Extended-spectrum beta -lactamase-producing enterobacteriaceae: in vitro susceptibility to fosfomycin, nitrofurantoin and tigecycline

To assess the susceptibility trends of community-acquired extended-spectrum beta -Iactamase [ESBL]-producing urinary isolates with particular reference to fosfomycin, nitrofurantoin and tigecycline. Seven hospitals across the United Arab Emirates participated in this study from June 2008 to March 2010. The antibiotic sensitivity of ESBL-producing uropathogens to a panel of antibiotics including tigecycline, fosfomycin and nitrofurantoin was assessed. The Hyplex ESBL identification system [h-ES-ID] was used for genotypic identification. Two hundred and ninety-two ESBL-producing Enterobacteriaceae isolates were identified during the study period. Of these, 182 [62%] were urinary isolates and comprised of Escherichia coli: 149 [81.9%], Klebsiella pneumoniae: 30 [16.5%] and Proteus mirabilis: 3 [1.6%]. Of the 182 urinary isolates, 179 [98.3%] were from patients with community onset urinary tract infections. The h-ES-ID system identified 172 [94.5%] of the urinary isolates as CTX-M positive. All isolates were susceptible to imipenem and meropenem. Over half of the isolates showed resistance to gentamicin [98; 53.8%], trimethoprim-sulfamethoxazole [139; 76.4%] and ciprofloxacin [143; 78.6%]. Sensitivity to nitrofurantoin and fosfomycin was 90 and 100%, respectively. Two CTX-M-positive K. pneumoniae isolates with tigecycline resistance [MIC >4 micro g/ml] were identified.There is dissemination of CTX-M ESBL-producing urinary pathogens into the community. Fosfomycin and nitrofurantoin were active against ESBL-positive uropathogens, and emergence of tigecycline resistance needs close monitoring

Molecular typing of methicillin-resistant staphylococcus aureus isolated in a Bahrain hospital

To investigate antibacterial resistance patterns and genetic relatedness of methicillin-resistant Staphylococcus aureus [MRSA] obtained at the Salmaniya Medical Complex in Bahrain. A total of 53 consecutive MRSA isolates obtained from 53 patients were studied using antibacterial resistance patterns, coagulase gene polymorphism, staphylococcal cassette chromosome mec [SCCmec] typing and pulsed-field gel electrophoresis [PFGE]. There was a high prevalence of resistance to fusidic acid [92.5%], ciprofloxacin [92.5%], erythromycin [90.6%], tetracycline [88.7%], trimethoprim [88.7%], streptomycin [88.7%], kanamycin [83.0%] and gentamicin [73.6%]. Coagulase gene typing divided the isolates into five coagulase types comprising coagulase type 36 [86.7%], type 20 [3.8%], type 16 [3.8%], type 38 [1.9%] and type 384 [3.8%]. They belonged to SCCmec type III [86.7%] and SCCmec type IV [13.3%]. PFGE identified five pulsotypes [types A-E] with PFGE type A and its subtypes comprising 83% of the isolates. PFGE type A isolates were multiresistant and had the SCCmec type Ill and coagulase type 36 genotype. The SCCmec type IV isolates were nonmultiresistant with different genetic backgrounds. The study identified two types of MRSA in the hospital during the study period. One type consisted of a persistent multiresistant PFGE clone with the SCCmec type Ill and coagulase type 36 genotypes. The second type consisted of nonmultiresistant isolates that belonged to different genetic backgrounds and were isolated less frequently

Incidence of bloodstream infections in a speciality hospital in Kuwait: 8-year experience

To determine the frequency of isolation and antibiotic-susceptibility patterns of clinically significant bacterial pathogens isolated from blood. The study was conducted over a period of 8 years [1995-2002] at Infectious Diseases Hospital [DH], Kuwait. Demographic and clinical data were obtained from medical records. 18,535 blood cultures were analyzed. Disk diffusion method was used to perform antibiotic-susceptibility testing. Minimum inhibitory concentrations of 9 antimicrobials were determined using E-test. Double disk [potentiation] test and E-test ESBL strips were used to detect the production of extended-spectrum beta-lactamases [ESBLs]. Salmonella spp. and Brucella spp. were predominant blood isolates, and represented 60.6 and 30.0% of all clinically significant episodes of bloodstream infections, respectively. Among the Salmonella, Salmonella enterica serotypes typhi and paratyphi A were most frequently isolated. The percentage of multidrug resistance [MDR] among them varied from 22 to 51%. A high percentage [40%] of MDR S. enterica serotypes typhi and paratyphi A also showed reduced susceptibility to ceftriaxone and ciprofloxacin. During the study period, Salmonella spp. and Brucella spp. were predominant blood isolates. MDR S. enter/ca serotypes typhi and paratyphiA, with reduced susceptibility to ceftriaxone and ciprofloxacin, are among the most frequent causes of bloodstream infections in IDH, suggesting the need to monitor their susceptibility

