Campylobacter jejuni bacteremia and Helicobacter pylori in a patient with X-linked agammaglobulinemiaBruele, T.; Mourad-Baars, P.; Claas, E.; Plas, R.; Kuijper, E.; Bredius, R.
doi: 10.1007/s10096-010-0999-7pmid: 20556465
We describe a 15-year-old patient with X-linked agammaglobulinemia who developed malabsorption and bacteremia due to infection of Helicobacter pylori and Campylobacter jejuni. The Campylobacter bacteremia was only recognized after subculturing of blood culture bottles that failed to signal in the automated system. After 2 weeks of treatment with meropenem and erythromycin for 4 weeks, the patient developed a relapse of bacteremia 10 months later with a high level erythromycin resistant C. jejuni. Sequencing revealed an A2058C mutation in the 23 S rRNA gene associated with this resistance. Treatment with doxycycline for 4 weeks finally resulted in complete eradication. This case report illustrates the importance for physicians to use adapted culture methods and adequate prolonged therapy in patients with an immunodeficiency. A summary of published case reports and series of patients with hypogammaglobulinemia or agammaglobulinemia with Campylobacter or Helicobacter bacteremia is given.
Salmonellae in food stuffs of plant origin and their implications on human healthKrtinić, G.; Đurić, P.; Ilić, S.
doi: 10.1007/s10096-010-1001-4pmid: 20582445
Salmonella enterica is one of the most common causes of food-borne infection in human beings. Cases of Salmonella infection have been decreasing in Europe in the last ten years, yet, Salmonella infections are still the main cause of acute diarrhea syndrome. Globalization has caused the international food industry to increase the production of collective nutrition produce and products. This has intensified the need for authorized and accredited laboratories to monitor microbiological food safety. All parameters indicate the necessity of a multi-sector approach to this problem. Food safety supervision involves the analysis and identification of risk management, as well as the monitoring, evaluating, and regulating of crop irrigation. We can be more certain with a multi-sector approach that the number of Salmonella infections caused by plant-originated food stuffs will not increase in the future.
Epidemiological aspects of 2009 H1N1 influenza: the accumulating experience from the Northern HemisphereFalagas, M. E.; Cholevas, N. V.; Kapaskelis, A. M.; Vouloumanou, E. K.; Michalopoulos, A.; Rafailidis, P. I.
doi: 10.1007/s10096-010-1002-3pmid: 20623384
Preliminary data regarding the experience of countries of the Northern Hemisphere with pandemic 2009 A(H1N1) influenza have already appeared in the literature. We aimed to evaluate the available published literature describing the epidemiological features of pandemic influenza. We searched PubMed; 35 studies (14 referred to European countries, eight to the USA, five to Mexico, four to Canada, two to Japan, one to Colombia, and one reviewed relevant data reported worldwide) were included. Considerably high hospitalization, intensive care unit (ICU) admission, and fatality rates (up to 93.8, 36.4, and 38.5%, respectively) among the evaluated cases were reported across studies with available relevant data. Young and middle-aged adults constituted the majority of the evaluated pandemic cases, with different disease severity (as indicated by the level of care and outcome). Yet, substantial percentages of elderly individuals were reported among more severely afflicted cases. Otherwise healthy patients constituted substantial percentages among evaluated cases with different disease severity. Pregnant women, obese, and morbidly obese patients also constituted substantial percentages of the cases involved in the included studies. The evaluation of the currently available published evidence contributes to the clarification of the epidemiological features of pandemic 2009 A(H1N1) influenza, which is useful in terms of the individual and public health perspectives.
Distribution of 16S rRNA methylases among different species of Gram-negative bacilli with high-level resistance to aminoglycosidesZhou, Y.; Yu, H.; Guo, Q.; Xu, X.; Ye, X.; Wu, S.; Guo, Y.; Wang, M.
