BACKGROUND:Magnetic resonance imaging is the gold standard for the diagnosis of osteonecrosis of femoral head,and previous methods of predicting osteonecrosis of femoral head collapse based on magnetic resonance images mostly require the combined assessment of coronal and sagittal images.However,osteonecrosis of femoral head tends to occur bilaterally,most hospitals perform bilateral hip magnetic resonance imaging scans during clinical examinations,but the bilateral hip scans can only view coronal and cross-sectional images,and it is difficult to obtain sagittal images,which affects the assessment of the risk of collapse.Therefore,it is of clinical value to establish a method to assess the risk of early osteonecrosis of femoral head collapse by applying the images that can be obtained after bilateral hip magnetic resonance scanning. OBJECTIVE:To establish a method of applying coronal and cross-sectional images of bilateral hip magnetic resonance imaging to assess the risk of osteonecrosis of femoral head collapse. METHODS:The medical records of 111 patients(181 hips)with early-stage osteonecrosis of femoral head diagnosed at the outpatient clinic of Honghui Hospital Affiliated to Xi'an Jiaotong University from October 2017 to October 2019 were retrospectively analyzed.They were categorized into collapsed and non-collapsed groups according to the femoral head collapse at the final follow-up,with 69 hips in the collapsed group and 112 hips in the non-collapsed group.The angle of necrotic range on the images of median coronal plane,transverse plane or one level above and below it was measured on the magnetic resonance imaging system.The sum of the two angles of necrotic angle on the coronal and transverse planes was used as the combined necrotic angle.The average of the three combined necrotic angles of each hip was taken to get the average combined necrotic angle of each hip.Finally,the correlation between the three combined necrotic angles and the average combined necrotic angle with the collapse of osteonecrosis of femoral head was analyzed,and the specificity and sensitivity of the four combined necrotic angles in predicting collapse were evaluated by using receiver operating characteristic curves. RESULTS AND CONCLUSION:(1)Totally 69 hips(38.1%)had femoral head collapse at the last follow-up and were included in the collapsed group;112 hips(61.9%)did not have progression of collapse and were included in the non-collapsed group.(2)The difference between the collapsed group and the non-collapsed group in terms of Association Research Circulation Osseous(ARCO)stage was significant(P<0.001).The difference in age,body mass index,follow-up time,gender distribution,side of onset,and causative factors was not significant(P>0.05).(3)The results of independent samples t-test suggested that all four combined necrotic angles were significantly correlated with collapse(P<0.000 1);and the differences in combined necrotic angles between the collapsed group and the non-collapsed group of ARCO stage I and the two groups of ARCO stage II were all significant(P<0.000 1).(4)In the analysis of the receiver operating characteristic,the area under the curve of the average combined necrotic angle was greater than that of the combined necrotic angle on the lower level of the median,the middle level,and the upper level of the median.(5)The average combined necrotic angle had a higher accuracy in the prediction of collapse than the lower level of the median,the middle level,and the upper level of the combined necrotic angle.(6)It is concluded that the accuracy of the average combined necrotic angle in predicting the risk of osteonecrosis of femoral head collapse is higher,and the clinical practicability is stronger,so we can consider using this method to predict the risk of osteonecrosis of femoral head collapse.

Objective:To investigate the correlation of the emm genotypes and virulence genes with the isolation sites of Group A Streptococcus (GAS). Methods:It was a retrospective study.The specimens were collected from children with impetigo in Beijing Children′s Hospital, Capital Medical University from 2006 to 2008 for GAS isolation and identification.A total of 24 GAS strains were isolated from 16 children with impetigo, among which 7 pairs of strains were isolated from the throat and skin of 7 children, and 1 pair of strains was isolated from the vulva and skin of one child, and the remaining 8 GAS strains were isolated from the skin pus samples of 8 children.Polymerase chain reaction was applied to detect the emm genotypes and 13 virulence genes ( speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa). The correlation of the emm genotypes and virulence genes with the isolation sites of GAS strains was analyzed. Results:In this study, four emm genotypes were detected, including emm1.0 (15/24), emm12.0 (4/24), emm22.0 (2/24) and emm160.0 (1/24), and one subtype emm12.19 (2/24) was detected as well.The carrying rates of 13 virulence genes speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were 58.3%, 100%, 91.7%, 100%, 50.0%, 12.5%, 54.2%, 66.7%, 16.7%, 25.0%, 12.5%, 100% and 91.7%, respectively.All strains carried 5 to 11 virulence genes and they all carried speB, speF and smeZ.There were significant differences in the carrying rate of speA and speJ among the strains with different emm genotypes (all P<0.05). There was no significant difference in the distribution of virulence genes between skin isolates and pharyngeal isolates, including the 5 pairs of strains carrying the emm1.0 genotype (all P>0.05). Conclusions:The distribution of virulence gene of GAS in children with impetigo is significantly correlated with the emm genotype, rather than the isolation site.

