Nosocomial outbreak of CTX-M-15-producing E. coli in Norway

Seven E. coli isolates expressing resistance to 3rd generation cephalosporins were recovered from blood (n=2), kidney and lung tissue (n=1), and urinary tract (n=4) samples from seven patients hospitalised or recently discharged from the Divisions of Geriatrics and Pulmonary Medicine, Central Hospital of Rogaland, between July and September 2004. All isolates expressed a typical ESBL-cefotaximase profile (cefotaxime MIC>ceftazidime MIC) with clavulanic acid synergy. A bla(CTX-M-15) genotype was confirmed in six strains that were coresistant to gentamicin, nitrofurantoin, trimethoprim-sulfamethoxazole and ciprofloxacin. A bla(CTX-M-3) genotype was detected in the last strain. XbaI-PFGE patterns of the six bla(CTX-M-15) isolates revealed a clonal relationship. Bla(CTX-M-15) strains were also positive for the ISEcp1-like insertion sequences that have been shown to be involved in the mobilization of bla(CTX-M.) Further analyses revealed two bla(CTX-M-15)-positive E. coli urinary isolates clonally related to the outbreak strain from two different patients at the same divisions in January and February 2004. These patients were later re-hospitalised and one had E. coli with an ESBL-cefotaximase profile in sputum and nasopharyngeal specimen during the outbreak period. Clinical evaluation suggests that the CTX-M-producing E. coli strains contributed to death in three patients due to delayed efficient antimicrobial therapy. The outbreak emphasises the epidemic potential of multiple-antibiotic-resistant CTX-M-15-producing E. coli also in a country with low antibiotic usage and low prevalence of antimicrobial resistance.     

Multiplex PCR amplification assay for the detection of blaSHV, blaTEM and blaCTX-M genes in Enterobacteriaceae

Extended-spectrum beta-lactamases (ESBLs) are often mediated by (bla-)SHV, (bla)TEM and (bla)CTX-M genes in Enterobacteriaceae and other Gram-negative bacteria. Numerous molecular typing methods, including PCR-based assays, have been developed for their identification. To reduce the number of PCR amplifications needed we have developed a multiplex PCR assay which detects and discriminates between (bla-)SHV, (bla)TEM and (bla)CTX-M PCR amplicons of 747, 445 and 593 bp, respectively. This multiplex PCR assay allowed the identification of (bla-)SHV, (bla)TEM and (bla)CTX-M genes in a series of clinical isolates of Enterobacteriaceae with previously characterised ESBL phenotype. The presence of (bla)SHV, (bla)TEM and (bla)CTX-M genes was confirmed by partial DNA sequence analysis. Apparently, the universal well-established CTX-M primer pair used here to reveal plasmid-encoded (bla)CTX-M genes would also amplify the chromosomally located K-1 enzyme gene in all Klebsiella oxytoca strains included in the study.     

Comparison of drug susceptibility between Escherichia coli detected in stool cultures of patients undergoing transrectal prostate needle biopsy and Escherichia coli in hospital-wide urine antibiograms

A prostate biopsy is essential for prostate cancer diagnosis. However, infections are one of the biopsy-associated complications, and post-biopsy fever is estimated to occur in approximately 1% of all cases. It may thus be beneficial to perform a rectal swab culture before a transrectal prostate biopsy to confirm the presence of resistant bacteria and select preventive antibacterial agents according to the drug susceptibility results. This study aimed to determine whether there is a difference between the drug susceptibility of bacteria detected in the stool of patients who were scheduled to undergo prostate biopsy and the hospital-wide urine antibiogram. Patients suspected of having prostate cancer who underwent transrectal prostate biopsy via transrectal ultrasonography between August 1, 2016, and June 30, 2020, were included in this study. Stool samples were collected and cultured before biopsy. Overall, 99 patients underwent prostate biopsy, and of these, culture results were available for 81 patients (81.8%). Escherichia coli was detected in 74.0% (60 samples) of the stool culture samples, of which 4 samples were extended-spectrum β-lactamase-producing types. We found greater susceptibility of Escherichia coli to ampicillin, fluoroquinolones, sulfamethoxazole/trimethoprim, and cefixime in the stool culture antibiogram than in the hospital-wide urine antibiogram. We also found a significantly low incidence of ESBL-positive Escherichia coli in the stool culture antibiogram with p-values of 0.009, 0.007, and 0.03 compared to the hospital-wide urine antibiograms for 2017, 2018, and 2019, respectively. Stool culture of prostate cancer patients undergoing biopsy may provide useful information for selecting prophylactic antimicrobial agents.     

