Surveillance of drug resistance of clinically isolated fungi strains from 46 hospitals in Shandong Province / 中华临床感染病杂志

Objective:To analyze the distribution of clinically isolated fungal strains and their resistance to common antifungal drugs in Shandong province.Methods:Through the Shandong Children’s Bacterial & Fungal Drug Resistance Surveillance and Research Collaborative Network, a total of 1 030 fungi were collected in 46 hospitals of Shandong province from January 1 to December 31, 2018. The source and type of strains were analyzed, and antifungal drug sensitivity tests were performed by using the micro-dilution method. Whonet 5.6 and SPSS 22.0 were applied to analyze the data.Results:The overall main strains were Candida albicans (38.74%, 399/1 030), Candida tropicalis (16.99%, 175/1 030) and Candida parapsilosis (16.41%, 169/1 030); the main fungi strains in child patients were C. albicans (52.50%, 63/120), C. parapsilosis (12.50%, 15/120) and C. tropicalis (9.17%, 11/120); the main fungi strains in adult patients were C. albicans (36.37%, 331/910), C. tropicalis (17.03%, 155/910) and C. parapsilosis (15.27%, 139/910). The isolation rate of main Candida strains from January to March and August to December was much higher than that of other months. The drug resistance rates of C. albicans to fluconazole and voriconazole were 7.14% and 7.43%, respectively, and the drug resistance rates to itraconazole were 50.44%. The resistance rates of C. tropicalis to fluconazole, voriconazole and itraconazole were 29.05%, 23.29% and 48.65%, respectively. The sensitivity rates of C. parapsilosi to fluconazole, voriconazole and itraconazole were 93.06%, 93.75% and 94.44%, respectively. Candida glabrata showed a dose-dependent sensitivity rate of 2.33% to fluconazole. Analysis of 244 blood fungi strains showed that non-candida albicans bacteremia accounted for 70.08%. In the pathogen spectrum covering 92.22%, fluconazole was sensitive to 64.65% of the pathogens, voriconazole was 68.88%, and amphotericin B was 88.75%. After quantification, the effective rates of fluconazole, voriconazole and amphotericin B in the clinical treatment of fungal bacteremia were 70.10%, 74.69% and 96.23%, respectively. Among them, the sensitivity rate of voriconazole to C. tropicalis was lower than that of fluconazole. Conclusions:Candida is the main clinical fungus isolates in hospitals of Shandong province. The resistance rate of C. tropicalis to azole antifungal drugs is on the rise, and the sensitivity of other Candida species to clinically used antifungal drugs is basically stable.

Study on Carbapenemase Genotype of Imipenem-resistant Gram-negative Bacilli in Intensive Care Unit of 3 Third Grade Class A Hospitals from Qingdao Area / 中国药房

OBJECTIVE: To analyze carbapenemases genotype of imipenem-resistant Gram-negative bacilli in intensive care unit (ICU) of 3 third grade class A hospitals from Qingdao area, so as to provide reference for drug-resistant bacteria infection prevention and treatment in clinic. METHODS: From Jan. 2013 to Jun. 2016, each 60 strains of imipenem-resistant Klebsiella pneumoniae (IRKP), imipenem-resistant Pseudomonas aeruginosa (IRPA) and imipenem-resistant Acinetobacter baumanii (IRAB) were collected from 3 third grade class A hospitals from Qingdao area. Drug sensitivity test was performed by using Kirby-Bauer method. Phenotypes of carbapenemases were determined by Carba NP trial. PCR was applied to amplify carbapenemase gene; Sanger seqnencing method was adopted for bi-directional sequencing; Blast comparison with GenBank database was conducted. RESULTS: Three kinds of imipenem-resistant Gram-negative bacilli showed high drug resistance to majority commonly used antibiotics as piperacillin, cefazolin, imipenem and cilastatin sodium, gentamicin, etc., but were sensitive to polymyxin B (resistance rate of 0). Among 180 drug-resistant strains, there were 52 strains of class A carbapenems, 13 strains of class B carbapenems and 39 strains of class D carbapenems; the detection rates of them were 28. 89％, 7. 22％ and 21. 67％, respectively. There were 52 strains of KPC-2 gene (IRKP), 4 strains of IMP-1 gene (IRPA), 8 strains of VIM-2 gene (7 strains of IRPA, 1 strain of IRAB), 39 strains of OXA-23 gene (IRAB); the detection rates of them were 28. 89％, 2. 22％, 4. 44％, 21. 67％; all strains were not detected 1MP-2, VIM-1, NDM-1, OXA-24, OXA-58 genes. Results of Blast comparison showed that above detected genes were absolutely homology with the corresponding genes in GenBank database. CONCLUSIONS: Drug resistance of imipenem-resistant Gram-negative bacilli in ICU of 3 third grade class A hospitals is serious in this region, which are nearly no-sensitive to most of commonly used antibiotics in clinic. Main genotypes included KPC-2 (K. pneumoniae), OXA-23 (A. baumanii) and IMP-1 and VIM-2 (P. aeruginosa).