BACKGROUND:For non-traumatic osteonecrosis of the femoral head,if the femoral head collapses,it will have a great impact on the normal life of the patients.Thus,it is necessary to use an appropriate way to evaluate the risk of femoral head collapse and then to take targeted measures to delay the process of femoral head collapse. OBJECTIVE:To analyze the natural course of early osteonecrosis of the femoral head(without collapse)under different locations of necrotic lesions. METHODS:121 patients(191 hips)with early non-traumatic osteonecrosis of the femoral head who were treated in the Outpatient Department of Honghui Hospital Affiliated to Xi'an Jiaotong University from October 2016 to October 2017 were enrolled in this study.The clinical data of all patients were followed up for 5 years to observe the collapse of osteonecrosis of the femoral head and the risk coefficient of femoral head collapse among different JIC types.The collapse rate of osteonecrosis of the femoral head was calculated during the follow-up. RESULTS AND CONCLUSION:(1)A total of 191 hips were included in this study.The femoral head collapsed in 86 hips during follow-up,with a total collapse rate of 45.0%.Among the influencing factors,age,ARCO stage and JIC classification were the main influencing factors of femoral head collapse(P<0.05),but body mass index,sex,incidence side and pathogenic factors were not the main influencing factors(P>0.05).(2)Among 191 hips,in JIC classification,the total collapse rates of type A,type B,type C1 and type C2 were 11.1%(2/18),30.2%(16/53),52.4%(43/82),and 65.8%(25/38),respectively.There were significant differences in the total collapse rate of the femoral head among all types(P<0.05).The collapse risk results showed that the collapse risk of type B,type C1 and type C2 was 2.41,5.22 and 7.89 times higher than that of type A,respectively.(3)Both JIC classification and ARCO stage were correlated with femoral head collapse(P<0.01).There was no significant difference in the collapse rate of the femoral head among all JIC types in ARCO I stage hips(P>0.05).In the hips with ARCO II stage,the collapse rates of the femoral head of JIC types A,B,C1 and C2 were 1.2%,19.5%,50.0%and 29.3%,respectively,and there were significant differences in the collapse rates among different types(P<0.05).(4)During follow-up,the collapse rates of the femoral head in the first to fifth years were 29.3%,7.9%,4.7%,2.6%and 0.5%,respectively.(5)Results showed that for early non-traumatic osteonecrosis of the femoral head,the risk of collapse of osteonecrosis of the femoral head is high within one year,and the location of the focus of osteonecrosis affects the risk of collapse of the femoral head.The effect of the location of the focus on the prognosis of the disease should be considered in clinical treatment.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative 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:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

OBJECTIVE To investigate the effect of individualized repositioning maneuver in the treatment of posterior semicircular canal benign paroxysmal positional vertigo(PC-BPPV)with limited neck movement.METHODS There were 163 patients with PC-BPPV admitted to the Department of Otolaryngology of Xiaolan People's Hospital of Zhongshan from January,2019 to July,2022 who were selected and divided into observation group(57 cases)and control group(106 cases)according to whether there was neck movement limitation or not.The control group was divided into control group 1(51 cases)and control group 2(55 cases)based on different reduction methods.The control group 1 were treated with modified Epley maneuver,and the observation group and the control group 2 were treated with individualized Epley maneuver.The cure rate and effective rate were compared among the three groups.The scores of vestibular symptom index(VSI),Berg balance scale(BBS)and the dimension scores of vertigo handicap inventory(DHI)were compared among the three groups before and after treatment.RESULTS There was no significant difference in the cure rate(84.37%vs.81.82%vs.80.70%)and effective rate(11.76%vs.10.91%vs.12.28%)among the three groups(P>0.05).After treatment,the scores of each dimension of VSI and DHI of PC-BPPV patients of the three groups decreased(P<0.01),and the scores of BBS increased(P<0.01),and there was no statistically significant difference in the scores of VSI(23.19±3.88 vs.23.70±4.01 vs.23.46±3.92),BBS(45.56±5.02 vs.45.14±4.98 vs.44.84±5.11)and each dimension of DHI among the three groups(P>0.05),respectively.CONCLUSION The individual Epley maneuver can effectively improve the vertigo status of patients with PC-BPPV with limited neck movement.