Monthly oral ibandronate is effective and well tolerated after 3 years: the MOBILE long-term extension

Oral ibandronate is the first bisphosphonate licensed for once-monthly treatment of postmenopausal osteoporosis. The 2-year Monthly Oral iBandronate In LadiEs (MOBILE) registration study assessed bone mineral density (BMD) and markers of bone turnover and showed that monthly oral ibandronate was at least as effective and well tolerated as a 2.5-mg daily oral regimen. In this study, we report the first year of a long-term extension study to MOBILE and a post hoc analysis of patients receiving 3 years of continuous treatment with monthly ibandronate. Patients who completed MOBILE were eligible for the partially randomized, double-blind extension study and received 100 mg (n = 359) or 150 mg (n = 360) monthly oral ibandronate. A post hoc analysis included patients who received either 100 mg (n = 173) or 150 mg (n = 169) monthly ibandronate continuously throughout the original 2-year MOBILE study and during the first year of the extension study. After one additional year of treatment (total of 3 years), mean lumbar spine BMD increased a further 1.5 and 1.1% in the 150 and 100 mg arms, respectively, compared with 2-year data (original MOBILE study). Total hip BMD changed by 0.3 and -0.08%, respectively. In the post hoc analysis, 3-year increases in lumbar spine BMD were significant in patients receiving ibandronate 150 mg monthly (7.6%; p < 0.0001 vs. baseline) and 100 mg monthly (6.4%; p < 0.0001 vs. baseline). Both groups achieved significant increases in total hip BMD after 3 years compared with baseline (3.4%, 100 mg; 4.1%, 150 mg; p < 0.0001). Serum C-telopeptide of the alpha chain of type I collagen decreased significantly over 3 years' treatment (p < 0.001; all comparisons vs. baseline), remaining within the premenopausal range. Once-monthly oral ibandronate was well tolerated with a low incidence of clinical osteoporotic fractures and upper gastrointestinal events. In conclusion, 150-mg monthly oral ibandronate is an effective and well-tolerated long-term treatment for postmenopausal osteoporosis, with consistent improvement in BMD and bone turnover during 3 years' continuous treatment.     

日益增多的超广谱β内酰胺酶CTX-M酶

在头孢噻肟应用于临床数年后CTX-M酶开始出现，至1995年已在全球范围流行。如今，已成为南美，远东和东欧等地区需严重关切的问题。此酶基因的前身为克鲁维尔菌的染色体β内酰胺酶，通过各种移动元件，包括ISEcp 1和orf513转移给肠杆菌科细菌而广泛传播，CTX-M酶对头孢噻肟的水解活性明显高于头孢他定，后者的MIC常在敏感范围之内，故对ESBLs的筛查不能只用头孢他定。CTX-M酶对头孢噻肟的水解活性与其结构omega环和β3肽链有关。近年发现，在头孢他定的选择压力下，增强了耐头孢他定的变异酶也在增多。     

环磷酰胺冲击治疗小儿难治性肾病28例疗效观察

目的：观察环磷酰胺冲击治疗小儿难治性肾病疗效。方法：环磷酰胺冲击治疗小儿难治性肾病２８例，每２周１次，每次８～１２ｍｇ／ｋｇ，连用２ｄ。其中频反复及频复发６例，激素耐药２２例，经肾活检８例，其中系膜增殖型肾类４例，膜增殖性肾小球肾炎１例，局灶节段性肾小球硬化１例，膜性肾病１例，增生硬化性肾炎１例。结果：总有效率９６％，完全缓解２４例，部分缓解３例。无效１例，６例频反复频复发病例中，４例获长期缓解，１例复发，１例失访。结论：环磷酰胺冲击治疗小儿难治性肾病疗效显著，缓解率高，副作用相对少。是目前治疗小儿难治性肾病强有力的手段和重大进展。     

Effective high-dose chemotherapy with autologous bone marrow infusion in resistant ovarian cancer

Two patients with persistent minimal ovarian cancer after conventional polychemotherapy were treated with high doses of cyclophosphamide and VP 16-213 followed by autologous bone marrow infusion. Ten months afterward no clinical signs of tumor were apparent. In one patient the complete response was surgically documented. Toxicity included cardiac and pulmonary arrest during marrow infusion in one patient, but was otherwise manageable. This method of late intensification of chemotherapy in patients with persisting ovarian cancer merits further investigation.     

