Objective: To understand the characteristics of bacterial meningitis after pediatric neurosurgical procedures. Methods: This was a retrospective observational study. From January 2016 to December 2022, 64 children diagnosed with post-neurosurgical bacterial meningitis based on positive cerebrospinal fluid (CSF) culture in Department of Neurosurgery of Shanghai Children's Medical Center were selected as the study population. The clinical characteristics, onset time, routine biochemical indexes of cerebrospinal fluid before anti infection treatment, bacteriology characteristics and sensitivity to antibiotics of bacteria cultured from cerebrospinal fluid were analyzed. Based on the CSF culture results, the patients were divided into the Gram-positive bacteria infection group and the Gram-negative bacteria infection group. The clinical characteristics of the two groups were compared using t-tests or Wilcoxon rank-sum tests, and chi-square tests. Results: There were 64 children,42 boys and 22 girls, with onset age of 0.83 (0.50, 1.75) years. Seventy cases of post-neurosurgical bacterial meningitis occurred in the 64 children, of which 15 cases (21%) in spring, 23 cases (33%) in summer, 19 cases (27%) in autumn, and 13 cases (19%) in winter. The time of onset was 3.5 (1.0, 10.0) months after surgery; 15 cases (21%) occurred within the first month after the surgery, and 55 cases (79%) occurred after the first month. There were 38 cases (59%) showing obvious abnormal clinical manifestations, fever 36 cases (56%), vomiting 11 cases (17%). Forty-eight cases (69%) were caused by Gram-positive bacteria, with Staphylococcus epidermidis 24 cases; 22 cases (31%) were caused by Gram-negative bacteria, with Acinetobacter baumannii the prominent pathogen 7 cases. The Gram-positive bacterial infection was more common in summer than the Gram-negative bacterial infection (20 cases (42%) vs. 3 cases (14%), χ²=5.37, P=0.020), while the Gram-negative bacterial infection was more in autumn and within the first month after surgery than the Gram-positive bacterial infection (11 cases (50%) vs. 8 cases (17%), 15 cases (67%) vs. 5 cases (33%), χ²=8.48, 9.02; P=0.004, 0.003). Gram-positive bacteria resistant to vancomycin and Acinetobacter baumannii resistant to polymyxin were not found. However, Acinetobacter baumannii showed only 45% (10/22) susceptibility to carbapenem antibiotics. Conclusions: The clinical presentation of post-neurosurgical bacterial meningitis in children is atypical. Gram-positive bacteria are the main pathogens causing post-neurosurgical bacterial meningitis; Gram-negative bacterial meningitis are more likely to occur in autumn and within the first month after surgery. Acinetobacter baumannii has a high resistance rate to carbapenem antibiotics, which should be taken seriously.
Male ; Female ; Humans ; Child ; China/epidemiology* ; Anti-Bacterial Agents/pharmacology* ; Meningitis, Bacterial/diagnosis* ; Gram-Negative Bacterial Infections/drug therapy* ; Gram-Positive Bacteria ; Gram-Positive Bacterial Infections/drug therapy* ; Carbapenems ; Retrospective Studies ; Microbial Sensitivity Tests ; Drug Resistance, Bacterial

PURPOSE: The aim of this study was to investigate the characteristics of Acute Kidney Injury Network (AKIN)-defined nephrotoxicity in patients undergoing intravenous colistimethate sodium (CMS) therapy for major burns. METHODS: This retrospective study included burn patients who received more than 48 h of intravenous CMS between September 2009 and December 2015. Data collection was performed using the institution's electronic medical record system. Patients assigned to the developed nephrotoxic group experienced aggravation of current AKIN stage during CMS treatment; those assigned to the non-nephrotoxic group experienced no change in current or exhibited improved AKIN stage during CMS therapy. RESULTS: A total of 306 patients were included in this study. All patients were grouped according to AKIN stage: AKIN 0 (n=152); AKIN 1 (n=6); AKIN 2 (n=9); AKIN 3 (n=139). The baseline creatinine (Cr) level was 0.73 mg/dL. The incidence of nephrotoxicity was 50.3% according to AKIN stage; overall mortality was 45.8%. The non-nephrotoxic group consisted of 127 (74.7%) patients and 43 (25.3%) were in the developed nephrotoxic group. In patients requiring continuous renal replacement therapy (CRRT), baseline Cr level was 0.83 mg/dL, pre-CMS Cr level was 1.17 mg/dL, and post-CMS Cr level was 1.34 mg/dL. CONCLUSION: CMS can be administered without signs of nephrotoxicity for a certain period (approximately 1 week), it can be used relatively safely for 2 weeks. Application of CMS is a reasonable option for treating infections caused by multi-drug resistant gram-negative bacteria in patients with major burns. The caution should be exercised nevertheless.
Acute Kidney Injury ; Burns ; Colistin ; Creatinine ; Data Collection ; Electronic Health Records ; Gram-Negative Bacteria ; Gram-Negative Bacterial Infections ; Humans ; Incidence ; Mortality ; Renal Replacement Therapy ; Retrospective Studies ; Sodium

