Objective To investigate the risk factors for acute respiratory failure in immunocompromised patients with Pneumocystis jirovecii pneumonia(PJP).Methods Clinical data of 123 immunocompromised patients complicated with PJP hospitalized at Mengchao Hepatobiliary Hospital of Fujian Medical University from January 2021 to December 2023 were retrospectively collected and analyzed.SPSS 22.0 statistical software package was used to perform multivariate binary logistic regression analysis to identify risk factors for acute respiratory failure in PJP patients.Results Among the 123 PJP patients,77 were HIV-positive,and 46 were HIV-negative.HIV-negative PJP patients were more likely to have comorbidities such as hypertension(P＜0.001),diabetes mellitus(P＜0.001),coronary heart disease(P=0.034),chronic kidney disease(P＜0.001),chronic liver disease(P=0.019),chronic lung disease(P=0.011),and malignant tumor(P＜0.001).They were also more prone to respiratory failure(P＜0.001)and ICU admission(P＜0.001).The HIV-positive patients had significantly lower CD4+T lymphocyte counts and albumin levels(P＜0.001).Forty patients developed acute respiratory failure,and six patients died.Multivariate analysis showed that high neutrophil-to-lymphocyte ratio(NLR)(P=0.031),non-HIV infection(P=0.002),and concomitant infections with other pathogens(P＜0.001)were independent risk factors for incidence of respiratory failure.ROC curve analysis revealed that the area under the curve(AUC)was 0.686(0.584,0.789)for non-HIV infection,0.731(0.637,0.826)for concomitant infections with other pathogens,0.648(0.546,0.750)for NLR.The predicted probability was 0.845(0.778,0.912).Conclusions Non-HIV infection,high NLR,and concomitant infections with other pathogens are independent risk factors for incidence of respiratory failure in PJP patients.The panel combining these factors provides a higher predictive value for respiratory failure.Timely assessment of patient condition and early treatment are vital for better outcomes.

Objective:To investigate microstructural alterations in the optic chiasm and optic radiations of multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) based on diffusion kurtosis imaging (DKI).Methods:This study was a cross-sectional study. Retrospective analyses were conducted on the clinical and imaging data of 63 patients with relapsing-remitting MS (RRMS) and 62 patients with NMOSD diagnosed at First Affiliated Hospital of Chongqing Medical University from January 2019 to December 2023. According to the occurrence of optic neuritis (ON), they were categorized into ON-positive MS (ON+MS) group (40 cases), ON-negative MS (ON-MS) group (23 cases), ON-positive NMOSD (ON+NMOSD) group (40 cases) and ON-negative NMOSD (ON-NMOSD) group (22 cases). In addition, 40 healthy controls were enrolled during the same period. DKI data of all subjects were collected, and DKI post-processing was performed to obtain fractional anisotropy (FA), mean kurtosis (MK), axial kurtosis (AK), and radial kurtosis (RK) values of the optic chiasm and bilateral optic radiations. The scores of the mini-mental state examination (MMSE), montreal cognitive assessment (MoCA), and expanded disability status scale (EDSS) were obtained. The Kruskal-Wallis test was used to analyze the differences in DKI parameters of the optic chiasm and bilateral optic radiation among the 5 groups, and the Holm-Bonferroni method was employed for multiple comparison correction in pairwise comparisons.Results:There were statistically significant overall differences in the DKI parameters of the optic chiasm and bilateral optic radiations among healthy control group, ON+MS group, ON-MS group, ON+NMOSD group, and ON-NMOSD group (all P0.05). The FA value of the optic chiasm in ON+NMOSD group was significantly lower than that of healthy control group and ON-MS group, as well as ON-NMOSD group ( P0.05). The FA value of the left optic radiation in ON+NMOSD group was lower than that in healthy control group and the ON-MS group. The RK value of the optic chiasm in ON+MS group was lower than that in the healthy control group and ON-NMOSD group ( P0.05). The MK and RK values of the left optic radiation in ON-MS group were significantly lower than those in the ON+NMOSD group and ON-NMOSD group ( P0.05). Conclusions:NMOSD and RRMS patients demonstrate varying degrees of microstructural damage in the optic chiasm and optic radiations. Differences of DKI parameters suggest different pathological mechanisms of visual pathway damage between NMOSD and MS, which may be helpful for early detection of occult visual pathway lesions.

