Objective: To investigate the clinical characteristics, serogroups and antimicrobial resistance of invasive non-typhoid Salmonella infection in children at Xiamen. Methods: Retrospective cohort study. The clinical manifestations, treatment, prognosis, serogroups and antimicrobial resistance of 29 hospitalized children with invasive non-typhoid Salmonella infection confirmed by blood, cerebrospinal fluid, bone marrow and other sterile body fluids or deep pus culture at the Department of Infectious Diseases, the Department of Orthopedics and the Department of General Surgery in Xiamen Children's Hospital from January 2016 to December 2021 were analyzed. According to the clinical diagnosis criteria, the patients were divided into sepsis group and non-sepsis group (bacteremia and local suppurative infection). The inflammatory markers, serogroups distribution and drug resistance were compared between the two groups. Comparison between groups using Mann-Whitney U test and χ² test. Results: Among the 29 cases, there were 17 males and 12 females, with an onset age of 14 (9, 25) months, and 10 cases (34%) of patients were younger than 1 year old, 15 cases (52%) under 1 to 3 years old, and 4 cases (14%) greater than or equal 3 years old. The onset time of 25 cases (86%) was from April to September. The diseases included 19 cases (66%) septicemia (2 of which were combined with suppurative meningitis), 10 cases (34%) non-sepsis group, including 7 cases bacteremia and 3 cases local suppurative infection (2 cases of osteomyelitis, 1 case of appendicitis with peritonitis). The clinical manifestations were fever in 29 cases (100%), diarrhea and abdominal pain in 18 cases (62%), cough and runny nose in 10 cases (34%). Eighteen cases (62%) were cured and 11 cases (38%) were improved by effective antibiotics treatment. C-reactive protein in sepsis group was significantly higher than that in non-sepsis group (25.2 (16.1, 56.4) vs. 3.4 (0.5, 7.5) mg/L, Z=-3.81, P<0.001).The serogroups of C, B and E were the most prevalent among non-typhoid Salmonella isolates, accounting for 10 cases (34%), 9 cases (31%) and 7 cases (24%) respectively. Antibacterial drug sensitivity test showed that the sensitivity rates of imipenem, ertapenem and piperaciratazobactam were all 100% (31/31), those of ceftazidime, ceftriaxone, and cefepime were 94% (29/31), 94% (29/31) and 97% (30/31) respectively. The drug resistance rates of ampicillin, ampicillin-sulbactam and trimethoprim-sulfamethoxazole were 51% (16/31), 48% (15/31) and 48% (15/31) respectively, those of cefazolin, cefotetan, tobramycin, gentamicin and amikacinwere all 100% (31/31). There were no significant differences in the drug resistance rates of ceftazidime, ceftriaxone, aztreonam, ampicillin-sulbactam, ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin between the sepsis group and the non-sepsis group (χ²=0.31,0.31,0.00,0.02,0.02,0.02,0.26, all P>0.05). Conclusions: Invasive non-typhoid Salmonella infection in children at Xiamen mainly occurred in infants younger than 3 years old.The main clinical manifestations are fever, abdominal pain and diarrhea. C-reactive protein can be served as the laboratory indicators for indicating sepsis. The third generation of cephalosporins is recommended as the first choice for treatment.
Infant ; Male ; Female ; Child ; Humans ; Child, Preschool ; Anti-Bacterial Agents/therapeutic use* ; Ceftriaxone/therapeutic use* ; Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use* ; Ceftazidime/therapeutic use* ; Retrospective Studies ; C-Reactive Protein ; Drug Resistance, Bacterial ; Salmonella Infections/microbiology* ; Ampicillin/therapeutic use* ; Salmonella ; Diarrhea/drug therapy* ; Bacteremia ; Abdominal Pain ; Microbial Sensitivity Tests

Humans ; Escherichia coli ; Klebsiella pneumoniae ; Retrospective Studies ; Hospitals, General ; Singapore/epidemiology* ; Escherichia coli Infections/epidemiology* ; Sepsis/drug therapy* ; beta-Lactamases ; Anti-Bacterial Agents/therapeutic use* ; Bacteremia/drug therapy* ; Microbial Sensitivity Tests