OBJECTIVETo investigate the therapeutic effect and side effects of colistin in treating infections caused by multidrug-resistant (MDR) gram-negative bacillus in patients with severe burn in order to provide the basis for reasonable application of this antibiotic in clinic.

METHODSNine burn patients suffered from infections caused by MDR gram-negative bacillus admitted to our institute from August 2005 to January 2009 were involved in this study. On the premises that isolated bacteria were only sensitive to colistin or not sensitive to other antibiotics, patients were treated with intravenous drip of colistin (100 x 10(4) - 150 x 10(4) U/d), or intravenous drip combined with administration of the drug into respiratory tract by atomization or instillation (50 x 10(4) - 100 x 10(4) U/d). The bacteriologic and therapeutic effects and side effects (including neurotoxicity and nephrotoxicity, rise in serum levels of creatinine, urea nitrogen and cystatin C were detected and compared before and after administration) of colistin were observed.

RESULTSOut of 9 patients, 7 patients were with bloodstream and pulmonary infections, 1 patient was with bloodstream, pulmonary, and invasive wound infections, and 1 patient was with bloodstream and urinary tract infections. The pathogenic bacteria were proved to be Pseudomonas aeruginosa, Acinetobacter baumannii and Pseudomonas maltophilia. After the administration of colistin, bacteria clearance rate of blood reached 92.3% in 9 patients; isolation rate of MDR gram-negative bacillus of sputum was significantly decreased in 7 patients with pulmonary infection (before treatment 58.2% v.s. after treatment 14.6%, P < 0.01); a complete MDR gram-negative bacillus clearance of urine was observed in 1 patient with urinary tract infection. Colistin was clinically effective in 8 patients but ineffective in 1 patient (effective rate 88.9%). Compared with those before administration, serum levels of creatinine and urea nitrogen were decreased after administration in all patients; no significant difference in serum level of cystatin C among 8 patients was detected, except an obvious elevation in serum level of cystatin C in 1 patient after colistin therapy, and it lowered 1 month after discontinuation. No neurotoxicity or other side effect was observed during medication and 5 days after discontinuation in all patients.

CONCLUSIONSReasonable application of colistin is a good option for treating infections caused by MDR gram-negative bacillus in patients with severe burn, as no other more effective drug is found.

Adult ; Anti-Bacterial Agents ; adverse effects ; therapeutic use ; Burns ; drug therapy ; microbiology ; Colistin ; adverse effects ; therapeutic use ; Drug Resistance, Multiple, Bacterial ; Gram-Negative Bacteria ; drug effects ; Gram-Negative Bacterial Infections ; drug therapy ; Humans ; Male ; Middle Aged ; Treatment Outcome

OBJECTIVETo investigate the biological characteristics of phage SM1 for stenotrophomonas maltophilia (Sm) and its effect in animal infection model.

METHODSPhage SM1 isolated from raw sewage of hospital was identified by the plaque method. The morphology of phage SM1 was observed by electron micrographics with negative staining. The extraction and electrophoresis of phage SM1 DNA were performed. Optimal multiplicity of infection, resistant mutation rate, one step growth curve and the effectiveness in animal models of phage SM1 were determined.

RESULTSOne Sm specific phage of myoviridae double-stranded DNA was identified, and named SM1. Electrophoresis of DNA demonstrated that the size of phage SM1 genome was about 50 kb. The growth curve of phage SM1 showed that the durations of incubation and burst period were 15 min and 50 min, respectively; and the burst size was 187. The resistant mutation rate of phage SM1 was 6 x 10(-10). All mice treated with phage SM1 survived after 7 d of infection with stenotrophomonas maltophilia.

CONCLUSIONThe phage SM1 has a relatively broad host range, a shorter incubation period,an apparent burst size and a lower resistant mutation rate. The therapy of phage SM1 for Sm infection in mice is effective.