OBJECTIVE To investigate the analgesic effects and potential mechanisms of the partial agonist of the 5-hydroxytryptamine 1A(5-HT1A)receptor and the selective 5-HT reuptake inhibitor,viladazone(Vil),in various animal models of pain.METHODS ① Mouse acetic acid writhing test:KM mice were divided into the model group,model+morphine 10 mg·kg-1 group,and model+Vil 2,4,8 mg·kg-1 groups.Thirty minutes after ig administration of saline(model group)or corresponding drugs,each group was ip injected with a 2%acetic acid aqueous solution(0.01 mL·g-1),and the writhing frequency of the mice was observed and recorded from 5 to 20 min.② Mouse formalin pain test:KM mice were divided into the model group and model+Vil 2,4 and 8 mg·kg-1 groups.Thirty minutes after ig adminis-tration of saline(model group)or drugs,20 μL of 5%formalin solution was sc injected into the right plantar region of the mice.The licking time(the sum of the duration of licking and biting the paw)of the mice was observed and recorded during two periods:the acute phase(0-5 min after sc formalin injec-tion)and the delayed phase(15-35 min after sc formalin injection).③ Rat chronic constriction injury(CCI)of the sciatic nerve experiment:SD rats successfully examined with a paw withdrawal threshold(PWT)<5 g were randomly divided into a CCI model group and a CCI model+Vil 2,4 and 8 mg·kg-1 group.Solvent(model group)or corresponding drugs were ig administered,and the PWT of the modeled side was measured at 30,60,120 and 240 min after the first administration to evaluate the acute anal-gesic effect of Vil on mechanical pain.Then,Vil was continuously ig administered for 14 d,and the PWT was measured 1 h after Vil administration on the 7th and 14th d to evaluate the long-term analgesic effect of Vil.Immunofluorescence staining was employed to analyze the expression levels of inflamma-tion-related proteins,ionized calcium binding adapter molecule 1(IBA-1),tumor necrosis factor α(TNF-α),and interleukin 1β(IL-1β),in brain tissues.Enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of IBA-1,TNF-α and IL-1β in the dorsal root ganglion of the spinal cord in the CCI model.RESULTS ① In the mouse model of acetic acid writhing,single ig administration of morphine 10 mg·kg-1 and Vil at varied doses significantly reduced the number of writhings induced by acetic acid compared to the model group.② In the formalin-induced pain model,the average licking time of the model group was 50.5 s during the acute phase of inflammatory pain(0-5 min after intraplantar injec-tion of 5%formalin),and 347.9 s during the delayed phase of inflammatory pain(25-35 min after formalin injection).Compared to the model group,single ig administration of Vil 2-8 mg·kg-1 reduced chronic pain induced by formalin in mice,and each dose of Vil significantly decreased the licking time of mice,but had no notable impact on the licking duration exhibited by mice during acute phase.③ In the CCI model,the PWT values of CCI model rats significantly decreased compared with the control group.Pathological damage to varying extents was observed in brain slices,manifested as enlarged intercellular spaces and the appearance of vacuoles.The expression of IBA-1 in brain tissue significantly increased,while TNF-α and IL-1β hardly changed.The levels of IBA-1,TNF-α and IL-1β in the spinal dorsal root ganglion significantly increased.Compared with the CCI model,after single administration of Vil 2-8 mg·kg-1 for 60,120 and 240 min,Vil significantly reduced the PWT values.After two-week continuous administration,the PWT values in Vil 4 and 8 mg·kg-1 were significantly reduced,and Vil 2-8 mg·kg-1 could alleviate the neuropathic pain to some extent.Vil 8 mg·kg-1 significantly reduced the elevated levels of inflammatory factors compared to CCI rats.CONCLUSION The antidepressant Vil exhibits analgesic effects in mouse models of acetic acid writhing,formalin-induced inflammation,and neuropathic pain induced by CCI in rats,with a more pronounced effect on neuropathic pain.The mechanism of action may be related to the inhibition of inflammatory pathways of IBA-1.