Brain distribution of genes related to changes in locomotor activity

The relationship between genes and behavior, and particularly the hyperactive behavior, is clearly not linear nor monotonic. To address this problem, a database of the locomotor behavior obtained from thousands of mutant mice has been previously retrieved from the literature. Data showed that the percent of genes in the genome related to locomotor hyperactivity is probably more than 1.56%. These genes do not belong to a single neurotransmitter system or biochemical pathway. Indeed, they are probably required for the correct development of a specific neuronal network necessary to decrease locomotor activity. The present paper analyzes the brain expression pattern of the genes whose deletion is accompanied by changes in locomotor behavior. Using literature data concerning knockout mice, 46 genes whose deletion was accompanied by increased locomotor behavior, 24 genes related to decreased locomotor behavior and 23 genes not involved in locomotor behavior (but important for other brain functions) have been identified.These three groups of genes belonged to overlapping neurotransmitter systems or cellular functions. Therefore, we postulated that a better predictor of the locomotor behavior resulting from gene deletion might be the brain expression pattern. To this aim we correlated the brain expression of the genes and the locomotor activity resulting from the deletion of the same genes, using two databases (Allen Brain Atlas and SymAtlas). The results showed that the deletion of genes with higher expression level in the brain had higher probability to be accompanied by increased behavioral activity. Moreover the genes that were accompanied by locomotor hyperactivity when deleted, were more expressed in the cerebral cortex, amygdala and hippocampus compared to the genes unrelated to locomotor activity. Therefore, the prediction of the behavioral effect of a gene should take into consideration its brain distribution. Moreover, data confirmed that genes highly expressed in the brain are more likely to induce hyperactivity when deleted. Finally, it is suggested that gene mutations linked to specific behavioral abnormalities (e.g. inattention) might probably be associated to hyperactivity if the same gene has elevated brain expression.     

Protective effect of zinc supplementation against cadmium-induced oxidative stress and the RANK/RANKL/OPG system imbalance in the bone tissue of rats

It was investigated whether protective influence of zinc (Zn) against cadmium (Cd)-induced disorders in bone metabolism may be related to its antioxidative properties and impact on the receptor activator of nuclear factor (NF)-κΒ (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) system. Numerous indices of oxidative/antioxidative status, and Cd and Zn were determined in the distal femur of the rats administered Zn (30 and 60 mg/l) or/and Cd (5 and 50 mg/l) for 6 months. Soluble RANKL (sRANKL) and OPG were measured in the bone and serum. Zn supplementation importantly protected from Cd-induced oxidative stress preventing protein, DNA, and lipid oxidation in the bone. Moreover, Zn protected from the Cd-induced increase in sRANKL concentration and the sRANKL/OPG ratio, and decrease in OPG concentration in the bone and serum. Numerous correlations were noted between indices of the oxidative/antioxidative bone status, concentrations of sRANKL and OPG in the bone and serum, as well as the bone concentrations of Zn and Cd, and previously reported by us in these animals (Brzóska et al., 2007) indices of bone turnover and bone mineral density. The results allow us to conclude that the ability of Zn to prevent from oxidative stress and the RANK/RANKL/OPG system imbalance may be implicated in the mechanisms of its protective impact against Cd-induced bone damage. This paper is the first report from an in vivo study providing evidence that beneficial Zn impact on the skeleton under exposure to Cd is related to the improvement of the bone tissue oxidative/antioxidative status and mediating the RANK/RANKL/OPG system.     

The first major extended-spectrum beta-lactamase outbreak in Scandinavia was caused by clonal spread of a multiresistant Klebsiella pneumoniae producing CTX-M-15

Between May and December 2005, 64 multidrug-resistant isolates of Klebsiella pneumoniae were detected from patients admitted to Uppsala University Hospital. This represented a dramatic increase in ESBL-producing K. pneumoniae compared to previous years. To investigate the epidemiology and to characterize the resistance mechanisms of the isolates, a study was initiated. Antibiotic susceptibility was determined by means of the Etest and the disc diffusion method. Extended-spectrum beta-lactamase (ESBL) production was identified by clavulanic acid synergy test and confirmed with PCR amplification followed by DNA sequencing. DNA profiles of the isolates were examined with pulsed-field gel electrophoresis (PFGE). All isolates were resistant or exhibited reduced susceptibility to cefadroxil, cefuroxime, cefotaxime, ceftazidime, aztreonam, piperacillin/tazobactam, ciprofloxacin, tobramycin, and trimethoprim-sulfamethoxazole. They produced ESBL of the CTX-M-15 type, and the involvement of a single K. pneumoniae clone was shown. This is the first major clonal outbreak of multiresistant ESBL-producing K. pneumoniae in Scandinavia. The outbreak demonstrates the epidemic potential of enterobacteria containing ESBLs of the CTX-M type, even in a country with a relatively low selective pressure and a low prevalence of multiresistant bacteria.