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A N Maniatis

Publications and source records attributed to A N Maniatis.

At least 37 records · Page 2Linked to original sources
PubMed2003

Clinical isolates of macrolide-resistant Streptococcus pyogenes in Central Greece.

A total of 300 Streptococcus pyogenes isolates, collected during 2001 from five hospitals in the Thessalia district (Central Greece), were examined for their resistance to macrolides. Resistance to erythromycin was detected in 58 isolates (19.3%). Of these, 68.9% were susceptible to clindamycin (M-phenotype) and carried the mefA gene. Of the remaining isolates, 18 expressed the MLS(B) phenotype: 12 and six exhibited inducible and constitutive resistance to clindamycin, respectively. All of these strains were found to be ermA(TR) positive, except for four that had the ermB gene. Of the erythromycin-resistant strains, none was found to be resistant to penicillin, tetracycline or quinupristin-dalfopristin. Molecular typing by PFGE showed the presence of a limited number of clones.

Anti-Bacterial Agents↗
PubMed2003

Quick detection of Leishmania in peripheral blood by flow cytometry. Is prestorage leucodepletion necessary for leishmaniasis prevention in endemic areas?

Leishmaniasis is a serious health problem in various endemic areas. There are reports that the parasite can be transmitted via blood transfusions. We studied the clinical utility of flow cytometry for the screening of blood donors in an endemic area in Greece. Samples from 2000 blood donors from the area of Lasithi, Crete, Greece were examined by flow cytometry after labelling with a polyclonal anti-leishmania antibody conjugated with fluorescein-isothiocyanate derived from infected canines in the area. The same blood samples were simultaneously examined for serum anti-leishmania antibodies, May-Grünwald staining of peripheral blood smears and polymerase chain reaction (PCR) in buffy coat to the minicircle of kinetoplastic DNA. Direct sequencing of the PCR-amplified area helped discriminate leishmania species. Flow cytometry detected 33 cases with parasites in the peripheral blood leucocytes (1.65%), which were confirmed by PCR. One PCR-positive case was negative by flow cytometry. After prestorage leucodepletion, no sample was positive by PCR. Anti-leishmania antibodies were positive in 304 (15%) cases. Flow cytometry was found to be a sensitive and rapid method of detecting leishmania in peripheral blood samples. Leucodepletion effectively reduces the detection of the parasite, thus minimizing the potential risk of leishmania transmission through blood transfusions in endemic areas.

Adolescent↗
PubMed2003

Multiresistant Acinetobacter baumannii isolates in intensive care units in Greece.

One hundred and twenty-one clinical isolates of Acinetobacter baumannii recovered from the intensive care units (ICUs) of nine tertiary-care hospitals in Athens, Greece were studied in order to determine whether the increasing appearance of resistant acinetobacters is due to the spread of epidemic strains. The majority of the isolates exhibited resistance to ampicillin-sulbactam, and the most common antibiotic resistance profiles comprised resistance to nine and eight of the 11 potentially active antibiotics tested, respectively. Pulsed-field gel electrophoresis showed that 68% of the isolates, recovered from all ICUs, belonged to two clonal groups, indicating inter-hospital dissemination of multiresistant A. baumannii in our region.

Acinetobacter Infections↗
PubMed2003

Serum laminin and collagen IV in inflammatory bowel disease.

BACKGROUND: / AIMS: Laminin and collagen IV have been proposed as extracellular matrix serum markers. Because fibrosis is a major complication of inflammatory bowel disease, serum concentrations of laminin and collagen IV were measured in patients with ulcerative colitis (UC) and Crohn's disease (CD) and compared with inflammatory and healthy controls. METHODS: Laminin and collagen IV serum concentrations were measured in 170 patients with inflammatory bowel disease (86 UC and 84 CD), in 23 patients with other causes of intestinal inflammation, and in 80 matched healthy controls using commercially available enzyme linked immunosorbent assays. Laminin and collagen IV concentrations were correlated with disease activity, type, localisation, and treatment. RESULTS: Mean (SD) serum laminin concentrations were 281.0 (110.1) ng/ml in patients with UC, 275.6 (106.7) ng/ml in patients with CD, 192.0 (17.8) ng/ml in healthy controls, and 198.5 (32.5) ng/ml in inflammatory controls. Mean (SD) serum collagen IV concentrations were 72.8 (22.9) ng/ml in patients with UC, 71.0 (18.2) in patients with CD, 79.8 (12.2) ng/ml in healthy controls, and 88.9 (24.6) ng/ml in inflammatory controls. There was a significant difference among the four groups (p < 0.0001) for both markers. There was a strong correlation between serum laminin, but not collagen IV, and disease activity in both diseases. No significant association was found between these markers and disease localisation or disease type. CONCLUSIONS: Serum concentrations of laminin are increased, whereas serum concentrations of collagen IV are decreased, in patients with inflammatory bowel disease. They may be useful surrogate markers for sustained inflammation and tissue remodelling.

