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B Bonaz

Publications and source records attributed to B Bonaz.

At least 19 recordsLinked to original sources
PubMed2005

[Factors associated with hyperhomocysteinemia in inflammatory bowel disease: prospective study in 81 patients].

BACKGROUND: A high prevalence (52%) of hyperhomocysteinemia is observed in Crohn disease (CD), however it is not well documented in ulcerative colitis (UC). Furthermore, in the different works studying hyperhomocysteinemia the associated factors are different. AIM: Prospective evaluation of hyperhomocysteinemia in inflammatory bowel disease (IBD) patients, of the risk factors and the determination of a potential risk of colorectal carcinoma in case of hyperhomocysteinemia. PATIENTS AND METHODS: IBD patients followed in our department were prospectively recruited between November 2003-September 2004. To be included patients should have passed a coloscopy in the two years. Patients with kidney failure or drugs supposed, to interfere with homocystéine metabolism (folates, vitamin B12, methotrexate) were excluded from the study. The following parameters were analysed: age, sex, clinical activity indexes (CDAI for Crohn disease and CAI for ulcerative colitis), length-extent and type of the disease (CD or UC), smoking, plasma homocystein concentration, folates and vitamin B12. RESULTS: Eighty-one patients (60 CD, 21 UC, mean age 43.8 +/- 17.3) were included, 30 had an active disease at inclusion and 16 were smokers. The prevalence of high homocystein concentration was 55.6%. In univariate analysis a low rate of folates was the only risk factor for a high homocystein concentration (74 vs. 52.8%; P = 0.018). Smoking was almost an associated factor. In multivariate analysis, a low rate of folate was the only risk factor of hyperhomocysteinemia, OR = 3.59 [1.27-10.17]. Five endoscopic lesions considered as precancerous were described; these patients had all a hyperhomocysteinemia. CONCLUSION: The prevalence of hyperhomocysteinemia is high in UC and in CD. A low folate rate is the only risk factor observed in our study. There is a possible link between colorectal cancer and hyperhomocysteinemia. A high Plasma homocystein concentration must be search in inflammatory bowel disease patients and a substitutive treatment of folates and vitamin B12 is necessary in case of hyperhomocysteinemia.

Adult↗
PubMed2005

6-tioguanine monitoring in steroid-dependent patients with inflammatory bowel diseases receiving azathioprine.

BACKGROUND: 6-Thioguanine (6-tioguanine) nucleotides are the active metabolites of azathioprine. AIM: The aim of the study was to evaluate the rate of clinical remission without steroids in steroid-dependent Crohn's disease and ulcerative colitis patients receiving azathioprine, the medium- and long-term efficacy and the predictive factors of clinical response when monitoring 6-tioguanine. METHODS: Steroid-dependent Crohn's disease and ulcerative colitis patients receiving either azathioprine or not (treated later with a daily dose of 2.5 mg/kg) were prospectively included. 6-tioguanine was monitored at 1 and 2 months and every 3 months thereafter for 1 year. The azathioprine dose was adapted to reach a 6-tioguanine level of >250 pmol/8 x 10(8) red blood cells. Thiopurine methyltransferase genotype/phenotype was evaluated in some patients. RESULTS: A total of 106 patients were prospectively included (70 Crohn's disease, 36 ulcerative colitis). The clinical remission rate without steroids in patients receiving azathioprine, in intention-to-treat analysis, was 72% and 59% at 6 and 12 months, respectively. The remission rate was significantly higher in patients with 6-tioguanine >250 pmol/8 x 10(8) RBC (86% and 69% at 6 and 12 months, respectively; P < 0.01). No significant difference was observed between Crohn's disease and ulcerative colitis patients whether treated by azathioprine or not on inclusion. In the univariate analysis, the absence of Crohn's disease stenosis, a 6-tioguanine level >250 pmol/8 x 10(8) RBC, and an increase of erythrocyte mean corpuscular volume were the factors predictive of a favourable clinical response. In the multivariate analysis, only a 6-tioguanine level of >250 pmol/8 x 10(8) red blood cells was a predictive factor of favourable clinical remission. CONCLUSIONS: Clinical remission without steroids is significantly more likely when monitoring 6-tioguanine so as to reach a level of >250 pmol/8 x 10(8) red blood cells in steroid-dependent Crohn's disease and ulcerative colitis patients receiving azathioprine (86% and 69% at 6 and 12 months, respectively).