The monkeypox epidemic has re-emerged and is at a stage of rapid development in Africa.It is rare that has been designated as a public health emergency of international concern twice in just 2 years since May 2022, which fully demonstrates the urgency of the current monkeypox epidemic.This outbreak is caused by a new monkeypox variant strain Ⅰb.It has a faster transmission rate and may have a higher fatality rate, especially in children.Therefore, medical staff, especially pediatricians, should attach great importance to this strain, do a good job in epidemic surveillance and strengthen vaccine research and development.Nip it in the bud.

Objective To analyze the characteristics of time in range(TIR)and its relationship with oxidative stress(OS)and insulin resistance status(HOMA-IR)in patients with type 2 diabetes mellitus(T2DM)and sleep apnea-hypopnea syndrome(OSAHS).Methods According to apnea-hypopnea index(AHI),165 T2DM in patients were divided into simple T2DM group(AHI<5 times/h,n=43),T2DM combine OSAHS mild group(OSAHS-G,5≤AHI<15 times/h,n=51),T2DM combined OSAHS moderate group(OSAHS-M,15≤AHI≤30 times/h,n=40)and T2DM combine OSAHS severe group(OSAHS-S,AHI>30 times/h,n=31).TIR was calculated by dynamic blood glucose monitoring.Superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and other indexes were detected and analyzed.Results Compared with simple T2DM group,the levels of HOMA-IR,8-iso-PGF2a and Ox-LDL were higher in T2DM combined OSAHS-G,OSAHS-M or OSAHS-S group,while the levels of TIR,SOD and GSH-Px were lower(P<0.05).Pearson correlation analysis showed that TIR was positively correlated with the levels of SOD and GSH-Px(P<0.05 or P<0.01),and negatively correlated with the levels of 8-iso-PGF2a,Ox-LDL,HbA1c,HOMA-IR and the severity of OSAHS(P<0.01).Logistic regression analysis showed that TIR,SOD and GSH-Px were protective factors for severe OSAHS in T2DM patients,while 8-iso-PGE2a and Ox-LDL were the risk factors for severe OSAHS.Conclusions The glucose level fluctuates greatly in patients with T2DM and OSAHS.Insulin resistance and oxidative stress are factors that affect the normalization of TIR.

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.

Recently, there have been outbreaks of Group A Streptococcus (GAS) infection in foreign countries.The reasons are varied.With the relaxation of control for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) infection, it is very likely that concurrent or secondary GAS infection peaks will occur at the same time as the number of Corona Virus Disease 2019(COVID-19) cases increases dramatically.Children are generally susceptible to GAS and are more vulnerable.In response to possible outbreaks, early identification of GAS infections and rational use of antibiotics are particularly important.

China has classified the Corona Virus Disease 2019(COVID-19) as a statutory category B infectious disease and managed it according to Category B since January 8, 2023.In view that Omicron variant is currently the main epidemic strain in China, in order to guide the treatment of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) infection in children with the times, refer to the Diagnosis and Treatment Protocol for Novel Coronavirus Infection (Trial 10 th Edition), Expert Consensus on Diagnosis, Treatment and Prevention of Novel Coronavirus Infection in Children (Fourth Edition) and the Diagnosis and Treatment Strategy for Pediatric Related Viral Infections.The Expert Consensus on the Diagnosis, Treatment and Prevention of Novel Coronavirus Infection in Children (Fifth Edition) has been formulated and updated accordingly on related etiology, epidemiology, pathogenic mechanism, clinical manifestations, auxiliary examination, diagnosis and treatment, and added key points for the treatment of COVID-19 related encephalopathy, fulminating myocarditis and other serious complications for clinical reference.