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D Y Graham

Publications and source records attributed to D Y Graham.

At least 37 records · Page 2Linked to original sources
PubMed2004

Challenge model for Helicobacter pylori infection in human volunteers.

BACKGROUND: A reliable challenge model is needed to evaluate Helicobacter pylori vaccine candidates. METHODS: A cag pathogenicity island negative, OipA positive, multiple antibiotic susceptible strain of H pylori obtained from an individual with mild gastritis (Baylor strain 100) was used to challenge volunteers. Volunteers received 40 mg of famotidine at bedtime and 10(4)-10(10) cfu of H pylori in beef broth the next morning. Infection was confirmed by (13)C urea breath test ((13)C-UBT), culture, and histology. Eradication therapy was given four or 12 weeks post challenge and eradication was confirmed by at least two separate UBTs, as well as culture and histology. RESULTS: Twenty subjects (nine women and 11 men; aged 23-33 years) received a H pylori challenge. Eighteen (90%) became infected. Mild to moderate dyspeptic symptoms occurred, peaked between days 9 and 12, and resolved. Vomitus from one subject contained >10(3) viable/ml H pylori. By two weeks post challenge gastric histology showed typical chronic H pylori gastritis with intense acute and chronic inflammation. The density of H pylori (as assessed by cfu/biopsy) was similarly independent of the challenge dose. A minimal infectious dose was not found. Gastric mucosal interleukin 8 levels increased more than 20-fold by two weeks after the challenge. CONCLUSION: Challenge reliably resulted in H pylori infection. Infection was associated with typical H pylori gastritis with intense polymorphonuclear cell infiltration and interleukin 8 induction in gastric mucosa, despite absence of the cag pathogenicity island. Experimental H pylori infection is one of the viable approaches to evaluate vaccine candidates.

Adolescent↗
PubMed2003

Meta-analysis: proton pump inhibitor or H2-receptor antagonist for Helicobacter pylori eradication.

AIM: To compare H2-receptor antagonists and proton pump inhibitors as adjuvants to triple therapy for Helicobacter pylori eradication. METHODS: H. pylori-infected patients with peptic ulcer were randomized to receive either 300 mg nizatidine or 30 mg lansoprazole plus 1 g amoxicillin and 500 mg clarithromycin taken b.d. for 7 days. H. pylori eradication was assessed 4 weeks after therapy. Using meta-analytical techniques, we combined the results of this study with other randomized controlled comparisons of H2-receptor antagonists and proton pump inhibitors as adjuvants to triple therapy. RESULTS: One hundred and one patients were randomized. H. pylori eradication was 94% (47/50) [95% confidence interval (CI), 83-99%] (intention-to-treat) in the H2-receptor antagonist group vs. 86% (44/51) (95% CI, 74-94%) in the proton pump inhibitor group (P = 0.3). There has been a total of 12 similar studies (1415 patients). The overall efficacy was similar in intention-to-treat analysis: 78% (549/701) with H2-receptor antagonists vs. 81% (575/714) with proton pump inhibitors (odds ratio, 0.86; 95% CI, 0.66-1.12). A non-significant trend favouring H2-receptor antagonist (79% vs. 69%; odds ratio, 1.14; 95% CI, 0.76-1.71; P = 0.5) was seen in the comparison of clarithromycin-containing regimens. In contrast, in non-clarithromycin-containing trials, there was a slight, but significant, advantage with proton pump inhibitors (85% vs. 78%; odds ratio, 0.64; 95% CI, 0.45-0.92; P = 0.02). CONCLUSION: Overall, proton pump inhibitor and H2-receptor antagonist antisecretory agents appear to be similarly effective as adjuvants for H. pylori triple therapy. It is unlikely that the direct anti-H. pylori effect of proton pump inhibitors is responsible for their ability to enhance anti-H. pylori therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

Early events in proton pump inhibitor-associated exacerbation of corpus gastritis.

