Prevalence of subtilase cytotoxin in verocytotoxin-producing Escherichia coli isolated from humans and raw meats in Belgium.

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.

Correction of underquantification of human immunodeficiency virus type 1 load with the second version of the Roche Cobas AmpliPrep/Cobas TaqMan assay.

Initial evaluations of the Cobas AmpliPrep/Cobas TaqMan human immunodeficiency virus type 1 (HIV-1) test (CAP/CTM) demonstrated good performance but, afterwards, reports about underquantification were published. We investigated whether the problem was solved with a second version of this assay, the Cobas AmpliPrep/Cobas TaqMan HIV-1 test, version 2.0 (CAP/CTM v2.0). The remaining plasma of 375 consecutive HIV-1 positive samples with a viral load of >or=4,000 copies/ml was collected in three laboratories. The samples were diluted and retested with our routine method Cobas AmpliPrep/Cobas Amplicor HIV-1 monitor test v1.5 in ultrasensitive mode (CAP/CA PHS), as well as with the CAP/CTM and CAP/CTM v2.0 tests. An absolute difference between the results of two methods of >or=0.71 log(10) copies/ml was defined as moderately discrepant, and an absolute difference of >or=0.93 log(10) copies/ml was defined as severely discrepant. In addition, criteria for considering the new methods equivalent to the routine method were formulated. (i) For CAP/CTM compared to CAP/CA PHS, 36 (9.5%) and 20 (5.3%) samples were, respectively, considered moderately and severely underquantified by CAP/CTM. The mean difference between CAP/CTM and CAP/CA PHS was -0.32 log(10) copies/ml. Eight of nineteen of the severely underquantified samples were from patients infected with HIV-1 subtype B strain. (ii) For CAP/CTM v2.0 compared to CAP/CA PHS, no sample was moderately or severely underquantified by CAP/CTM v2.0. A mean difference of 0.08 log(10) copies/ml was found with CAP/CTM v2.0 compared to CAP/CA PHS. The underquantification problem of the CAP/CTM kit was clearly demonstrated. The criteria for the equivalence of CAP/CTM v2.0 to the routine test CAP/CA PHS were fulfilled.

First sorbitol-fermenting Verocytotoxin-producing Escherichia coli O157: H- isolated in Belgium.

We report a case of haemolytic uraemic syndrome (HUS) following an infection with a sorbitol-fermenting Verocytotoxin-producing Escherichia coli (VTEC) O157:H- in a toddler living in the province of East Flanders, Belgium. The patient presented with haemolytic anaemia, haematuria, proteinuria, renal insufficiency, and thrombocytopaenia leading to the diagnosis of HUS. Risk factors for VTEC infection, such as consuming undercooked food of bovine origin and direct contact with farm animals were absent. Also, neither travelling nor contact with travellers were reported. The patient recovered after perfusion with fresh frozen plasma and blood transfusion, and dialysis was not required. This is the first isolation of a sorbitol-fermenting VTEC O157:H- in Belgium. Future research is needed to reveal epidemiologic aspects, such as the main reservoir and transmission routes of this pathogenic E. coli serotype, which has caused outbreaks of HUS in Germany and Scotland.

Outbreak of multidrug-resistant Acinetobacter baumannii in a Belgian university hospital after transfer of patients from Greece.

Multidrug-resistant (MDR) Acinetobacter baumannii are emerging as important nosocomial pathogens. These organisms have a capacity for long-term survival in the hospital environment. The purpose of this study was to describe the course and control of an outbreak with MDR A. baumannii in a Belgian university hospital after transfer of two trauma patients from Greece. Wounds in both patients were colonised with MDR A. baumannii. Over an 11 month period from September 2004 to July 2005, carbapenem-non-susceptible A. baumannii (producing carbapenem-hydrolysing oxacillinase OXA-58) were isolated from 28 patients, despite early implementation of contact precautions. MDR A. baumannii was detected in routine clinical diagnostic samples from 26 patients and in screening specimens from an additional two patients. Twenty patients (71.4%) were colonised or infected during their stay in intensive care. Twenty-four (85.7%) respiratory samples were positive for MDR A. baumannii. Careful review of all procedures related to the respiratory tract did not identify a common route of transmission. Outbreak control required multiple interventions, including contact isolation of colonised and infected patients, monitoring the practice of personnel, screening of asymptomatic patients, use of isolation rooms and enhanced environmental disinfection. Introduction of single-use ventilator circuits was considered but the outbreak was controlled before implementation.

Biologically active bisbenzylisoquinoline alkaloids from the root bark of Epinetrum villosum.

