Intestinal bacterial overgrowth in the early stage of severe acute pancreatitis is associated with acute respiratory distress syndrome

BACKGROUND In the early stage of acute pancreatitis(AP),a large number of cytokines induced by local pancreatic inflammation seriously damage the intestinal barrier function,and intestinal bacteria and endotoxins enter the blood,causing inflammatory storm,resulting in multiple organ failure,infectious complications,and other disorders,eventually leading to death.Intestinal failure occurs early in the course of AP,accelerating its development.As an alternative method to detect small intestinal bacterial overgrowth,the hydrogen breath test is safe,noninvasive,and convenient,reflecting the number of intestinal bacteria in AP indirectly.This study aimed to investigate the changes in intestinal bacteria measured using the hydrogen breath test in the early stage of AP to clarify the relationship between intestinal bacteria and acute lung injury(ALI)/acute respiratory distress syndrome(ARDS).Early clinical intervention and maintenance of intestinal barrier function would be highly beneficial in controlling the development of severe acute pancreatitis(SAP).AIM To analyze the relationship between intestinal bacteria change and ALI/ARDS in the early stage of SAP.METHODS A total of 149 patients with AP admitted to the intensive care unit of the Digestive Department,Xuanwu Hospital,Capital Medical University from 2016 to 2019 were finally enrolled,following compliance with the inclusion and exclusion criteria.The results of the hydrogen breath test within 1 wk of admission were collected,and the hydrogen production rates at admission,72 h,and 96 h were calculated.The higher the hydrogen production rates the more bacteria in the small intestine.First,according to the improved Marshall scoring system in the 2012 Atlanta Consensus on New Standards for Classification of Acute Pancreatitis,66 patients with a PaO2/FiO2 score≤1 were included in the mild AP(MAP)group,18 patients with a PaO2/FiO2 score≥2 and duration<48 h were included in the moderately SAP(MSAP)group,and 65 patients with a PaO2/FiO2 score≥2 and duration>48 h were included in the SAP group,to analyze the correlation between intestinal bacterial overgrowth and organ failure in AP.Second,ALI(PaO2/FiO2=2)and ARDS(PaO2/FiO2>2)were defined according to the simplified diagnostic criteria proposed by the 1994 European Union Conference.The MSAP group was divided into two groups according to the PaO2/FiO2 score:15 patients with PaO2/FiO2 score=2 were included in group A,and three patients with score>2 were included in group B.Similarly,the SAP group was divided into two groups:28 patients with score=2 were included in group C,and 37 patients with score>2 were included in group D,to analyze the correlation between intestinal bacterial overgrowth and ALI/ARDS in AP.RESULTS A total of 149 patients were included:66 patients in the MAP group,of whom 53 patients were male(80.3%)and 13 patients were female(19.7%);18 patients in the MSAP group,of whom 13 patients were male(72.2%)and 5 patients were female(27.8%);65 patients in the SAP group,of whom 48 patients were male(73.8%)and 17 patients were female(26.2%).There was no significant difference in interleukin-6 and procalcitonin among the MAP,MSAP,and SAP groups(P=0.445 and P=0.399,respectively).There was no significant difference in the growth of intestinal bacteria among the MAP,MSAP,and SAP groups(P=0.649).There was no significant difference in the growth of small intestinal bacteria between group A and group B(P=0.353).There was a significant difference in the growth of small intestinal bacteria between group C and group D(P=0.038).CONCLUSION Intestinal bacterial overgrowth in the early stage of SAP is correlated with ARDS.