BACKGROUND: Antisecretory therapy may exacerbate Helicobacter pylori corpus gastritis. The rate and mechanism(s) remain unknown. AIM: To investigate the early events in proton pump inhibitor therapy on antral and corpus H. pylori gastritis. METHODS: Nine H. pylori-infected volunteers underwent gastric biopsy with jumbo forceps for culture and histology. Histology was scored in the range 0-5 using a visual analogue scale. The depth of inflammation in gastric pits was scored in the range 1-3 (superficial or less than one-third, one-third to two-thirds and greater than two-thirds of the gastric pit, respectively). Tissue interleukin-1 beta and interleukin-8 levels were measured by enzyme-linked immunoabsorbent assay. Omeprazole, 20 mg b.d., was given for 6.5 days and biopsies were repeated on day 7. RESULTS: Proton pump inhibitor therapy resulted in a fall in H. pylori density in the antrum and corpus. Inflammation and tissue levels of interleukin-8 and interleukin-1 beta decreased in the antrum and increased in the corpus mucosa. There was a significant increase in the depth of inflammation to include the proliferative zone in the corpus. CONCLUSIONS: Within 1 week of starting proton pump inhibitor therapy, there was a marked extension of corpus inflammation into the gastric pit and an increase in corpus mucosal interleukin-1 beta and interleukin-8 levels. H. pylori eradication should be considered for all patients receiving long-term antisecretory therapy.

Adult↗
PubMed2003

High-level beta-lactam resistance associated with acquired multidrug resistance in Helicobacter pylori.

Four clinical Helicobacter pylori isolates with high-level resistance to beta-lactams exhibited low- to moderate-level resistance to the structurally and functionally unrelated antibiotics ciprofloxacin, chloramphenicol, metronidazole, rifampin, and tetracycline. This pattern of multidrug resistance was transferable to susceptible H. pylori by natural transformation using naked genomic DNA from a clinical multidrug-resistant isolate. Acquisition of the multidrug resistance was also associated with a change in the genotype of the transformed multidrug-resistant H. pylori. DNA sequence analyses of the gene encoding penicillin binding protein 1A (PBP 1A) showed 36 nucleotide substitutions resulting in 10 amino acid changes in the C-terminal portion (the putative penicillin binding domain). Acquisition of beta-lactam resistance was consistently associated with transfer of a mosaic block containing the C-terminal portion of PBP 1A. No changes of genes gyrA, rpoB, rrn16S, rdxA, and frxA, and nine other genes (ftsI, hcpA, llm, lytB, mreB, mreC, pbp2, pbp4, and rodA1) encoding putative PBPs or involved in cell wall synthesis were found among the transformed resistant H. pylori. Antibiotic accumulations of chloramphenicol, penicillin, and tetracycline were all significantly decreased in the natural and transformed resistant H. pylori compared to what was seen with susceptible H. pylori. Natural transformation also resulted in the outer membrane protein profiles of the transformed resistant H. pylori becoming similar to that of the clinical resistant H. pylori isolates. Overall, these results demonstrate that high-level beta-lactam resistance associated with acquired multidrug resistance in clinical H. pylori is mediated by combination strategies including alterations of PBP 1A and decreased membrane permeability.

Amino Acid Sequence↗
PubMed2003

[Helicobacter pylori infection in a group of symptomatic and asymptomatic children and adolescents in the Czech Republic].