Animals ; Bacteriophages ; DNA, Viral ; genetics ; Disease Models, Animal ; Gram-Negative Bacterial Infections ; therapy ; Mice ; Mice, Inbred BALB C ; Stenotrophomonas maltophilia

Female ; Gram-Negative Bacterial Infections ; diagnosis ; drug therapy ; Humans ; Middle Aged ; Minocycline ; analogs & derivatives ; therapeutic use ; Stenotrophomonas maltophilia

Continued antimicrobial resistance surveillance can provide valuable information for the empirical selection of antimicrobial agents for patient treatment, and for resistance control. In this 6th annual study for 2002, the susceptibility data at 39 Korean Nationwide Surveillance of Antimicrobial Resistance (KONSAR) hospitals were analyzed. Resistance rates of S. aureus were 67% to oxacillin, and 58% to clindamycin. The ampicillin and vancomycin resistance rates of E. faecium were 89% and 16%, respectively. To penicillin, 71% of S. pneumoniae were nonsusceptible. Resistance rates of E. coli were 11% to cefotaxime, 8% to cefoxitin, and 34% to fluoroquinolone, and those of K. pneumoniae were 22% to ceftazidime, and 16% to cefoxitin. Lowest resistance rates to cephalosporins shown by E. cloacae and S. marcescens were to cefepime, 7% and 17%, respectively. This is the first KONSAR surveillance, which detected imipenem-resistant E. coli and K. pneumoniae. To imipenem, 22% of P. aeruginosa and 9% of Acinetobacter spp. were resistant. Trends of resistances showed a slight reduction in MRSA and in penicillin- nonsusceptible S. pneumoniae, but an increase in ampicillin-resistant E. faecium. Ampicillin-resistant E. coli and H. influenzae remained prevalent. Compared to the previous study, amikacin- and fluoroquinolone- resistant Acinetobacter spp. increased to 60% and 62%, respectively. Ceftazidime- resistant K. pneumoniae decreased slightly, and imipenem- resistant P. aeruginosa and Acinetobacter spp., and vancomycin-resistant E. faecium increased. In conclusion, vancomycin-resistant E. faecium, cefoxitin-resistant E. coli and K. pneumoniae, and imipenem-resistant P. aeruginosa and Acinetobacter spp. increased gradually, and imipenem- resistant E. coli and K. pneumoniae appeared for the first time. Continued surveillance is required to prevent further spread of these serious resistances.
Anti-Bacterial Agents/*therapeutic use ; Cefoxitin/*therapeutic use ; Drug Resistance, Bacterial ; Enterococcus/*drug effects ; Fluoroquinolones/therapeutic use ; Gram-Negative Bacterial Infections/*drug therapy/*epidemiology ; Gram-Positive Bacterial Infections/drug therapy/epidemiology ; Humans ; Imipenem/therapeutic use ; Korea/epidemiology ; Prevalence ; *Vancomycin Resistance

In the 1980s, Gram-negative pathogens appeared to have been beaten by oxyimino-cephalosporins, carbapenems, and fluoroquinolones. Yet these pathogens have fought back, aided by their membrane organization, which promotes the exclusion and efflux of antibiotics, and by a remarkable propensity to recruit, transfer, and modify the expression of resistance genes, including those for extended-spectrum beta-lactamases (ESBLs), carbapenemases, aminoglycoside-blocking 16S rRNA methylases, and even a quinolone-modifying variant of an aminoglycoside-modifying enzyme. Gram-negative isolates -both fermenters and non-fermenters-susceptible only to colistin and, more variably, fosfomycin and tigecycline, are encountered with increasing frequency, including in Korea. Some ESBLs and carbapenemases have become associated with strains that have great epidemic potential, spreading across countries and continents; examples include Escherichia coli sequence type (ST)131 with CTX-M-15 ESBL and Klebsiella pneumoniae ST258 with KPC carbapenemases. Both of these high-risk lineages have reached Korea. In other cases, notably New Delhi Metallo carbapenemase, the relevant gene is carried by promiscuous plasmids that readily transfer among strains and species. Unless antibiotic stewardship is reinforced, microbiological diagnosis accelerated, and antibiotic development reinvigorated, there is a real prospect that the antibiotic revolution of the 20th century will crumble.
Anti-Bacterial Agents/*therapeutic use ; *Drug Resistance, Bacterial/genetics ; Genotype ; Gram-Negative Bacteria/*drug effects/genetics/pathogenicity ; Gram-Negative Bacterial Infections/*drug therapy/*epidemiology/transmission ; Humans ; Phenotype ; Prevalence ; Treatment Failure

INTRODUCTIONPolymyxins have become the drug of choice for treatment of multidrug-resistant gram-negative bacilli infections in Singapore, simply because these pathogens are only susceptible to either aminoglycosides and polymyxins, or polymyxins only. Furthermore, there is no new antibiotic in the pipeline that targets these difficult-to-treat infections.