Association between acute pancreatitis and small intestinal bacterial overgrowth assessed by hydrogen breath test

AIM To elucidate the effects of small intestinal bacterial overgrowth(SIBO) on the severity and complications of acute pancreatitis(AP).METHODS In total,208 patients with AP as defined by the revised Atlanta classification were admitted to Xuanwu Hospital of capital Medical University from 2013 to 2016. All patients were admitted within 72 h of AP onset. The hydrogen breath test was performed 7 d after AP onset to detect hydrogen production and evaluate the development of SIBO. The incidence of SIBO was analyzed in patients with AP of three different severity grades. The association between SIBO and complications of AP was also assessed.RESULTS Of the 27 patients with severe AP(SAP),seven(25.92%) developed SIBO. Of the 86 patients with moderately severe AP(MSAP),22(25.58%) developed SIBO. Of the 95 patients with mild AP(MAP),eight(8.42%) developed SIBO. There were significant differences in the rates of SIBO among patients with AP of different severities. Additionally,more severe APwas associated with higher rates of SIBO positivity(P < 0.05). SIBO in patients with AP mainly occurred within 72 h of the onset of AP. The incidence of organ failure was significantly higher in patients with SIBO than in those without(P < 0.05).CONCLUSION SIBO occurs more frequently in patients with MSAP or SAP than in those with MAP,usually ≤ 72 h after AP onset. Additionally,SIBO is associated with organ failure.

Development of a novel score for the diagnosis of bacterial infection in patients with acute-on-chronic liver failure

BACKGROUND The diagnosis of bacterial infection is difficult in patients with acute-on-chronic liver failure(ACLF).AIM To evaluate the diagnostic accuracy of widely used parameters for bacterial infection in ACLF and to develop a simple scoring system to improve diagnostic efficiency.METHODS This was a retrospective study.Procalcitonin(PCT),white blood cells(WBC),proportion of neutrophils(N%),and C-reactive protein(CRP)were examined.Logistic regression was used to select variables for the scoring models and receiver operating characteristic curve(ROC)analysis was used to evaluate the diagnostic value of different indices.RESULTS This study included 386 patients with ACLF,169(43.78%)of whom had bacterial infection on admission.The area under the ROC(AUROC)of PCT,CRP,WBC and N%for the diagnosis of bacterial infection ranged from 0.637 to 0.692,with no significant difference between them.Logistic regression showed that only N%,PCT,and CRP could independently predict infection.A novel scoring system(infection score)comprised of N%,PCT and CRP was developed.The AUROC of the infection score was 0.740,which was significantly higher than that for the other four indices(infection score vs N%,PCT,CRP,and WBC,P=0.0056,0.0001,0.0483 and 0.0008,respectively).The best cutoff point for the infection score was 4 points,with a sensitivity of 78.05%,a specificity of 55.29%,a positive predictive value of 57.91%and a negative predictive value of 76.16%.CONCLUSION The infection score is a simple and useful tool for discriminating bacterial infection in ACLF.

Clinical characteristics and 28-d outcomes of bacterial infections in patients with hepatitis B virus-related acute-on-chronic liver failure