BACKGROUND: There exist only inconsistent results of studies on the relationship between Helicobacter pylori (H. pylori) infection and functional dyspepsia and/or recurrent abdominal pain in children and adolescents. The answer could bring a comparison of the epidemiological features of H. pylori infection between children and adolescents with dyspepsia and/or recurrent abdominal pain (symptomatic) and without these symptoms (asymptomatic), living in the Czech republic. METHODS AND RESULTS: Study includes children and adolescents (2-18 years) with upper gastrointestinal symptoms visiting paediatric gastroenterology department between 1994 and 1999. Age, sex, socioeconomic level matched control (asymptomatic) group consisted of children and adolescents visiting the general paediatric service with symptoms not related to the upper gastrointestinal tract. Demographic and socioeconomic factors, including parent(s) educational level, place of residence, living conditions, type of drinking water and pets in their household were evaluated. Serum of the children and adolescents was tested for H. pylori IgG by enzyme linked immunosorbent assay. In addition, the symptomatic children and adolescents underwent endoscopic examination and biopsies from gastric antrum and corpus were taken for the quick urease test, histology/histoscopy, and H. pylori cultivation. H. pylori infection in this group was stated when at least two tests were positive. Altogether 829 children and adolescents were examined, 624 cases were symptomatic and 205 represented controls (asymptomatic). The prevalence of infection was 33% among symptomatic children vs. 7.5% among controls (OR = 6.2, p.001) and was similar among boys and girls (32% vs. 34.5%, respectively). H. pylori prevalence increased with age among symptomatic children (10% for children below 6 years and 37% between 11 to 16 years) (p.001). In contrary, prevalence tended to fall with age among asymptomatic children (11% in children below 6 years vs. 6% in children over 10 years (OR = 2.0, 95% CI = 0.7-6.2). In both groups, an inverse correlation between H. pylori occurrence and mother's educational level was observed. The H. pylori incidence was 10% among asymptomatic children who drank water from municipal water supply or from a well vs. 3% among those who drank bottled water (OR = 4, 95% CI = 1.1 to 18, p.05). CONCLUSIONS: H. pylori infection was more prevalent among symptomatic children and adolescents vs. asymptomatic children and adolescents within the same population. H. pylori incidence increased with age among symptomatic children and adolescents and tended to fall among controls, showing deep differences between the two groups. With exception of the bottled water drinking, presence of any other factor studied represented significant risk for acquiring the H. pylori infection.

Adolescent↗
PubMed2002

Screening of gene expression profiles in gastric epithelial cells induced by Helicobacter pylori using microarray analysis.

BACKGROUND: H. pylori infection is a major risk factor in gastric cancer development. The availability of cDNA microarrays creates the unprecedented opportunity to examine simultaneously dynamic changes of multiple pathways affected by H. pylori infection. AIM: In this study we examined broad patterns of gene expression induced by H. pylori in the gastric cancer cell line 1739-CRL AGS cells in culture using the U95A microarray. METHODS: H. pylori were cocultured with AGS cells for 4, 12, 24 and 48 h. Total RNA was extracted and after labelling was used for detection of genes represented in the human U95A microarray set. Data analyses were performed using GeneChip and CLUSFAVOR software. RESULTS: Nearly 6000 genes present in the array were expressed by AGS cells. We report approximately 200 genes that showed the most marked changes. Our studies confirm the up-regulation of c-jun, jun-B, c-fos and cyclin D1 by H. pylori. We report for the first time the induction of the serine threonine kinase pim-1 and ATF3 by H. pylori infection of AGS cells. CONCLUSIONS: In this microarray analysis of gene expression induced by H. pylori in gastric epithelial cells, we identified a large number of unsuspected genes affected by H. pylori. Further, we show that unsupervised hierarchical cluster analysis can provide useful insight into the possible contribution of genes in specific pathways, based on their profile of expression.

Activating Transcription Factor 3↗
PubMed2002

Current concepts in the management of Helicobacter pylori infection--the Maastricht 2-2000 Consensus Report.