doi: 10.1007/s10096-010-1004-1pmid: 20614151
16S rRNA methylases confer high-level resistance to most aminoglycosides in Gram-negative bacteria. Seven 16S rRNA methylase genes, armA, rmtA, rmtB, rmtC, rmtD, rmtE and npmA, have been identified since 2003. We studied the distribution of methylase genes in more than 200 aminoglycoside-resistant Gram-negative clinical isolates collected in 2007 at our hospital in Shanghai, China. 16S rRNA methylase genes were amplified by polymerase chain reaction (PCR) among 217 consecutive clinical isolates of Gram-negative bacilli resistant to gentamicin and amikacin by a disk diffusion method. 16S rRNA methylase genes were present in 97.5% (193/198) of clinical isolates highly resistant to amikacin (≥512 μg/ml), with armA and rmtB detected in 67.2 and 30.3% of strains, respectively, while no 16S rRNA methylase genes were detected in 19 strains with amikacin minimum inhibitory concentration (MIC) ≤256 μg/ml. armA or rmtB genes were detected in 100% of 104 strains of Enterobacteriaceae, and these two genes were equally represented (49 vs. 55 strains). Genes for armA or rmtB were detected in 94.7% (89/94) of Acinetobacter baumannii and Pseudomonas aeruginosa strains, and armA was predominant (84 vs. 5 strains with rmtB). No rmtA, rmtC, rmtD or npmA genes were found. Enterobacterial repetitive intergenic consensus sequence (ERIC-PCR) indicated that armA and rmtB genes were spread by both horizontal transfer and clonal dissemination.
Risk factors of mid-term mortality of patients with infective endocarditisNomura, A.; Omata, F.; Furukawa, K.
doi: 10.1007/s10096-010-1006-zpmid: 20640585
In-hospital and long-term mortality of infective endocarditis (IE) are well noted, but the studies for mid-term (90-day) mortality of IE is still limited. We determine the mid-term mortality rate of IE and its significant predictors. Seventy patients with IE were hospitalised at St. Luke’s International Hospital between January 1996 and March 2009, of whom 62 consecutive patients could be followed up for 90 days after diagnosis. We then calculated Kaplan–Meier (KM) estimates and performed time-to-event analysis. The mean (standard deviation, SD) age was 66.6 (15.3) years. Thirty-five patients (56%) were male. Blood cultures were positive in 87%. Causative microorganisms were: viridans group streptococci (23%), β-streptococci (16%), Staphylococcus aureus (15%), including methicillin-resistant S. aureus (MRSA) (5%). Thirty-three cases (53%) had at least one complication such as heart failure (34%), central nervous system (CNS) complication (29%) or emboli peripheral to CNS (6%). KM estimates (95% CI) of the 90-day mortality was 14.5% (7.8–25%). In multiple regression analysis using the Cox proportional hazards model, hazard ratios of at least one complication for the 90-day mortality was 8.2 (1.4–155). Mid-term mortality of IE continues to be high and the presence of at least one complication may be considered as an independent risk factor of mid-term mortality.
In vitro and in vivo activities of linezolid alone and combined with vancomycin and imipenem against Staphylococcus aureus with reduced susceptibility to glycopeptidesRibes, S.; Pachón-Ibáñez, M.; Domínguez, M.; Fernández, R.; Tubau, F.; Ariza, J.; Gudiol, F.; Cabellos, C.
doi: 10.1007/s10096-010-1007-ypmid: 20680368
The objective of this study was to evaluate the in vitro and in vivo efficacies of linezolid (35 mg/kg/5 h), vancomycin (60 mg/kg/5 h), imipenem (30 mg/kg/5 h), linezolid+imipenem, linezolid+vancomycin and vancomycin+imipenem against two clinical Staphylococcus aureus isolates with reduced susceptibility to glycopeptides using time–kill curves and the murine peritonitis model. Time–kill curves were performed over 24 h. For the murine peritonitis model, peritonitis was induced by the intraperitoneal inoculation of 108 CFU/ml of each bacterial strain. Four hours later (0 h), the mice were randomly assigned to a control group or to therapeutic groups receiving subcutaneous treatment for 25 h. Bacterial counts in peritoneal fluid, bacteraemia and mortality rates were determined. The time–kill curves showed that the addition of linezolid to imipenem yielded synergistic results after 24 h. The addition of linezolid decreased vancomycin activity. In the animal model, vancomycin and linezolid monotherapies produced comparable bacterial decreases in mice infected with each strain but linezolid achieved higher rates of blood sterilisation. Linezolid tested either in monotherapy or in combination showed similar efficacy against both strains in terms of bacterial killing, number of negative blood cultures and survival. Linezolid and vancomycin were moderately bactericidal and similar in efficacy against glycopeptide-intermediate or -resistant S. aureus. Linezolid combinations, as effective as linezolid tested alone, could be considered as alternative options for the treatment of glycopeptide-intermediate S. aureus (GISA) infections.