BACKGROUND Acute-on-chronic liver failure (ACLF),which includes hepatic and multiple extrahepatic organ failure,is a severe emergency condition that has high mortality.ACLF can rapidly progress and requires an urgent assessment of condition and referral for liver transplantation.Bacterial infections (BIs) trigger ACLF and play pivotal roles in the deterioration of clinical course.AIM To investigate the clinical characteristics and 28-d outcomes of first Bis either at admission or during hospitalization in patients with hepatitis B virus (HBV)-ACLF as defined by the Chinese Group on the Study of Severe Hepatitis B(COSSH).METHODS A total of 159 patients with HBV-ACLF and 40 patients with acute decompensation of HBV-related chronic liver disease combined with first BIs were selected for a retrospective analysis between October 2014 and March 2016 The characteristics of BIs,the 28-d transplant-free survival rates,and the independent predictors of the 28-d outcomes were evaluated.RESULTS A total of 194 episodes of BIs occurred in 159 patients with HBV-ACLF.Among the episodes,13.4 To were community-acquired,46.4 To were healthcare-associated,and 40.2% belonged to nosocomial BIs.Pneumonia (40.7%),spontaneous bacterial peritonitis (SBP)(34.5%),and bloodstream infection (BSI)(13.4%) were the most prevalent.As the ACLF grade increased,the incidence of SBP showed a downward trend (P=0.021).Sixty-one strains of bacteria,including 83.6% Gramnegative bacteria and 29.5% multidrug-resistant organisms,were cultivated from 50 patients with ACLF.Escherichia coli (44.3%) and Klebsiella pneumoniae (23.0%)were the most common bacteria.As the ACLF grade increased,the 28-d transplant-free survival rates showed a downward trend (ACLF-1,55.7%;ACLF-2,29.3%;ACLF-3,5.4%;P <0.001).The independent predictors of the 28-doutcomes of patients with HBV-ACLF were COSSH-ACLF score (hazard ratio[HR]=1.371),acute kidney injury (HR=2.187),BSI (HR=2.339),prothrombin activity (HR=0.967),and invasive catheterization (HR=2.173).CONCLUSION For patients with HBV-ACLF combined with first BIs,pneumonia is the most common form,and the incidence of SBP decreases with increasing ACLF grade.COSSH-ACLF score,acute kidney injury,BSI,prothrombin activity,and invasive catheterization are the independent predictors of 28-d outcomes.

Diagnostic accuracy of C-reactive protein for bacterial infections in acute exacerbation of chronic obstructive pulmonary disease: A meta-analysis

Objective:The clinical diagnostic accuracy of C-reactive protein(CRP)for bacterial infections in acute exacerbation of chronic obstructive pulmonary disease(AECOPD)is still controversial.This study evaluated its accuracy through Meta-analysis.Methods:Studies on the diagnostic value of CRP for bacterial infections in AECOPD were searched form Web of Science,PubMed,Cochrane library,EMBASE,WANFANG DATA,CNKI and China Biology Medicine disc.The included studies were evaluated according to QUADAS-2 assessment tool.Stata 12.0 software was used for meta analyses to summarize the sensitivity and the specificity of the included studies,and the heterogeneity test was conducted.The symmetric receiver operating characteristic curves(SROC)was drawn and the area under the curve(AUC)was calculated,and the funnel plot was drawn to determine publication bias.Results:664 studies were initially identified,20 of which met the inclusion criteria(9 in English and 11 in Chinese).Meta-analysis results showed that the summary sensitivity and specificity of CRP in diagnosing bacterial infections in AECOPD were 0.84,95%CI(0.77-0.90)and 0.76,95%CI(0.67-0.82),respectively.The AUC of SROC was 0.87,95%CI(0.83-0.89).Conclusion:CRP has high accuracy,sensitivity and specificity in distinguishing AECOPD bacterial infections from non-bacterial infection.

Formulation of an Early Warning Infectivity Score System for Adult Patients with Acute Bacterial Diarrhea

The aim of our study was to develop a scoring system to predict whether diarrhea is of a bacterial origin and whether the diarrheal patients constitute a potential source of infection to others. Adults with acute diarrhea （n=424） were enrolled in the study. Logistic regression and standard regression coefficients were used to formulate the Early Warning Infectivity Score System for Adults with Acute Bacterial Diarrhea （EWIS-ABD）. Four risk factors were identified by logistic regression, including body temperature （P〈0.01）, abdominal pain （P〈0.01）, leukocyte count in stool （P〈0.01）, and unclean dietary history （P〈0.01）. EWIS-ABD was thus developed, in which the value 〉5 points was set as an indicator of bacterial diarrhea. The incidence of bacterial diarrhea increased along with the elevated score. EWIS-ABD was more specific for bacterial diarrhea than for viral diarrhea. The accuracy and reliability of EWIS-ABD was high by prospective validation in 478 patients with acute diarrhea.

