A prospective cohort study to determine the relationship between serum infliximab concentration and efficacy in patients with luminal Crohn's disease.

BACKGROUND: Patients with Crohn's disease (CD) may experience disease relapse on maintenance infliximab. Anti-drug antibodies likely contribute to loss of response, and serum infliximab levels likely correlate with efficacy. AIM: To prospectively evaluate the relationship between trough serum infliximab concentration and disease activity. METHODS: Adult patients (N = 327) with a diagnosis of CD who had received at least five consecutive infliximab infusions and who planned to receive at least two additional infusions were enrolled. The Crohn's Disease Activity Index (CDAI), serum infliximab, C-reactive protein (CRP) and antibodies-to-infliximab (ATI) were assessed at baseline, week 4 and week 8. Receiver operating characteristic (ROC) analysis examined the relationship between infliximab concentrations and disease activity. RESULTS: The mean CDAI score, which decreased 1.05 points between infusions, did not correlate with the mean change in trough infliximab concentration (+0.39 µg/mL; r = 0.099, P = 0.083), but was associated with the mean change in CRP concentration (r = 0.19, P < 0.001). Trough infliximab concentrations below 2.8-4.6 µg/mL best predicted a ≥ 70 point increase in the CDAI between infusions, and those below 2.7-2.8 µg/mL best predicted CRP >5 mg/mL at the second infusion. ATI at either visit decreased the proportion of patients with therapeutic infliximab trough levels compared with patients who were ATI negative (17.5% vs. 77.3% at visit 1 and 13.8% vs. 75.6% at visit 3; P < 0.001 for both comparisons). CONCLUSIONS: This prospective study confirms the relationship between trough infliximab concentrations, inflammation and antibodies-to-infliximab. Infliximab trough concentrations below 3 µg/mL may increase the likelihood of symptoms and inflammation (ClinicalTrials.gov identifier: NCT00676988).

Review article: a clinician's guide for therapeutic drug monitoring of infliximab in inflammatory bowel disease.

BACKGROUND: Tumour necrosis factor (TNF)-antagonists have an established role in the treatment of inflammatory bowel diseases (IBDs), however, subtherapeutic drug levels and the formation of anti-drug antibodies (ADAs) may decrease their efficacy. AIM: The evidence supporting the use of therapeutic drug monitoring (TDM) based clinical algorithms for infliximab (IFX) and their role in clinical practice will be discussed. METHODS: The literature was reviewed to identify relevant articles on the measurement of IFX levels and antibodies-to-infliximab. RESULTS: Treatment algorithms for IBD have evolved from episodic monotherapy used in patients refractory to all other treatments, to long-term combination therapy initiated early in the disease course. Improved remission rates have been observed with this paradigm shift, nevertheless many patients ultimately lose response to therapy. Although empiric dose optimization or switching agents constitute the current standard of care for secondary failure, these interventions have not been applied in an evidence-based manner and are probably not cost-effective. Multiple TDM-based algorithms have been developed to identify patients that may benefit from measurement of IFX and ADA levels to guide adjustments to therapy. CONCLUSIONS: Therapeutic drug monitoring offers a rational approach to the management of secondary failure to IFX. This concept has gained momentum based on evidence from case series, cohort studies and post-hoc analyses of randomised controlled trials.

Relationship between social support and autonomic function during a stress protocol in ulcerative colitis patients in remission.

BACKGROUND: The relationship of psychological stress to relapse in ulcerative colitis (UC) is inconsistent. This may be due to a failure to identify patient characteristics, such as social support, which moderate the transduction of stress from the central nervous system to the immune system. In this study we tested the hypothesis that social support enhances parasympathetic modulation of heart rate in UC. METHODS: An indirect measure of autonomic function (heart rate variability; HRV) was measured in 108 patients with UC in remission during a standard protocol involving periods of stress, paced breathing, and relaxation. Social support was measured with the Social Support Questionnaire. RESULTS: After controlling for age, which is strongly related to HRV, both satisfaction with social support (F = 5.7, significance = 0.002) and its interaction with age (F = 7.8, significance <0.001) were associated with high-frequency HRV, which measures parasympathetic modulation of heart rate. Social support was associated with higher levels of high-frequency HRV at almost all points in the stress protocol. Neither age nor social support was associated with differences in the LF/HF ratio, which measures sympathetic modulation of heart rate. CONCLUSIONS: Social support is related to parasympathetic activity in UC. Given previous evidence of an antiinflammatory role for the parasympathetic nervous system, this suggests that autonomic function could serve as a mediating link between social support and reduced inflammatory activity.