Adult↗
PubMed2002

Evaluation of an anti-PBP 2a slide latex agglutination test in coagulase-negative staphylococci isolated in Greek hospitals.

Oxacillin resistance was examined in 258 coagulase-negative staphylococci from Greek hospitals. mecA DNA was detected in 168 isolates, which were also resistant to oxacillin by agar dilution and disk diffusion, according to the current NCCLS breakpoints. Both methods exhibited a relatively low specificity misclassifying 21 and 19 of the 90 mecA-negative isolates respectively as oxacillin resistant. In contrast, an anti-PBP 2a latex agglutination test, applied after induction by oxacillin, correctly classified 163 mecA-positive (sensitivity 97%) and 88 mecA-negative isolates (specificity 97.7%).

Bacterial Proteins↗
PubMed2001

Methicillin-resistant Staphylococcus aureus in the hospitals of central Greece.

A total of 250 consecutive Staphylococcus aureus clinical isolates were collected during the period 1999-2000 from the five major hospitals of the district of Thessaly (Central Greece). Thirty seven (14.8%) of the isolates were mecA-positive (MRSA) in a PCR-based assay; all exhibited resistance to oxacillin (agar dilution MICs > or =4 mg/L) and were also resistant to multiple antibiotics. Most of the MRSA isolates had been collected in the intensive care units and the surgical wards of the participating hospitals in a sporadic fashion. The MRSA incidence found here was significantly lower than reported in previous studies from Greece. Molecular typing by PFGE showed that the MRSA isolates were distributed between three pulsotypes. Evaluation of various conventional methods for assessing methicillin resistance showed that oxacillin agar dilution and immunological detection of PBP2a with the Slidex MRSA Detection kit were the most reliable in this setting. Misclassifications of isolates exhibiting low-level resistance (oxacillin MIC 2-4 mg/L) occurred with the salt agar screen, the oxacillin disk diffusion and the ATB Staph System methods.

Bacterial Proteins↗
PubMed2001

Survey of methicillin-resistant coagulase-negative staphylococci in the hospitals of central Greece.

A sample of 450 consecutive, non-replicated coagulase-negative staphylococci (CoNS), collected from clinical specimens during the period 2000-2001 from the five major hospitals of Thessaly district (Central Greece) were investigated for resistance to methicillin. Most of the isolates had been collected in a sporadic fashion from the intensive care units and the surgical wards of the participating hospitals. The majority of the isolates (76%) were Staphylococcus epidermidis (50%), Staphylococcus haemolyticus (14.8%) and Staphylococcus hominis (11.1%). All 316 isolates (70%) were classified as resistant according to NCCLS breakpoints (MIC > or =0.5 mg/l); 268 (59.5%) of them were mecA-positive in a PCR-based assay. All isolates with MIC > or =8 mg/l carried the gene, while, only 23.8% of isolates with MIC, 0.5-4 mg/l were carriers. Only 9% of the mecA-positive isolates were found to be sensitive to various non-beta-lactams, while 41.8% of the isolates were resistant to more than three antimicrobial groups apart from beta-lactams. Molecular typing by PFGE showed apparent heterogeneity among isolates of each species and the absence of predominant clones.

Coagulase↗
PubMed2001

Predominance of a methicillin-resistant Staphylococcus aureus clone susceptible to erythromycin and several other non-beta-lactam antibiotics in a Greek hospital.

A clone of heterogeneously methicillin-resistant Staphylococcus aureus (MRSA) isolates susceptible to erythromycin, ciprofloxacin, clindamycin, co-trimoxazole, nitrofurantoin, rifampicin, tetracycline and vancomycin, predominated in a Greek hospital with a high incidence of MRSA, representing 69.1% of the total MRSA isolates. All isolates of this clone lacked the conserved genes ermA and aadD. Two subtypes of this clone were detected, the more common being resistant to aminoglycosides and carrying the bi-functional gene aacA-aphD, while an aminoglycoside-susceptible variant, lacking this gene, lost a larger SmaI macrorestriction DNA fragment and gained a smaller fragment.