Selective intestinal decontamination for the prevention of early bacterial infections after liver transplantation

Bacterial infection in the first month after liver transplantation is a frequent complication that poses a serious risk for liver transplant recipients as contributes substantially to increased length of hospitalization and hospital costs being a leading cause of death in this period. Most of these infections are caused by gramnegative bacilli, although gram-positive infections, especially Enterococcus sp. constitute an emerging infectious problem. This high rate of early postoperative infections after liver transplant has generated interest in exploring various prophylactic approaches to surmount this problem. One of these approaches is selective intestinal decontamination(SID). SID is a prophylactic strategy that consists of the administration of antimicrobials with limited anaerobicidal activity in order to reduce the burden of aerobic gram-negative bacteria and/or yeast in the intestinal tract and so prevent infections caused by these organisms. The majority of studies carried out to date have found SID to be effective in the reduction of gram-negative infection, but the effect on overall infection is limited due to a higher number of infection episodes by pathogenic enterococci and coagulase-negative staphylococci. However, difficulties in general extrapolation of the favorable results obtained in specific studies together with the potential risk of selection of multirresistant microorganisms has conditioned controversy about the routinely application of these strategies in liver transplant recipients.

Acute suppurative terminal cholangitis:Clinical characteristics of a new subtype of acute cholangitis

Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Methods:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August 2020.We analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and prognosis.Results:A total of 32 ASTC patients were included in the analysis.The majority of the patients had a history of biliary operations,and clinical manifestations were occult and atypical.The positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance imaging.Treatment with effective antibiotics was provided as soon as diagnosis was established.After treatment,most patients had a good outcome.Elevated levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor prognosis.Conclusions:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.

Helicobacter pylori infection and small intestinal bacterial overgrowth–more than what meets the eye

Helicobacter pylori(H.pylori)infection is very common and affects a significant proportion of the world population.In contrast,the prevalence of small intestinal bacterial overgrowth(SIBO)in the general population is not well understood.There can be coexistence of both disease states in a given patient and their clinical symptoms may also overlap with one and another.There is no clear clinical guidelines for testing for and treating SIBO in patients with H.pylori infection.This review article explores the available evidence on the relationship between H.pylori infection and SIBO,diagnosis and treatment of these entities and also comments on associated non-gastrointestinal conditions.

Studying host genetic background effects on multimorbidity of intestinal cancer development,type 2 diabetes and obesity in response to oral bacterial infection and high-fat diet using the collaborative cross(CC)lines

Background:Multimorbidity of intestinal cancer(IC),type 2 diabetes(T2D)and obesity is a complex set of diseases,affected by environmental and genetic risk factors.High-fat diet(HFD)and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.Methods:To study the complexity of this multimorbidity,we used the collaborative cross(CC)mouse genetics reference population.We aimed to study the multimorbidity of IC,T2D,and obesity using CC lines,measuring their responses to HFD and oral bacterial infection.The study used 63 mice of both sexes generated from two CC lines(IL557 and IL711).For 12 weeks,experimental mice were maintained on specific dietary regimes combined with co-infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum,while control groups were not infected.Body weight(BW)and results of a intraperitoneal glucose tolerance test(IPGTT)were recorded at the end of 12 weeks,after which length and size of the intestines were assessed for polyp counts.Results:Polyp counts ranged between 2 and 10 per CC line.The combination of HFD and infection significantly reduced(P<.01)the colon polyp size of IL557 females to 2.5 cm 2,compared to the other groups.Comparing BW gain,IL557 males on HFD gained 18 g,while the females gained 10 g under the same conditions and showed the highest area under curve(AUC)values of 40000-45000(min mg/dL)in the IPGTT.Conclusion:The results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance,and this effect is gender related.