Trough serum infliximab: a predictive factor of clinical outcome for infliximab treatment in acute ulcerative colitis.

BACKGROUND AND AIMS: Antibodies to infliximab reduce serum infliximab with loss of clinical benefit, but undetectable trough serum concentrations of infliximab may occur without antibody formation. The relationship between trough serum infliximab and clinical outcomes was evaluated in acute ulcerative colitis. METHODS: In a cohort of 115 patients with ulcerative colitis treated with three-dose induction followed by scheduled maintenance infliximab, rates of clinical remission, colectomy, antibodies to infliximab and trough serum infliximab were determined. RESULTS: Rates of remission were 32% at week 10 and 37% at week 54. Colectomy occurred in 40% of patients, at a median of 5.3 (IQR 1.9-12.1) months. Detectable trough serum infliximab was present in 39% of patients and, among patients with undetectable infliximab, 41% were antibody positive and 20% were antibody negative. For antibody-positive and antibody-negative patients, rates of remission (18% vs 14%), endoscopic improvement (25% vs 35%) and colectomy (52% vs 59%) were not different. A detectable serum infliximab was associated with higher rates of remission (69% vs 15%; p<0.001) and endoscopic improvement (76% vs 28%, p<0.001). An undetectable serum infliximab predicted an increased risk for colectomy (55% vs 7%, OR 9.3; 95% CI 2.9 to 29.9; p<0.001). Concurrent immunosuppression was not associated with clinical outcomes. CONCLUSIONS: For patients with ulcerative colitis treated with infliximab, a detectable trough serum infliximab predicts clinical remission, endoscopic improvement and a lower risk for colectomy. An undetectable trough serum infliximab, irrespective of antibody status, is associated with less favourable outcomes.

Review and clinical perspectives for the use of infliximab in ulcerative colitis.

Infliximab is a chimeric, monoclonal anti-tumour necrosis factor-alpha antibody. It has been previously demonstrated to be an effective treatment for patients with Crohn's disease who do not achieve the desired response with conventional treatments. Although the etiology of ulcerative colitis (UC) differs from that of Crohn's disease, randomized controlled trials have demonstrated that infliximab is also beneficial for the treatment of moderate to severe UC in patients who are either intolerant of or refractory to immunosuppressant agents or steroids, or those who are steroid-dependent. A review of the literature is followed by practical recommendations regarding infliximab that address the needs of clinicians and UC patients. Where there is a lack of evidence-based information, the expert panel provides its combined opinion derived from the members' clinical experiences.

The impact of ulcerative colitis is greater in unmarried and young patients.

GOALS: To determine whether the perceived impact of ulcerative colitis (UC) on activities of living (illness intrusiveness) is greater for people who are not living in a married or common-law relationship. BACKGROUND: In general, social and occupational achievement is not greatly impaired by UC, yet patients, especially young adults, often have interpersonal concerns. METHODS: One hundred fifty-five outpatients with UC were assessed for disease activity, and completed self-reports of marital status, income, social support and illness intrusiveness. RESULTS: Fifty-one patients (32.9%) were single, separated or divorced, and 104 patients (67.1%) were married or in common-law relationships. Compared with those who were married or in common-law relationships, single or separated patients were younger, had a lower household income, had lived with UC for fewer years and were less satisfied with social support. Among 135 patients in remission, marital status was significantly associated with illness intrusiveness, controlling for age, income and perceived social support (F=5.73; P=0.02). Low social support (F=4.94; P=0.03) and younger age (F=7.24; P=0.008) were independently associated with illness intrusiveness. Single patients in remission reported illness intrusiveness of similar severity to that reported by patients with active disease. CONCLUSIONS: The perceived impact of UC on the lives of patients is greater in those who are not married or living in common-law relationships. Youth, single status and lower social support commonly coexist, and exert additive effects on the functional impact of UC. Resources to improve social support should be directed toward this group of patients.

