Seasonality of Clostridium difficile infections in Southern Germany.

Between 2000 and 2009, the total number of patients with Clostridium difficile infections increased considerably in Southeastern Germany. A clear seasonality was observed with a higher number of affected patients occurring in the winter months (January-March). Moxifloxacin and erythromycin-resistant C. difficile PCR ribotypes 001 (72%) and 027 (4·6%) were the most commonly isolated strains.

Culture and successful eradication of Helicobacter pylori from heterotopic gastric mucosa.

Helicobacter pylori colonizes the gastric mucosa of humans and can cause chronic gastritis, peptic ulcer disease, gastric cancer or mucosa-associated-lymphoid tissue (MALT) lymphoma. Here, we report the case of a 61-year-old male patient who presented with tickle of the throat, globus sensation and heartburn. In an esophagogastroduodenoscopy subpharyngeal localized heterotopic gastric mucosa (HGM), reflux esophagitis and a chronic gastritis were diagnosed. HGM and stomach were H. pylori positive as proven by culture and histopathological examination. After eradication therapy with a proton pump inhibitor (PPI), amoxicillin and clarithromycin followed by PPI treatment, the patient reported clinical improvement and the histopathological changes in the HGM due to H. pylori infection improved, too. This case report demonstrates that culture and susceptibility testing of H. pylori using established protocols succeeds not only from tissue samples of the stomach but also from heterotopic gastric mucosa. Eradication therapy may not only improve typical H. pylori associated discomforts of the stomach but also extragastric signs and symptoms of H. pylori infection.

[Networks of National Reference Centers and associated Consiliary Laboratories in Germany]. / Referenznetzwerke aus Nationalen Referenzzentren mit assoziierten Konsiliarlaboratorien in Deutschland.

Since 1995, the Robert Koch-Institute in agreement with the Federal Ministry of Health in Germany has increased the funding of National Reference Centers (NRC) and Consiliary Laboratories (CL) for laboratory-based surveillance of selected infection pathogens and infectious disease syndromes. Their goal is to improve efficient protection from infections and to supplement infectious disease surveillance by monitoring selected pathogens. Currently there are 19 NRC and 48 CL, nominated for a duration of 3 years. In order to enhance the effectiveness and cooperation of the system, ten National Networks were launched in 2009. The aim of these networks is to facilitate exchange on diagnostic methods and prevention concepts and to improve the geographic coverage of the services. Furthermore, the networks provide an opportunity to work on issues beyond single pathogens more productively and efficiently. In addition, the inclusion of external and international specialists should to be included more often in the future. The activities of the networks are evaluated by the commission for infectious disease epidemiology. The commission develops promotion modalities to support collaboration between NRC and CL and to adapt it to more closely meet the requirements at the national and international levels.

Recognition of Clostridium difficile PCR-ribotypes 001, 027 and 126/078 using an extended MALDI-TOF MS system.

During the last decade, Clostridium difficile infection (CDI) increased markedly inside as well as outside of hospitals. In association with the occurrence of new hypervirulent C. difficile strains, CDI became more important. Until now typing of C. difficile strains has been enabled by PCR-ribotyping. However, this method is restricted to specialized laboratories combined with high maintenance cost. Therefore, we tested MALDI-TOF mass spectrometry for typing of C. difficile to provide a fast method for surveillance of CDI. Using a standard set of 25 different C. difficile PCR ribotypes a database was made by different mass spectra recorded in the SARAMIS software (AnagnosTec, Zossen, Germany). The database was validated with 355 C. difficile strains belonging to 29 different PCR ribotypes collected prospectively from all submitted feces samples in 2009. The most frequent PCR ribotypes were type 001 (70%), 027 (4.8%) and 078/126 (4.7%). All three types were recognized by MALDI-TOF MS. We conclude that an extended MALDI-TOF system was capable to recognize specific markers for ribotypes 001, 027 and 078/126 allowing an effective identification of these strains.

Correlations between bed occupancy rates and Clostridium difficile infections: a time-series analysis.