Bacterial infection triggers and complicates acute-on-chronic liver failure in patients with hepatitis B virus-decompensated cirrhosis: A retrospective cohort study

BACKGROUND Reports on bacterial infection(BI)in decompensated cirrhosis(DC)is mainly from alcoholic cirrhosis.The role of BI as a trigger or complication of acute-onchronic liver failure(ACLF)in patients with hepatitis B virus decompensated cirrhosis(HBV-DC)remains to be investigated.AIM To investigate the impact of BI on the outcomes of the patients with HBV-DC admitted into the hospital with or without ACLF.METHODS This retrospective study included patients with HBV-DC admitted to two tertiary centers in China.In-hospital overall survival,90-d transplant-free survival,5-year post-discharge survival,and cumulative incidence of ACLF were evaluated.Risk factors for death were analyzed considering liver transplantation as a competing event.RESULTS A total of 1281 hospitalized HBV-DC patients were included;284 had ACLF at admission.The overall prevalence of BI was 28.1%.The patients with BI had a significantly lower in-hospital survival and transplant-free 90-d survival than those without,in both the patients admitted with and without ACLF.The presence of BI significantly increased the risk of developing ACLF[subdistribution hazard ratio(sHR)=2.52,95%CI:1.75-3.61,P<0.001]in the patients without ACLF.In the patients discharged alive,those who had an episode of BI had a significantly lower 5-year transplant-free survival.BI was an independent risk factor for death in the patients admitted without ACLF(sHR=3.28,95%CI:1.93-5.57),while in ACLF admissions,the presence of pneumonia,but not other type of BI,independently increased the risk of death(sHR=1.87,95%CI:1.24-2.82).CONCLUSION BI triggers ACLF in patients with HBV-DC and significantly impairs short-term survival.HBV-DC patients should be monitored carefully for the development of BI,especially pneumonia,to avoid an adverse outcome.

Influence of Intestinal Lymphatic Ligation on Pulmonary Injury in Rats with Severe Acute Pancreatitis

Objective:The present study explored the mechanisms involved in intestinal lymphatic ligation in rats with severe acute pancreatitis(SAP).Methods:Male Sprague Dawley rats were randomly divided into 4 groups:saline group,saline+ligation group,SAP group,and SAP+ligation group.Rats in the SAP group were administered sodium taurocholate solution.Isolated mesenteric lymph duct ligation was administered to the saline+ligation and SAP+ligation groups.Endotoxin(ET),nitric oxide(NO),tumor necrosis factor-α(TNF-α),interleukin-1(IL-1),myeloperoxidase(MPO),and superoxide dismutase(SOD)were detected.Nuclear factor-KB(NF-κB)and intercellular cell adhesion molecule-1(ICAM-1)proteins were observed.The mRNA of inducible nitric oxide synthase(iNOS)and Toll-like receptor 4(TLR4)was detected by PCR.Results:Pathomorphological analysis showed that necrosis was present in the lung of rats in the SAP group,but only mild lesions in the SAP+ligation group.ET,NO,TNF-α,and IL-1 in the serum and lung tissue were significantly decreased and MPO was increased in the SAP+ligation group as compared with the SAP group.However,MPO was increased.The expression of NF-κB and ICAM-1,either iNOS or TLR4,was upregulated in the SAP group,but downregulated in the SAP+ligation group.Intestinal lymph duct ligation prevented ET translocation,the release of inflammation factors,and inflammation injury.Conclusion:The intestinal lymph duct ligation could alleviate SAP-induced pulmonary injury by suppressing NF-κB activation in rats.

Influence of splanchnic vascular infusion on the content of endotoxins in plasma and the translocation of intestinal bacteria in rats with acute hemorrhage necrosis pancreatitis

The main reason for the death of the patient with acute hemorrhage necrosis pancreatitis (AHNP) is pancreatic infection and multi-organ failure caused by endotoxemia and intestinal bacterial translocation[1-7]. However, the pathogenesis of endotoxemia and intestinal bacterial translocation remains a question[8-10]; moreover, no effective method of prevention and cure for it has been found till now[11 -15] In the present study, we infused low dose dopamine and low molecular weight dextran through the catheters to abdominal aorta and portal vein, and observed its influence on the endotoxin concentration in plasma and the rate of translocation of intestinal bacteria in AHNP rats.

