1.Analysis of the distribution characteristics and drug sensitivity of infection pathogens in hematology department ward.
Deng-Ju LI ; Wen-Li LIU ; Zi-Yong SUN ; Xu-Hui ZHU
Journal of Experimental Hematology 2004;12(6):861-865
The objective of this study was to investigate clinical distribution characteristics and drug sensitivity of infection pathogens in hematology department wards of our hospital during recent two years. The isolation and cultivation of pathogens from samples were performed by routine methods. Drug sensitivity tests of bacteria were performed by Kirby-Bauer method. Drug sensitivity tests of fungi were performed by ATBFUNGUS Drug sensitivity strips. The results showed that 102 strains of pathogens were isolated from all detected samples. The composition ratio of Gram-positive bacteria, Gram-negative bacteria and fungi was 42.2%, 34.3%, 3.5%, respectively. 58.8% of pathogens were isolated from samples of malignant hematopathy patients. 27.5% were isolated from samples of the patients with fever of unknown origin (FUO). 51.0% of pathogens were isolated from samples of the patients who suffered from agranulocytosis or leucocytopenia. Isolated fungi were mostly sensitive to anti-fungal drugs. G+ bacteria were most sensitive to vancomycin. G- bacteria were most sensitive to imipenem. Most bacteria were resistant to multiple antibiotics. It is concluded that the infection in hematology department wards was related with many conditions, such as weakened resistance of patients, leucocytopenia or agranulocytosis, tumor loading, etc. The prompt microbiological examination and drug sensitivity tests are important to rationally select antibiotics, reduce infection incidence and mortality rate, and decrease the occurrence of drug resistant strains.
Cross Infection
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microbiology
;
Fungi
;
drug effects
;
isolation & purification
;
Gram-Negative Bacteria
;
drug effects
;
isolation & purification
;
Gram-Positive Bacteria
;
drug effects
;
isolation & purification
;
Hematologic Diseases
;
microbiology
;
Humans
;
Imipenem
;
pharmacology
;
Microbial Sensitivity Tests
;
Vancomycin
;
pharmacology
2.Distribution and antibiotic resistance of pathogen isolated from mid-stream urine of 658 patients.
Journal of Central South University(Medical Sciences) 2010;35(11):1189-1195
OBJECTIVE:
To investigate the bacterial distribution and resistance to antibiotics in culture-positive urine, and to provide reference for rational use of antibiotics in clinical practice.
METHODS:
Distribution and antibiotic resistance to pathogens in 658 culture-positive patients from Jan. 1, 2007 to Dec. 31, 2008 were analyzed.
RESULTS:
(1)Pathogenic strains from the 658 patients were collected from the urine specimen in the survey, which included Gram-negative bacilli (70.82%), Gram-positive cocci (26.14%) and fungi (3.04%). The distribution rate of Escherichia coli declined from 68.91% in 2008 to 63.43% in 2007 (P>0.05), and Enterococcus rose from 3.37% to 7.67% (P>0.05), but the difference was not significant. The proportion of Gram-negative bacilli (especially the E.coli) from patients in the Emergency Department and Out-patient Department was higher than that from in-patients, and the proportion of K. pneumonia and Gram-positive bacteria was lower than in-patients, both with significant differences (P<0.05). (2) The resistance rate of E. coli and K. pneumonia to quinolones was 28.57%-56.25%, and the resistance rate to 3rd generation cephalosporin was 38.78%-65.78%, respectively. The resistance rate of Gram-positive cocci to quinolones and 3rd generation cephalosporin was both higher than 50%, and was 11.05% to Vancomycin.
CONCLUSION
Gram-negative bacilli such as E. coli and K. pneumonia are predominant organism in the urinary tract infections, but proportion of Gram-positive bacteria has increased in recent years. Attention needs to be paid to the overall and severe bacterial resistance in the urinary tract infections and rational use of antibiotics.
Adult
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Anti-Infective Agents, Urinary
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pharmacology
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Drug Resistance, Bacterial
;
Escherichia coli
;
drug effects
;
isolation & purification
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Female
;
Gram-Negative Bacteria
;
isolation & purification
;
Gram-Positive Bacteria
;
isolation & purification
;
Humans
;
Male
;
Retrospective Studies
;
Urinary Tract Infections
;
drug therapy
;
microbiology
;
Urine
;
microbiology
3.In Vitro Activity of Arbekacin Against Clinical Isolates of Staphylococcus species and Gram-negative Bacilli.
