The aim of this study was to characterize the first two extended-spectrum cephalosporin-resistant and multidrug-resistant (MDR) Neisseria gonorrhoeae isolates collected from two sexually related patients (men who have sex with men) in Spain. Antimicrobial susceptibility was studied by Etest. Genes involved in quinolone, ceftriaxone and multidrug resistance were amplified by PCR and sequenced in both directions. The isolates were typed by N. gonorrhoeae multi-antigen sequence typing (NG-MAST). The two isolates had the same MDR profile, showing resistance to penicillin (MIC 0.094 mg/L; β-lactamase negative), ceftriaxone (MIC 1.5 mg/L), cefixime (MIC 1.5 mg/L), cefotaxime (MIC 1 mg/L), ciprofloxacin (MIC >32 mg/L) and tetracycline (MIC 1.5 mg/L). NG-MAST showed that both isolates belonged to sequence type (ST) 1407 (porB-908 and tbpB-110). Ciprofloxacin resistance was due to amino acid substitutions in GyrA (S91F and D95G) and ParC (S87R). An A deletion in the promoter of the MtrCDE efflux pump (mtrR) was detected. No changes were detected in the pilQ gene. The outer membrane protein PorB showed two substitutions at G120K and A121N. An L421P substitution was observed in the PBP1A (ponA) sequence. The sequence of PBP2 (penA) showed a mosaic structure related to genotype XXXIV with a single additional amino acid substitution (A501P). This genotype was identical to a recently described French isolate (F89). This is the first reported case of high-level extended-spectrum cephalosporin-resistant N. gonorrhoeae transmission. The molecular typing and MDR genotype suggest possible European spread of this strain, highlighting the need for surveillance and the importance of testing the susceptibility of N. gonorrhoeae to extended-spectrum cephalosporins.
An outbreak due to extended-spectrum β-lactamase-producing Klebsiella pneumoniae (ESBL-KP) was detected from May 1993 to June 1995. A total of 145 patients, particularly patients in intensive care units (ICUs) (107 patients [72%]), were colonized or infected. Infection developed in 92 (63%) patients, and primary bacteremia caused by ESBL-KP was the most frequent infection (40 of 92 patients [43%]). A single clone of ESBL-KP was identified by pulsed-field gel electrophoresis analysis throughout the whole period, and no molecular epidemiological relationship could be found between the epidemic strain and non-ESBL-KP isolates. To determine risk factors for ESBL-KP infection weekly rectal swabs were obtained in three serial incidence surveys (470 patients); the probabilities of carriage of ESBL-KP in the digestive tract were 33% (October and November 1993), 40% (May and June 1994), and 0% (October and November 1995) at 10 days of ICU admission. A logistic regression model identified prior carriage of ESBL-KP in the digestive tract (odds ratio, 3.4; 95% confidence interval 1.1 to 10.4) as an independent variable associated with ESBL-KP infection. A statistically significant correlation was observed between the restricted use of oxyimino-β-lactams (189 defined daily doses [DDD]/1,000 patient-days to 24 DDD/1,000 patient-days) and the trends of ESBL-KP infection ( r = 0.7; P = 0.03).
1 February 2016 in Clinical Microbiology and Infection
Fecal colonization with multiresistant Acinetobacter baumannii was evaluated in 189 consecutive patients in intensive care units (ICUs) during two different 2-month periods (October–November 1993 and May–June 1994). Rectal swabs were obtained weekly from admission to discharge from the ICU. Overall, 77 patients (41%) had multiresistant A. baumannii fecal colonization; colonization was detected in 55(71%) of the patients within the first week of their ICU stay. Clinical infections due to multiresistant A. baumannii occurred more frequently in patients with fecal colonization than in those without fecal colonization (26% vs. S%, respectively; P < .001). The reinforcement of isolation measures between study periods reduced both the number of fecal carriers of multiresistant A. baumannii (from 52% to 31%; P < .01) and the number of patients with multiresistant A. baumannii infections (from 17% to 11%; no statistical significance). The digestive tract of ICU patients could be an important epidemiologic reservoir for multiresistant A. baumannii infections in hospital outbreaks. Further prospective studies should be undertaken to define the relative significance of digestive tract colonization compared with other body site colonizations.