Methanol and water extracts of the root of Epinetrum villosum (Exell) Troupin (Menispermaceae) were found to exhibit antimicrobial and antiplasmodial activities. Investigation of the active methanol fraction led to the isolation of four bisbenzylisoquinoline alkaloids, i.e., cycleanine, cycleanine N-oxide, isochondodendrine and cocsoline. Structures were established by spectroscopic methods. Cocsoline displayed antibacterial and antifungal activities (MIC values of 1000-15.62 and 31.25 microg/ml, respectively). Isochondodendrine was found to have the most potent antiplasmodial activity (IC50 = 0.10 microg/ml), whereas the IC50 on HCT-116 human colon carcinoma cells was 17.5 microg/ml (selectivity index 175). Cycleanine acted against HIV-2 (EC50=1.83 microg/ml) but was at least 10-fold less active against HIV-1. Cycleanine N-oxide showed no activity towards all tested microorganisms.

External quality assessment for molecular detection of Bordetella pertussis in European laboratories.

Although the PCR for the detection of Bordetella pertussis is routinely performed in diagnostic laboratories, no quality assessment program has so far been described. We report on the results obtained with two external quality assessment proficiency panels sent to European laboratories. The first proficiency panel contained a series of dilutions of three previously characterized B. pertussis clinical isolates and two negative controls. No false-positive results were reported by six laboratories providing seven data sets. The reported limits of detection of the three B. pertussis strains varied between 4 and 4,000, 9 and 9,000, and 3 and 30,000 CFU/ml, respectively. The second proficiency panel, composed of a series of dilutions of reference strains of B. pertussis, B. holmesii, B. hinzii, and B. bronchiseptica, as well as negative controls, was sent to nine laboratories. One laboratory reported a negative result for a sample and reported a B. parapertussis-positive sample to be positive for B. pertussis. By using the B. pertussis-specific target gene pertactin, one laboratory detected B. pertussis with 100% specificity. All other laboratories, which used IS481-based assays, reported positive results for the samples containing B. holmesii and B. bronchiseptica, species that have occasionally been recovered from human respiratory samples. These data show that the choice of the target gene is particularly critical for the species specificity of B. pertussis PCR assays.

Salmonella enterica subspecies houtenae serotype 44:z4, z23:--as a rare cause of meningitis.

Reptiles can carry and shed the bacterium Salmonella without showing any signs of illness. Transmission occurs by ingesting Salmonella after handling a reptile or objects contaminated by a reptile. Young children are especially vulnerable to Salmonella infection and can experience serious complications. We describe a case of reptile-associated Salmonella meningitis in a 2.5-month-old infant.

[Screening for Staphylococcus aureus with a reduced susceptibility to vancomycin in: a Belgian hospital]. / Recherche de Staphylococcus aureus à sensibilité diminuée à la vancomycine dans un hôpital Belge.

The aim of the present study was to investigate the prevalence of vancomycin resistance in clinical methicillin resistant Staphylococcus aureus (MRSA) isolates in our hospital by screening on Mueller-Hinton agar with 5 mg/l teicoplanin (MH-Teico), as recommended by the Comite de l'Antibiogramme of the Societe Francaise de Microbiologie (CA-SFM). Seventeen of 1002 clinical MRSA isolated from 404 patients showed in 2003 growth of at least four colonies on this medium, but only one was confirmed as homogeneous vancomycin-resistant S. aureus (VISA) and five as heterogeneous VISA (hVISA) by population analysis. None of the patients presented with severe infection but awareness is needed and screening on MH-Teico as recommended by CA-SFM is a convenient method. Surveillance should be focused on patients with risk factors for selection of such strains: patients with a prolonged course of glycopeptide therapy and persistence of MRSA infection or colonization.

Quantitative RT-PCR ELISA to determine the amount and ratio of positive- and negative strand viral RNA synthesis and the effect of guanidine in poliovirus infected cells.

Quantitative reverse transcription-polymerase chain reaction enzyme linked immunosorbent assay (RT-PCR ELISA) is the method of choice to study positive- and negative strand viral RNA synthesis during poliovirus replication. In comparison with other methods used for this purpose, it fulfils all necessary requirements to accurately determine RNA of different polarity. It combines high specificity, high sensitivity, safety, speed, and the ability to perform quantitative analysis. The enterovirus specific RT-PCR ELISA method described in this work, was used to determine quantitatively the amount of de novo poliovirus positive- and negative strand RNA synthesis at different time-points in the viral replication cycle, both in presence and absence of the viral RNA synthesis inhibitor guanidine hydrochloride.