Significant progress and new insights have been gained in the 4 years since the first Maastricht Consensus Report, necessitating an update of the original guidelines. To achieve this, the European Helicobacter Pylori Study Group organized a meeting of specialists and experts from around the world, representatives from National Gastroenterology Societies and general practitioners from Europe to establish updated guidelines on the current management of Helicobacter pylori infection. The meeting took place on 21-22 September 2000. A "test and treat" approach is recommended in adult patients under the age of 45 years (the age cut-off may vary locally) presenting in primary care with persistent dyspepsia, having excluded those with predominantly gastro-oesophageal reflux disease symptoms, non-steroidal anti-inflammatory drug users and those with alarm symptoms. Diagnosis of infection should be by urea breath test or stool antigen test. As in the previous guidelines, the eradication of H. pylori is strongly recommended in all patients with peptic ulcer, including those with complications, in those with low-grade gastric mucosa-associated lymphoid tissue lymphoma, in those with atrophic gastritis and following gastric cancer resection. It is also strongly recommended in patients who are first-degree relatives of gastric cancer patients and according to patients' wishes after full consultation. It is advised that H. pylori eradication is considered to be an appropriate option in infected patients with functional dyspepsia, as it leads to long-term symptom improvement in a subset of patients. There was consensus that the eradication of H. pylori is not associated with the development of gastro-oesophageal reflux disease in most cases, and does not exacerbate existing gastro-oesophageal reflux disease. It was agreed that the eradication of H. pylori prior to the use of non-steroidal anti-inflammatory drugs reduces the incidence of peptic ulcer, but does not enhance the healing of gastric or duodenal ulcer in patients receiving antisecretory therapy who continue to take non-steroidal anti-inflammatory drugs. Treatment should be thought of as a package which considers first- and second-line eradication therapies together. First-line therapy should be with triple therapy using a proton pump inhibitor or ranitidine bismuth citrate, combined with clarithromycin and amoxicillin or metronidazole. Second-line therapy should use quadruple therapy with a proton pump inhibitor, bismuth, metronidazole and tetracycline. Where bismuth is not available, second-line therapy should be with proton pump inhibitor-based triple therapy. If second-line quadruple therapy fails in primary care, patients should be referred to a specialist. Subsequent failures should be handled on a case-by-case basis by the specialist. In patients with uncomplicated duodenal ulcer, eradication therapy does not need to be followed by further antisecretory treatment. Successful eradication should always be confirmed by urea breath test or an endoscopy-based test if endoscopy is clinically indicated. Stool antigen test is the alternative if urea breath test is not available.

Adult↗
PubMed2002

Low-salt bowel cleansing preparation (LoSo Prep) as preparation for colonoscopy: a pilot study.

BACKGROUND: Currently available colon cleansing preparations are often poorly tolerated. AIM: To evaluate the efficacy of a low-volume, low-salt preparation for colonoscopy. METHODS: This was a pilot study in patients scheduled for colonoscopy. The preparation consisted of 34 g of magnesium citrate and four bisacodyl tablets the day before the procedure, and one bisacodyl suppository on the morning of the procedure. RESULTS: Twenty patients (age range, 49-81 years; all males) were entered into the study. There were no significant side-effects associated with the preparation. All rated the taste as 'tolerable or better'. The examination was considered to be adequate, with no limitations, in 17 patients (85%), and was scored as good to excellent (no solid stool) in 11 (55%), acceptable (small amounts of solid stool) in six (30%) and poor in three (15%: two in-patients and one out-patient). Importantly, two of the failures then received a standard polyethylene glycol preparation and again failed to show adequate colon preparation. CONCLUSIONS: This pilot study showed that the low-salt colon cleansing preparation was an effective alternative preparation for colonoscopy.

Administration, Oral↗
PubMed2002

Colloidal bismuth subcitrate-based twice-a-day quadruple therapy as primary or salvage therapy for Helicobacter pylori infection.

