Molecular characterization of Mycobacterium tuberculosis isolates presenting various drug susceptibility from Greece using three DNA typing methods.

Objectives: The purpose of the present study was the molecular characterization of Mycobacterium tuberculosis clinical isolates using three DNA typing methods.

Methods: One hundred nineteen independent (77 susceptible to all antituberculous drugs, 17 rifampin-resistant and 25 isoniazid-resistant), and nine related Mycobacterium tuberculosis isolates obtained over a 3-years period (1997-1999) from Greece were typed with restriction fragment length polymorphism (RFLP), using the non-radioactive IS6110 probe (IS6110-RFLP), and two PCR-based molecular methods: random amplification of polymorphic domains (RAPD) using four different primers and double repetitive element-PCR (DRE-PCR).

Results: IS6110-RFLP and RAPD-PCR using IRIS primer were proved to be the most discriminatory methods, while DRE-PCR gave satisfactory results and RAPD-PCR methods using the other three primers (A1245, B1245 and Leg2) were not so effective.

Brachyspira (Serpulina) pilosicoli spirochetemia in an immunocompromised patient.

The case of an elderly immunocompromised man with non-Hodgkin's lymphoma who presented with fever, abdominal pain and bloody diarrhea is described. Brachyspira pilosicoli was isolated from culture. The patient was treated with penicillin G i.

Molecular typing of Candida isolates from patients hospitalized in an intensive care unit.

Objectives: The aim of our study was the molecular typing of 40 clinical isolates of Candida spp. obtained from patients with burns or trauma hospitalized in the intensive care unit of a general hospital.

Methods: Isolates were recovered from blood, deep trauma, urine, sputum or from environment within a short period of time (4 months).

Comparison of Mycobacterium avium isolates from Greek AIDS and human immunodeficiency virus-negative patients by pulsed-field gel electrophoresis.

Objective: To compare the chromosomal types of Mycobacterium avium strains infecting HIV-negative and AIDS patients in Greece.

Methods: In total, 41 Mycobacterium avium isolates, 23 from AIDS and 18 from HIV-negative patients, were compared by pulsed-field gel electrophoresis of genomic DNA after XbaI digestion. The majority (87%) of AIDS isolates were from disseminated infection, while the majority (61%) of HIV-negative isolates were from children with cervical lymphadenitis.

Human immunodeficiency virus (HIV) protease inhibitors have no effect on hepatitis C virus (HCV) serum levels of HIV-HCV co-infected patients.

Ten severely immunocompromised HIV-HCV co-infected patients were enrolled in a quantifiable HCV-RNA assay. Serum alanine aminotransferase, HCV-RNA levels and HIV viral loads were determined at baseline, at month three and at month six after initiation of a highly active antiretroviral therapy including an HIV protease inhibitor. HCV genotypes were determined using a line probe assay kit.

Mycobacterium genavense infection in normal and immunodeficient mice.

Mycobacterium genavense is a recently described microorganism causing disseminated infections in AIDS patients. In this study, we investigate its pathogenicity in mice and some mechanisms of the host response to this bacterium. Following an intravenous challenge of 10(6) organisms, M.

Comparison of clarithromycin-sensitive and clarithromycin-resistant Mycobacterium avium strains isolated from AIDS patients during therapy regimens including clarithromycin.

Objectives: Sixteen Mycobacterium avium strains were isolated from the blood of eight AIDS patients over a period of months. All the patients were on combination therapies including clarithromycin, and all had treatment failure and relapses of M.avium bacteremia.

Molecular typing of Legionella pneumophila serogroup 1 isolates from patients and the nosocomial environment by arbitrarily primed PCR and pulsed-field gel electrophoresis.

The ubiquity of Legionella pneumophila in aquatic habitats means that epidemiological evaluation is important for the investigation and control of nosocomial outbreaks of legionellosis. Pulsed-field gel electrophoresis (PFGE) of chromosomal DNA following digestion with SfiI is considered to be one of the most discriminative methods for detecting DNA polymorphisms amongst L. pneumophila serogroup 1 (Lp1) isolates.

Single clonal origin of a high proportion of Legionella pneumophila serogroup 1 isolates from patients and the environment in the area of Paris, France, over a 10-year period.

Arbitrarily primed PCR with three primers and pulsed-field gel electrophoresis were used to characterize a set of 75 clinical Legionella pneumophila serogroup 1 isolates, with no apparent epidemiological link, obtained from 24 hospitals in Paris, France, from 1987 to 1997. Unexpectedly, 25 clinical isolates from 15 hospitals had an identical profile (termed type A) by both methods. The same profile was subsequently found in 16 of 64 randomly selected environmental L.

Isolation of a specific DNA fragment and development of a PCR-based method for the detection of Mycobacterium genavense.

The rise of Mycobacterium genavense infections is making identification ever more important for diagnosis and treatment. Moreover, isolation and identification of M. genavense are made difficult by the lack of growth on solid media and by its low generation rate in BACTEC liquid media.