Adolescent↗
PubMed2005

Symptomatic efficacy of beidellitic montmorillonite in irritable bowel syndrome: a randomized, controlled trial.

BACKGROUND: Beidellitic montmorillonite is a purified clay containing a double aluminium and magnesium silicate. AIM: To assess the efficacy and the safety of beidellitic montmorillonite (3 g, t.d. for 8 weeks) in patients with irritable bowel syndrome (IBS). METHODS: A multicentre, double-blind, placebo-controlled, randomized study with parallel groups, was performed in IBS patients selected according to ROME I criteria. Patients were included after a 1-week washout period to confirm that abdominal pain and/or discomfort was rated at least 2 on a 0-4 graded Likert scale. Patients were then randomized and stratified according to their predominant bowel habit profile into three groups. The use of rescue medication was allowed: polyethylene glycol 4000 (10-20 g/day) as a laxative agent in case of stool absence for three consecutive days, phloroglucinol (80 to a maximum of 320 mg/day) as a spasmolytic agent for no more than 8 days. The main end-point was the improvement of abdominal pain and/or discomfort by at least 1 point on the Likert scale. RESULTS: A total of 524 patients constituted the overall intent-to-treat population (ITT), 263 were assessed in the beidellitic montmorillonite group, i.e. 93 diarrhoea-predominant IBS (D-IBS), 83 constipation-predominant IBS (C-IBS), 87 alternating constipation/diarrhoea-IBS (A-IBS); 261 in the placebo group, i.e. 81 D-IBS, 92 C-IBS and 88 A-IBS. Initial analysis in the ITT population demonstrated a higher rate of success with beidellitic montmorillonite (51.7%) when compared with the placebo group (45.2%); however, the difference was not statistically significant. Improvement was significant in C-IBS both in ITT (beidellitic montmorillonite group = 49.4%, placebo group = 31.5%, P < 0.016) and per protocol populations (59.4% vs. 37.8%) (P < 0.01). The time to improvement of abdominal pain and/or discomfort (log Rank test) was also significantly in favour of beidellitic montmorillonite, (P < 0.04). The average number of stools per day was not different from baseline, either in all patients or in C-IBS patients. Spasmolytic and laxative agent intakes were not different between the two groups. Subjective evaluation by patients of treatment efficacy and visual analogue scale test of treatment efficacy by investigators were significantly better in the beidellitic montmorillonite group (P < 0.05). Tolerance of beidellitic montmorillonite was considered optimal without any significant adverse event. CONCLUSIONS: Although pain or discomfort was not significantly improved in the entire IBS population treated with beidellitic montmorillonite in comparison with placebo, this study demonstrates that beidellitic montmorillonite is efficient for C-IBS patients (P < 0.016). This effect of beidellitic montmorillonite on pain cannot be explained by changes in bowel habits. The efficacy of this well-tolerated therapy warrants further confirmatory therapeutic trials in C-IBS patients.

Abdominal Pain↗
PubMed2004

Effect of low-dose rabeprazole and omeprazole on gastric acidity: results of a double blind, randomized, placebo-controlled, three-way crossover study in healthy subjects.

BACKGROUND: The treatment of acid-related symptoms requires rapid and consistent acid suppression, especially with on-demand regimens. AIM: To compare the antisecretory activity of low-dose rabeprazole and omeprazole in healthy, Helicobacter pylori-negative subjects. METHODS: In this randomized, double-blind, placebo-controlled, three-way crossover study, 27 volunteers were given rabeprazole 10 mg, omeprazole 10 mg, or placebo once daily for 7 days with a 10-14-day washout between treatments. Intragastric pH was monitored for 24-h on days 1 and 7 of each treatment. RESULTS: Median gastric pH was significantly higher with rabeprazole than with omeprazole or placebo: day 1: 2.3, 1.4 and 1.3, respectively (P = 0.0056, rabeprazole vs. omeprazole; P < 0.0001, rabeprazole vs. placebo); day 7: 3.7, 2.2 and 1.3, respectively (P = 0.0016 rabeprazole vs. omeprazole; P < 0.0001, rabeprazole vs. placebo). Time with gastric pH above 4 was significantly higher with rabeprazole than with omeprazole: day 1, 5.8 h vs. 3.7 h, respectively (P < 0.02); day 7, 10.5 h vs. 4.6 h, respectively (P = 0.0008). CONCLUSIONS: Rabeprazole 10 mg provides more rapid acid inhibition compared with omeprazole 10 mg. After 7 days, the time with pH above 4 is more than doubled with rabeprazole 10 mg vs. omeprazole 10 mg.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

Drug interaction between infliximab and azathioprine in patients with Crohn's disease.