Quantitative analysis of intestinal gas in patients with acute pancreatitis

BACKGROUND: Disturbance of gastrointestinal function is a common complication in the early phase of acute pancreatitis (AP). Intestinal gas may reflect the function of the gut. Using plain abdominal radiographs, we investigated whether intestinal gas volume is related to AP. METHODS: Plain abdominal radiographs of 68 patients with AP within 24 hours after admission and 21 normal controls were digitized and transmitted to a computer. The region of intestinal gas was identified by an image manipulation software and the gas volume score (GVS) was calculated. The relationships between the GVS values and various clinical factors of AP were analyzed. RESULTS: The GVS in the AP group was 0.084±0.016, in the mild AP (MAP) group 0.070±0.005, and in the severe AP (SAP) group 0.094±0.013; all values were higher than that in the control group (P<0.01). The GVS in the SAP group was higher than that in the MAP group. The GVSs were correlated to the Ranson’s scores (r=0.762, P<0.01) and the acute physiology and chronic health evaluation II (APACHE II) scores (r=0.801, P<0.01). In addition, the GVS in patients with secondary pancreatic and/or peripancreatic infection was 0.107±0.014, higher than that in patients without secondary infection (P<0.01). GVS was not related to gender, age, etiology or clinical outcome of AP. CONCLUSIONS: Intestinal gas volume is significantly elevated in patients with AP. It is closely related to Ranson’s and APACHE II score and secondary pancreatic and/or peripancreatic infection. GVS may be a new prognostic tool for assessing the severity of AP in the early course of the disease.

Secondary Bacterial Organizing Pneumonia in a Patient Recovered from COVID-19 Disease: A Case Report

COVID-19 disease is a global pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) that mainly presents with pneumonia, but has variable multi-systemic manifestations. Concomitant bacterial infections associated with the acute stage of COVID-19 disease have been rarely reported in the literature. However, to our knowledge, post viral organizing pneumonia (OP) secondary to bacterial infection after recovery from SARS-CoV2 infection has not been noted before. We report a 27-year-old male patient with Type 1 Diabetes Mellitus who presented with fever post recovery from COVID-19 disease for seven weeks and was found to have OP secondary to Klebsiella pneumoniae. Furthermore, the bronchoalveolar lavage was positive for SARS-CoV2 by RT-PCR despite multiple negative nasopharyngeal RT-PCR. The patient was successfully treated with antibiotics only. Therefore, we conclude that early recognition of OP secondary to bacterial infection in patients with COVID-19 disease and prompt antibiotic treatment could avoid the use of a prolonged course of steroids.

Incidence of infectious complications is associated with a high mortality in patients with hepatitis B virus-related acute-on-chronic liver failure

BACKGROUND In China,hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is the most common liver failure characterized by serious clinical syndromes of liver decompensation with a very high mortality.Bacterial and/or fungal infections are the most common complications that are associated with high short-term mortality.Bacterial translocation from the intestine,impaired hepatic clearance,and immune paralysis of circulating immune cells are thought to contribute to infectious complications in liver failure.The control of bacterial and fungal infections is the key to improving HBV-ACLF outcomes.Active prevention,early diagnosis,and timely treatment of bacterial and fungal infections are essential for treating HBV-ACLF.AIM To investigate the frequency and role of bacterial and fungal infections in patients with HBV-ACLF.METHODS Patients with HBV-ACLF hospitalized at Taihe Hospital,Hubei University of Medicine from January 2014 to December 2017 were retrospectively enrolled.Patient-related information was retrieved from the hospital case database,including general information,blood biochemistry,complications,etc.According to the occurrence of secondary infection or not,the patients were divided into an infection group and a non-infection group.The sites,types,and incidences of bacterial and fungal infections and the influence of infections on the prognosis of HBV-ACLF were statistically analyzed.The risk factors for infections were assessed by unconditional logistic regression.RESULTS There were 174 cases of HBV-ACLF that met the enrollment criteria,of which 114 (65.52%) were diagnosed with infectious complications.Infections occurred in the abdominal cavity (87 cases),respiratory tract (51 cases),urinary tract (18 cases),and biliary tract (10 cases).Patients with infectious complications had a significantly higher 28-d mortality (70.18%,80/114) than those without (40.00%,24/60)(70.18% vs 40.00%,P < 0.05).And patients with infectious complications had a much higher incidence of non-infectious complications (54.39%,62/114)(54.39% vs 15.00%,P < 0.05),leading to an extremely high 28-d mortality of 88.71%(55/62)(P < 0.05).The grade of liver failure,period of hospital stay ≥ 30 d,age ≥ 45 years,and percentage of neutrophils > 70% were identified as risk factors for infectious complications.CONCLUSION The high incidence of infectious complications in patients with HBV-ACLF is associated with severity and deterioration of the disease and may contribute to the extremely high mortality of these patients.