A time-series analysis was performed to identify the impact of bed occupancy rates and length of hospital stay on the incidence of Clostridium difficile infections (CDI). Between January 2003 and July 2008, a mean incidence of 0·5 CDI cases/1000 patient days was recorded. Application of a multivariate model (R2=0·50) showed that bed occupancy rates on general wards (P<0·01) and length of stay in intensive care units (ICUs) (P<0·01) influenced the incidence of CDI. Overcrowding on general wards and long periods in ICUs were identified as being positively associated with the incidence of CDI.

Association of ciprofloxacin prescriptions to outpatients to Clostridium difficile infections.

To study if antibiotic treatment of outpatients had triggered Clostridium difficile infections (CDI), prescription numbers were compared with CDI-affected patient numbers. A strong correlation was observed for ciprofloxacin (R=0.917), suggesting that increased use of ciprofloxacin by outpatients contributed to increased numbers of CDI. These findings deserve further investigation as they may have an impact on future decisions regarding antibiotic prescribing.

[Emergence of clostridium difficile ribotype 027 in Germany: epidemiological and clinical characteristics]. / Clostridium-difficile-Ribotyp 027: Epidemiologie und Klinik des erstmaligen endemischen Auftretens in Deutschland.

INTRODUCTION: In September 2007 an increase of severe Clostridium difficile-associated infections (CDI) was noticed in a hospital in the city of Trier, Germany. It was assumed that a new, possibly hypervirulent strain (PCR ribotype 027) was related to these events. An outbreak investigation was initiated by the local health authorities and the Robert Koch Institute to describe the epidemiology of the possible outbreak and to identify and control the possible sources. METHODS: In addition to retrospective case-finding of severe CDI and ribotype 027 infections by analysis of patient documents and certificates of death, an active surveillance system for severe CDI and ribotype 027 infections was established in the 6 hospitals of the affected region. In all suspected cases, a test for toxin A/B and a stool culture for C. difficile were conducted simultaneously. Bacterial isolates were further characterised by PCR ribotyping. Data on the course of disease, case fatality, and possible risk factors for CDI-related deaths were assessed using a standardised questionnaire. Environmental investigations were done. RESULTS: By 31 January 2008, 27 cases of severe CDI and 21 cases with C. difficile ribotype 027 infections were found in the area under investigation. Active surveillance found 76 of 399 (19 %) patients positive for C. difficile. In 20 patients, PCR ribotyp 027 could be proven. In total, 9 deaths occurred (19 %). An existing immunosupressive therapy (OR 35.8; 95 % CI 2.8 - 464.5) was related to case fatality in the multivariate analysis. Severe cases of CDI were also observed in non-ribotype 027 infections. In the screening of hospital personnel (n = 161), 6 % were found positive for toxin A/B. DISCUSSION: This investigation demonstrated the endemicity of C. difficile PCR ribotype 027 in Germany for the first time. As a consequence from this study, severe CDI became a reportable disease in Germany at the end of 2007. In addition to hygienic measures, the critical use of antibiotics is an important measure to prevent a further increase of CDI.

S3-guideline "helicobacter pylori and gastroduodenal ulcer disease" of the German society for digestive and metabolic diseases (DGVS) in cooperation with the German society for hygiene and microbiology, society for pediatric gastroenterology and nutrition e. V., German society for rheumatology, AWMF-registration-no. 021 / 001.

This guideline updates a prior consensus recommendation of the German Society for Digestive and Metabolic Diseases (DGVS) from 1996. It was developed by an interdisciplinary cooperation with representatives of the German Society for Hygiene and Microbiology, the Society for Pediatric Gastroenterology and Nutrition (GPGE), and the German Society for Rheumatology. The guideline is methodologically based on recommendations of the Association of the Scientific Medical Societies in Germany (AWMF) for providing a systematic evidence-based S 3 level consensus guideline and has also implemented grading criteria according to the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) process. Clinical applicability of study results as well as specifics for Germany in terms of epidemiology, antibiotic resistance status, diagnostics, and therapy were taken into account.