Anti-Bacterial Agents↗
PubMed2001

Anti-Saccharomyces cerevisiae mannan antibodies and antineutrophil cytoplasmic autoantibodies in Greek patients with inflammatory bowel disease.

OBJECTIVES: The combined measurement of perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) and anti-Saccharomyces cerevisiae mannan antibodies (ASCA) has recently been suggested as a valuable diagnostic approach in inflammatory bowel disease (IBD). The aim of this study was to assess the value of detecting pANCA and ASCA in the differentiation between ulcerative colitis (UC) and Crohn's disease (CD) in a Greek population with IBD. METHODS: Sera were collected from 157 patients with IBD (97 with UC, 56 with CD, and four with indeterminate colitis) and 150 healthy controls. Determination of pANCA was performed by a standard indirect immunofluorescence technique on ethanol-fixed granulocytes and ASCA by an ELISA assay. RESULTS: In patients with UC, sensitivity, specificity, positive predictive value, and negative predictive value of the pANCA test was 67%, 84%, 93%, and 46% respectively. These values did not change significantly when the combination of positive pANCA and negative ASCA was used. ASCA test in diagnosing CD yielded a sensitivity, specificity, positive predictive value, and negative predictive value of 39%, 89%, 54%, and 81%. The combination of pANCA negative and ASCA positive increased the positive predictive value to 77% and it was associated with small bowel disease. CONCLUSIONS: A positive pANCA test in Greek patients has a diagnostic value in confirming a diagnosis of UC. Measurement of pANCA and ASCA together has a rather limited value in the differential diagnosis between UC and CD but may be of help in studying disease heterogeneity.

Adult↗
PubMed2001

Dissemination of clonally unrelated erythromycin- and glycopeptide-resistant Enterococcus faecium isolates in a tertiary Greek hospital.

Between September 1999 to February 2001, 25 glycopeptide-resistant Enterococcus faecium (GRE) isolates were recovered from a Greek hospital. The isolates exhibited 13 distinct chromosomal macrorestriction types by pulsed-field gel electrophoresis, and all were erythromycin and vancomycin resistant, carrying the genes vanA and ermB. Vancomycin resistance, always linked with erythromycin resistance, was transferable from 17 isolates. The dissemination of erythromycin-resistant GRE strains may, at least in part, reflect the extensive use of macrolides in husbandry in Greece.

Anti-Bacterial Agents↗
PubMed2001

Nosocomial spread of an unusual methicillin-resistant Staphylococcus aureus clone that is sensitive to all non-beta-lactam antibiotics, including tobramycin.

Between January and December 1999, in Hippokration General Hospital, Thessaloniki, Greece, a large proportion of the methicillin-resistant Staphylococcus aureus isolates (34.4%) exhibited susceptibility to virtually all alternative non-beta-lactam antibiotics, including tobramycin. Twenty-five of them were selected randomly for further testing; all belonged to a unique genotype and were characterized as heterogeneously resistant to oxacillin. The aadD gene, encoding tobramycin resistance, failed to be amplified in all cases, indicating absence of the gene or the entire plasmid pUB110 from the mec DNA.

Anti-Bacterial Agents↗
PubMed1999

Gradual increase in the minimum inhibitory concentration of penicillin among both susceptible and resistant Streptococcus pneumoniae isolates from Greek children during 1995-1997.

A total of 140 non-replicate Streptococcus pneumoniae community isolates from Greek children collected during the period 1995-1997 were studied. Combined intermediate and high penicillin resistance rates were 23% in 1995, 29% in 1996, and 27% in 1997. The proportion of highly resistant isolates steadily increased from 2% in 1995 to 12% in 1997. There was no significant difference in penicillin resistance rates among colonizing and infecting isolates (23 and 27%, respectively). Over the study period, a clear shift towards higher penicillin MIC was observed among both the susceptible and resistant groups. Thus, penicillin resistance rates were equally high among colonizing and infecting isolates and resistance levels appeared to be gradually increasing throughout the entire S. pneumoniae population.

Child↗
PubMed1999

A multi-centre study of nosocomial methicillin-resistant Staphylococcus aureus in Greece. Greek MRSA Study Group.

