Comparison of hepatitis C virus subtyping by ns5b sequencing with 5'utr based methods.

AIM: We compared Hepatitis C virus (HCV) genotyping by direct sequencing of the non-structural 5b region (NS5b) and a commercial PCR/hybridization method based on the conserved 5´-untranslated region (5'UTR). METHODS: One hundred twenty HCV containing plasma samples were analyzed by NS5b sequencing with focus on samples with undetermined results or 1b subtype identification in the used combination of Cobas® AmpliPrep/Cobas® TaqMan96® PCR and subsequent Versant® HCV Genotype 2.0 Assay (LiPA). RESULTS: There was 100% concordance between the two methods for genotyping but only 83% for subtyping. Seventeen samples were designated 1b by hybridization but subtype 1a by NS5b sequencing. This is a general 5'UTR problem as the discordant results were additionally confirmed by 5'UTR sequencing. Thus our routine combination not only misclassified 38.6% of subtype 1a isolates as 1b but in contrast to NS5b sequencing was unable to discriminate between subtypes 2a/c, or 4a/c/d and also failed on a newly described subtype (10a/3k). [corrected]. CONCLUSIONS: [corrected] The applied 5'UTR methods allow the rapid determination of HCV genotypes but failed to correctly identify the subtype in many samples. This has implications for epidemiological studies or forensic evaluation of chains of infection and NS5b sequencing therefore is our method of choice under those circumstances.

Nosocomial diarrhoea in adult medical patients: the role of Clostridium difficile in a North Italian acute care teaching hospital.

BACKGROUND: The number of patients with severe Clostridium difficile-associated diarrhoea (CDAD) increases. Health care facilities are requested to establish rates of nosocomially acquired CDAD (N-CDAD) to understand the impact of control or prevention measures, and the burden of N-CDAD on health care resources. OBJECTIVE: Aim of the single-center surveillance project was to establish local prevalence rates of N-CDAD in adult acute care medical patients. METHODS: For a period of at least one year, all diarrhoeal stools from inpatients of a general internal medicine ward were tested for Clostridium difficile toxin A. Case record files were retrospectively analysed and questionnaires were completed for patients with positive stool assays who met the case definitions. RESULTS AND DISCUSSION: During the surveillance period, 2,610 medical patients had been acutely hospitalized. Stools had been submitted to the hospital laboratory from 163 patients (6.2%) because of diarrhoea and were screened for Clostridium difficile cytotoxin. Complete data sets were available for analysis from 150 patients. Of 137 identified potential cases, 77 (56.2%) met the case definitions for nosocomial diarrhoea. Thirteen of the patients with nosocomial diarrhoea (16.9%) were detected positive by the Clostridium difficile toxin A assay. The overall prevalence of N-CDAD among inpatients was 8.7 cases/100 diarrhoeal stools. The mean number ofN-CDAD cases was 62.3 cases/100,000 patient days and 5 cases/1,000 patient admissions. The mean age of N-CDAD patients was 79.4 years (range 71 to 92). All patients were given broad-spectrum antibiotics before acute diarrhoea developed. Four patients died for reasons not directly related to N-CDAD which confirms increased disease severity as an important risk factor. CONCLUSIONS: This single-center surveillance project, which established N-CDAD rates at frequencies currently reported from international surveys, is useful as benchmark and will help in understanding patterns and impact of N-CDAD at the regional level.

Successful management of recurrent Epstein-Barr virus-associated multilocular leiomyosarcoma after cardiac transplantation.

BACKGROUND: In contrast to Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disorders (PTLD), EBV-associated leiomyomatous tumors have thus far only rarely been described. CASE REPORT: Two years after heart transplantation with ATG induction, cyclosporine (CsA; trough levels of 250 ng/mL)-based triple drug immunosuppression), a 23-year-old patient developed a small round lesion within the left lateral liver segment. The patient underwent ultrasound-guided biopsy followed by liver resection. Histological and immunohistological examination showed a leiomyosarcoma. In situ hybridization using EBV-specific EB endoplasmic reticulum-RNA showed an intensive signal in almost all tumor cells. The tumor stained for EB nuclear antigen (EBNA)-2-protein. Immunosuppression was drastically reduced, namely, CsA levels <100 ng/dL, prednisolone 5 mg, azathioprine withdrawn, and antiviral chemotherapy initiated with 10 days of IV gancyclovir and acyclovir followed by oral famcyclovir. During the follow-up, anti-EBV-IgM, anti-early antigen antibodies, and anti-EBNA antibodies were continuously monitored excluding significant EBV replication. Eighteen months post-liver resection, and high-resolution computed tomography scan demonstrated two paravertebral tumors. These lesions and a small nodule at the left ankle were resected revealing identical leiomyosarcomata. Immunosuppression was further reduced (CsA levels 75 ng/dL) and famcyclovir maintenance therapy started. Nevertheless, 2 years later the patient again developed tumor recurrence (perirectal, liver, and right adrenal gland); the tumors were surgically removed. The therapy was switched to Rapamycin and famcyclovir was continued. Three years after the last surgical intervention, the patient is well and recurrence-free. CONCLUSION: Long-term survival in patients with posttransplant EBV-associated leiomyosarcoma can be achieved by combined surgical intervention, reduction of immunosuppression, switch to Sirolimus, and antiviral chemotherapy.