OBJECTIVE To investigate the analgesic effects and potential mechanisms of the partial agonist of the 5-hydroxytryptamine 1A(5-HT1A)receptor and the selective 5-HT reuptake inhibitor,viladazone(Vil),in various animal models of pain.METHODS ① Mouse acetic acid writhing test:KM mice were divided into the model group,model+morphine 10 mg·kg-1 group,and model+Vil 2,4,8 mg·kg-1 groups.Thirty minutes after ig administration of saline(model group)or corresponding drugs,each group was ip injected with a 2%acetic acid aqueous solution(0.01 mL·g-1),and the writhing frequency of the mice was observed and recorded from 5 to 20 min.② Mouse formalin pain test:KM mice were divided into the model group and model+Vil 2,4 and 8 mg·kg-1 groups.Thirty minutes after ig adminis-tration of saline(model group)or drugs,20 μL of 5%formalin solution was sc injected into the right plantar region of the mice.The licking time(the sum of the duration of licking and biting the paw)of the mice was observed and recorded during two periods:the acute phase(0-5 min after sc formalin injec-tion)and the delayed phase(15-35 min after sc formalin injection).③ Rat chronic constriction injury(CCI)of the sciatic nerve experiment:SD rats successfully examined with a paw withdrawal threshold(PWT)<5 g were randomly divided into a CCI model group and a CCI model+Vil 2,4 and 8 mg·kg-1 group.Solvent(model group)or corresponding drugs were ig administered,and the PWT of the modeled side was measured at 30,60,120 and 240 min after the first administration to evaluate the acute anal-gesic effect of Vil on mechanical pain.Then,Vil was continuously ig administered for 14 d,and the PWT was measured 1 h after Vil administration on the 7th and 14th d to evaluate the long-term analgesic effect of Vil.Immunofluorescence staining was employed to analyze the expression levels of inflamma-tion-related proteins,ionized calcium binding adapter molecule 1(IBA-1),tumor necrosis factor α(TNF-α),and interleukin 1β(IL-1β),in brain tissues.Enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of IBA-1,TNF-α and IL-1β in the dorsal root ganglion of the spinal cord in the CCI model.RESULTS ① In the mouse model of acetic acid writhing,single ig administration of morphine 10 mg·kg-1 and Vil at varied doses significantly reduced the number of writhings induced by acetic acid compared to the model group.② In the formalin-induced pain model,the average licking time of the model group was 50.5 s during the acute phase of inflammatory pain(0-5 min after intraplantar injec-tion of 5%formalin),and 347.9 s during the delayed phase of inflammatory pain(25-35 min after formalin injection).Compared to the model group,single ig administration of Vil 2-8 mg·kg-1 reduced chronic pain induced by formalin in mice,and each dose of Vil significantly decreased the licking time of mice,but had no notable impact on the licking duration exhibited by mice during acute phase.③ In the CCI model,the PWT values of CCI model rats significantly decreased compared with the control group.Pathological damage to varying extents was observed in brain slices,manifested as enlarged intercellular spaces and the appearance of vacuoles.The expression of IBA-1 in brain tissue significantly increased,while TNF-α and IL-1β hardly changed.The levels of IBA-1,TNF-α and IL-1β in the spinal dorsal root ganglion significantly increased.Compared with the CCI model,after single administration of Vil 2-8 mg·kg-1 for 60,120 and 240 min,Vil significantly reduced the PWT values.After two-week continuous administration,the PWT values in Vil 4 and 8 mg·kg-1 were significantly reduced,and Vil 2-8 mg·kg-1 could alleviate the neuropathic pain to some extent.Vil 8 mg·kg-1 significantly reduced the elevated levels of inflammatory factors compared to CCI rats.CONCLUSION The antidepressant Vil exhibits analgesic effects in mouse models of acetic acid writhing,formalin-induced inflammation,and neuropathic pain induced by CCI in rats,with a more pronounced effect on neuropathic pain.The mechanism of action may be related to the inhibition of inflammatory pathways of IBA-1.

Objective To investigate the risk factors for acute respiratory failure in immunocompromised patients with Pneumocystis jirovecii pneumonia(PJP).Methods Clinical data of 123 immunocompromised patients complicated with PJP hospitalized at Mengchao Hepatobiliary Hospital of Fujian Medical University from January 2021 to December 2023 were retrospectively collected and analyzed.SPSS 22.0 statistical software package was used to perform multivariate binary logistic regression analysis to identify risk factors for acute respiratory failure in PJP patients.Results Among the 123 PJP patients,77 were HIV-positive,and 46 were HIV-negative.HIV-negative PJP patients were more likely to have comorbidities such as hypertension(P＜0.001),diabetes mellitus(P＜0.001),coronary heart disease(P=0.034),chronic kidney disease(P＜0.001),chronic liver disease(P=0.019),chronic lung disease(P=0.011),and malignant tumor(P＜0.001).They were also more prone to respiratory failure(P＜0.001)and ICU admission(P＜0.001).The HIV-positive patients had significantly lower CD4+T lymphocyte counts and albumin levels(P＜0.001).Forty patients developed acute respiratory failure,and six patients died.Multivariate analysis showed that high neutrophil-to-lymphocyte ratio(NLR)(P=0.031),non-HIV infection(P=0.002),and concomitant infections with other pathogens(P＜0.001)were independent risk factors for incidence of respiratory failure.ROC curve analysis revealed that the area under the curve(AUC)was 0.686(0.584,0.789)for non-HIV infection,0.731(0.637,0.826)for concomitant infections with other pathogens,0.648(0.546,0.750)for NLR.The predicted probability was 0.845(0.778,0.912).Conclusions Non-HIV infection,high NLR,and concomitant infections with other pathogens are independent risk factors for incidence of respiratory failure in PJP patients.The panel combining these factors provides a higher predictive value for respiratory failure.Timely assessment of patient condition and early treatment are vital for better outcomes.