MATERIALS AND METHODSAll published literatures (up to end of February 2008) regarding polymyxins are included for review.

RESULTSThis review serves to give a summary of polymyxins from the current available literature, highlighting relevant clinical studies and information that help to guide informed prescription of polymyxins, should the need arise.

CONCLUSIONSHowever, there are substantial information gaps that needed to be filled urgently, to preserve the clinical utility of this very last line of antibiotic.

Anti-Bacterial Agents ; pharmacology ; therapeutic use ; Drug Resistance, Multiple, Bacterial ; Gram-Negative Bacteria ; drug effects ; Gram-Negative Bacterial Infections ; drug therapy ; microbiology ; Humans ; Microbial Sensitivity Tests ; Polymyxins ; pharmacology ; therapeutic use ; Singapore

OBJECTIVE: To study the distribution and drug sensitivity test of bacteria of patients on chronic rhinosinusitis with or without nasal polyps. METHOD: The purulent discharges were collected from sinus of 175 patients with chronic rhinosinusitis with or without nasal polyps during endoscopic sinus surgery. The results of germiculture and drug sensitivity test were analyzed. RESULT: From 175 specimens, 118 (67%) showed positive results in germiculture. Among them, 79 strains of gram positive bacteria and 39 strains of gram negative bacteria were detected. Staphylococcus epidermidis, Staphylococcus aureus and Staphylococcus haemolyticus were the most common pathogens in gram positive bacteria. The most common pathogens of gram negative bacteria were P. Aeruginosa, Enterobacter aerogenes, Enterobacter cloacae. The sensitive antibiotic on gram positive bacteria were amikacin, Daptomycin, Linezolid, vancomycin, teicoplanin, amoxicillin and clavulanate potassium, cefuroxime, respectively. The sensitive antibiotics on Gram negative bacteria were amikacin, Cefoperazone/sulbactam and imipenem, ceftazidime ceftazidime, aztreonam, levofloxacin, respectively. CONCLUSION Bacterial infection was common happened in the sinus cavity of patients with chronic rhinosinusitis with or without nasal polyps. Gram positive bacteria were the main pathogenic bacteria and gram positive bacteria and gram negative bacteria have great differences in the sensitivity of antibiotics. For patients with chronic rhinosinusitis, the using of antibiotics should depend on the drug sensitivity test.
Bacterial Infections ; complications ; drug therapy ; Gram-Negative Bacteria ; drug effects ; Gram-Positive Bacteria ; drug effects ; Humans ; Microbial Sensitivity Tests ; Nasal Polyps ; microbiology ; Rhinitis ; microbiology ; Sinusitis ; microbiology

OBJECTIVETo observe the clinical characteristics of infections in adult acute leukemia （AL）patients during chemotherapy in hospital, and identify the risk factors for infections.

METHODSA retrospective study of patients with AL who underwent chemotherapy between July 2010 and Dec 2014 in the First Affiliated Hospital of Xiamen University was conducted. Clinical features and risk factors for infections were analyzed.

RESULTS191 patients with AL received a total of 728 courses of chemotherapies. During these admissions, 385（52.9%) infections episodes occurred. The common infections sites were lower respiratory tract infection（36.3%，153/374）, bloodstream infection（17.1%, 64/374）, oral infection（13.6%，51/374）, and perianal infection（13.4%, 50/374）. 164 strains of pathogenic bacteria were detected. Gram- negative bacteria were recorded in 59.1% of documented pathogens, and Gram- positive bacteria were responsible for 32.9% of infections. Multivariate unconditioned logistic analysis of factors identified consistent independent risk factors for no completely remission（OR=0.142, P< 0.001）, duration of neutropenia longer than 7 days（OR=12.764, P<0.001）, general wards（OR=1.821, P< 0.001）, and hospitalization interval longer than 10 days（OR=0.720, P=0.039）.

CONCLUSIONInfections after chemotherapy for AL continues to be common. AL patients with induction chemotherapy or severe neutropenia faced an increased risk of infections by multivariate analysis. And patients with short-term stay or laminar flow wards seem to be less susceptible to infections.

Acute Disease ; Bacterial Infections ; complications ; Gram-Negative Bacteria ; Gram-Positive Bacteria ; Hospitals ; Humans ; Leukemia ; complications ; drug therapy ; microbiology ; Multivariate Analysis ; Neutropenia ; complications ; Remission Induction ; Retrospective Studies ; Risk Factors