Recombinant peptides derived from the env-gene of HIV-2 in the serodiagnosis of HIV-2 infections.

We produced recombinant envelope-derived peptides of HIV-2 for use in a diagnostic enzyme-linked immunosorbent assay (ELISA) or Western blot by expressing several restriction enzyme fragments from the env gene of HIV-2 in the bacterial fusion vector pEX-3. On Western blots, 17 out of 18 anti-HIV-2-positive sera available to us reacted strongly with those recombinant peptides which were derived from, or extended into, the transmembrane protein of HIV-2. In contrast, recombinant peptides derived from the external envelope glycoprotein were only weakly recognized by two sera. We observed a cross-reactivity of some human sera containing antibodies to HIV-1 with the HIV-2 peptides derived from the transmembrane protein of HIV-2. In spite of this cross-reactivity, a serological distinction between anti-sera to HIV-1 and HIV-2 can be attempted by simultaneous testing in ELISA on recombinant peptides derived from the transmembrane protein of HIV-1 and HIV-2.

Interaction of HSV-1 infected peripheral blood mononuclear cells with cultured dermal microvascular endothelial cells: a potential model for the pathogenesis of HSV-1 induced erythema multiforme.

The effect of herpes virus infection on human dermal microvascular endothelial cells and herpes-virus-1-infected peripheral blood mononuclear cells on human dermal microvascular endothelial cells was studied as a model of herpes-associated erythema multiforme. After infection of human dermal microvascular endothelial cells with native herpes virus and overnight culture, 60%--90% of human dermal microvascular endothelial cells showed cytopathic effects. HLA class I molecules and CD31 (PECAM-1) surface expression in herpes-virus-infected endothelial cells were substantially downregulated, whereas CD54 (ICAM-1) remained unchanged. Cocultivation with herpes-virus-1-infected peripheral blood mononuclear cells left characteristic plaques on the human dermal microvascular endothelial cell monolayer; however, very few human dermal microvascular endothelial cells (1%--3%) were infected. Adhesion molecule expression of human dermal microvascular endothelial cells cocultivated with herpes-virus-infected peripheral blood mononuclear cells demonstrated a 5-fold increase in CD54 expression, a 2-fold increase in HLA class I expression, but no change of CD31 by fluorescence-activated cell sorter analysis. Incubation of human dermal microvascular endothelial cells with ultraviolet-C irradiated herpes-virus-infected peripheral blood mononuclear cells had no effect on morphology or adhesion molecule expression levels. Changes of adhesion molecule expression by direct infection or cocultivation with peripheral blood mononuclear cells (with native and ultraviolet-C inactivated herpes virus infection) were also documented at the mRNA level. Adhesion assays demonstrated an increased binding of herpes-virus-infected peripheral blood mononuclear cells versus noninfected peripheral blood mononuclear cells to noninfected human dermal microvascular endothelial cells. Our results suggest that incubation of herpes-virus-infected peripheral blood mononuclear cells with human dermal microvascular endothelial cells induces significant upregulation of CD54 and major histocompatibility complex class I molecules in the surrounding noninfected human dermal microvascular endothelial cells, which is associated with an increased binding of peripheral blood mononuclear cells. Our in vitro findings may serve as a model for herpes-associated erythema multiforme possibly explaining the dermal inflammatory reaction seen in that condition.

Expression of the C3d/EBV receptor and of other cell membrane surface markers is altered upon HIV-1 infection of myeloid, T, and B cells.