Objective:To investigate microstructural alterations in the optic chiasm and optic radiations of multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) based on diffusion kurtosis imaging (DKI).Methods:This study was a cross-sectional study. Retrospective analyses were conducted on the clinical and imaging data of 63 patients with relapsing-remitting MS (RRMS) and 62 patients with NMOSD diagnosed at First Affiliated Hospital of Chongqing Medical University from January 2019 to December 2023. According to the occurrence of optic neuritis (ON), they were categorized into ON-positive MS (ON+MS) group (40 cases), ON-negative MS (ON-MS) group (23 cases), ON-positive NMOSD (ON+NMOSD) group (40 cases) and ON-negative NMOSD (ON-NMOSD) group (22 cases). In addition, 40 healthy controls were enrolled during the same period. DKI data of all subjects were collected, and DKI post-processing was performed to obtain fractional anisotropy (FA), mean kurtosis (MK), axial kurtosis (AK), and radial kurtosis (RK) values of the optic chiasm and bilateral optic radiations. The scores of the mini-mental state examination (MMSE), montreal cognitive assessment (MoCA), and expanded disability status scale (EDSS) were obtained. The Kruskal-Wallis test was used to analyze the differences in DKI parameters of the optic chiasm and bilateral optic radiation among the 5 groups, and the Holm-Bonferroni method was employed for multiple comparison correction in pairwise comparisons.Results:There were statistically significant overall differences in the DKI parameters of the optic chiasm and bilateral optic radiations among healthy control group, ON+MS group, ON-MS group, ON+NMOSD group, and ON-NMOSD group (all P0.05). The FA value of the optic chiasm in ON+NMOSD group was significantly lower than that of healthy control group and ON-MS group, as well as ON-NMOSD group ( P0.05). The FA value of the left optic radiation in ON+NMOSD group was lower than that in healthy control group and the ON-MS group. The RK value of the optic chiasm in ON+MS group was lower than that in the healthy control group and ON-NMOSD group ( P0.05). The MK and RK values of the left optic radiation in ON-MS group were significantly lower than those in the ON+NMOSD group and ON-NMOSD group ( P0.05). Conclusions:NMOSD and RRMS patients demonstrate varying degrees of microstructural damage in the optic chiasm and optic radiations. Differences of DKI parameters suggest different pathological mechanisms of visual pathway damage between NMOSD and MS, which may be helpful for early detection of occult visual pathway lesions.

Objective:To investigate effect of Yiqi Huoxue Huazhuo Jiedu Prescription(YHHJP)on inflammatory factors of brain tissues,tight junction between brain and colon tissues,intestinal flora and bacterial metabolites in cerebral ischemia reperfusion injury(CIRI)rats based on brain-gut axis.Methods:Fifty male SD rats of SPF grade were randomly divided into sham-operation group(Sham),model group(MCAO),low,medium,high doses YHHJP groups(TCM-L/TCM-M/TCM-H).Middle cerebral artery occlusion model was established according to Zea Longa methods.Neurological function defects were detected 3 days after administra-tion.TTC staining was used to calculate infarct size of brain tissue.Pathological changes of brain tissue were observed by Nissl staining,and pathological changes of brain and colon tissues were observed by HE staining.IL-1β,IL-6,TNF-α in brain tissue and LPS con-tent in serum were detected by ELISA,and D-LA content in serum was detected by biochemical method.Gene expressions of ZO-1 and Claudin-5 in brain tissue and gene expressions of ZO-1,Claudin-1 in colon tissue were studied by Real-time fluorescent quantita-tive PCR.Intestinal flora were detected by 16S rDNA high-throughput sequencing.Results:Compared with Sham group,pathological damage of brain and colon tissue were serious in MCAO group,intestinal flora structure was significantly different,neural function im-pairment was aggravated,infarct size was increased,IL-1β,IL-6,TNF-α contents in brain tissue,and LPS,D-LA contents in serum were increased,gene expressions of ZO-1 and Claudin-5 in brain tissue and gene expressions of ZO-1 and Claudin-1 in colon tissue were decreased significantly(P<0.05).Compared with MCAO group,pathological damage of brain and colon tissue of rats were relieved in TCM-L,TCM-M,TCM-H groups,disturbance of intestinal microflora microecology was improved,neurological function impairment and infarct size were markedly decreased,IL-1β,IL-6,TNF-α contents in brain tissue were decreased,gene expressions of ZO-1 and Claudin-1 in colon tissue were increased significantly(P<0.05);LPS and D-LA contents in serum were decreased in YH-HJP medium and high doses groups,while gene expressions of ZO-1 and Claudin-5 in brain tissue were increased significantly(P<0.05).Conclusion:YHHJP has a good effect on improving CIRI,whose mechanism may be related to regulating diversity of intestinal flora,reducing release of intestinal bacterial metabolites LPS and D-LA,increasing gene expressions of tight junction proteins ZO-1,Claudin-5 and Claudin-1,and down-regulating secretion of proinflammatory cytokine.