BACKGROUND: A drug interaction has been observed between infliximab and methotrexate in rheumatoid arthritis. AIM: To look for an interaction between infliximab and azathioprine in Crohn's disease patients using the active metabolites of azathioprine: 6-tioguanine nucleotides. METHODS: Patients receiving azathioprine who required infliximab for ileo-colonic or ano-perineal Crohn's disease were recruited prospectively. 6-tioguanine nucleotide levels were evaluated before infusion, within 1-3 weeks after the first infusion and 3 months after the first infusion. The clinical outcome was evaluated by the Harvey-Bradshaw index or the closure of ano-perineal fistulas. RESULTS: Thirty-two patients were included (17 received one infusion and 15 received three infusions). The mean 6-tioguanine nucleotide level was comparable before and 3 months after the first infusion, but a significant increase was observed within 1-3 weeks after the first infusion (P < 0.001). In parallel, a significant decrease in leucocyte count and increase in mean corpuscular volume were observed; these modifications were normalized 3 months after infusion. An increase in 6-tioguanine nucleotide level of greater than 400 pmol/8 x 108 erythrocytes was strongly related to good tolerance and a favourable response to infliximab, with a predictive value of 100%. CONCLUSIONS: This prospective study provides evidence for a drug interaction between azathioprine and infliximab.

Adolescent↗
PubMed2003

Tioguanine in patients with Crohn's disease intolerant or resistant to azathioprine/mercaptopurine.

BACKGROUND: Tioguanine (TG) is an antimetabolite which may be regarded as an alternative to azathioprine (AZA)/mercaptopurine (MP) in patients with inflammatory bowel diseases. AIMS: : To evaluate the tolerance and efficacy of TG in patients with Crohn's disease, intolerant or resistant to AZA/MP. METHODS: An open prospective study was made on Crohn's disease patients treated with TG. Intolerance to AZA/MP was defined as a reaction occurring within 1 month after introduction of AZA/MP, including pancreatitis, abdominal pain, fever, arthralgia, myalgia, cutaneous rash, fatigue, alopecia, hepatitis and digestive intolerance. Resistance to AZA/MP was defined as the persistence of activity after at least 3 months of AZA/MP therapy. RESULTS: Forty-nine Crohn's disease patients (36 women, 13 men; intolerance: n = 39; resistance: n= 10) were treated with TG (20 mg/day). Clinical pancreatitis did not recur under TG. Five patients (10%) had to stop TG due to intolerant reactions observed 13-21 days after TG was started. No haematological side-effects were observed under TG. The probability of clinical remission without corticosteroids or infliximab at 6 and 12 months was 46% and 79%, respectively, in the 40 patients with active disease at baseline. The probability of clinical relapse during maintenance TG therapy at 6 and 12 months was 29% and 53%, respectively, in the 28 patients in remission at baseline or who had achieved remission on TG. CONCLUSIONS: TG is a possible alternative treatment in Crohn's disease patients, intolerant (especially for pancreatitis) or resistant to AZA/MP.

Adult↗
PubMed2003

Visceral sensitivity perturbation integration in the brain-gut axis in functional digestive disorders.