All 105 non-replicate consecutive Staphylococcus aureus strains isolated in 1997 from seven Greek hospitals, were found to be susceptible to vancomycin, teicoplanin and chloramphenicol, but only five (8%) were susceptible to all 16 antibiotics tested. Forty-three (41%) isolates were methicillin-resistant, 58% homogeneously (homMRSA) and 42% heterogeneously (hetMRSA). Resistance of homMRSA strains to other antibiotics was generally high (88-100%), although only one strain was resistant to netilmicin. Resistance in hetMRSA (6-39%) or in MSSA (5-11%) was significantly lower. Consequently, the majority (76%) of homMRSA were multi-drug resistant, while the dominant phenotype of hetMRSA and MSSA was resistance to penicillin (50% and 76%, respectively). Comparison of these strains with isolates from 1994 showed higher resistance rates to erythromycin among MSSA, to erythromycin and amikacin among hetMRSA and to rifampicin among homMRSA strains.

Anti-Bacterial Agents↗
PubMed1998

Emergence of multidrug resistance in ubiquitous and dominant Pseudomonas aeruginosa serogroup O:11. The Greek Pseudomonas Aeruginosa Study Group.

The serotypes of 88 nonreplicate nosocomial Pseudomonas aeruginosa isolates from 11 Greek hospitals were studied in relation to their antibiotic susceptibilities. Rates of resistance to beta-lactams, aminoglycosides, and quinolones ranged from 31 to 65%, except for those to ceftazidime (15%) and imipenem (21%). Four serotypes were dominant: O:12 (25% of isolates), O:1 (17%), O:11 (16%), and O:6 (10%). Multidrug resistance rates in the major serogroups O:12 (91%) and O:11 (79%) were higher than those in serogroups O:1 (40%) and O:6 (43%). Further typing with respect to pulsed-field gel electrophoresis patterns following XbaI digestion of genomic DNA discriminated the isolates into 74 types. Pulsed-field gel electrophoresis revealed that the ubiquitous O:12 group was genetically homogeneous, since 95% of strains belonged to two clusters of genotypic similarity, while the O:11 strains, present in 8 of the 11 hospitals, were distributed among five such clusters. Therefore, apart from the already reported O:12 multidrug-resistant European clone, an O:11 population, characterized by a serotype known to be dominant in the environment and the hospital in several parts of the world, but previously not associated with multidrug resistance to antibiotics, has progressed to a multidrug-resistant state.

DNA Fingerprinting↗
PubMed1996

Streptococcus agalactiae: a vaginal pathogen?

The significance of Streptococcus agalactiae as an aetiological agent in vaginitis was evaluated. A total of 6226 samples from women who presented with vaginal symptoms was examined. The presence of >10 leucocytes/high-power field (h.p.f.) was taken to be the criterion of active infection. S. agalactiae was isolated from 10.1% of these samples. The isolation rates of other common pathogens such as Candida spp., Gardnerella vaginalis and Trichomonas spp. were 54.1%, 27.2% and 4.2%, respectively, in the same group of patients. In contrast, the isolation rates of these micro-organisms in the group of patients who had no infection (<10 leucocytes/h.p.f.) were 4.2%, 38.3%, 33% and 0.5%, respectively. In the majority of samples from which S. agalactiae was isolated, it was the sole pathogen isolated (83%) and its presence was associated with an inflammatory response in 80% of patients. Furthermore, the relative risk of vaginal infection with S. agalactiae (2.38) in patients with purulent vaginal discharge was greater than that of Candida spp. infection (1.41) and lower than that of Trichomonas spp. infection (8.32). These data suggest that S. agalactiae in symptomatic women with microscopic evidence of inflammation should be considered a causative agent of vaginitis.

Adolescent↗
PubMed1995

Pseudomonas aeruginosa folliculitis due to non-O:11 serogroups: acquisition through use of contaminated synthetic sponges.

We describe the features of 13 cases of Pseudomonas aeruginosa folliculitis (eight of which occurred sporadically and five of which resulted from two family outbreaks) that developed subsequent to the use of commercial synthetic sponges for bathing. On the basis of O serogrouping and pyocin typing and subtyping, the strains recovered from the skin lesions were found to be identical to those isolated from household shower water and sponges. P. aeruginosa folliculitis is commonly caused by the serogroup O:11; The serogroups described in this study are rare causative agents of this type of skin infection. We believe that this is the first report of P. aeruginosa folliculitis due to serogroups O:3 and O:16.

Adult↗