Infectious diseases are among the leading causes of morbidity and mortality worldwide. The spectrum of clinical manifestations of infections is highly variable, ranging from asymptomatic infection or mild illness to rapid progression of disease and death. Twin studies first showed an inheritable component of many infections and epidemiological and genetic studies revealed definite gene loci and polymorphisms for most of the clinically relevant infectious diseases. Reliable genetic markers which represent susceptibility or resistance to infections, prognosis of disease and response to treatment are necessary to define risk populations and to plan therapy regimens. Genetic research can also help in identifying target structures for novel therapy strategies and anitimicrobial agents. In this article the genetic background of important infections is reviewed and examples of successful exploitation of genetic findings and translation into practical medicine are given.
Clinical and Experimental DermatologyVolume 34, Issue 7 p. e292-e292 Yersinia enterocolitica: another factor in the pathogenesis of chronic urticaria? S. Hellmig, S. Hellmig Departments of General Internal MedicineSearch for more papers by this authorK. Troch, K. Troch Departments of General Internal MedicineSearch for more papers by this authorS. J. Ott, S. J. Ott Departments of General Internal MedicineSearch for more papers by this authorU. R. Fölsch, U. R. Fölsch Departments of General Internal MedicineSearch for more papers by this authorT. Schwarz, T. Schwarz Dermatology, University Hospital of Schleswig-Holstein, Campus Kiel, Schittenhelmstr. 12, 24116 Kiel, GermanySearch for more papers by this author S. Hellmig, S. Hellmig Departments of General Internal MedicineSearch for more papers by this authorK. Troch, K. Troch Departments of General Internal MedicineSearch for more papers by this authorS. J. Ott, S. J. Ott Departments of General Internal MedicineSearch for more papers by this authorU. R. Fölsch, U. R. Fölsch Departments of General Internal MedicineSearch for more papers by this authorT. Schwarz, T. Schwarz Dermatology, University Hospital of Schleswig-Holstein, Campus Kiel, Schittenhelmstr. 12, 24116 Kiel, GermanySearch for more papers by this author First published: 02 September 2009 https://doi.org/10.1111/j.1365-2230.2009.03226.xCitations: 1 Conflict of interest: none declared. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume34, Issue7October 2009Pages e292-e292 RelatedInformation
Introduction: Chronic urticaria is thought to have numerous causative factors including a large variety of infectious conditions, food intake, and drugs. The impact of Helicobacter pylori infection has been studied with ambiguous results. The aim of this study was to investigate the course of chronic urticaria in H. pylori-positive patients undergoing eradication compared to H. pylori-negative urticaria patients.Patients and Methods: We included 74 urticaria patients with positive H. pylori breath test and 74 age- and sex-matched H. pylori-negative controls. All urticaria patients underwent an extensive diagnostic work-up to search for trigger foci. H. pylori-infected patients were submitted to eradication therapy. Mean follow-up time was 58 months.Results: Neither the prevalence of H. pylori nor the eradication therapy had an influence on the clinical course of chronic urticaria. In 81.1% of H. pylori-infected patients at least one additional infectious focus was found. Nevertheless, it could be shown that individuals that described any kind of symptom relief presented with higher serum IgE levels at diagnosis (198.1 vs 115.7 kU/L, p = .027) but this effect was independent of H. pylori infection.Conclusions: In conclusion there is no evidence that eradication of H. pylori improves the outcome in patients with chronic urticaria. The high rate of spontaneous remission and the coexisistance of multiple foci will always obscure the evaluation of any specific antimicrobial therapy.
Background: The intestinal microbiota plays a critical role in the pathophysiology of pouchitis, a major complication after ileal pouch anal anastomosis in patients with ulcerative colitis. Recently, controlled trials have demonstrated that probiotics are effective in maintenance of remission in pouchitis patients. However, the mechanism by which therapy with probiotics works remains elusive. This study explores the role of the bacterial and fungal flora in a controlled trial for maintenance of remission in pouchitis patients with the probiotic VSL#3 compound.Methods: The mucosa associated pouch microbiota was investigated before and after therapy with VSL#3 by analysis of endoscopic biopsies using ribosomal DNA/RNA based community fingerprint analysis, clone libraries, real time polymerase chain reaction (PCR), and fluorescence in situ hybridisation. Patients were recruited from a placebo controlled remission maintenance trial with VSL#3.Results: Patients who developed pouchitis while treated with placebo had low bacterial and high fungal diversity. Bacterial diversity was increased and fungal diversity was reduced in patients in remission maintained with VSL#3 (p = 0.001). Real time PCR experiments demonstrated that VSL#3 increased the total number of bacterial cells (p = 0.002) and modified the spectrum of bacteria towards anaerobic species. Taxa specific clone libraries for Lactobacilli and Bifidobacteria showed that the richness and spectrum of these bacteria were altered under probiotic therapy.Conclusions: Probiotic therapy with VSL#3 increases the total number of intestinal bacterial cells as well as the richness and diversity of the bacterial microbiota, especially the anaerobic flora. The diversity of the fungal flora is repressed. Restoration of the integrity of a "protective'' intestinal mucosa related microbiota could therefore be a potential mechanism of probiotic bacteria in inflammatory barrier diseases of the lower gastrointestinal tract.