Human cell lines (the T-cell lines H9, Jurkat, and HUT102, the myeloid lines U937 and HL60, and the Raji B cell line) were infected with HIV-1. HIV-1 antigen could be detected by immunofluorescence analysis in more than 50% of T cells and myeloid cells 15 days after infection. Infection of Raji cells took more than 2-3 months. Studies of cell surface marker expression revealed remarkable changes after HIV-1 infection of Raji cells: expression of CR2 (C3d/EBV receptor, CD19, CD20, CD22, CD23, CD10, and surface IgM) were highly reduced, in the case of CR2 and membrane-IgM from 100 to 0%, whereas levels of CD37 and CD38 remained unaltered by HIV-1 infection. U937 cells showed a reduction of CD4 expression from 14 to 5% after HIV-1 infection; the CR3 expression slightly increased from 25 to 30%. In contrast, HLA-DR was only expressed (21%) after HIV-1 infection but not in uninfected U937 cells. Expression of HLA-DR could be detected also in HL60 cells (33%) after HIV-1 infection. In H9 cells, CD4 was reduced from 60 to 30% after HIV-1 infection, whereas HLA-DR and CD25/IL-2 receptor expression increased from 16 to 90% and from 0 to 50%, respectively. CD4 was reduced from 70 to 0% from Jurkat cells after HIV-1 infection, whereas expression of CR2 was only slightly diminished from 8 to 4%. Expression of CR1 and HLA-DR was slightly increased in these cells (1 to 3%).(ABSTRACT TRUNCATED AT 250 WORDS)

Epstein-Barr virus-associated multicentric leiomyosarcoma in an adult patient after heart transplantation: case report and review of the literature.

Epstein-Barr virus (EBV)-associated smooth muscle tumors following solid organ transplantation are extremely rare, with only 12 cases reported in the literature thus far. The exact pathogenetic role of EBV infection in the oncogenesis of these soft tissue tumors in immunodeficient patients and the biologic behavior of such tumors is still unclear. We report a 26-year-old man in whom multiple smooth muscle tumors developed 36 to 51 months after heart transplantation. All tumors, two synchronous liver nodules, two subsequently occurring paravertebral tumors, and a single tumor in a vein at the left ankle were surgically resected. The tumor tissue was processed for routine histology and immunohistochemical (IHC) stains. Additionally, competitive polymerase-chain-reaction (PCR), reverse-transcriptase PCR (RT-PCR), as well as in situ hybridization (ISH) were used for EBV particle quantification and gene transcription analysis. The histologic features and immunohistochemical profiles were consistent with leiomyosarcoma in all tumor nodules. EBV infection was detected in >95% of tumor cell nuclei by EBER 1/2 ISH. Competitive PCR revealed 3105 EBV particles per milligram of tumor tissue. The EBV gene expression pattern analyzed by RT-PCR and IHC corresponded to the latency type III with specific expression of EBNA1, EBNA2, LMP1, and LMP2A genes. Under continuous antiviral therapy (famcyclovir) the patient currently shows no evidence of disease. Our data indicate that EBV infection plays a causal role in the development of smooth muscle tumors following organ transplantation. A latency type III, identical to EBV-associated posttransplant lymphoproliferative disorders, was identified and suggests a common pathogenetic mechanism in the development of these histogenetically distinct neoplasms. The fact that the patient currently shows no evidence of disease may be the result of the continuous administration of antiviral therapy because the soft tissue recurrences of the leiomyosarcoma occurred while the patient was not receiving antiviral prophylaxis.

Pseudorabies virus glycoprotein III derived from virions and infected cells binds to the third component of complement.

Glycoprotein III (gIII) of pseudorabies virus (PRV) was shown to bind to the third component of complement (C3). This was observed only with porcine C3 whereas human C3 showed negligible binding under the conditions tested. PRV virion proteins could be precipitated from supernatants and cell lysates of PRV-infected cells by means of swine-C3 coupled to sepharose. According to their molecular size and their reactivity with anti-gIII monoclonal antibodies, the precipitated PRV proteins represented the fully glycosylated and smaller forms of the gIII protein. Precipitation from PRV virions yielded predominantly the fully glycosylated form of gIII whereas infected cell lysates also contained lower molecular weight gIII proteins. The observed specificity of the virus protein for porcine C3 correlates well with the known host tropism of PRV. Our findings suggest that PRV gIII may exhibit more functions than solely providing attachment to heparin-like moieties on target cell surfaces. As the complement cascade is an important defense mechanism against a variety of pathogens, the interaction with the host C3, the pivotal component of the complement activation, might be a virulence factor of PRV.