Bacterial colonization and intestinal mucosal barrier development

The intestinal tract is colonized soon after birth with a variety of ingested environmental and maternal microflora. This process is influenced by many factors including mode of delivery, diet, environment, and the use of antibiotics. Normal intestinal microflora provides protection against infection, ensures tolerance to foods, and contributes to nutrient digestion and energy harvest. In addition, enteral feeding and colonization with the normal commensal flora are necessary for the maintenance of intestinal barrier function and play a vital role in the regulation of intestinal barrier function. Intestinal commensal microorganisms also provide signals that foster normal immune system development and influence the ensuing immune responses. There is increasingly recognition that alterations of the microbial gut flora and associated changes in intestinal barrier function may be related to certain diseases of the gastrointestinal tract. This review summarizes recent advances in understanding the complex ecosystem of intestinal microbiota and its role in regulating intestinal barrier function and a few common pediatric diseases. Disruption in the establishment of a stable normal gut microflora may contribute to the pathogenesis of diseases including inflammatory bowel disease, nosocomial infection, and neonatal necrotizing enterocolitis.

急性髓系白血病合并血流感染的病原菌分布与耐药性变迁及患者死亡的危险因素分析

目的探讨成人急性髓系白血病(AML)合并血流感染的病原菌分布与耐药性变迁,并分析患者死亡的危险因素。方法比较85例AML合并血流感染确诊时间的前30个月(2017年1月—2019年6月检出的病原菌)和后30个月(2019年7月—2021年12月)的病原菌检出率和主要病原菌耐药率变迁情况。并按患者血流感染后6个月预后分为死亡组33例和生存组52例。采用Logistic回归分析影响AML合并血流感染患者死亡的危险因素。结果85例AML合并血流感染患者共检出98株病原菌,以革兰阴性菌为主(65/98,66.33%),其次为革兰阳性菌(29/98,29.59%)、真菌(4/98,4.08%)。后30个月检出真菌(均为念珠菌)比例较前30个月增多(P<0.05)。后30个月与前30个月检出革兰阴性菌、革兰阳性菌比例及大肠埃希菌、金黄色葡萄球菌耐药率比较差异均无统计学意义(P>0.05)。Logistic回归分析显示,确诊前1个月内抗生素使用史、感染性休克为AML合并血流感染患者死亡的独立危险因素(P<0.05)。结论成人AML合并血流感染的病原菌以革兰阴性菌为主,但近年念珠菌感染率升高,且血流感染前使用抗生素及并发感染性休克者易出现预后不良。