OBJECTIVE: Helicobacter pylori (H. pylori) eradication rates in northern Sardinia using standard 1-wk triple therapies (i.e., a proton pump inhibitor and two antibiotics) are typically <60%, primarily because of antibiotic resistance. The aim of this study was to test b.i.d. quadruple therapy as primary and as salvage therapy in this population. METHODS: This was a prospective, single center study of consecutive dyspeptic H. pylori-infected patients. Therapy consisted of omeprazole 20 mg, tetracycline 500 mg, metronidazole 500 mg, and bismuth subcitrate caplets 240 mg, all b.i.d. with the midday and evening meals for 14 days. H. pylori status was evaluated by 13C-urea breath test and histology before and 4-6 wk after therapy. Eradication was defined as no positive test. RESULTS: We enrolled 118 consecutive dyspeptic patients (mean age 46 yr; 73 men, including 15 with peptic ulcer disease). Of the patients, 42 (38%) had failed prior therapy: twice in 21 cases, three times in 12, and four or more times in nine. The intention-to-treat cure rate was 95% (110 of 116) (95% CI = 90-98%) overall, and 98% per protocol, irrespective of diagnosis, age, prior treatment failure, or smoking status. Moderate or severe side effects were experienced by only 5% of patients. CONCLUSIONS: Bismuth subcitrate-based b.i.d. quadruple therapy was an excellent primary and salvage therapy and should be considered as first line therapy.

Adult↗
PubMed2001

Pattern of primary resistance of Helicobacter pylori to metronidazole or clarithromycin in the United States.

BACKGROUND: Therapy for Helicobacter pylori is generally empiric despite the fact that resistance to metronidazole and clarithromycin compromise therapeutic efficacy. The aim of this study was to aid clinicians in choosing a course of therapy for H pylori infection in the United States. METHODS: The frequency of primary clarithromycin and metronidazole resistance among H pylori isolated from patients enrolled in US-based clinical trials between 1993 and 1999 was reviewed in relation to patient age, sex, region of the United States, and test method (Etest and 2 agar dilution procedures). RESULTS: Clarithromycin and metronidazole resistance rates were based on the results of 3439 pretreatment Etest determinations and 3193 agar dilution determinations. Sex and age were available on 900 and 823 individuals, respectively. Metronidazole resistance was 39% by Etest and 21.6% by agar dilution (P<.001). Clarithromycin resistance was 12% by Etest and 10.6% by agar dilution. Amoxicillin or tetracycline resistance was rare. Metronidazole and clarithromycin resistance was more common in women than men (eg, 34.7% vs 22.6% for metronidazole and 14.1% vs 9.7% for clarithromycin (P =.01 and P =.06, respectively). Antibiotic resistance increased gradually up to age 70 years, then declined significantly (P<.05) regardless of test method. Regional differences in antimicrobial resistance did not occur. CONCLUSIONS: While age and sex had significant effects on resistance rates, regional differences were not present. The high prevalence of resistance to metronidazole and clarithromycin may soon require the performance of antimicrobial susceptibility testing of H pylori isolates prior to initiating treatment.

Adult↗
PubMed2001

Helicobacter pylori infection in preschool and school-aged minority children: effect of socioeconomic indicators and breast-feeding practices.

Helicobacter pylori infection was examined among 356 asymptomatic white Hispanic and black children aged 2--16 years attending 13 licensed day care centers in Houston. Demographic information and socioeconomic factors were evaluated. H. pylori status was determined by (13)C-urea breath testing. The prevalence of active H. pylori infection was 24% and increased with age. Prevalence was almost identical among white Hispanic and black children. Children living in the most crowded conditions were at the greatest risk for H. pylori acquisition, and an inverse correlation was seen between the mother's education and H. pylori positivity in children. Breast-feeding played a protective role against the acquisition of H. pylori infection. Understanding the epidemiology of H. pylori infection in childhood requires better understanding of the interactions between environment, ethnic group, and socioeconomic conditions.

Adolescent↗
PubMed2001

Alendronate and naproxen are synergistic for development of gastric ulcers.

BACKGROUND: Both alendronate sodium use and nonsteroidal anti-inflammatory drug use are associated with gastric ulcers. The aim of this study was to investigate whether alendronate and naproxen are synergistic as causes of gastric ulcers. METHODS: We performed an endoscopist-blind, randomized, crossover, single-center comparison of 10 mg/d of alendronate sodium, 500 mg of naproxen sodium twice daily, or the combination taken orally for 10 days in volunteers aged 30 years or older. Videoendoscopy was used to evaluate the presence and degree of mucosal damage to the esophagus, stomach, or duodenal bulb before and after each treatment. There was a 1- to 4-week washout between evaluations. RESULTS: Twenty-six healthy volunteers participated (18 women and 8 men), aged 30 to 50 years. Gastric ulcers were present in 2 subjects receiving alendronate (8%), in 3 receiving naproxen (12%), and in 10 receiving both (38%) (P<.05 for the combination vs either drug alone). CONCLUSIONS: Both alendronate and naproxen can cause gastric ulcers. The combination appears synergistic. Alendronate should be used with caution in those who simultaneously require nonsteroidal anti-inflammatory drugs.