ObjectiveTo observe the effect of Dahuang Xiezhuo prescription on the clinical symptoms， blood uric acid， and renal tubular function of patients with immunoglobulin A （IgA） nephropathy in stages 1-2 of chronic kidney disease （CKD） complicated with hyperuricemia （HUA）. MethodSixty patients with IgA nephropathy in stages 1-2 of CKD complicated with HUA of spleen and kidney deficiency and combined turbidity and blood stasis syndromes were randomly divided into an observation group and a control group， with 30 cases in each group. The patients in the control group received basic treatment， i.e.， losartan potassium tablets 50-100 mg/time， once per day， and sodium bicarbonate tablets 0.5 g/time， three times per day by oral administration， combined with low-salt， low-fat， and low-purine diet. The patients in the observation group received Dahuang Xiezhuo prescription on the basis of basic treatment， one dose per day， twice a day in the morning and evening with warm water. Both groups were treated for two months. The total scores of traditional Chinese medicine（TCM）syndrome， blood pressure， 24 h urinary protein （24 h UTP）， blood urea nitrogen （BUN）， serum creatinine （SCr） ［glomerular filtration rate （eGFR） was calculated by CKD-epidemiology collaboration （CKD-EPI） formula］， serum uric acid （SUA）， and renal tubular function indexes ［urinary α₁-microglobulin （α₁-MG）， urinary β₂-microglobulin （β₂-MG）， urinary kidney injury molecule-1 （KIM-1）， and neutrophil gelatinase-associated lipocalin （NGAL）］ of the two groups before treatment and two months after treatment were recorded. The clinical efficacy of the two groups was evaluated two months after treatment. ResultAfter 2 months of treatment，the total effective rate in the observation group was 81.48%（22/27），higher than 50.00%（14/28） in the control group（χ² =6.661，P<0.05）. The total scores of TCM syndrome， 24 h UTP， and SUA in the observation group and the observation group were lower than those before treatment （P<0.05）， and compared with the control group after treatment， the observation group decreased more significantly （P<0.05）. After treatment， the blood pressure in the observation group and the observation group was lower than that before treatment （P<0.05）， and there was no significant difference in blood pressure between the two groups after treatment. After treatment， the levels of urinary α₁-MG， β₂-MG， KIM-1， and NGAL in the two groups were lower than those before treatment （P<0.05）， and the observation group was lower than the control group after treatment （P<0.05）. There were no significant inter-group and intra-group differences in BUN， SCr， and eGFR levels before and after treatment. There were no obvious abnormalities in blood routine， liver function， and electrolytes before and after treatment in the two groups， and no adverse reactions such as allergies occurred. ConclusionDahuang Xiezhuo prescription can effectively improve the clinical symptoms of IgA nephropathy with HUA （CKD1-2） patients with spleen and kidney deficiency and combined turbidity and blood stasis syndromes， reduce blood uric acid level， alleviate renal tubular injury， and protect the kidney. The curative effect is better than that of basic treatment.