Objective: To assess the efficacy and safety of polymyxin B in neutropenic patients with hematologic disorders who had refractory gram-negative bacterial bloodstream infection. Methods: From August 2021 to July 2022, we retrospectively analyzed neutropenic patients with refractory gram-negative bacterial bloodstream infection who were treated with polymyxin B in the Department of Hematology of the First Affiliated Hospital of the Soochow University between August 2021 to July 2022. The cumulative response rate was then computed. Results: The study included 27 neutropenic patients with refractory gram-negative bacterial bloodstream infections. Polymyxin B therapy was effective in 22 of 27 patients. The median time between the onset of fever and the delivery of polymyxin B was 3 days [interquartile range (IQR) : 2-5]. The median duration of polymyxin B treatment was 7 days (IQR: 5-11). Polymyxin B therapy had a median antipyretic time of 37 h (IQR: 32-70). The incidence of acute renal dysfunction was 14.8% (four out of 27 cases), all classified as "injury" according to RIFLE criteria. The incidence of hyperpigmentation was 59.3%. Conclusion: Polymyxin B is a viable treatment option for granulocytopenia patients with refractory gram-negative bacterial bloodstream infections.
Humans ; Polymyxin B/adverse effects* ; Retrospective Studies ; Gram-Negative Bacterial Infections/complications* ; Fever/drug therapy* ; Sepsis/drug therapy* ; Anti-Bacterial Agents/therapeutic use* ; Bacteremia/complications*

OBJECTIVES: To study the changes in the distribution and drug resistance profiles of pathogens causing bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia. METHODS: The medical data were collected from the children with acute lymphoblastic leukemia who were admitted to the First Affiliated Hospital of Zhengzhou University between January 2015 and December 2020 and developed bloodstream infection after chemotherapy. The samples were divided into the first three years group and the next three years group according to the time of testing to investigate the differences in the distribution and drug resistance profiles of pathogens as time. RESULTS: A total of 235 strains of pathogens were isolated, among which there were 159 Gram-negative strains (67.7%; mainly Escherichia coli and Klebsiella pneumoniae), 61 Gram-positive strains (26.0%; mainly Staphylococcus epidermidis), and 15 strains of fungi (6.4%; mainly Candida albicans). There were no significant differences between the first three years group and the next three years group in the detection rate of Gram-negative bacteria (68.8% vs 66.9%, P>0.05) or Gram-positive bacteria (29.2% vs 23.7%, P>0.05). Compared with the first three years group, the next three years group had significant increases in the detection rate of Streptococcus mitis (5.8% vs 0.0%, P<0.05) and fungi (9.4% vs 2.1%, P<0.05). There was no significant difference in the drug resistance rate of Gram-negative or Gram-positive bacteria between the two groups (P>0.05). CONCLUSIONS Enterobacteriaceae bacteria are the main pathogens of bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia, while the detection rates of Streptococcus mitis and fungi tend to increase as time, which needs to be taken seriously in clinical practice.
Anti-Bacterial Agents/therapeutic use* ; Bacteremia/drug therapy* ; Child ; Drug Resistance, Bacterial ; Gram-Negative Bacteria ; Humans ; Methicillin-Resistant Staphylococcus aureus ; Microbial Sensitivity Tests ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy* ; Retrospective Studies ; Sepsis/drug therapy*