[Establishment of Networks of National Reference Centres and associated Consiliary Laboratories in Germany]. / Etablierung von Referenznetzwerken aus Nationalen Referenzzentren mit assoziierten Konsiliarlaboratorien in Deutschland.

The German Federal Ministry of Health has funded National Reference Centres (NRC) for laboratory-based surveillance of selected infection pathogens and infections disease syndromes. This selection is based on the epidemiologic relevance of the pathogens, specific diagnostic requirements, antimicrobial resistance and need for public health measures. Currently there are 18 NRC, nominated for a duration of 3 years. Toward the end of a nomination period, each NRC is evaluated by an expert committee, based on the catalogue of core tasks. In order to expand the spectrum of competencies 47 consiliary laboratories on additional pathogens of special epidemiologic importance have been named. Their main function is to provide information and consultation on special diagnostic issues. In order to further improve the effectiveness and cooperation of the system Networks have been created. The aim of the Networks is to facilitate exchange of diagnostic methods and prevention concepts and to improve the geographic coverage of the services.

Increased number of Clostridium difficile infections and prevalence of Clostridium difficile PCR ribotype 001 in southern Germany.

In recent years, Clostridium difficile infection (CDI) has emerged as an increasing problem, both in in- and outpatients. In a rural region of southern Germany, the annual number of C. difficile toxin (Tcd)-positive patients has increased from 95 to 796 in the period from 2000 to 2007. Simultaneously, the proportion of positive tests among all Tcd examinations has risen from 7.0% to 12.8%, indicating that the higher number of affected patients was not solely due to an increase in the number of assays. Elevated numbers of CDI have recently been associated with outbreaks of the ribotype 027 strain, particularly in North America. This strain has also been isolated in Europe, including in Germany. Ribotyping and PCR testing for binary toxin genes of C. difficile strains isolated from in- and outpatients demonstrate a predominance (59%) of C. difficile ribotype 001, which exhibits antibiotic resistance to erythromycin, ciprofloxacin, and moxifloxacin, but lacks binary toxin genes. In summary, in our region of Germany, the number of patients affected by CDI has increased, probably due to spread of C. difficile ribotype 001.

Cationic Yersinia antigen-induced chronic allergic arthritis in rats. A model for reactive arthritis in humans.

Cationic antigens are known to have considerable arthritogenic potential in experimental systems. During a systematic search for suitable, naturally occurring candidates an intracellular protein was isolated from the ribosomal pellet of Yersinia enterocolitica 0:3, a bacterial strain associated with reactive arthritis in humans. The protein is highly cationic, contains two 19-kD polypeptide chains linked by a disulfide bond, and reveals a strong tendency for spontaneous aggregation. It is suggested to be a nucleic acid binding protein. We tested this antigen for its ability to induce arthritis after intra-articular challenge in preimmunized rats. An acute inflammatory phase followed by transition to chronicity was observed both by technetium-99m scintigraphy and from histology. Massive polymorphonuclear leucocyte infiltration of the synovium was seen early on and fibrosis and thickening of the joint capsule occurred in later stages. Control groups showed no evidence of inflammation. Western blot and ELISA analysis of unselected sera from Yersinia enterocolitica 0:3-infected patients revealed antibodies to the antigen in the majority of cases, whereas healthy individuals rarely reacted. This is the first report of a naturally occurring cationic antigen capable of inducing immunologic tissue injury; it justifies the speculation that cationic antigens from prokaryotic cells could trigger reactive arthritis in humans.

Helicobacter pylori eradication and gastric ulcer healing--comparison of three pantoprazole-based triple therapies.

