High level of resistance to metronidazole and clarithromycin in Helicobacter pylori isolated from pediatric patients in Poland (1997-2001).

Resistance to metronidazole (Met), clarithromycin (Cla) and amoxycillin (Amo) was examined using H. pylori isolates from child patients before and after treatment in the period 1997-2001. The rate of Met and Cla resistance before treatment was 35.2 and 8.6%, respectively. Six weeks after treatment 48.4% of the isolated strains were resistant to Met and 17.6% to Cla. The highest rate of resistance to both antibiotics was determined in 2001 (before treatment, 46 and 15%, respectively, and after treatment, 57.8 and 26.3%, respectively). All the strains were susceptible to Amo. Strains resistant to Met were detected more frequently in girls than in boys.

Neutralisation of cytotoxic vacuolating activity by serum antibodies of Helicobacter pylori-infected patients.

The study involved 196 H. pylori strains and 196 serum samples taken from the same patients. H. pylori strains were investigated for the production of vacuolating cytotoxin. Antibodies to the vacuolating cytotoxin produced by H. pylori were detected in the sera samples by neutralisation assay (on Intestine 407 cells) and ELISA. Of the 196 H. pylori strains tested, 80 (40.8%) were found to express vacuolating cytotoxic activity. The titres of cytotoxic nonconcentrated broth culture filtrates ranged from 1:2 to 1:128. The vacuolating assay was positive in 37.1% strains isolated from children, and in 50% strains isolated from adults. Cytotoxin-positive H. pylori strains were found more frequently in duodenal ulcer (71%) than in chronic gastritis (35.2%) patients, and this difference was statistically significant p < 0.05. Neutralising antibodies to vacuolating cytotoxin were present in 51% and 49% of the serum samples tested by neutralisation and ELISA, respectively. Duodenal ulcer patients had antibodies to vacuolating cytotoxin more frequently (p < 0.05) than chronic gastritis patients. Antibodies to cytotoxin were detected in the serum samples from patients infected by cytotoxic (100%) and noncytotoxic (18%) H. pylori strains.

[Antagonistic activity of Lactobacillus bacteria strains against anaerobic gastrointestinal tract pathogens (Helicobacter pylori, Campylobacter coli, Campylobacter jejuni, Clostridium difficile)]. / Antagonistyczne dzialanie bakterii z rodzaju Lactobacillus wobec beztlenowych i mikroaerofilnych czynników zakazen przewodu pokarmowego (Helicobacter pylori, Campylobacter coli, Campylobacter jejuni, Clostridium difficile).

Antagonistic activity of Lactobacillus strains has been known for some time. This property is connected with production of many active substances by lactobacilli e.g., organic acids and bacteriocin-like substances which interfere with other indigenous microorganisms inhabiting the same ecological niche, including also anaerobic gastrointestinal tract pathogens. Growing interest of clinical medicine in finding new approaches to treatment and prevention of common inflammatory infections of the digestive tract resulted in studies on a possible usage of lactic acid bacteria. Last years, several in vitro and in vivo experiments on antagonism of different Lactobacillus strains against Helicobacter pylori and Clostridium difficile were performed. These observations had been done on already established, well known probiotic Lactobacillus strains. We tested antibacterial activities of Lactobacillus strains isolated from human digestive tract. As indicator bacteria, four species known as anaerobic bacterial etiologic agents of gastroenteric infections: Helicobacter pylori, Campylobacter jejuni, C. coli and Clostridium difficile were used. Some of them were obtained from international collections, others were clinical isolates from specimens taken from patients with different defined gastrointestinal infections. We used a slab method of testing inhibitory activity described in details previously. Following conclusions were drawn from our study: All tested human Lactobacillus strains were able to inhibit the growth of all strains of anaerobic human gastrointestinal pathogens used in this study. Inhibitory activities of tested Lactobacillus strains against Helicobacter pylori, Campylobacter spp., and Clostridium difficile as measured by comparing mean diameters of the inhibition zones were similar. Differences in susceptibility of individual indicator strains of Campylobacter spp. and Clostridium difficile to inhibitory activity of Lactobacillus strains were small. A similar mechanism of inhibition of anaerobic bacteria by lactobacilli is postulated.