OBJECTIVE: To investigate the clinical features, distribution of pathogenic bacteria, and drug resistance of bloodstream infection in children with acute leukemia. METHODS: Clinical data of 93 blood culture-positive children with acute leukemia from January 2015 to December 2019 in Department of Pediatrics, The Second Hospital of Anhui Medical University were analyzed retrospectively. RESULTS: In these 93 cases, 78 cases were in the period of neutrophil deficiency. There were 54 Gram-negative bacteria (G^-) (58.1%) found through blood culture, and the top 4 strains were Escherichia coli (15.1%), Klebsiella pneumoniae (13.9%), Pseudomonas aeruginosa (6.5%), and Enterobacter cloacae (6.5%). There were 39 Gram-positive bacteria (G⁺) (41.9%) detected, and the top 4 strains were Staphylococcus epidermidis (10.8%), Streptococcus pneumoniae (6.5%), Staphylococcus hemolyticus (5.4%), and Staphylococcus human (5.4%). Among 74 strains of pathogenic bacteria from acute lymphoblastic leukemia (ALL) children, there were 29 strains of G⁺ bacteria (39.2%) and 45 strains of G^- bacteria (60.8%). While in 19 strains from acute myeloblastic leukemia (AML) patients, G^- bacteria accounted for 47.4% and G⁺ bacteria accounted for 52.6%. In 15 ALL children without neutropenia, G⁺ bacteria made up the majority of the strains (66.7%). In the 93 strains of pathogenic bacteria, 13 (13.9%) strains were multidrug-resistant. Among them, extended-spectrum β-lactamases accounted for 42.9%, carbapenemase-resistant enzyme Klebsiella pneumoniae 15.4%, and carbapenemase-resistant enzyme Enterobacter cloacae strains 33.3%, which were detected from G^- bacteria. While, 13.3% of methicillin-resistant coagulase-negative Staphylococci accounted for 13.3% detected from G⁺ bacteria, but linezolid, vancomycin, teicoplanin Staphylococcus and Enterococcus resistant were not found. The average procalcitonin (PCT) value of G^- bacteria infection was (11.02±20.282) ng/ml, while in G⁺ infection it was (1.81±4.911) ng/ml, the difference was statistically significant (P<0.05). The mean value of C-reactive protein (CRP) in G^- infection was (76.33±69.946) mg/L, and that in G⁺ infection was (38.34±57.951) mg/L. The prognosis of active treatment was good, and only one case died of septic shock complicated with disseminated intravascular coagulation (DIC) and gastrointestinal bleeding caused by carbapenemase-resistant enzyme enterobacteriaceae. CONCLUSION G^- is the major bacteria in acute leukemia children with bloodstream infection, but the distribution of ALL and AML strains is different. G^- bacteria dominates in ALL, while G⁺ bacteria and G^- bacteria are equally distributed in AML. Non-agranulocytosis accompanied by bloodstream infections is dominant by G⁺ bacteria. The mean value of PCT and CRP are significantly higher in G^- bacteria infection than in G⁺ bacteria.
Acute Disease ; Anti-Bacterial Agents/therapeutic use* ; Bacteremia/microbiology* ; Bacteria ; Child ; Drug Resistance, Bacterial ; Humans ; Leukemia, Myeloid, Acute/drug therapy* ; Microbial Sensitivity Tests ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy* ; Procalcitonin ; Retrospective Studies ; Sepsis/drug therapy*