AIM: To study the efficacy of three pantoprazole-based triple therapy regimens for the eradication of Helicobacter pylori infection and gastric ulcer healing. METHODS: In an open, multi-centre, randomized study, 519 H. pylori-positive patients with active gastric ulcer were randomized to receive pantoprazole (40 mg) (P) and two of three antibiotics: clarithromycin (500 mg) (C), metronidazole (500 mg) (M) or amoxicillin (1000 mg) (A). Triple therapy (PAC, PCM, PAM) was administered twice daily for 7 days, followed by pantoprazole until the ulcer had healed. Antrum and corpus biopsies were taken to determine the pattern of gastritis, to assess the H. pylori status and to determine the strain susceptibility to antibiotics, and from the ulcer margins and base to exclude malignancy. Scores based on the Sydney system were used to categorize the gastritis phenotypically. RESULTS: The H. pylori eradication rates for the per protocol (intention-to-treat) analysis were 89% (67%) for PAC, 83% (68%) for PCM and 76% (60%) for PAM, with a significant difference between PAC and PAM. Healing rates after 4 weeks were 91% for PAM, 90% for PCM and 88% for PAC (per protocol analysis). The eradication rates were lower in patients in whom strains resistant to any antibiotic used in the triple therapies were detected. Successful eradication [odds ratio, 5.2 (3.3; 8.3)] and the ulcer size (< 15 mm) were significant predictors for healing after 4 weeks. The regimens showed a comparable safety profile and compliance. CONCLUSIONS: Pantoprazole-based triple therapies are effective in the eradication of H. pylori infection in gastric ulcer patients, as reported in previous similar sized studies in duodenal ulcer patients. Successful eradication and an ulcer size of < 15 mm are the best predictors of gastric ulcer healing after 4 weeks.

Structural and functional analysis of the riboflavin synthesis genes encoding GTP cyclohydrolase II (ribA), DHBP synthase (ribBA), riboflavin synthase (ribC), and riboflavin deaminase/reductase (ribD) from Helicobacter pylori strain P1.

The functions of the riboflavin synthesis gene homologues ribA, ribBA, ribC, and ribD from Helicobacter pylori strain P1 were confirmed by complementation of defined Escherichia coli mutant strains. The H. pylori ribBA gene, which is similar to bifunctional ribBA genes of Gram-positive bacteria, fully complemented the ribB mutation and partially restored growth in a ribC mutant. However, ribBA did not complement the ribA mutation in E. coli, thus explaining the presence of the additional separate copy of the ribA gene in the H. pylori chromosome. In E. coli exclusively ribA conferred hemolytic activity and gave rise to production of molecules with fluorescence characteristics similar to flavins, as observed earlier. The E. coli hemolysin ClyA was not involved in causing the hemolytic phenotype. No riboflavin synthesis genes on plasmids conferred iron uptake functions to a siderophore-deficient mutant of E. coli. Marker exchange mutagenesis of the genes in H. pylori was not successful indicating that riboflavin synthesis is essential for basic metabolic functions of the gastric pathogen.

Identification and molecular analysis of superoxide dismutase isoforms in Helicobacter pylori.

Three electromorphs of iron superoxide dismutase (FeSOD) were identified among 29 Helicobacter pylori isolates by native gel electrophoresis and activity staining. The electromorphs designated isoforms A, B, and C are characterized by slow, intermediate and fast electrophoretic migration, respectively, which was not observed under denaturing conditions. The isoforms were not associated with virulence determinants and with the outcome of disease. Sequence analysis of the sodB gene in strains producing different FeSOD isoforms and comparison of deduced protein sequences revealed that differences in the electric migration behavior are associated with exchange of charged amino acids, suggesting that faster migration is caused by a more negative total charge of the proteins. Electrophoretic migration of native FeSOD was not influenced by changes in the iron cofactor concentration, oxidative stress, and different media, indicating that FeSOD isoforms represent stable strain-specific markers.

Routine identification of Campylobacter jejuni and Campylobacter coli from human stool samples.