Treatment of disseminated Mycobacterium genavense infection in a murine model with ciprofloxacin, amikacin, ethambutol, clarithromycin and rifabutin.

Mycobacterium genavense is a recently described agent which can induce disseminated infections in patients with AIDS. Up to now, no standard approach to treatment has been defined and patients have been treated empirically with antibiotics used for treating infections caused by other nontuberculous mycobacteria. In this study, we compared the effectiveness of ciprofloxacin, amikacin, ethambutol, clarithromycin and rifabutin in the treatment of an animal model of M.

Molecular markers for the investigation of Mycobacterium gordonae epidemics.

Mycobacterium gordonae was isolated as a light growth from bronchoalveolar aspirates from nine patients over 12 months. All patients were in one hospital, and had been bronchoscoped for suspected malignancy. None of the patients had symptoms or radiographic findings of mycobacterial infection.

Characterization of rpoB mutations in rifampin-resistant clinical Mycobacterium tuberculosis isolates from Greece.

There is a geographic distribution of Mycobacterium tuberculosis strains with various rpoB gene mutations that account for rifampin resistance. We studied 17 rifampin-resistant clinical isolates from patients in Greece to identify rpoB mutations. The aim of our study was the evaluation of a commercially available line probe assay kit (INNO-LiPA Rif.

Characterization to species level of Mycobacterium avium complex strains from human immunodeficiency virus-positive and -negative patients.

Forty human clinical Mycobacterium avium-M. intracellulare complex strains isolated in Greece were characterized to the species level by PCR with three sets of primers specific for one or both species. M.

T-cell response during Rhodococcus equi infection in a murine experimental model.

Rhodococcus equi is a facultative intracellular bacterium that can cause pneumonia in both young horses and immunocompromised humans. In this study, we have tried to determine the T-cell populations that recognize this pathogen during murine infection, as well as the bacterial antigens recognized by these cells. When BALB/c mice were hyperimmunized with a virulent R.

Lack of resistance to erythromycin, rifampicin and ciprofloxacin in 98 clinical isolates of Legionella pneumophila.

Ninety-eight consecutive clinical isolates of Legionella pneumophila were tested for erythromycin, rifampicin and ciprofloxacin susceptibility. MICs, determined by agar dilution testing, were in the range 0.06-1 mg/L of erythromycin, 0.

Rapid discrimination of Mycobacterium avium strains from AIDS patients by randomly amplified polymorphic DNA analysis.

A randomly amplified polymorphic DNA (RAPD) analysis was performed for the molecular typing of Mycobacterium avium strains. This method was applied to epidemiologically unrelated M. avium strains isolated from the blood of 10 different AIDS patients and to strains that were considered epidemiologically related, as they had been isolated from the same patient but from different body locations (4 patients, 10 strains).

JC virus detection in the cerebrospinal fluid of AIDS patients with progressive multifocal leucoencephalopathy and monitoring of the antiviral treatment by a PCR method.

Twenty-four cerebrospinal fluid (CSF) samples from 19 AIDS patients with neurological signs were analysed by the polymerase chain reaction (PCR) for the presence of JC virus (JCV). Eleven of the 19 patients tested presented with progressive multifocal leucoencephalopathy (PML). Two specific JCV target sequences were used for the PCR analysis: a sequence specific for the T antigen genes from both BK virus (BKV) and JCV (PCR1) and a sequence specific for the large T antigen gene from JCV (PCR2).

[Legionnaires' disease in the Paris area: epidemiology and mortality. Apropos of a series of 81 culture-positive cases].

Objectives: Evaluate etiological circumstances and prognosis in Legionnaires' disease.

Methods: A series of 81 culture-proven cases of Legionnaires' disease was collected in the Paris area between 1989 and 1994.

Results: Direct immunofluorescence assay was positive for Legionella pneumophilia in 48% of the cases.

Beneficial effect of Salmonella typhimurium infection and of immunoglobulins from S. typhimurium-infected mice on the autoimmune disease of (NZB x NZW) F1 mice.

Various infections can precede or aggravate autoimmune diseases. Yet a beneficial effect of infection has also been described an various mechanisms have been postulated to explain this effect. The aim of this study was to examine the hypothesis that infection can have an immunoregulatory effect on the autoimmune process via the increased production of natural polyreactive antibodies.

Gamma interferon and interleukin-10 gene expression in innately susceptible and resistant mice during the early phase of Salmonella typhimurium infection.

Previous studies have shown that gamma interferon (IFN-gamma) plays a major role in natural resistance to Salmonella typhimurium during the early phase of infection. To assess whether the level of natural resistance in mice is related to the level of IFN-gamma gene expression, we compared IFN-gamma mRNA levels by means of reverse transcriptase-PCR in the spleens of genetically susceptible Itys (C57BL/6 and BALB/c) and resistant Ityr (CBA and DBA/2) mice during the first 5 days of infection. The mRNA expression of interleukin-10 (IL-10), a cytokine which antagonizes IFN-gamma effects, was also investigated.