Reduced CD21 (CR2) and CD54 (ICAM-1) expression in MT2 cells with HIV-1 or HIV-2 strains.

Alterations in the expression of cell-surface receptors have been reported in HIV-infected cells for CD4, CD25 (IL-2 receptor), CD2, CD3 and CD8 and CD26. In the present study we provide evidence that CD21 is down-regulated in the human T-lymphoblastoid cell line MT2 after infection with HIV-1 and -2 isolates. The same effect was observed with ICAM-1 (CD54). CD21 expression was monitored by means of fluorescence intensity, its functional ability to bind to C3d and by quantitative measurement of CD21-antigen in supernatants and cell lysates using an immunoassay. In addition, the decrease of CD21 and ICAM-1-specific mRNA suggests a mechanism at a transcriptional level. Our data suggest that HIV might have a direct influence on the receptor expression.

HIV and HIV-infected cells differentially activate the human complement system independent of antibody.

The human retroviruses HTLV-I and HIV-I have previously been shown not to be lysed by human serum. An interaction between HIV and the complement system, however, has not been investigated in any detail. In this report we show that purified HIV as well as HIV-infected cells activate the complement system. In the case of virus-infected cells this activation is mediated by the alternative pathway of complement, whereas the classical pathway seems to be in operation for the triggering of the complement system by purified virus and recombinant envelope glycoprotein (gp 160). We demonstrate that this leads to the deposition of C3b and/or C3bi on the surface of infected cells. But the HIV-infected cells are not lysed by human complement. C3 fragments deposited on the surface of HIV-infected cells are capable of mediating immune adherence to complement receptor-bearing cells, such as human erythrocytes and phagocytes. Whether this might have an influence on infectivity of HIV for certain cells bearing complement receptors has yet to be shown.

Macrophage tumor cell interaction is enhanced by C3 fragments.

We tested the capacity of Lewis Lung carcinoma cells (3LL) to activate the alternative pathway of complement and to bind the C3 fragments on the plasma membrane. C3 fragments were detected by cytofluorometry and by immunoblotting. In time, the fixed C3b molecules were further cleaved into iC3b. The presence of C3b/iC3b on the target enhanced the formation of conjugates with macrophages. In spite of increased contacts, macrophages from tumor bearing mice were not cytotoxic. Only preactivated macrophages, by in vivo treatment with Corynebacterium parvum, were shown to be cytotoxic; this function was potentiated when the target cells were opsonized with C3b/iC3b.

Selective induction of mononuclear phagocytes to produce neopterin by interferons.

Interferon-gamma (IFN-gamma) has been shown to be a potent inducer of neopterin secretion by human peripheral blood monocytes/macrophages (1). In this paper, it is shown that other known stimuli of monocytes (e.g., to secrete proteases or to migrate) such as zymosan-activated human serum, lipopolysaccharide, human C3/iC3 and zymosan coated with complement were unable to trigger monocytes/macrophages to release neopterin. Monocytes/macrophages could be stimulated solely by IFN-gamma (25 U/ml) and IFN-alpha at very high concentrations (10,000 U/ml). In the case of human peripheral blood mononuclear cells (PBMNC), basically the same pattern was observed. If however, in the buffer controls PBMNC showed some neopterin release, all stimuli triggered an increase of neopterin secretion: 10,000 U/ml IFN-alpha induced the same amount of secreted neopterin as did 25 U/ml of IFN-gamma. Both caused higher levels of neopterin secretion than ZAS, LPS and C3/iC3. Amongst the supernatants from PBMNC, only those which were obtained from cells activated with IFN-gamma or -alpha stimulated monocytes/macrophages to produce neopterin. Supernatants from lymphocytes activated with zymosan, lipopolysaccharide and interferon did not contain neopterin, nor did the latter induce monocytes/macrophages to generate and secrete neopterin. Antibodies against IFN-gamma inhibited the triggering effect of the supernatants except when generated by IFN-alpha at 10,000 U/ml. These results demonstrate that both interferons, IFN-gamma and IFN-alpha, the latter only at a 400-fold higher concentration, can trigger monocytes/macrophages directly to secrete neopterin. ZAS, LPS and C3/iC3 are weakly effective only on a mixture of lymphocytes and monocytes/macrophages, provided this cell mixture shows already a basic spontaneous neopterin release.(ABSTRACT TRUNCATED AT 250 WORDS)

Activity of N-chlorotaurine against herpes simplex- and adenoviruses.