Jonghan LEE ; Chang Ki KIM ; Kyoung Ho ROH ; Hyukmin LEE ; Jong Hwa YUM ; Dongeun YONG ; Kyungwon LEE ; Yunsop CHONG
The Korean Journal of Laboratory Medicine 2007;27(4):292-297
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and some gram-negative bacilli are very prevalent nosocomial pathogens, commonly causing mixed infections, and are often resistant to multiple drugs. Arbekacin is an aminoglycoside used for the treatment of MRSA infections, but is also active against some gram-negative bacilli. The aim of this study was to determine in vitro activity of arbekacin against recent clinical isolates of staphylococci and gram-negative bacilli. Materials and METHODS: The strains were isolated from clinical specimens of patients at Severance Hospital in 2003. Antimicrobial susceptibility was tested by the Clinical and Laboratory Standards Institute agar dilution method. The following arbekacin breakpoints were used: susceptible, < or =4 microgram/mL; and resistant, > or =16 microgram/mL . RESULTS: All isolates of staphylococci tested were inhibited by < or =4 microgram/mL of arbekacin, regardless of their methicillin susceptibility. The MIC90s of arbekacin, 1-4 microgram/mL, were 8->32-fold and >32-128-fold lower than those of amikacin and gentamicin, respectively. The resistance rates of MRSA, methicillin-susceptible S. aureus, methicillin-resistant coagulase-negative staphylococci (CNS) and methicillin-susceptible CNS were 0% to arbekacin, 0-54% to amikacin, and 24-79% to gentamicin. The MIC90s of arbekacin for Escherichia coli and Citrobacter freundii, 1 microgram/mL and 16 microgram/mL, were 2-4-fold and 8-16-fold lower than those of amikacin and gentamicin, respectively. However, The MIC90s of arbekacin for other species of gram-negative bacilli, 64->128 microgram/mL, were similar to those of other aminoglycosides. CONCLUSIONS: Arbekacin may be a useful alternative to glycopeptides for the treatment of monomicrobial methicillin-resistant staphylococcal infections, as well as mixed infections with gram-negative bacilli, as most isolates of E. coli, C. freundii and some other gram-negative bacilli were also susceptible to arbekacin.
Anti-Bacterial Agents/*pharmacology
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Dibekacin/*analogs & derivatives/pharmacology
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Gram-Negative Bacteria/*drug effects/isolation & purification
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Gram-Negative Bacterial Infections/microbiology
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Humans
;
Methicillin Resistance
;
Microbial Sensitivity Tests
;
Staphylococcal Infections/microbiology
;
Staphylococcus aureus/*drug effects/isolation & purification
4.In Vitro Activity of Arbekacin Against Clinical Isolates of Staphylococcus species and Gram-negative Bacilli.
Jonghan LEE ; Chang Ki KIM ; Kyoung Ho ROH ; Hyukmin LEE ; Jong Hwa YUM ; Dongeun YONG ; Kyungwon LEE ; Yunsop CHONG
The Korean Journal of Laboratory Medicine 2007;27(4):292-297
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and some gram-negative bacilli are very prevalent nosocomial pathogens, commonly causing mixed infections, and are often resistant to multiple drugs. Arbekacin is an aminoglycoside used for the treatment of MRSA infections, but is also active against some gram-negative bacilli. The aim of this study was to determine in vitro activity of arbekacin against recent clinical isolates of staphylococci and gram-negative bacilli. Materials and METHODS: The strains were isolated from clinical specimens of patients at Severance Hospital in 2003. Antimicrobial susceptibility was tested by the Clinical and Laboratory Standards Institute agar dilution method. The following arbekacin breakpoints were used: susceptible, < or =4 microgram/mL; and resistant, > or =16 microgram/mL . RESULTS: All isolates of staphylococci tested were inhibited by < or =4 microgram/mL of arbekacin, regardless of their methicillin susceptibility. The MIC90s of arbekacin, 1-4 microgram/mL, were 8->32-fold and >32-128-fold lower than those of amikacin and gentamicin, respectively. The resistance rates of MRSA, methicillin-susceptible S. aureus, methicillin-resistant coagulase-negative staphylococci (CNS) and methicillin-susceptible CNS were 0% to arbekacin, 0-54% to amikacin, and 24-79% to gentamicin. The MIC90s of arbekacin for Escherichia coli and Citrobacter freundii, 1 microgram/mL and 16 microgram/mL, were 2-4-fold and 8-16-fold lower than those of amikacin and gentamicin, respectively. However, The MIC90s of arbekacin for other species of gram-negative bacilli, 64->128 microgram/mL, were similar to those of other aminoglycosides. CONCLUSIONS: Arbekacin may be a useful alternative to glycopeptides for the treatment of monomicrobial methicillin-resistant staphylococcal infections, as well as mixed infections with gram-negative bacilli, as most isolates of E. coli, C. freundii and some other gram-negative bacilli were also susceptible to arbekacin.