Adult↗
PubMed2001

Helicobacter pylori and nonsteroidal anti-inflammatory drugs: interaction with proton pump inhibitor therapy for prevention of nonsteroidal anti-inflammatory drug ulcers and ulcer complications--future research needs.

Two recently reported studies of nonsteroidal anti-inflammatory drugs (NSAIDs), the Omeprazole versus Misoprostol for NSAID-induced Ulcer Management and the Acid Suppression Trial: Ranitidine versus Omeprazole for NSAID-associated Ulcer Treatment studies, concluded that omeprazole was superior to a subtherapeutic misoprostol or an ineffective dose of ranitidine for the endpoint, prevention of gastroduodenal ulcers in chronic NSAID users. Helicobacter pylori status was collected prospectively but was not reported. We report separate analyses for patients with unequivocal NSAID ulcers (H. pylori negative) and patients whose NSAID use was complicated by the presence of an active H. pylori infection. Omeprazole was superior to placebo for the prevention of ulcer recurrence in chronic NSAID users. However, omeprazole was not significantly better than a subtherapeutic dose of misoprostol for the prevention of gastroduodenal ulcers in chronic NSAID users. Misoprostol was superior to omeprazole for the prevention of gastric ulcers among those patients with unequivocal NSAID ulcers (8.2% vs 16.6%, respectively; P <0.05). Omeprazole was not statistically different from misoprostol for gastric ulcer prevention in those whose NSAID use was complicated by an active H. pylori infection. Ranitidine and omeprazole were also not statistically different for the prevention of unequivocal NSAID gastric ulcers (14.6% vs 11.6%, respectively; P = 0.56). That the Misoprostol Ulcer Complications Outcomes Safety Assessment (MUCOSA) trial found full-dose misoprostol to be more effective in ulcer prevention than it was in prevention of ulcer complications suggests that either many of the ulcer complications were related to H. pylori ulcers or that more antisecretory activity than can be provided with misoprostol is needed, or both. The question remains whether the combination of low-dose misoprostol plus an antisecretory drug (either an H(2)-receptor antagonist or a proton pump inhibitor) would provide superior results compared with either alone. That omeprazole was not superior to one half the dose of misoprostol used in the ulcer complication prevention, or MUCOSA, study indicates that it would not be prudent to suggest that ulcer prevention with omeprazole alone would be able to provide similar protection to misoprostol.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2001

Comparison of the Etest and the NCCLS-approved agar dilution method to detect metronidazole and clarithromycin resistant Helicobacter pylori.