OBJECTIVE: To analyze the characteristics, prognosis and risk factors of bloodstream infection in patients with hematological malignancies in the tropics, so as to provide evidence for the prevention and treatment of bloodstream infection. METHODS: The clinical features, blood culture results and prognosis of patients with bloodstream infection in patients with hematological malignancies admitted to Hainan Hospital of PLA General Hospital were retrospectively studied. RESULTS: The most common primary infection site of the 81 patients with hematological malignancies was lung (46.91%), followed by PICC (11.11%). The detection rate of Gram-positive bacteria and Gram-negative bacteria in the blood culture was 60.98% and 30.02%, respectively. Coagulase-negative staphylococci was the most common Gram-positive bacteria resulting in bloodstream infection in our study. Of the Gram-negatives, Klebsiella pneumoniae (34.38%) was predominant, followed by Escherichia coli (18.75%) and Pseudomonas aeruginosa (18.75%). Gram-positive bacteria was highly sensitive (100%) to vancomycin, linezolid and tigecycline. Study showed that Gram-negative bacteria had low sensitive to quinolones, in particular, the resistance rate of Escherichia coli to quinolones was as high as 83.33%. In terms of overall survival (OS), the 30-days OS of patients with Gram-negative and Gram-positive septicemia was 77.42% and 92.00%, respectively. There was no statistically significant difference between the two groups. Multivariate analysis revealed that septic shock (P=0.001, RR=269.27) was an independent risk factor for 30-day mortality, and remission status (P=0.027, RR=0.114) was an independent predictor of a favourable outcome of bloodstream infection in patients with hematological malignancies. CONCLUSION Gram-positive bacteria are the main pathogens causing bloodstream infections in patients with hematological malignancies in the tropics. Improving the care of PICC is an important measure to reduce the incidence of bloodstream infection in patients with hematological malignancies in the tropics. A correct treatment relieving disease and effective prevention and treatment of septic shock can reduce mortality of patients with bloodstream infection in patients with hematological malignancies in the tropics.
Anti-Bacterial Agents/therapeutic use* ; Bacteremia/drug therapy* ; Drug Resistance, Bacterial ; Gram-Negative Bacteria ; Hematologic Neoplasms/drug therapy* ; Humans ; Microbial Sensitivity Tests ; Prognosis ; Retrospective Studies ; Sepsis

Anti-Bacterial Agents/therapeutic use* ; Bacteremia ; Carbapenems/therapeutic use* ; Cross Infection/drug therapy* ; Drug Resistance, Bacterial ; Humans ; Intensive Care Units ; Klebsiella Infections/drug therapy* ; Klebsiella pneumoniae ; Pneumonia/drug therapy* ; Risk Factors

OBJECTIVE: To investigate the phylogenetics and prevalence of bloodstream infections with ST131, the antimicrobial resistance profiles of the pathogens, and the clinical features. METHODS: Non-duplicate isolates were collected from 144 patients with bloodstream infections in our hospital between January and December, 2016.The phylogenetic groups of the isolates were analyzed using multiplex PCR, and O serotyping of ST131 strains was performed by allele-specific PCR.The clinical characteristics of the 144 patients were analyzed to define the differences in the clinical features between patients with ST131 infection and those with non-ST131 infection.Antibiotic susceptibility of the isolates was determined using the Vitek 2 compact system. RESULTS: The phylogenetic group analysis showed a domination by group B2 (41.0%[59/144]), followed by group F, group B1 and group E, which accounted for 16.7%(24/144), 13.9%(20/144), and 13.2% (19/144), respectively.Nine strains (6.3%) of were identified to be ST131 strains, among which 8 were O25b-B2-ST131 strains and 1 was O16-B2-ST131 strain.Of the 9 cases of ST131 infection, 7(77.8%) were found to occur in a nosocomial setting.The demographic characteristics and clinical features of the ST131-infected patients were similar to those of non-ST131-infected patients.ST131 strains were sensitive to piperacillin/tazobactam, imipenem, ertapenem, and amikacin, but showed high resistance rates to cefazolin, ceftriaxone, ciprofloxacin, levofloxacin, gentamicin, and trimethoprim/ sulfamethoxazole (all over 50%).The positivity rate of ESBLs in the ST131 strains was 77.8%, and the multidrug resistance rate reached 88.9%, which was higher than that of non-ST131 isolates, but the difference was not statistically significant. CONCLUSIONS The most common phylogenetic groups of isolates from patients with bloodstream infections are group B2 and F, and the positivity rate of ST131 is low.We for the first time detected O16-ST131 in patients with blood-borne infections in China.The clinical features of ST131-infected patients are similar to those of non-ST131-infected patients.The positivity rate of ESBLs and the multidrug resistance rate are high in ST131 strains, which may raise concerns in the future.
Anti-Bacterial Agents ; therapeutic use ; Bacteremia ; drug therapy ; epidemiology ; microbiology ; China ; Drug Resistance, Bacterial ; Escherichia coli ; classification ; drug effects ; genetics ; Escherichia coli Infections ; drug therapy ; epidemiology ; microbiology ; Genotype ; Humans ; Microbial Sensitivity Tests ; Molecular Epidemiology ; Phylogeny ; Species Specificity