Comparative study on two serological detection methods of mycoplasma pneumoniae in children with mycoplasmal pneumonia / 中国医师进修杂志

Objective To compare the sensitivity and specificity of dot immunogold method (DIM) and particle agglutination (PA) for the diagnosis of mycoplasma pneumoniae (MP) infection. Methods The 190 serum specimens of 113 children with mycoplasmal pneumonia (infection group) and 50 serum specimens of 50 health children (health group) were tested for MP by PA and DIM- A and B. Results In infection group, the positive rates of DIM- A and B were 82.63% (157/190) and 84.74%(161/190), and there was no statistical difference (χ2 = 0.31, P>0.05); the positive rate of PA (titer ≥1:160) was 70.00%(133/190), the positive rate of PA was significantly lower than that in DIM-A and B, and there were statistical differences (P0.05); the positive of PA was 8.00% (4/50), the positive rate of PA was significantly lower than that in DIM- A and B, and there were statistical differences (P<0.05 or<0.01). Conclusions Compared with the PA, DIM has low sensitivity and poor specificity for clinical diagnosis. DIM is not suitable for clinical diagnosis of MP infection.

A study on antibiotics resistance and carbapenemase genotype of Acinetobacter baumannii in intensive care unit of Qingdao / 中华检验医学杂志

Objective To investigate antibiotics resistant characteristics and carbapenemases genotype of Acinetobacter baumannii in Intensive Care Unit (ICU),so as to provide theoretical basis for clinical prevention and treatment.Methods Retrospective study was made on 90 non-duplicated clinical isolates of Acinetobacter baumannii,which were collected From January 2013 to January 2014 in three tertiary hospitals of Qingdao.All strains were identified by VITEK2 automated microbiology analyzer;K-B method was used to do drug susceptibility test;polymerase chain reaction (PCR) was used to amplify the OXA-23,OXA-24,OXA-51,OXA-58,KPC-2,VIM,IMP genes,and the positive products of genes were sequenced;the chi-square test was used to compare the difference of the resistance rates.Results The detection rate of multi-drug resistant A.baumannii (MDRAB)and Pan-drug resistant A.baumannii (PDRAB)was 61.11% (55/90) and 17.78% (16/90).In the 32 strains of imipenem-resistant Acinetobacter baumannii,the resistant rates to Cefoperazone/sulbactam,Polymyxin B was lower,while the resistant rates to other drugs tested were more than 85%.The difference of the resistance rates to 9 drugs between imipenem resistant group and Imipenem sensitive group were statistically significant (P≤0.05).PCR result showed: 32 strains detected OXA-51 gene,28 strains detected OXA-23 gene,and 3 strains detected VIM gene,the detection rates of which were 100%,87.50% and 9.38% respectively.All strains were not detected OXA-24,OXA-58,KPC-2 and IMP genes.The sequenced results were absolutely homology with the corresponding genes in genbank.Conclusions The resistance of A.baumannii in ICU is serious in this region,especially imipenem-resistant A.baumannii,which were nearly no-sensitive to most of the drugs commonly used in clinical.The gene existence of carbapenemase and carbapenemase producing is one of the main resistance mechanism of Acinetobacter baumannii to carbapenem antibiotics.OXA-23 was the major genotypes in this region.

Relationship Between Gene CYP51 and Clinical Azole-resistant Candida albicans Isolates / 中华医院感染学杂志

OBJECTIVE To explore the relationship between the point mutations of gene CYP51 and the azole-resistance mechanism in clinical Candida albicans isolates.METHODS The paper diffusion test and NCCLS M-27 protocols were used to screen the fluconazole-resistant and itraconazole-resistant C.albicans clinical isolates.Gene CYP51 of two azole-resistant C.albicans clinical strains(2007H and 2007T strains) was amplified by three pairs of primers,respectively.The PCR products purified were sequenced,and compared with the nucleotide sequences of C.albicans(accession No.:X13296) to find out the mutation sites.RESULTS The nucleotide sequence analysis showed that there were both significant point mutations and silent mutations in gene CYP51 from two azole-resistant isolates of C.albicans.Seven mutations previously described,F105L,K128T,Y132H,T199I,R267H,G464S,and R467K,were identified in the two strains.The animo acid substitutions of Y132H and R467K,known to contribution to azole resistance,were detected in both 2007H strain and 2007T strain.Four novel mutations,including F71L,W244R,T311N and T352I,were simultanously identified.Nine silent mutations appeared in two isolates.CONCLUSIONS In this survey,the two azole-resistant C.albicans clinical isolates contained more than one mutation in gene CYP51 that is associated with azole resistance.Four novel mutations of CYP51 may be associated with the resistance of C.albicans to azoles.And the mechanisms need to be further studied in detail.

