayed group. Relationships between delayed chemotherapy and gender, age, tumor lysis syndrome before chemotherapy, bone marrow involvement, disease group (B/C group), serum lactate dehydrogenase (LDH) > 4 times than normal, grade Ⅲ-Ⅳ myelosuppression after chemotherapy, minimal residual disease in the interim assessment, and severe infection (including severe pneumonia, sepsis, meningitis, chickenpox, etc.) were analyzed. Logistic analysis was used to identify the relevant factors. Kaplan-Meier method was used to analyze the patients' survival information. Log-Rank was used for comparison between groups.Results:Among 591 patients, 504 were males and 87 were females, the follow-up time was 34.8 (18.6,50.1) months. The 3-year overall survival (OS) rate was (92.5±1.1)%,and the 3-year event-free survival (EFS) rate was (90.5±1.2)%. Seventy-three (12.4%) patients were in delayed chemotherapy group and 518 (87.6%) patients were in non-delayed chemotherapy group. The reasons for chemotherapy delay included 72 cases (98.6%) of severe infection, 65 cases (89.0%) of bone marrow suppression, 35 cases (47.9%) of organ dysfunction, 22 cases (30.1%) of tumor lysis syndrome,etc. There were 7 cases of chemotherapy delay in group B, which were seen in COPADM (vincristine+cyclophosphamide+prednisone+daunorubicin+methotrexate+intrathecal injection,4 cases) and CYM (methotrexate+cytarabine+intrathecal injection,3 cases) stages. There were 66 cases of chemotherapy delay in group C, which were common in COPADM (28 cases) and CYVE 1 (low dose cytarabine+high dose cytarabine+etoposide+methotrexate, 12 cases) stages. Multinomial Logistic regression analysis showed that the age over 10 years old ( OR=0.54,95% CI 0.30-0.93), tumor lysis syndrome before chemotherapy ( OR=0.48,95% CI 0.27-0.84) and grade Ⅲ-Ⅳ myelosuppression after chemotherapy ( OR=0.55,95% CI 0.33-0.91)were independent risk factors for chemotherapy delay.The 3-year OS rate and the 3-year EFS rate of children with Burkitt lymphoma in the delayed chemotherapy group were lower than those in the non-delayed chemotherapy group ((79.4±4.9)% vs. (94.2±1.1)%, (80.2±4.8)% vs. (92.0±1.2)%,both P<0.05). The 3-year OS rate of the group C with chemotherapy delay >7 days (42 cases) was lower than that of the group with chemotherapy delay of 1-7 days (22 cases) and the non-delay group (399 cases) ((76.7±6.9)% vs. (81.8±8.2)% vs. (92.7±1.3)%, P=0.002).The 3-year OS rate of the chemotherapy delay group (9 cases) in the COP (vincristine+cyclophosphamide+prednisone) phase was lower than that of the non-chemotherapy delay group (454 cases) ((66.7±15.7)% vs. (91.3±1.4)%, P=0.005). Similarly, the 3-year OS rate of the chemotherapy delay group (11 cases) in the COPADM1 phase was lower than that of the non-chemotherapy delay group (452 cases) ((63.6±14.5)% vs. (91.5±1.3)%, P=0.001). Conclusions:The delayed chemotherapy was related to the age over 10 years old, tumor lysis syndrome before chemotherapy and grade Ⅲ-Ⅳ myelosuppression after chemotherapy in pediatric BL. There is a significant relationship between delayed chemotherapy and prognosis of BL in children.