Infection and innate immunity have been suggested as playing an important role in the pathogenesis of atherosclerosis. The recently discovered pattern-recognition receptor (PRR) proteins initiate signalling after host-pathogen interactions and several PRRs, especially the Toll-like receptor 4 (TLR4), have been shown to be involved in the development and progression of atherosclerosis. A new addition to the PRRs is CARD4, a gene that encodes the protein nucleotide-binding oligomerization domain 1 (NOD1) and that seems to be associated with barrier function in chronic inflammatory disorders. Recently, a functional variant in the CARD4 gene, the insertion-deletion polymorphism ND1+32656, has been associated with inflammatory barrier diseases (inflammatory bowel diseases and asthma). We analysed the frequencies of this known functional mutation in the CARD4 gene and of the two adjacent variants, rs2075822 and rs2907748, in a German sample of 1440 unrelated early onset coronary heart disease (CHD) patients and healthy controls. Genotype and haplotype data showed no evidence for a significant association of these CARD4 variants with CHD. Our results suggest that the analysed CARD4 mutations do not play a major role in the aetiology of CHD.
Background— Bacterial infection has been discussed as a potential etiologic factor in the pathophysiology of coronary heart disease (CHD). This study analyzes molecular phylogenies to systematically explore the presence, frequency, and diversity of bacteria in atherosclerotic lesions in patients with CHD. Methods and Results— We investigated 16S rDNA signatures in atherosclerotic tissue obtained through catheter-based atherectomy of 38 patients with CHD, control material from postmortem patients (n=15), and heart-beating organ donors (n=11) using clone libraries, denaturating gradient gel analysis, and fluorescence in situ hybridization. Bacterial DNA was found in all CHD patients by conserved PCR but not in control material or in any of the normal/unaffected coronary arteries. Presence of bacteria in atherosclerotic lesions was confirmed by fluorescence in situ hybridization. A high overall bacterial diversity of >50 different species, among them Staphylococcus species, Proteus vulgaris , Klebsiella pneumoniae , and Streptococcus species, was demonstrated in >1500 clones from a combined library and confirmed by denaturating gradient gel analysis. Mean bacterial diversity in atheromas was high, with a score of 12.33±3.81 (range, 5 to 22). A specific PCR detected Chlamydia species in 51.5% of CHD patients. Conclusions— Detection of a broad variety of molecular signatures in all CHD specimens suggests that diverse bacterial colonization may be more important than a single pathogen. Our observation does not allow us to conclude that bacteria are the causative agent in the etiopathogenesis of CHD. However, bacterial agents could have secondarily colonized atheromatous lesions and could act as an additional factor accelerating disease progression.
BACKGROUND AND AIMS:The intestinal bacterial microflora plays an important role in the aetiology of inflammatory bowel disease (IBD). As most of the colonic bacteria cannot be identified by culture techniques, genomic technology can be used for analysis of the composition of the microflora.PATIENTS AND METHODS:The mucosa associated colonic microflora of 57 patients with active inflammatory bowel disease and 46 controls was investigated using 16S rDNA based single strand conformation polymorphism (SSCP) fingerprint, cloning experiments, and real time polymerase chain reaction (PCR).RESULTS:Full length sequencing of 1019 clones from 16S rDNA libraries (n = 3) revealed an overall bacterial diversity of 83 non-redundant sequences-among them, only 49 known bacterial species. Molecular epidemiology of the composition of the colonic microflora was investigated by SSCP. Diversity of the microflora in Crohn's disease was reduced to 50% compared with controls (21.7 v 50.4; p<0.0001) and to 30% in ulcerative colitis (17.2 v 50.4; p<0.0001). The reduction in diversity in inflammatory bowel disease was due to loss of normal anaerobic bacteria such as Bacteroides species, Eubacterium species, and Lactobacillus species, as revealed by direct sequencing of variable bands and confirmed by real time PCR. Bacterial diversity in the Crohn's group showed no association with CARD15/NOD2 status.CONCLUSIONS:Mucosal inflammation in inflammatory bowel disease is associated with loss of normal anaerobic bacteria. This effect is independent of NOD2/CARD15 status of patients.
The composition of the human intestinal flora is important for the health status of the host. The global composition and the presence of specific pathogens are relevant to the effects of the flora. Therefore, accurate quantification of all major bacterial populations of the enteric flora is needed. A TaqMan real-time PCR-based method for the quantification of 20 dominant bacterial species and groups of the intestinal flora has been established on the basis of 16S ribosomal DNA taxonomy. A PCR with conserved primers was used for all reactions. In each real-time PCR, a universal probe for quantification of total bacteria and a specific probe for the species in question were included. PCR with conserved primers and the universal probe for total bacteria allowed relative and absolute quantification. Minor groove binder probes increased the sensitivity of the assays 10- to 100-fold. The method was evaluated by cross-reaction experiments and quantification of bacteria in complex clinical samples from healthy patients. A sensitivity of 10(1) to 10(3) bacterial cells per sample was achieved. No significant cross-reaction was observed. The real-time PCR assays presented may facilitate understanding of the intestinal bacterial flora through a normalized global estimation of the major contributing species.
The human gastrointestinal tract harbors an extremely diverse and complex microbial ecosystem. Most of the existent data about the enteric microflora have been generated using stool samples, but the collection and storage of fecal samples are often problematic. The influence of the storage of stool samples on the bacterial diversity and the degradation of bacterial DNA was analysed in this study. Stool samples from 5 healthy volunteers were exposed to different storage temperatures and durations. The bacterial diversity and the amount of intact bacterial DNA were analysed by single-stranded conformation polymorphism analysis (SSCP) and real-time polymerase chain reaction (PCR), both using a 16S rDNA approach. Additionally, biopsy specimens were taken from 3 of the 5 individuals to compare fecal and mucosal flora. The bacterial diversity of the fecal flora and the total number of bacteria were significantly reduced after 8 and 24 hours at both room temperature and 4 degrees C. The mucosa-associated bacterial microflora showed substantial differences compared with the fecal flora. The observed alterations of fecal flora during storage point to the difficulty of the molecular analysis of the bacterial diversity and the enumeration of bacterial cells in fecal samples.