In vitro activity of nemonoxacin, tigecycline, and other antimicrobial agents against Helicobacter pylori isolates in Taiwan, 1998–2007Yang, J.-C.; Lee, P.-I.; Hsueh, P.-R.
doi: 10.1007/s10096-010-1009-9pmid: 20658256
The minimum inhibitory concentrations (MICs) of 330 nonduplicate Helicobacter pylori isolates to nemonoxacin, tigecycline, and eight other antimicrobial agents were determined by using the agar dilution method. Sequencing the quinolone resistance-determining regions (QRDRs) in the gyrA gene of these isolates was also performed. Resistance to clarithromycin showed an increasing trend during the ten-year study period and was highest (38%) in 2005. Tigecycline had potent in vitro activities against all isolates, with an MIC90 of 0.06 μg/ml. Among the quinolones tested, nemonoxacin (MIC50 of 0.12 μg/ml and MIC90 of 0.25 μg/ml) and gemifloxacin had one to two-fold better in vitro activities than ciprofloxacin, levofloxacin, and moxifloxacin. Among the nine isolates (2.7%) with levofloxacin resistance, four (44.4%) were also resistant to metronidazole, three (33.3%) to clarithromycin, and two (22.2%) to amoxicillin. Isolates with levofloxacin resistance exhibited one or two of three amino acid alterations (Ser-70, Asn-87, and Asp-91) involved in QRDRs in the gyrA gene. A double mutation at Ser70Cys and Asn87Ile had a higher level of resistance. The results of this study suggest a potentially useful role of nemonoxacin and tigecycline in the treatment of infections caused by H. pylori. The gyrA mutation at Ser-70 is a novel finding and has an impact on levofloxacin resistance.
Use of recombinant chimeric antigens for the serodiagnosis of Mycoplasma pneumoniae infectionMontagnani, F.; Paolis, F.; Beghetto, E.; Gargano, N.
doi: 10.1007/s10096-010-1010-3pmid: 20632053
In this paper, we have evaluated the diagnostic utility of three antigenic regions of the Mycoplasma pneumoniae P1, P30, and MPN456 gene products in order to replace the soluble, whole-cell bacterial extract in serological assays. Antigenic regions, being previously identified as B-cell epitopes, were used individually or assembled in a recombinant chimeric antigen by genetic engineering. Paired serum samples from 47 patients with M. pneumoniae infection and from 39 subjects with a clinical picture of atypical pneumonia but without a defined diagnosis of M. pneumoniae infection were included. Immunoglobulin G (IgG) antibodies against epitopes carried by recombinant antigens were measured by performing recombinant enzyme-linked immunosorbent assays (Rec-ELISAs). Rec-ELISA results were compared to those obtained by a commercial assay using the whole-cell Mycoplasma antigen. Our study demonstrates that all IgG Rec-ELISAs using recombinant antigens have better sensitivity with respect to the commercial assay. Furthermore, we show that the use of chimeric antigens improve the performance of the assays. The use of recombinant antigens is effective in distinguishing M. pneumoniae-infected patients from uninfected individuals and shows that immunoassays based on recombinant antigens could provide the basis for standardized commercial tests for the serodiagnosis of M. pneumoniae diseases.
Prevalence of subtilase cytotoxin in verocytotoxin-producing Escherichia coli isolated from humans and raw meats in BelgiumBuvens, G.; Lauwers, S.; Piérard, D.
doi: 10.1007/s10096-010-1014-zpmid: 20680367
Recently, subtilase cytotoxin (SubAB) was detected in verocytotoxin-producing Escherichia coli (VTEC) that do not carry the Locus of Enterocyte Effacement (LEE) pathogenicity island. The distribution of the subA gene in VTEC isolated from patients with the hemolytic uremic syndrome, patients with diarrheal disease and raw meats from ruminants and wildlife in Belgium was investigated with PCR. The subA gene was detected more frequently (χ
2 = 10.2; d.f. = 1; P = 0.001) in VTEC from raw meats (10 of 87 strains) than in those from humans (8 of 274 strains), and never in serogroups O157, O26, O103, O111 and O145. This virulence marker could play a role in the development of HUS after infection with LEE-negative VTEC but was only found in one O178:H19 isolate out of 36 HUS-associated VTEC strains.