Anti-Bacterial Agents/*pharmacology
;
Dibekacin/*analogs & derivatives/pharmacology
;
Gram-Negative Bacteria/*drug effects/isolation & purification
;
Gram-Negative Bacterial Infections/microbiology
;
Humans
;
Methicillin Resistance
;
Microbial Sensitivity Tests
;
Staphylococcal Infections/microbiology
;
Staphylococcus aureus/*drug effects/isolation & purification
5.Distribution and drug resistance of pathogenic bacteria isolated from infected wounds of children after Wenchuan earthquake.
Ying-chun RAN ; Xiao-xiao AO ; Lan LIU ; Yi-long FU ; Hui TUO ; Feng XU
Chinese Journal of Pediatrics 2009;47(5):332-337
OBJECTIVETo investigate the distribution and the drug resistance pattern of pathogenic bacteria isolated from pediatric cases suffering from wounds infection following the Wenchuan earthquake.
METHODSOf the ninety-eight injured children, 50 had wound infection diagnosed by clinical examination. Specimens for culture were collected from the fifty injured children and the results of bacterial identification and antibiotic resistance were retrospectively reviewed.
RESULTSIn the fifty injured children with wound infection, microbial growth was detected in 31 (62.0%) and 21 children suffered from mixed infections (the infection rate was 67.7%). Ninety-nine pathogens were isolated, gram positive bacteria accounted for 16.16% (16 strains), Gram negative bacteria accounted for 81.82% (81 strains), and fungus 2.02% (2 strains). Staphylococcus aureus (5 strains, 5.05%), Enterococcus faecalis (3 strains, 3.03%) and Enterococcus faecium (2 strains, 2.02%) were the primary Gram-positive bacteria identified and Gram-negative infections typically included Acinetobacter baumanii (27 strains, 27.27%), Enterobacter cloacae (18 strains, 18.18%) and Pseudomonas aeruginosa (13 strains, 13.13%). Acinetobacter baumanii was the most common organism isolated from wounds. Duration of being szeged and complications had a significant association with wound infection with Acinetobacter baumanii. Drug sensitivity tests displayed that the isolated bacteria were highly resistant to common antibiotics. One strain of Acinetobacter baumanii-calcoaceticus complex and six strains of Acinetobacter baumanii were resistant to all common antibiotics including imipenem/cilastatin. Vancomycin-resistant Gram-positive bacteria were not identified.
CONCLUSIONFollowing the Wenchuan earthquake disaster, wound infection profiles of pediatric patients were significantly different, Acinetobacter baumanii was the main common organism isolated from wounds in contrast to the previous low isolation rate. The isolated bacteria were highly and multiple drug resistant and it was difficult to treat. Knowing the distribution and the drug resistance pattern of pathogen is of paramount importance in guiding the clinical treatment.
Adolescent ; Child ; Child, Preschool ; Disasters ; Drug Resistance, Bacterial ; Earthquakes ; Female ; Gram-Negative Bacteria ; drug effects ; isolation & purification ; Gram-Positive Bacteria ; drug effects ; isolation & purification ; Humans ; Male ; Microbial Sensitivity Tests ; Wound Infection ; microbiology ; Wounds and Injuries ; microbiology
7.Direct Identification and Antimicrobial Susceptibility Testing of Bacteria From Positive Blood Culture Bottles by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry and the Vitek 2 System.