慢加急性乙型肝炎肝衰竭患者细菌感染病原菌分布及血清PCT、IFN-γ和IL-6水平变化分析

目的调查慢加急性乙型肝炎肝衰竭(HBV-ACLF)患者细菌感染病原菌分布特征,分析血清降钙素原(PCT)、干扰素-γ(IFN-γ)和白细胞介素-6(IL-6)水平预测细菌感染的效能。方法2019年12月~2023年1月我院收治的HBV-ACLF患者86例,常规分离和鉴定菌种,采用电化学发光免疫法检测血清PCT水平,采用ELISA法检测血清IFN-γ和IL-6水平,应用受试者工作特征(ROC)曲线评估血清指标联合预测HBV-ACLF患者发生细菌感染的效能。结果本组发生细菌感染者37例,未发生明确感染者49例;在37例HBV-ACLF并发细菌感染患者中,共检出68株感染病原菌,其中革兰氏阴性菌41株(60.3%),革兰氏阳性菌27株(39.7%);感染组血清PCT、IFN-γ和IL-6水平分别为(10.9±3.1)μg/L、(46.5±1.9)pg/mL和(16.9±1.6)pg/mL,均显著高于未感染组【分别为(0.9±0.1)μg/L、(20.1±2.4)pg/mL和(4.8±0.9)pg/mL,P<0.05】,28 d和90 d病死率分别为67.6%和75.7%,均显著高于未感染组(分别为8.2%和12.2%,P<0.05);经ROC分析显示,分别以PCT>3.3μg/L、IFN-γ>45.5 pg/mL和IL-6>15.4pg/mL为截断点,其联合预测HBV-ACLF患者并发细菌感染的曲线下面积(AUC)为0.874,诊断的灵敏度为93.6%,特异度为84.1%。结论HBV-ACLF患者细菌感染的病原菌分布具有一定的特征性,以革兰氏阴性菌感染为主,除检测血清PCT水平外,监测血清IFN-γ和IL-6水平可能有助于早期发现细菌感染而给予预防性处理,或能提供生存率。

血清LBP、CXCL-10对小儿急性上呼吸道细菌感染的鉴别诊断价值及其影响因素

目的探讨血清脂多糖结合蛋白(LBP)、血清CXC趋化因子配体-10(CXCL-10)对小儿急性上呼吸道细菌感染的鉴别诊断价值及其影响因素。方法将2021年7月至2022年6月该院收治的90例急性上呼吸道感染患儿纳入研究作为研究组。另选取同期于本院进行体检40例健康儿童作为健康组。根据痰液细菌培养结果将研究组患儿分为细菌感染组(51例)和非细菌感染组(39例)。采用酶联免疫吸附法检测血清LBP、CXCL-10水平。采用受试者工作特征(ROC)曲线评估血清LBP、CXCL-10对小儿急性上呼吸道细菌感染的鉴别诊断价值。采用多因素Logistic回归分析小儿急性上呼吸道细菌感染的影响因素。结果研究组血清LBP、CXCL-10水平高于健康组(P<0.05)。细菌感染组血清LBP、CXCL-10水平高于非细菌感染组(P<0.05)。血清LBP、CXCL-10单独及联合用于诊断小儿急性上呼吸道细菌感染的曲线下面积(AUC)分别为0.779(95%CI:0.724~0.822)、0.843(95%CI:0.796~0.898)、0.906(95%CI:0.852~0.959)。细菌感染组家庭成员吸烟、铁元素缺乏、钙元素缺乏者所占比例、年均抗菌药使用次数、血清LBP、CXCL-10水平均高于非细菌感染患者(P<0.05)。Logistic多因素回归分析显示,年均抗菌药使用次数≥2次(OR=2.305,95%CI:1.483~3.582)、LBP≥104.26 ng/mL(OR=2.573,95%CI:1.446~4.578)、CXCL-10≥112.98 pg/mL(OR=1.208,95%CI:0.110~1.314)是小儿急性上呼吸道细菌感染的影响因素(P<0.05)。结论血清LBP、CXCL-10水平升高与儿童急性上呼吸道细菌感染密切相关,可作为鉴别诊断急性上呼吸道细菌感染的指标且二者联合诊断的效能更高。