Although the NCCLS has approved the agar dilution method as the test of choice for antimicrobial susceptibility testing of Helicobacter pylori, a critical evaluation of this method in clinical trials to detect antibiotic resistance has not been performed. This study compares the Etest and agar dilution methods for detection of metronidazole and clarithromycin resistance in clinical isolates of H. pylori. MIC data were gathered from US-based clinical trials. The Etest was performed on Mueller-Hinton sheep blood agar plates following incubation for 4 days under 12% CO(2). The agar dilution test was performed according to the recently approved NCCLS methodology using aged sheep blood in a Mueller-Hinton agar base. Metronidazole resistance as determined by Etest was significantly higher than that determined by agar dilution (39%; 690/1768 vs. 25. 1%; 367/1465)(P<0.01). Clarithromycin resistance as determined by Etest was higher than that determined by agar dilution, but was not significantly different (12.5%; 209/1671 vs. 10.6%; 150/1414)(P>0.5). Inter-patient metronidazole resistance showed that the MIC values for identical isolates tested by both methods were equivalent in 58% (109/188). Of the 42% with a >2log(2) difference in MIC values, 17. 6% had a change in susceptibility pattern. For clarithromycin, 71.4% (237/332) of the MIC values for identical isolates tested by both methods had equivalent MIC values. Of the MIC values with a >2log(2) difference in MIC values, only 3% showed a change in susceptibility pattern. Intra-patient variability, i.e. paired isolates from the same patient, was assessed only for metronidazole. Of the 1393 paired isolates tested by Etest, 38.8% were shown to be resistant. Almost 69% of the Etest MIC determinations were deemed equivalent and 16.7% had a change in susceptibility pattern. Of the 639 paired isolates tested by agar dilution, 23.9% were resistant to metronidazole. Almost 72% of the agar dilution MIC values were equivalent and 11.3% of the determinations had a change in susceptibility pattern. Clarithromycin resistance rates are similar, when determined by either test method. The Etest yields a significantly higher prevalence of metronidazole resistance among H. pylori compared with the agar dilution method and both methods yield discordant results, when isolates from different parts of the same stomach are compared. Neither method is reliable in determining metronidazole resistance in H. pylori.

Anti-Bacterial Agents↗
PubMed2001

Etiology of Crohn's disease: the role of Mycobacterium avium paratuberculosis.

Crohn's disease is a chronic inflammatory bowel disease characterized by transmural inflammation and granuloma formation. Several theories regarding the etiology of Crohn's disease have been proposed, one of which is infection with Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis), which causes a similar disease in animals, and is present in the human food chain. Considerable evidence supports the presence of M. paratuberculosis in the intestinal tissues of many patients with Crohn's disease including culture, detection of homologous mycobacterial DNA, detection of the mycobacterial insertion sequence IS900 by both PCR and in situ hybridization in tissues, and a serologic immune response to recombinant M. paratuberculosis antigens. Despite this evidence, and our personal belief that M. paratuberculosis is a cause of Crohn's disease, widespread acceptance of this hypothesis will require evidence that specific anti-mycobacterial chemotherapy will cure the disease.

Cell Wall↗
PubMed2001

Review article: Mycobacterium avium subsp. paratuberculosis as one cause of Crohn's disease.

A number of theories regarding the aetiology of Crohn's disease have been proposed. Diet, infections, other unidentified environmental factors and immune disregulation, all working under the influence of a genetic predisposition, have been viewed with suspicion. Many now believe that Crohn's disease is a syndrome caused by several aetiologies. The two leading theories are the infectious and autoimmune theories. The leading infectious candidate is Mycobacterium avium subspecies paratuberculosis (Mycobacterium paratuberculosis), the causative agent of Johne's disease, an inflammatory bowel disease in a variety of mammals including cattle, sheep, deer, bison, monkeys and chimpanzees. The evidence to support M. paratuberculosis infection as a cause of Crohn's disease is mounting rapidly. Technical advances have allowed the identification and/or isolation of M. paratuberculosis from a significantly higher proportion of Crohn's disease tissues than from controls. These methodologies include: (i) improved culture techniques; (ii) development of M. paratuberculosis-specific polymerase chain reaction assays; (iii) development of a novel in situ hybridization method; (iv) efficacy of macrolide and anti-mycobacterial drug therapies; and (v) discovery of Crohn's disease-specific seroreactivity against two specific M. paratuberculosis recombinant antigens. The causal role for M. paratuberculosis in Crohn's disease and correlation of infection with specific stratification(s) of the disorder need to be investigated. The data implicating Crohn's as an autoimmune disorder may be viewed in a manner that supports the mycobacterial theory. The mycobacterial theory and the autoimmune theory are complementary; the first deals with the aetiology of the disorder, the second deals with its pathogenesis. Combined therapies directed against a mycobacterial aetiology and inflammation may be the optimal treatment of the disease.

Animals↗