Distribution of Pathogens and Their Antibiotic Resistance in Systemic Lupus Erythematosus Patients with Gram-negative Bacterial Infections / 中华医院感染学杂志

OBJECTIVE To study the distribution of pathogens and their antibiotic resistance in systemic lupus erythematosus(SLE)patients with gram-negative bacterial infections,for guiding the rational use of antibiotics therapy.METHODS The identification was analyzed by ATB Expression automatic microbiology analytical instrument system.The bacterial susceptibility test was done by Kirby-Bauer agar diffusion method.RESULTS Among 346 patients included,112(32.4%)had bacterial infections.A total of 181 pathogens strains had been isolated.Among 181 isolates,Escherichia coli,Pseudomonas aeruginosa,Klebsiella pneumoniae,Acinetobacter baumannii,Proteus mirabilis,and Enterobacter cloacae were the main pathogens.The ESBLs producing rates in E.coli and K.pneumoniae were 27.5% and 28.1%.Piperacillin/tazobactam and cefepime had less activity against A.baumannii and low resistant to other Gram-negative bacilli(0-46.2% and 13.0-33.3%).Meropenem,imipenem and cefoperazone/sulbactam showed greater activity against Gram-negative bacilli,their resistant rates were 0-17.1%,0-22.9% and 0-38.5%,respectively.CONCLUSIONS The clinical features of SLE patients with bacterial infections are lack of specificity.The data will be useful for reasonably choosing antimicrobial agents in the treatment of SLE patients with bacterial infections.

Detection of Metallo-?-lactamase and Antibiotics Resistance of Imipenem-resistant Pseudomonas aeruginosa in Qingdao Area / 中华医院感染学杂志

OBJECTIVE To find out the imipenem-resistan metallo-?-lactamase in P.aeruginosa to provide the proof of treatment for clinic.METHODS A multi-disk was used to detect the metallo-?-lactamase of P.aeruginosa and the K-B disk method was used for monitoring of the antibiotic-resistance to 15 antibiotics.RESULTS Fifteen strains producing metallo-?-lactamase were isolated from 93 imipenem-resistant P.aeruginosa strains.The positive rate with metallo-?-lactamase was 16.1%(15/93).The susceptibility tests showed the lower resistance was to cefoperazone sulbactam(Sulperazone),amikacin and piperacillinl tazobactam(Tazocin).their resistance rate respectively was 16.8%,24.8% and 26.6%.The resistance rate to ciprofloxacin and ceftazidime was 43.7% and 33.6%.The resistance rate over 90.0% was to ampicillin,ampicilillin/sulbactam,cefazolin,cefpodoxime,cefuroxime and so on.CONCLUSIONS P.aeruginosa with imipenem-resistance shows seriou multidrug-resistance.The metallo-?-lactamase is the main reason for P.aeruginosa resistance to imipenem and cephalosporins.The doctors should choose antibiotics reasonably according to the susceptibility test when taking effective treatment to P.aeruginosa infection.

Detections of HBV DNA and HBV Markers in Sera by Fluorescence Quantitative PCR and ELISA for Preventing Nosocomial Infection / 中华医院感染学杂志

OBJECTIVE To prevent nosocomial infection and increase the safety of blood supply so as to evaluate the feasibility of routine detections in screening blood donations for HBV DNA and HBV markers. METHODS(Three hundred blood) donors and 346 cases were detected by ELISA for HBV markers,and then performed by LightCycler for HBV DNA. RESULTS One(1.6%) of 62 negative samples of HBV markers in 346 cases was positive for HBV DNA.Out of 300 qualified donors in screening tests,six(2%) were positive for HBV DNA.And two(0.9%) of 222 negative samples of HBV markers were positive for HBV DNA. CONCLUSIONS This study shows that there are HBV infections with negative hepatitis B surface antigen(HBsAg) in population of Qingdao area and that incorporating fluorescence quantitative PCR into ELISA in screening blood donations for HBV infection will further increase the safety of blood supply and prevent nosocomial infections.