[Surface properties of Lactobacillus strains. I. Hemagglutination and hydrophobicity]. / Wlasciwosci powierzchniowe bakterii z rodzaju Lactobacillus. I. Wlasciwosci hemaglutynacyjne i hydrofobowe.

Bacteria possess many surface membrane properties, both mechanical and biochemical, that allow them to interact with their environment These properties may affect a host in either positive (beneficial) or negative (pathological) ways. All surface properties of bacteria are yet unknown therefore we attempt to increase our knowledge regarding specific strains of lactobacilli, by examining the known properties including hemagglutination and hydrophobicity. The purpose of this study was to evaluate the cell surface properties of certain strains of Lactobacillus. These strains isolated from the human vagina and gastrointestinal tract were selected because of their antagonism toward aerobic and anaerobic bacterial pathogens. Part I discusses the hydrophobicity and hemagglutination abilities of these Lactobacillus strains.

[Surface properties of Lactobacillus strains. II. Adherence to tissue culture surfaces]. / Wlasciwosci powierzchniowe bakterii z rodzaju Lactobacillus. II. Adherencja do linii komórkowych.

In the second part of this study, we evaluated the adherence properties of specific strains of Lactobacillus isolated from both the human vagina and gastrointestinal tracts. Lactobacilli taken from the vagina and GI tract were tested for their adherence to A431 vaginal tissue, and to CaCo-2 cells taken from the gastrointestinal tract. The Lactobacillus strains with the most marked adherence to the respective cell lines were examined under the electron microscope. These images revealed the presence of a substance morphologically resembling slime, which probably possess unknown active properties.

Neutralisation of vacuolating activity of cytotoxin by serum antibodies of Helicobacter pylori infected patients.

The study involved 196 H. pylori strains and 196 serum samples taken from the same patients. H. pylori strains were investigated for the production of vacuolating cytotoxin. Antibodies to the vacuolating cytotoxin produced by H. pylori were detected in the sera samples by neutralisation assay (on Intestine 407 cells) and ELISA. Of the 196 H. pylori strains tested, 80 (40.8%) were found to express vacuolating cytotoxic activity. The titres of vacuolating cytotoxic were ranged from 1:2 to 1:128. The vacuolating assay was positive in 37.1% strains isolated from children, and in 50% strains isolated from adults. Cytotoxin-positive H. pylori strains were found more frequently in duodenal ulcer (71%) than in chronic gastritis (35.2%) patients, and this difference was statistically significant p<0.05. Neutralising antibodies to vacuolating cytotoxin were present in 51% and 49% of the serum samples tested by neutralisation and ELISA, respectively. Duodenal ulcer patients had antibodies to vacuolating cytotoxin more frequently (p<0.05) than chronic gastritis patients. Antibodies to cytotoxin were detected in 100% of the serum samples from patients infected by cytotoxic H. pylori strains. This suggests that the presence of anticytotoxic antibodies in the serum samples may be regarded as a sensitive indicator of infection by cytotoxic H. pylori strains.

[Evaluation of bacteriological research data and laboratory symptoms of infection in the diagnosis of congenital and acquired infections]. / Ocena wyników badán bakteriologicznych oraz laboratoryjnych wykladników infekcji w rozpoznawaniu zakazen wrodzonych oraz nabytych.