N-chlorotaurine, an essential weak oxidant produced by stimulated human leukocytes, is known to have bactericidal, fungicidal and vermicidal properties. This study for the first time demonstrates its virucidal activity. By viral suspension tests at incubation times between 5 and 60 min, virus titers of both Herpes simplex virus type 1 and 2 were reduced about 1.3-2.9 log10 and 2.8-4.2 log10 by 0.1 and 1%, (5.5 and 55 mM) N-chlorotaurine, respectively. Virus titer reduction of adenovirus type 5 between 15 and 60 min was 0.5-2.0 and 0.6-4.0 log10, respectively, by the same concentrations of N-chlorotaurine. These findings support a contribution of N-chlorotaurine in destruction of pathogens during inflammatory reactions and also the possibility of its application as an antiviral agent in human medicine.

[Human herpesvirus 6 (HHV-6): incidence in healthy blood donors and in patients with acute infections caused by other herpes viruses]. / Humanes Herpesvirus 6 (HHV-6): Vorkommen bei gesunden Blutspendern und in Patienten mit akuten Infektionen durch andere Herpesviren.

Antibodies to HHV-6 were detected by immunofluorescence in 8.04% of 460 healthy blood donors in West Austria. Testing sera from patients with acute or reactivated infections with other herpesviruses, such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) and varicella zoster virus (VZV) we observed a remarkably higher prevalence of antibodies to HHV-6 in patients with CMV infections (75%) and also in patients with EBV infections (50%). Patients with HSV and VZV infections were positive for HHV 6 in 12.5% and 6.6% of cases, respectively. Many of the patients with CMV infection were transplant recipients. The high incidence of positive HH 6 serology in these patients could be due to new infection by HHV 6 or to the reactivation of a previous infection with HHV 6 by means of allogenic cell stimulation. Furthermore, preliminary results from our laboratory point to a serological cross-reaction between HHV 6 and CMV, which may also contribute to this result.

[Detection of antibodies to HTLV-III: a comparison of various ELISA methods as screening tests and the Western Blot with immunofluorescence as confirmatory procedures]. / Nachweis von Antikörpern gegen HTLV-III: Vergleich verschiedener ELISAs als Suchtests und des Western Blot mit der Immunfluoreszenz. Bestätigungsverfahren.

386 sera were examined with three commercially available ELISAs for antibodies to HTLV-III. Western Blot and an indirect immunofluorescence assay were performed on sera showing a positive reaction in one or more ELISAs as confirmatory assay. 299 sera reacted negatively in all ELISAs, 48 were positive in all ELISAs and the confirmatory assays, whilst 33 ELISA positive sera reacted negatively in the confirmatory assays. In the case of 5 sera both Western Blot as well as the immunofluorescence assay had to be undertaken to obtain conclusive results.

[Specific serologic studies with a novel authentic HPV antigen (virus-like particles) for HPV-6 antibodies in gynecologic patient samples]. / Spezifische serologische Untersuchungen mit einem neuartigen authentischen HPV-Antigen (Virus-like Particles) auf HPV-6 Antikörper bei gynäkologischen Patientenkollektiven.

OBJECTIVE: A serological assay for genital HPV infection would provide important additional information to HPV DNA diagnostic methods, since it would evaluate prior exposure to the viruses, detect significant systemic immunologic response to virus infection, and could be performed in most clinical laboratories. METHODS: Serum samples from three groups of patients attending a gynecology clinic were analysed by direct ELISA for specific IgG antibodies to baculovirus-expressed HPV-6 and BPV-1-L1-VLPs. RESULTS: Positive IgG reactivity to HPV-6-L1-VLPs were 4/72 (6%) in a control group, 28/73 (38%) in a condyloma group and 17/62 (17%) in cervical intraepithelial neoplasia patients. Individual IgG ELISA values of condyloma and CIN patients for HPV-6-L1-VLPs demonstrated no correlation to results with BPV-1-L1-VLPs. CONCLUSIONS: These data show that HPV-6-L1-VLPs are effective antigens for serological studies and can detect species specific antibodies with important implications for diagnosis, epidemiology, insights to natural course of disease, prognosis and evaluation of vaccination.

[The choice of a pediatric anesthesia ventilator]. / Comment choisir un respirateur d'anesthésie pédiatrique?