Chronic abdominal pain is the most distressing symptom in patients with functional digestive disorders (FDD). IBS is the most common gastrointestinal disorder seen in primary care and gastroenterology practice. IBS is a functional bowel disorder in which abdominal pain is associated with defaecation or a change in bowel habit, with features of disordered defecation and with distension. The underlying pathophysiology of IBS is unknown but a chronic visceral hyperalgesia, in the absence of detectable organic disease, is implicated. The exact location of abnormality of visceral pain processing is not known. Theories of its etiology have range widely from the original view that the disease represents a primary disturbance of gut mucosa to emerging conception of the syndrome as emanating from a complex disordered interaction between the digestive and nervous systems. Several lines of evidence suggest a strong modulatory or etiologic role of the central nervous system in the pathophysiology of IBS. A major advance in the understanding of the central mechanisms of pain processing has evolved from application of functional imaging techniques, as represented by positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). In humans, multiple components are involved in somato-visceral pain processings, including sensory-discriminative components, affective components, and cognitive components. Silverman et al, using PET, were the first to explore neural correlates of abdominal pain induced by rectal distension. If healthy subjects activated the ACC, the IBS patients did not while they presented an activation of the left PFC. These findings were consistent with an IBS model that includes both the exaggerated activation of a vigilance network (dorsolateral PFC) and a failure in pain inhibition network anterior cingulate cortex (ACC). In contrast, Mertz et al., using fMRI, observed that pain led to a greater activation of the ACC than did non-painful stimuli thus arguing for an up-regulation of afferent sensitivity to pain. Using fMRI, we also characterized cerebral loci activated by a rectal distension in healthy volunteers. The activation patterns presented a strong similarity with the central processing of somatic pain. In contrast, in a women predominant population of IBS patients, we did not observed any neuronal activation in locations activated in healthy volunteers (ACC, dorsolateral PFC) while a significant deactivation was observed in the IC and in the amygdala, a limbic structure with a role to assign emotional significance to a current experience related to anxiety and fear. Brain imaging techniques thus appear as useful tools to characterize normal and abnormal brain processing of visceral pain in patients with FDD. Reversal effects of chemical compounds targeting these abnormalities either at a peripheral or a central level should be of interest.

Animals↗
PubMed2002

Relationship between acid reflux episodes and gastroesophageal reflux symptoms is very inconstant.

In this prospective study 244 consecutive patients presenting with typical and chronic signs of gastroesophageal reflux were included. Conventional 24-hr esophageal pH monitoring was carried out to establish the symptom association probability, the concordance index, and the symptom sensitivity index. The symptom association probability could be calculated in 110 patients (45%). Two groups were identified: group 1 had normal duration of esophageal acid exposure; subgroup la (nonsignificant symptom association probability) included 39 patients (35.5%) and subgroup lb (significant symptom association probability) included 24 patients (21.8%); group 2 had abnormal duration of esophageal acid exposure; subgroup 2a (nonsignificant symptom association probability) included 21 patients (19.1%) and subgroup 2b (significant symptom association probability) included 26 patients (23.6%). In all, 56.6% of the patients presented typical symptoms of reflux not directly determined by one or repeated acid reflux episodes. The correlation between symptom association probability and the symptom sensitivity index allows for more accurate determination of esophageal acid sensitivity (subgroups lb and 2b).

Adolescent↗
PubMed2002

Central processing of rectal pain in patients with irritable bowel syndrome: an fMRI study.

OBJECTIVES: In healthy subjects, the neural correlates of visceral pain bear much similarity with the correlates of somatic pain. In patients with irritable bowel syndrome, the central nervous system is believed to play a strong modulatory or etiological role in the pathophysiology of the disease. We hypothesize that this role must be reflected in aberrations of central functional responses to noxious visceral stimulation in these patients. To verify this hypothesis, we have induced transient rectal pain in patients and assessed the functional responses of the brain by means of functional magnetic resonance imaging. METHODS: Twelve right-handed patients (11 female) were examined. Functional imaging (1.5 T) was performed following a block paradigm, alternating epochs with and without noxious stimulation of the rectum. Rectal pain was induced by inflating a latex balloon. Whole-brain coverage was achieved by means of echo-planar magnetic resonance acquisition. RESULTS: A strong variability of the individual responses to rectal pain was found in patients with irritable bowel syndrome. Significant activations were found in only two patients, and group analysis did not reveal significant activations. In contrast, all patients exhibited significant deactivations. Group analysis revealed significant deactivations within the right insula, the right amygdala, and the right striatum. CONCLUSIONS: This study reveals aberrant functional responses to noxious rectal stimulation in patients with irritable bowel syndrome. Those results add grounds to the hypothesis that the central nervous system plays a significant role in the pathophysiology of this syndrome.

Adult↗
PubMed2000

Genotypic analysis of thiopurine S-methyltransferase in patients with Crohn's disease and severe myelosuppression during azathioprine therapy.