ObjectiveTo explore the mental health status and its influencing factors among middle school students in Xide County， Liangshan Yi Autonomous Prefecture， and to provide references for mental health interventions for local middle school students. MethodsUsing a cross-sectional study design， one junior middle school and one senior middle school in Xide County， Liangshan Prefecture， Sichuan Province， were randomly selected on September 16， 2021， and two classes per grade in each school involving 288 students were recruited. Subjects were assessed using Patients' Health Questionnaire Depression Scale-9 item （PHQ-9）， Generalized Anxiety Disorder Scale-7 item （GAD-7）， PTSD Checklist for DSM-5 （PCL-5）， Multidimensional Scale of Perceived Social Support （MSPSS） and UCLA Loneliness Scale （ULS-3）. Then the scores of above scales were compared among middle school students with different demographic characteristics， and binary Logistic regression analysis was conducted to screen the influencing factors of post-traumatic stress disorder (PTSD） symptoms. ResultsAmong the respondents， 17.71% （95% CI： 0.133~0.221）， 8.68% （95% CI： 0.054~0.120）， 2.78% （95% CI： 0.009~0.047） and 45.83% （95% CI： 0.400~0.516） were reported to have symptoms of depression， anxiety， PTSD and loneliness， respectively. Students in senior middle school scored lower on PCL-5 and ULS-3 than those in junior middle school ［（6.46±8.91） vs. （8.87±9.42）， t=2.202， P<0.05； （4.67±1.65） vs. （5.60±1.88）， t=4.431， P<0.01］. Regression analysis denoted that depressive symptoms （OR=7.630， P<0.05） and anxiety symptoms （OR=3.789， P<0.01） were risk factors for PTSD symptoms among middle school students. ConclusionThe middle school students in Xide County， Liangshan Yi Autonomous Prefecture suffer a high prevalence rate of depressive symptoms and loneliness， and those in junior middle school are more likely to feel a sense of strong loneliness， furthermore， depressive symptoms and anxiety symptoms are risk factors for PTSD symptoms.

Objective:To compare the head magnetic resonance imaging (MRI) changes and the distribution of pathogens of purulent meningitis in premature and full term infants.Methods:This retrospective study assessed clinical data in 43 cases of neonatal purulent meningitis with positive blood or cerebrospinal fluid bacterial culture admitted to the Neonatal Ward of Shengjing Hospital of China Medical University from January 2012 to November 2019.According to the gestational age, those patients were divided into the premature infant group and the full term infant group.The general situation, head MRI and pathogen characteristics of both groups were compared.Results:The incidence of premature rupture of fetal membranes in the premature infant group was higher than that in the full term infant group [50.00%(13/26 cases) vs.5.88%(1/17 cases)], the rate of cesarean section in the premature infant group was higher than that in the term infant group [61.54%(16/26 cases) vs.23.53%(4/17 cases)], and there were significant difference between the 2 groups ( χ2=9.011 and 5.969, respectively, all P<0.05). There was no significant difference between 2 groups in age of onset [(9.8±7.0) d vs.(8.9±5.5) d], diagnosis[(13.0±7.1) d vs.(10.2±6.1) d] and examination [(16.1±7.9) d vs.(13.1±6.5) d] (all P>0.05). The top 3 pathogens were Klebsiella pneumonia ( K. pneumoniae) in 14 cases, Escherichia coli ( E. coli) in 11 cases and Streptococcus agalactiae (GBS) in 7 cases. K. pneumoniae was the most common pathogen in premature infants, and GBS was the most common pathogen in term infants.In the first MRI, white matter injury (WMI) was the most common disease (19 cases), the abnormal rate of MRI in the premature infant group was 65.38% (17/26 cases), the incidence of intracranial hemorrhage in the premature infant group was higher than that in the term infant group, the abnormal rate of MRI in the term infant group was 52.94% (9/17 cases), and the incidence of cerebral infarction in the term infant group was higher than that in the premature infant group.The MRI positive rates of meningitis caused by K. pneumoniae, E. coli and GBS were 57.14% (8/14 cases), 72.73% (8/11 cases) and 71.43% (5/7 cases), respectively.Infants with K. pneumoniae infections suffered from the main complications of WMI and intracranial hemorrhage.Infants infected with E. coli were prone to WMI in the early stage and hydrocephalus in the late stage.Infants with GBS were prone to WMI and cerebral infarction in the early stage and cerebromalacia in the late stage. Conclusions:There were some differences in the distribution of pathogenic bacteria and head MRI changes between premature infants and term infants, and head MRI of purulent meningitis caused by different pathogenic bacteria.A thorough understanding of the distribution of pathogens and the characteristics of head MRI in premature and full term infants contributed to the early diagnosis, treatment and prognosis of this disease.