The predisposition of the newborns to contract infections diseases is dependent upon the limited efficiency of their immune mechanisms. Congenital infections amount to 5.7% in the research material, and the acquired infections 1.15%. The isolation of the microorganism is the basis for treating infections-the profiles of the pathogenic bacterial in flora were subjected to analysis. Im generalised infections Stafphylococcus epidermidis makes 56.6% and E. Coli accounts for 87.5 of the infections of the urinary system. In our research the late sepsis and pneumonia are more frequently the result of the hospital infection (14.2%) in the cases of congenital infections-pneumonia and the infection of the urinary system (72%). Hematologic indicators such as: leucopenia, thormbocytopenia, I/T are distinct infection markers (those were found in 31% of the cases). The CRP protein shows the lowest values in congenital infections, still monitoring its level is useful for assessing the effectiveness of the undertaken antybacterial treatment. The newborns of male sex (58%) more often prone to infection. Pneumonia is the manifestation pertaining to an organ in 70% of congenital infections, the infection of urinary system amounts to 17.1%.

[Adhesins of Acinetobacter strains]. / Adhezyny paleczek z rodzaju Acinetobacter.

One of the important factors contributing to the pathogenicity of bacteria is the presence of adhesins on cell surface, which facilitate colonisation in the macroorganism. The presence and type of adhesins occurring in four species of the genus Acinetobacter: A. baumannii (184), A. junii (59), A. lwoffii (65) and A. haemolyticus (22) was determined by haemagglutination test with a 3% suspension of fresh, tannic acid-treated of guinea pig, cow and human group O and AB erythrocytes, with or without the addition of one of sugar inhibitors (D-mannose, alpha-methylmannopyranoside, D-galactose-N-acetyl-D-glucosamine, L-fucose and D-ribose). In strains from all species, adhesines of the mannose-resistant (MR) type dominated. The mannose-sensitive (MS) type was present solely on the surface of one A. lwoffii strains. A. baumannii (36), A. junii (8), A. lwoffii (11) and A. haemolyticus (4) exhibited mannose-resistant hemagglutination in relation to fresh erythrocytes and that reaction was restrained by D-galactose, D-galactose and L-fucose (no other inhibitor used restrained it). The results achieved prove that cell adhesines other than those of MR type must be present on the cell surface. Additional adhesines occurred mainly in strains isolated from the respiratory and urinary tract infection simples, but were not found in isolates from blood cultures.

Relationship between antibody to cytotoxin and Helicobacter pylori infection.

Broth culture supernatants from 14 (34%) out of the 41 H. pylori strains tested, induced vacuolization in Intestine 407 cells in titers ranging from 1:2 to 1:64. 20% of H. pylori strains isolated from children and 42% of strains isolated from adults expressed vacuolating activity. Serum antibody to cytotoxin produced by H. pylori was detected with a neutralization assay. Anticytotoxic antibodies were present in all sera from patients infected with cytotoxic H. pylori strains. The toxin-neutralizing activity of sera from individuals infected with H. pylori suggests that the cytotoxin is produced in vivo.

Helicobacter pylori in kidney allograft recipients: high prevalence of colonization and low incidence of active inflammatory lesions.

Since kidney transplant recipients are at enhanced risk for developing severe upper gastrointestinal disease and Helicobacter pylori (Hp) is an important pathogen in active gastritis and peptic ulcer, we performed gastroduodenoscopic examination, coupled with assessment of Hp colonization in 29 renal allograft recipients complaining of recurrent dyspepsia. Results were compared with those of 25 chronically hemodialyzed patients and 16 subjects free from renal disease, also suffering from upper gastrointestinal symptoms of similar severity. We found that while transplant recipients have had a high prevalence of Hp infection (62 vs. 34.6% in dialysis and 43.6% in control dyspeptic patients), active gastritis was clearly less frequently seen in these patients than in control subjects (transplant group: 6.9%, dialysis 3.8%, control 31.3%) and peptic ulceration was totally absent. Prevalence of Hp colonization was even higher in renal graft recipients on triple posttransplant immunosuppression (82%). In dyspeptic transplant and dialysis patients, colonization with Hp did not account for development of active inflammatory lesions, an association frequently seen in subjects free from renal disease and immunosuppressive therapy.

Helicobacter pylori infection in Eastern Europe: seroprevalence in the Polish population of Lower Silesia.