BACKGROUND & AIMS: Myelosuppression in patients with Crohn's disease (CD) treated with azathioprine has been attributed to low activity of thiopurine S-methyltransferase (TPMT). Allelic variants of the TPMT gene responsible for changes in the enzyme activity have been characterized. We investigated the distribution of mutant alleles associated with TPMT deficiency in patients with CD and myelosuppression during azathioprine/6-mercaptopurine therapy. METHODS: Forty-one patients with CD were included. They developed leukopenia or thrombocytopenia during azathioprine or 6-mercaptopurine treatment. Polymerase chain reaction-based methods were used to search for mutations associated with TPMT deficiency. RESULTS: Four patients (10%) had 2 mutant alleles associated with TPMT deficiency, 7 (17%) had 1 mutant allele, and 30 (73%) had no known TPMT mutation. The delay between administration of the drug and occurrence of bone marrow toxicity was less than 1.5 months in the 4 patients with 2 mutant alleles, and ranged from 1 to 18 months in patients with 1 mutant allele and from 0.5 to 87 months in patients with normal genotype. CONCLUSIONS: Twenty-seven percent of patients with CD and myelosuppression during azathioprine therapy had mutant alleles of the TPMT gene associated with enzyme deficiency. Myelosuppression is more often caused by other factors. Continued monitoring of blood cell counts remains mandatory in patients treated with azathioprine.

Adolescent↗
PubMed2000

Fedotozine, a kappa-opioid agonist, prevents spinal and supra-spinal Fos expression induced by a noxious visceral stimulus in the rat.

Fedotozine, a kappa opioid agonist, reverses digestive ileus caused by acetic acid (AA)-induced visceral pain in rats. The aims of this study were: to map, in conscious rats, central pathways activated by AA using Fos as a marker of neuronal activation; to characterize primary afferent fibres involved in this activation; and to investigate the effect of fedotozine on AA-induced Fos expression. AA (0.6%; 10 mL kg-1) was injected i.p. in conscious rats either untreated; pretreated 14 days before with capsaicin; pretreated 20 min previously with fedotozine; or pretreated 2 h prior to fedotozine with the kappa-antagonist nor-binaltorphimine (nor-BNI). Controls received the vehicle alone. 60 min after injection of AA, rats were processed for Fos immunohistochemistry. Visceral pain was assessed by counting abdominal cramps. AA induced Fos in the thoraco-lumbar spinal cord (laminae I, V, VII and X) and numerous brain structures such as the nucleus tractus solitarius, and paraventricular nucleus (PVN) of the hypothalamus, whereas almost no Fos labelling was observed in controls. Capsaicin pretreatment blocked AA-induced Fos in all structures tested. Fedotozine significantly decreased AA-induced abdominal cramps and Fos immunoreactivity in the spinal cord and PVN, this effect being reversed by nor-BNI pretreatment. AA induces Fos in the spinal cord and numerous brain nucuei, some of which are involved in the control of digestive motility in rats. This effect is mediated through capsaicin-sensitive afferent fibres and prevented by fedotozine most likely through a peripheral action on visceral afferents.

Abdominal Pain↗
PubMed1999

[Evaluation of esophageal motility disorders triggered by ingestion of solids in the case of non-obstructive dysphagia].

UNLABELLED: The aim of this study was to define the normal manometric pattern of esophageal motility in response to food ingestion and to evaluate the contribution of esophageal manometry in the management of patients complaining of functional dysphagia. PATIENTS AND METHODS: Twenty-one healthy volunteers and 25 consecutive patients complaining of functional dysphagia with normal conventional esophageal manometry were included in this prospective study. An event marker was used to study the relationship between dysphagia and motility events. RESULTS: Twenty-two out of 25 patients (88%) reported dysphagia during esophageal manometry with food ingestion, while none complained of dysphagia during conventional esophageal manometry. Significantly, food ingestion induced in healthy volunteers and in patients: an increase in the amplitude and duration of esophageal body peristaltic contractions, and a decrease in their propagation speed; an increase in the basal pressure and a decrease in the relaxation percentage of the lower esophageal sphincter during deglutition. The percentage of solid swallows with one or several of the 7 abnormal motility patterns studied prospectively was significantly higher among patients (53.7%) than among healthy volunteers (4.3%) (P < 0.0001); it was also significantly higher among patients during swallows with dysphagia (70.1%) than without dysphagia (33.6%) (P < 0.0001). CONCLUSION: Esophageal manometry with food ingestion is an effective means of defining abnormal motility patterns and their relationship with dysphagia during functional dysphagia.

Adult↗
PubMed1998

Effect of a chronic stress on CRF neuronal activity and expression of its type 1 receptor in the rat brain.