Objectives: To investigate the influence of duration of antibiotic therapy on the prognosis of patients with AML who had Gram-negative bloodstream infection during consolidation chemotherapy. Methods: Data were collected retrospectively from 591 patients enrolled from the registered "A Phase III study on optimizing treatment based on risk stratification for acute myeloid leukemia, ChiCTR-TRC-10001202" treatment protocol between September 2010 and January 2016 in different treatment cycles. Results: A total of 119 episodes of Gram-negative bloodstream infection occurred during consolidation chemotherapy. Excluding the 5 episodes in which fever lasted longer than 7 days, 114 episodes of infection were analyzed. The median neutrophil count was 0 (0-5.62)×10(9)/L, median neutropenia duration was 9 (3-26) days, median interval of antibiotics administration was 7 (4-14) days. Logistic regression analysis showed that there is no significant difference on 3-day recurrent fever rate and reinfection by the same type bacteria between antibiotics administration ≤7 days or >7 days (1.2% vs 3.0%, P=0.522, OR=0.400, 95% CI 0.024-6.591; 18.5% vs 21.2%, P=0.741, OR=0.844, 95% CI 0.309-2.307). Propensity score analysis confirmed there was no significant difference on same pathogen infection rate between antibiotics application time ≤ 7 days or >7 days (P=0.525, OR=0.663, 95% CI 0.187-2.352). No infection associated death occurred within 7 or 30 days in both groups. Conclusion: Discontinuation of therapy until sensitive antibiotics treated for 7 days does not increase the recurrent fever rate and the infection associated death rate. Indicating that, for AML who had Gram-negative bloodstream infection during consolidation chemotherapy, short courses of antibiotic therapy is a reasonable treatment option when the infection is controlled.
Anti-Bacterial Agents/therapeutic use* ; Antineoplastic Combined Chemotherapy Protocols ; Bacteremia/drug therapy* ; Consolidation Chemotherapy ; Humans ; Leukemia, Myeloid, Acute ; Prognosis ; Retrospective Studies

OBJECTIVETo investigate the infections occurring in the induction period of childhood acute lymphoblastic leukemia (ALL), the pathogens of the infections, and drug resistance of isolated strains.

METHODSA retrospective analysis was performed for the clinical data of 130 children with newly-diagnosed childhood ALL. Infections occurring during the induction chemotherapy, pathogenic strains, and drug-resistance spectrum were analyzed.

RESULTSThe incidence rate of clinical infection and/or microbial infection reached 76.2%. The lungs were the most common infection site (46.2%). The children with severe infection accounted for 52.3%, among whom 60 had pulmonary infection and/or 21 had sepsis. A total of 50 pathogenic strains were detected, which consisted of 29 bacterial strains and 21 fungal strains. Of all the children, 28.5% experienced infections caused by at least one microbe. Among the 29 bacterial strains, there were 19 (65.5%) Gram-negative bacteria and 10 (34.5%) Gram-positive bacteria. The most common Gram-negative bacteria were Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa, which were 100% sensitive to imipenem. The most common Gram-positive bacterium was Streptococcus viridans, which was 100% sensitive to vancomycin. The infections caused by fungi accounted for 16.2%, with Candida albicans as the most common fungus. Compared with those with non-severe infections, the children with severe infections had a significantly shorter time to the occurrence of agranulocytosis, a significantly longer duration of agranulocytosis, significantly higher incidence of fever and C-reactive protein (CRP) level, and a significantly longer length of hospital stay (P<0.05).

CONCLUSIONSPulmonary infections are common in the induction period of childhood ALL. Gram-negative bacteria are the most common pathogenic bacteria. Severe infections can be controlled by carbapenems combined with vancomycin and antifungal agents.

Bacteremia ; drug therapy ; microbiology ; Bacteria ; isolation & purification ; Bacterial Infections ; drug therapy ; microbiology ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Humans ; Infant ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; complications ; Retrospective Studies