The Helicobacter pylori status of the population of Eastern European countries has not been explored despite the high incidence of peptic ulcer disease and gastric cancer observed in these countries. A seroprevalence study has been performed in Wroclaw, a city of Lower Silesia, Poland, to provide insight into this question. Sera were collected to obtain 50 subjects per 5 yr increment of age. A second generation ELISA kit with a high sensitivity and specificity was used. The results plotted by year of birth show a very high prevalence of H. pylori infection in all adults groups born before 1970 (80-100% positive). In the younger age groups, a dramatic decrease was observed. Because it is now known that most H. pylori infections are acquired in childhood (cohort effect), it can be predicted that the infection rate in the adult population will be much lower in the future compared with that presently observed, and it can be expected that evolution in H. pylori prevalence will have an impact on the rate of gastroduodenal diseases in Poland. Because of the high prevalence, it was not possible to identify risk factors for infection in this population.

Adhesive properties of P-like fimbriae in Klebsiella-species.

Clinical isolates of three encapsulated Klebsiella strains with type 1 (mannose-sensitive, MS+MR-), type 3 (mannose-resistant, MS-MR+), type 1.3 (MS+MR+) fimbriae and facultatively coexpressing P-like fimbria were investigated for their ability to adhere to uroepithelial cells (UECs) and tracheal epithelial cells (TECs). Irrespective of the type of epithelial cells, adhesion of the MS+MR+ (type 1.3) fimbriated Klebsiella strain was significantly stronger than adhesion of strains carrying only type 1 (MS+MR-) or type 3 (MS-MR+) fimbriae. The coexpression of P-like fimbriae increased the adhesive properties of Klebsiella strains to UECs but not to TECs. Adhesion of P-like fimbriated Klebsiella strains to UECs was significantly inhibited in the presence of the P+ fimbriae-specific Gal alpha-4-Gal beta (galabiose). Such adhesion was unrelated to the coexpression of type 1, type 3 or type 1.3 fimbriae. However, adhesion to TECs was only moderately inhibited.

Cross-reactivity between Borrelia burgdorferi and "arthrogenic" bacteria in sera from patients with reactive arthritis.

The occurrence of specific antibodies for "arthrogenic bacteria" and Borrelia burgdorferi was analysed in sera samples from 30 patients with reactive arthritis. The control group consisted of 30 healthy blood donors. Our data showed that 66.6% (20) of the 30 examined patients had positive tests for Borrelia burgdorferi antigens and of all the patients, most of them (85%) had increased antibody levels against Salmonella antigens, 30% had increased levels of antibodies against Shigella antigens and 10% had antibodies for Yersinia antigens. Our findings indicated that the presence of antibodies to Borrelia burgdorferi and "arthrogenic enteric bacteria" in sera samples of patients with REA is evidence of wide cross-reactivity between these microorganisms.

[Cytotoxin vacuolization of Helicobacter pylori]. / Cytotoksyna wakuolizujaca Helicobacter pylori.

Helicobacter pylori is now recognized as the major causative agent of chronic superficial gastritis in humans. The virulence factors of H. pylori are still poorly understood. Vacuolating cytotoxin (VacA) is one of the factors that has been identified so far. VacA induces cytoplasmic vacuolation in eukaryotic cells. The vacA gene encodes a precursor protein of 140 kDa which consists of a 33-amino acid signal sequence, the 87 kDa cytotoxin and a 50 kDa C-terminal domain. The 50 kDa domain is involved in translocation of VacA across outer membrane. Sequence analysis of vacA gene derived from different strains of H. pylori revealed the existence of several families of vacA gene allels. Analysis of a clinically isolated strains of H. pylori showed the correlation between presence of specific vacA allels, VacA activity and peptic ulceration.

[Strains of the genus Acinetobacter and their role in nosocomial infections]. / Drobnoustroje rodzaju Acinetobacter i ich rola w zakazeniach szpitalnych.