Sung Jin JO ; Kang Gyun PARK ; Kyungja HAN ; Dong Jin PARK ; Yeon Joon PARK
Annals of Laboratory Medicine 2016;36(2):117-123
BACKGROUND: We evaluated the reliability and accuracy of the combined use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) bacterial identification and Vitek 2 antimicrobial susceptibility testing (AST) for bacteria from positive blood culture bottles. METHODS: Direct identification and AST were performed in parallel to the standard methods in monomicrobial positive blood culture bottles. In total, 254 isolates grown on aerobic and/or anaerobic bottles were identified with MALDI-TOF Vitek MS (bioMerieux, France), and 1,978 microorganism/antimicrobial agent combinations were assessed. For isolates from anaerobic bottles, an aliquot of the culture broth was centrifuged, washed, and filtered through a nylon mesh. For isolates from aerobic/pediatric bottles, a lysis step using 9.26% ammonium chloride solution and 2% saponin solution was included. RESULTS: The overall correct identification rate was 81.8% (208/254) and that for gram-positive/gram-negative isolates was 73.9%/92.6%, respectively, and it was 81.8%, 87.6%, and 57.9% for isolates from aerobic, anaerobic, and pediatric bottles, respectively. Identification was not possible in 45 cases, and most of these isolates were streptococci (N=14) and coagulase-negative staphylococci (N=11). Misidentification occurred only in one case. Compared with standard methods, direct AST showed 97.9% (1,936/1,978) agreement with very major error of 0.25%, major error of 0.05%, and minor error of 1.8%. CONCLUSIONS: This simple and cost-effective sample preparation method gives reliable results for the direct identification and AST of bacteria. For the identification of streptococci and coagulase-negative staphylococci, the method should be further improved.
Adult
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Ammonium Chloride/chemistry
;
Anti-Infective Agents/*pharmacology
;
Child
;
Gram-Negative Bacteria/drug effects/*isolation & purification/metabolism
;
Gram-Positive Bacteria/drug effects/*isolation & purification/metabolism
;
Humans
;
Reagent Kits, Diagnostic
;
Saponins/chemistry
;
*Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
8.Frequency distribution and antibiotic resistance of pathogens from the cerebrospinal fluid of 116 children with bacterial meningitis.
Hong-Chao JIANG ; Li-Yue KUI ; Hai-Lin HUANG ; Min SU ; Bo-Ping WEN
Chinese Journal of Contemporary Pediatrics 2013;15(4):264-267
OBJECTIVETo determine the frequency distribution and antibiotic resistance of pathogens isolated from the cerebrospinal fluid samples of children with bacterial meningitis (BM) and to provide a basis for the timely and effective treatment of childhood BM.
METHODSRetrospective analysis was performed on pathogens isolated from 5097 cerebrospinal fluid samples collected from children in Kunming Children's Hospital between January 2008 and June 2012, as well as drug sensitivity test results. Kirby-Bauer antibiotic testing was used to analyze the sensitivity of these pathogens to commonly used antibiotics.
RESULTSA total of 116 pathogen strains were detected from the 5097 cerebrospinal fluid samples, including 77 (66.4%) Gram-positive strains, 30 (25.9%) Gram-negative strains, and 9 (7.8%) fungal strains, with a positive rate of 2.28%. The six most frequently isolated pathogens were Staphylococcus epidermidis (32 strains, 27.6%), Streptococcus pneumoniae (15 strains, 12.9%), Escherichia coli (15 strains, 12.9%), Staphylococcus haemolyticus (9 strains, 7.8%), Cryptococcus neoformans (8 strains, 6.9%) and Staphylococcus aureus (6 strains, 5.2%). Coagulase-negative staphylococci was the predominant pathogen in neonates and young infants with BM, and its sensitivity rates to penicillin, erythromycin and clindamycin were lower than 40%. Streptococcus pneumoniae had a penicillin sensitivity rate of 13.4%, while sensitivity rates to erythromycin and clindamycin reached 60.0%. No Staphylococcus and Streptococcus pneumoniae pathogens resistant to vancomycin were found. Gram-negative bacilli had relatively high sensitivity rates to imipenem, meropenem, cefoperazone/sulbactam and cefepime.