Correct identification of Campylobacter jejuni and Campylobacter coli isolates to the species or subspecies level is a cumbersome but nevertheless important task for a routine diagnostic laboratory. The widely used biochemical tests might be often misleading while more sophisticated phenotypic or genotypic methods are not generally available. This investigation was performed to assess the performance of common biochemical identification in comparison with species-specific PCR and gas liquid chromatography of whole cell fatty acid extracts (GLC). A total of 150 consecutive isolates from human stool samples were investigated (134 C. jejuni ssp. jejuni, 14 C. coli, two Helicobacter pullorum). From these 144, 145 and 149 isolates were correctly identified by biochemistry, GLC and PCR, respectively. Biochemical identification of all C. jejuni isolates was confirmed by PCR. GLC detected both H. pullorum strains but misidentified two C. coli strains as C. jejuni and one C. jejuni strain as C. coli. No single method can be defined as 'gold standard' for identification of C. jejuni and C. coli but a combination of techniques is needed. Therefore a stepwise identification scheme starting with biochemical reactions is suggested. All results other than C. jejuni should be confirmed by further methods. For indoxyl acetate-positive isolates species-specific PCR is recommended while GLC seems to be advantageous in indoxyl acetate-negative isolates.

Cloning and characterization of the fur gene from Helicobacter pylori.

The fur homologue of Helicobacter pylori was isolated by screening a plasmid-based, genomic DNA library using the Fur titration assay (FURTA). The analysis of the DNA sequence revealed significant homology with Fur proteins from various other bacterial species. The highest degree of homology was observed for the Fur protein from Campylobacter jejuni. The H. pylori fur gene on a plasmid could partially complement the fur mutation in Escherichia coli strain H1681. The repressor activity depended on addition of iron to the medium indicating that iron acts as a co-repressor for the H. pylori protein similar to Fur from other bacteria. Comparison of Fur from H. pylori strain NCTC11638 with the recently published genomic DNA sequence of another strain (26695) confirmed the identity of the fur homologue and revealed that the fur locus is highly conserved in both strains.

Discrimination of Helicobacter pullorum and Campylobacter lari by analysis of whole cell fatty acid extracts.

Helicobacter pullorum and Campylobacter lari are rarely isolated from humans with acute enteritis. Hitherto the two species could only be identified by genotypic techniques. Gas liquid chromatography of whole cell fatty acid extracts is described as the first phenotypic method for discrimination of the two species. Cholesteryl glucoside, a characteristic feature of the genus Helicobacter, but seldom found in other bacteria, could not be detected in Helicobacter pullorum. Therefore, rapid determination of this glycolipid may serve as a discrimination marker for Helicobacter pullorum from most other Helicobacter species.

Identification of iron-regulated genes of Helicobacter pylori by a modified fur titration assay (FURTA-Hp).

The Escherichia coli-based Fur titration assay (FURTA), although a powerful tool for identification of genes regulated by the ferric uptake regulator (Fur), was unsuccessful for the gastric pathogen Helicobacter pylori. The FURTA was modified by construction of an E. coli indicator strain producing H. pylori Fur only. The promoter regions of the ferric citrate receptor homolog fecA2 and the riboflavin synthesis gene ribBA were both positive in the modified FURTA, but negative in the original FURTA. Transcription of fecA2 and ribBA was demonstrated to be iron-repressed in H. pylori. This type of modification should allow FURTA analysis for bacteria with Fur binding sequences poorly recognized by E. coli Fur.

The role of Helicobacter pylori virulence factors in interleukin production by monocytic cells.

Helicobacter pylori infection results in chronic gastritis, which is initiated by the release of cytokines like interleukin (IL)-12 and IL-8 from mononuclear cells, and IL-8 from gastric epithelial cells. The severity of gastritis is influenced both by host factors and by bacterial factors such as the Cag proteins and the vacuolating cytotoxin VacA. Amounts of IL-12 and IL-8 produced by monocytic THP-1 cells differed considerably between the eight H. pylori isolates tested, but in contrast to H. pylori-induced IL-8 production by gastric epithelial cells, did not correlate to the Cag and VacA types of the strains. Apparently, in addition to Cag and VacA, other bacterial factors determine the extent in which H. pylori induced IL production in monocytes.