The paper presents the taxonomy, biochemical and physiological properties, and virulence factors of Acinetobacter strains. Hospital epidemiology and mechanisms of resistance to antibiotics in Acinetobacter is also described.

Helicobacter pylori antibodies in sera of children suffering from chronic abdominal pain.

107 pediatric patients aged 9 to 18 with persistent gastric complaints were examined serologically and bacteriologically for Helicobacter pylori. Helicobacter was identified in 48 (45%) of individuals. 51 (48%) of children were found to be seropositive when H. pylori antibodies were detected by the ELISA; 56 (52%) when the passive haemagglutination test was used, and 41 (38%) in the latex agglutination test. 25% of culture-negative patients were found to be seropositive. The percentage of raised H. pylori antibody titres in the control (healthy subjects) varied from 20 to 27%, depending on the method applied.

[Epidemiologic investigation of infection with Klebsiella using phage typing as a method]. / Epidemiologiczne badania zakazen paleczkami Klebsiella z uzyciem lizotypii jako metody.

In epidemiological investigations of infections with Klebsiella carried on by us for many years, a lysotyping method was used with a success. The results which are now being presented deal with 638 strains of Klebsiella pneumoniae and Klebsiella oxytoca originating from patients treated in hospitals in Wroclaw, Kraków, Gdansk and Sosnowiec during the years 1986-1992. Susceptibility of strains to the standard set of 14 phages used since ten years decreased significantly, when compared with previously typed strains of Klebsiella. Out of 312 susceptible strains of Klebsiella, majority (302) represented 47 phage types described previously. Sporadic appearance of new phage types was observed. Some phagotypes (37, 47, 112, 117, 119, 142, 153 and 157) were represented most frequently and concerned 55% of susceptible strains. High repeatability of phage types in consecutive groups of typed strains suggests a need for continuation of this method for typing Klebsiella. Decreased susceptibility of strains to standard set of phages requires introduction of new typing bacteriophages.

[Hemolytic properties of bacteria from the genus Acinetobacter]. / Hemolityczne wlasciwosci paleczek z rodzaju Acinetobacter.

Hemolytic activity of 370 strains of Acinetobacter was investigated. They represented species A. baumanii (195), A. junii (70), A. lwofii (71) and A. haemolyticus (27) and were isolated from hospitalized patients. Direct and intermediate hemolysins were tested in the plate test with application of human, sheep, bovine and rabbit blood, incubating cultures at 22 and 37 degrees C for 3 days. Hemolysins of A. lwoffii were more active at 22 degrees C against rabbit and sheep erythrocytes. Direct hemolysins produced by remaining species of Acinetobacter hemolyzed most easily human erythrocytes. Out of 27 strains of A. haemolyticus, 26 produced hemolysins. Intermediate hemolysins, produced only by A. junii (43% of strains) and A. haemolyticus (37%), were active only against animal erythrocytes. A. baumanii and A. lwofii produced only intermediate hemolysins and percentage of strains producing them was, respectively, 3.6 and 7.0.

[Occurrence of species of the Acinetobacter genus in material from patients and in the hospital environment]. / Wystepowanie gatunków rodzaju Acinetobacter w materiale od chorych i w srodowisku szpitalnym.

370 clinical strains of genus Acinetobacter were classified in accordance of taxonomy of this group of bacteria introduced by Nouvet and Grimont (1986). Most frequent species isolated was A. baumanii (195), followed by A. lwoffii (71), A. junii (79) and A. haemolyticus (27). A. calcoaceticus and A. jonsonii were present only sporadically. A. baumanii was isolated from bronchial secretions (36.9%), sputum (20.5%), blood (8.7%), pus (8.2%) and ur@ine (8.2%). A. lwoffi was isolated above all from throat smears (26.8%), sputum (16.9%), bronchial secretions (16.9%) and urine (16.9%). A. junii was present in sputum (25.7%), blood (17.6%), throat smears (17.6%), bronchial secretions (13.5%) and urine (12.2%).