The technology of anesthesia ventilators has substantially progressed during last years. The choice of a pediatric anesthesia ventilator needs to be led by multiple parameters: requirement, technical (pneumatic performance, velocity of halogenated or oxygen delivery), cost (purchase, in operation, preventive and curative maintenance), reliability, ergonomy, upgradability, and compatibility. The demonstration of the interest of pressure support mode during maintenance of spontaneous ventilation anesthesia makes this mode essential in pediatrics. In contrast, the financial impact of target controlled inhalation of halogenated has not be studied in pediatrics. Paradoxically, complex and various available technologies had not been much prospectively studied. Anesthesia ventilators performances in pediatrics need to be clarified in further clinical and bench test studies.

Metallo-ß-lactamases among Enterobacteriaceae from routine samples in an Italian tertiary-care hospital and long-term care facilities during 2008.

The emergence of metallo-ß-lactamase (MBL)-producing Enterobacteriaceae is a serious public health concern. Producers have been repeatedly isolated from patients and long-term care facility (LTCF) residents around Bolzano, and we sought to assess their prevalence and clinical impact. All routine Enterobacteriaceae isolates from a Bolzano tertiary-care hospital and associated long-term care facilities in 2008 (n = 5500) were screened for MBLs, with case details reviewed for the source patients. In total, 36 producers were obtained from 29 patients, comprising 14 Escherichia coli, six Klebsiella pneumoniae, four Klebsiella oxytoca, four Citrobacter freundii, two Enterobacter cloacae and two Morganella morganii, as well as single Citrobacter amalonaticus, Enterobacter aerogenes, Providencia stuartii and Proteus mirabilis isolates. All were PCR-positive for bla(VIM) and 25 were PCR-positive for qnrS; 19 non-K. pneumoniae had bla(SHV) and one had bla(CTX-M-group1); 13 were from 12 LTCF residents and 23 were from 17 acute-care patients. All these patients had serious underlying diseases with prolonged hospitalization or LTCF stay; only seven had infections due to the MBL producers, comprising four urinary tract infections, two catheter-related bloodstream infections and one patient with both a surgical site infection and pneumonia. Five patients had more than one MBL-producing organism. Pulsed-field gel electrophoresis identified a cluster of six related E. coli, whereas pairs of K. pneumoniae and C. freundii isolates had >85% profile similarity. Transformants prepared from two isolates were shown to be PCR-positive for bla(VIM), qnrS and bla(SHV); their plasmids gave similar restriction fragment length polymorphism patterns, and bla(VIM-1), qnrS1 and bla(SHV-12) were detected by sequencing.

Colonization of residents and staff of a long-term-care facility and adjacent acute-care hospital geriatric unit by multiresistant bacteria.

Long-term-care facilities (LTCFs) are reservoirs of resistant bacteria. We undertook a point-prevalence survey and risk factor analysis for specific resistance types among residents and staff of a Bolzano LTCF and among geriatric unit patients in the associated acute-care hospital. Urine samples and rectal, inguinal, oropharyngeal and nasal swabs were plated on chromogenic agar; isolates were typed by pulsed-field gel electrophoresis; resistance genes and links to insertion sequences were sought by PCR; plasmids were analysed by PCR, restriction fragment length polymorphism and incompatibility grouping. Demographic data were collected. Of the LTCF residents, 74.8% were colonized with ≥1 resistant organism, 64% with extended-spectrum ß-lactamase (ESBL) producers, 38.7% with methicillin-resistant Staphylococcus aureus (MRSA), 6.3% with metallo-ß-lactamase (MBL) producers, and 2.7% with vancomycin-resistant enterococci. Corresponding rates for LTCF staff were 27.5%, 14.5%, 14.5%, 1.5% and 0%, respectively. Colonization frequencies for geriatric unit patients were lower than for those in the LTCF. Both clonal spread and plasmid transfer were implicated in the dissemination of MBL producers that harboured IncN plasmids bearing bla(VIM-1), qnrS, and bla(SHV-12). Most (44/45) ESBL-producing Escherichia coli isolates had bla(CTX-M) genes of group 1; a few had bla(CTX-M) genes of group 9 or bla(SHV-5); those with bla(CTX-M-15) or bla(SHV-5) were clonal. Risk factors for colonization of LTCF residents with resistant bacteria included age ≥86 years, antibiotic treatment in the previous 3 months, indwelling devices, chronic obstructive pulmonary disease, physical disability, and the particular LTCF unit; those for geriatric unit patients were age and dementia. In conclusion, ESBL-producing and MBL-producing Enterobacteriaceae and MRSA were prevalent among the LTCF residents and staff, but less so in the hospital geriatric unit. Education of LTCF employees and better infection control are proposed to minimize the spread of resistant bacteria in the facility.