CONCLUSIONSGram-positive cocci are the predominant pathogens for childhood BM over the past five years. The detected pathogens develop high resistance to commonly used antibiotics. To prevent misdiagnosis, careful attention should be paid to BM caused by Cryptococcus neoformans.
Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Gram-Negative Bacteria ; drug effects ; isolation & purification ; Gram-Positive Cocci ; drug effects ; isolation & purification ; Humans ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; cerebrospinal fluid ; drug therapy ; microbiology ; Retrospective Studies
9.Changes of pathogens and susceptibility to antibiotics in hematology ward from years 2001 to 2005.
Yun FAN ; Nai-Bai CHANG ; Yun-Jian HU ; Xiao-Man AI ; Shao-Quan XU ; Jiang-Tao LI ; Xi-Chun GU
Journal of Experimental Hematology 2008;16(6):1455-1458
The purpose of this study was to determine the changes of pathogens in hematological ward and susceptibility of patients received chemotherapy to antibiotics. The pathogens were taken from blood, urine and sputum of patients who accepted chemotherapy from years 2001 to 2005, then were isolated and identified. The susceptibility test was performed by disk diffusion method. The results showed that the total of 418 strains were detected. Gram-negative bacteria were the most common of nosocomial infection. Pseudomonas aeruginosa, Enterobacter cloacae, E. coli account for the most of Gram negative- bacteria infection and most resistant to broad-spectrum penicillin, Acinetobacter baumannii showed a trend of increase. The ratios of gram positive bacteria and fungi were increased slowly, mainly as Enterococcus and Candida. Enterococcus is the most common cause of Gram-positive bacterial infection. Vancomycin resistance did not occur. It is concluded that Gram-negative bacteria are main cause of nosocomial infection in patients with hematological malignancies. Gram positive bacteria and fungi had been more frequent. Strains resistant to antimicrobial agents increase.
Cross Infection
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epidemiology
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microbiology
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Drug Resistance, Bacterial
;
Gram-Negative Bacteria
;
drug effects
;
isolation & purification
;
Gram-Negative Bacterial Infections
;
epidemiology
;
microbiology
;
Hematologic Diseases
;
microbiology
;
Hematologic Neoplasms
;
microbiology
;
Humans
;
Microbial Sensitivity Tests
10.Common pathogens and clinical characteristics of neonatal pneumonia.
Hai-Juan WANG ; Hua SHI ; Wei ZHOU ; Zheng-Qiang HU ; Li-Yuan MU ; Min SU ; Yong-Mei JIANG
Chinese Journal of Contemporary Pediatrics 2012;14(12):898-902
OBJECTIVETo study common pathogens and their antibiotic susceptibility as well as clinical characteristics of neonatal pneumonia.
METHODSA retrospective study on neonatal pneumonia was performed. The study investigated antibiotic susceptibility of four common pathogens (339 strains) that caused neonatal pneumonia. Clinical characteristics of the newborns with pneumonia were analyzed. Of the 339 strains, 185 were isolated from bronchial secretions, 72 from blood samples, and 82 with positive results of both samples.
RESULTSFour hundred and seventy-four neonates with pneumonia presented positive results of bacterial culture. the most common pathogens Staphylococcus aureus (21.9%), Escherichia coli (19.2%), Klebsiella pneumoniae (19.0%) and Enterobacter cloacae (11.4%). The birth weight of newborns infected with Staphylococcus aureus was generally normal, and the time of hospital admission was later (after 24 hours of life). In contrast, the newborns with gram-negative bacterial infection, especially Klebsiella pneumoniae infection, had lower birth weights and early time of hospital admission (within 24 hours of life). Nearly more than 50% gram-negative bacteria were resistant to second, third and forth generation cephaloporins.
CONCLUSIONSGram-negative bacteria are predominant pathogens of neonatal pneumonia. Neonatal pneumonia caused by gram-negative bacteria is common in newborns with low birth weight and its onset time is relatively earlier. Gram-negative bacteria that cause neonatal pneumonia are highly resistant to cephaloporins.
Adult ; Birth Weight ; Drug Resistance, Bacterial ; Female ; Gram-Negative Bacteria ; drug effects ; isolation & purification ; Humans ; Infant, Newborn ; Male ; Maternal Age ; Microbial Sensitivity Tests ; Pneumonia ; microbiology ; Retrospective Studies