Seroepidemiological and microbiological study of brucellosis in Kuwait

The primary objective of the study was to determine the prevalence of brucellosis and the antimicrobial susceptibility pattern of local Brucellae isolates in the Infectious Diseases Hospital, Kuwait. Subjects and A single serum sample was collected from each of 1,836 patients of different nationalities from January 2000 to December 2001. Any patient with a provisional diagnosis of fever or brucellosis had a standard tube agglutination [STA] test for the quantitation of Brucella antibodies. Blood cultures were done in 166 of 455 patients with significant STA titers, using the Bactec system. Antimicrobial susceptibility testing of 123 isolates of Brucella spp. was done against 8 antimicrobial agents. A total of 455 serum samples [24.8%] having an STA titer of >/= 1:160 were presumptively diagnosed as cases of brucellosis. The peak isolation was in April and May. Brucella spp. were isolated from 123 blood cultures [74.1%]. The blood culture isolation rate was significantly higher in patients with an STA titer of >/= 1:1,280 than in those with an STA titer of

Antimicrobial susceptibility, phage typing and plasmid profile of salmonella enterica serotype paratyphi A strains isolated in Kuwait

To determine the antimicrobial susceptibility, phage type and plasmid profile pattern of Salmonella enterica serotype paratyphi A strains isolated in Kuwait. Material and From January 1995 to December 1999, 106 strains of S. enterica serotype paratyphi A isolated from an equal number of cases of enteric fever, attending the Infectious Disease and Mubarak Al-Kabeer Hospitals in Kuwait were investigated. The isolates were tested for antimicrobial susceptibility to 8 commonly used antimicrobial agents. Their phage type and plasmid profile patterns were determined using an international set of phages and Qiagen plasmid mini kit, respectively. All of the isolates were susceptible to ciprofloxacin, cefuroxime, ceftazidime, piperacillin and co-trimoxazole. One hundred isolates were susceptible to ampicillin, 99 to chloramphenicol and 98 to tetracycline. None of the isolates was multidrug resistant. Sixty-six% of the isolates were phage type I, 27.4% phage type II and 6.6% were untypable. All phage type I and untypable strains had 3 plasmids of 2.2, 5 and 20 kb, whereas phage type II strains had only 1 plasmid of 20 kb. The findings indicate that while all of the isolates of the S. enterica serotype paratyphi A were susceptible to 4 of the drugs tested, some were resistant to ampicillin, chloramphenicol or tetracycline, thereby indicating the need for continued surveillance and monitoring of antimicrobial susceptibility of these isolates

anaerobic bacteriology of intrapulmonary infections in Kuwait

The primary objective of this study was to ascertain the association of anaerobic bacteria in intrapulmonary infections and their susceptibility pattern to commonly prescribed antibiotics. One hundred clinical samples [85 broncho-alveolar lavage and 15 lung abscess aspirates] from suspected intrapulmonary infection cases were investigated in order to determine the role of anaerobic bacteria in these infections. The anaerobic bacterial isolates were identified by using the Vitek Anaerobic Card System and conventional methods. Susceptibility of these isolates was determined by Etest method against eight commonly prescribed antibiotics. A total of 42 anaerobes were isolated, of which Prevotella spp. were the commonest isolates, made up of 42.9% [18/42], followed by Peptostreptococcus spp. 33.3% [14/42]. Only two Bacteroides fragilis strains were isolated. All the isolates were sensitive to metronidazole, clindamycin, imipenem and meropenem; however, one Prevotella was resistant to piperacillin-tazobactam. The two B. fragilis isolates were susceptible to metronidazole, imipenem, meropenem and piperacillin-tazobactam, and one was found to be resistant to clindamycin. Overall, Prevotella spp. were found to be the predominant anaerobic bacteria associated with intrapulmonary infections in Kuwait. All the commonly prescribed antibiotics had excellent in vitro activities against nearly all the isolates