The purpose of this study was to compare the effect of an acute versus a chronic immobilization stress on the genetic expression of c-fos and corticotropin-releasing factor type 1 receptor (CRF1 receptor) in the paraventricular nucleus (PVN) of the rat hypothalamus. Male Sprague-Dawley rats were exposed to either a single 90-min immobilization stress or the same session for 11 consecutive days. Animals were deeply anesthetized before (control); immediately, 1.5, 3, 6, or 12 h after the acute stress; or after the last session of the repeated exposures to immobilization. Coronal frozen sections (30 micrometers) of the brains were cut and mRNAs encoding the rat c-fos and CRF1 receptor were assayed by in situ hybridization histochemistry using 35S-labeled riboprobes. Localization of these transcripts within PVN CRF-immunoreactive (ir) neurons was also determined. The expression of the mRNA encoding either c-fos or CRF1 receptor was barely detectable to low in the PVN of control animals, but the acute stress session induced a robust signal for both transcripts in this endocrine nucleus. Numerous CRF-ir neurons were positive for the gene encoding either c-fos or CRF1 receptor in the PVN of acutely stressed animals. In contrast, the PVN of chronically stressed animals displayed a significantly lower CRF1 receptor mRNA signal after the last stress session. In these animals, stress-induced transcription of c-fos mRNA occurred in the magnocellular PVN 90 min after the end of the last stress session but only a low signal was detected in the parvocellular division. Moreover, very few CRF-ir neurons of the PVN expressed either the CRF1 receptor or c-fos transcript in chronically stressed rats. These data provide evidence for an adaptive cellular mechanism involving an attenuated action of CRF within the PVN in response to repeated homotypic stress exposures.

Animals↗
PubMed1997

Corticotropin-releasing factor and systemic capsaicin-sensitive afferents are involved in abdominal surgery-induced Fos expression in the paraventricular nucleus of the hypothalamus.

We previously reported that abdominal surgery induces Fos expression in specific hypothalamic and medullary nuclei and also causes gastric stasis. The gastric ileus is reduced by systemic capsaicin and abolished by central injection of corticotropin-releasing factor (CRF) antagonist. We studied the influence of systemic capsaicin and intracerebroventricular (i.c.v.) injection of the CRF antagonist, alpha-helical CRF9-41, on Fos expression in the brain 1 h after abdominal surgery in conscious rats using immunocytochemical detection. In control groups (vehicle s.c. or i.c.v.), abdominal surgery (laparotomy with cecal manipulation) performed under 7-8 min of enflurane anesthesia induced Fos staining in neurons of the spinal trigeminal, C1/A1 group, ventrolateral medulla, central amygdala, parabrachial nucleus, cuneate nucleus, nucleus tractus solitarii (NTS), paraventricular nucleus of the hypothalamus (PVN) and supraoptic nucleus (SON). Capsaicin (125 mg/kg s.c., 2 weeks before) or alpha-helical CRF9-41 (50 microg i.c.v., before surgery) reduced the number of Fos-positive cells by 50% in the PVN while not modifying the number of Fos-labelled cells in the other nuclei. These results indicate that capsaicin-sensitive primary afferents and brain CRF receptors are part of the pathways and biochemical coding through which abdominal surgery activates PVN neurons 1 h post surgery.

Abdomen↗
PubMed1997

Association between myelodysplastic syndromes and inflammatory bowel diseases. Report of seven new cases and review of the literature.

We report seven patients with both myelodysplastic syndrome (MDS) and inflammatory bowel disease (IBD): Crohn's disease in six cases, ulcerative colitis in one case. We describe their characteristics, and those of 10 previously published similar cases are presented here. Median age at diagnosis of IBD (61 years) was high, as compared to the usual age at diagnosis of IBD. IBD was diagnosed first in nine cases, MDS first in one patient, and both diseases were diagnosed simultaneously in seven cases. Concerning IBD, there was a strong predominance of Crohn's disease (15/17 cases), with an unusually high frequency of colonic involvement (11/15 cases). MDS, in 12/17 cases, showed no excess of marrow blasts. Cytogenetic analysis was abnormal in five of the 13 evaluable cases. These observations suggest that the association between MDS and IBD may not be fortuitous in some cases, and that, in particular, patients with IBD and anemia of nonobvious origin should be evaluated for MDS. The pathogenesis of those associations, however, remains unclear.

Adult↗