Eruptive tufted angiomas in a patient with Crohn's disease.

Angioblastoma is a rare, benign vascular tumour composed of undifferentiated mesenchymal cells with a tendency to form lumina. This entity was first described by Nakagawa in 1949 as angioblastoma, and Wilson Jones was the first to use the term "tufted angioma" in 1976. Tufted angiomas usually occur in infancy and spread slowly. This report describes lesions from the right side of the forehead, forearms, and thighs of a 24 year old man with a four year history of Crohn's disease, who was receiving infliximab in addition to long standing azathioprine and ciprofloxacillin. He developed numerous small itchy erythematous vascular appearing papules, which on histological examination resembled tufted angiomas, showing the classic "cannon ball" appearance. The lesions regressed within three months. This case may represent an eruptive acquired tufted angioma in which immunosuppression or drug induced modification of angiogenesis played a role in its development and regression. One previous case of eruptive tufted angioma has been reported in an immunosuppressed patient.

Diagnostic misclassification reduces the ability to detect linkage in inflammatory bowel disease genetic studies.

BACKGROUND: Linkage data have now identified several inflammatory bowel disease (IBD) susceptibility loci but these data have not been consistently replicated in independent studies. One potential explanation for this is the possibility that patients enrolled in such studies may have been erroneously classified with respect to their diagnosis. AIMS: To determine the rate and type of misclassification in a large population of individuals referred for participation in an IBD genetics study and to examine the effect of diagnostic misclassification on the power to detect linkage. METHODS: The medical records of 1096 patients entered into an IBD genetics programme were reviewed using standardised diagnostic criteria. The original patient reported diagnoses were changed, if necessary, based on review, and the reasons for the change in diagnosis were recorded. To evaluate the effect of misclassification on linkage results, simulations were created with Gensim and analysed using Genehunter to evaluate a model for IBD inheritance. RESULTS: Sixty eight of 1096 (6.2%) individuals had a change in diagnosis from that originally reported. The majority of changes were patients with either Crohn's disease or ulcerative colitis who were determined not to have IBD at all. The principal reasons for changes to the original diagnosis were discordance between the patients' subjective reports of diagnosis and actual clinical history, endoscopic, or pathological results; a change in disease pattern over time; and insufficient information available to confirm the original diagnosis. A 10% misclassification rate resulted in 28.4% and 40.2% loss of power to detect a true linkage when using a statistical model for a presumed IBD locus with lambda(s) values of 1.8 and 1.3, respectively. CONCLUSIONS: Diagnostic misclassification occurs in patients enrolled in IBD genetic studies and frequently involves assigning the diagnosis of IBD to non-affected individuals. Even low rates of diagnostic misclassification can lead to significant loss of power to detect a true linkage, particularly for loci with modest effects as are likely to be found in IBD.

Genetic variation in the 5q31 cytokine gene cluster confers susceptibility to Crohn disease.

Linkage disequilibrium (LD) mapping provides a powerful method for fine-structure localization of rare disease genes, but has not yet been widely applied to common disease. We sought to design a systematic approach for LD mapping and apply it to the localization of a gene (IBD5) conferring susceptibility to Crohn disease. The key issues are: (i) to detect a significant LD signal (ii) to rigorously bound the critical region and (iii) to identify the causal genetic variant within this region. We previously mapped the IBD5 locus to a large region spanning 18 cM of chromosome 5q31 (P<10(-4)). Using dense genetic maps of microsatellite markers and single-nucleotide polymorphisms (SNPs) across the entire region, we found strong evidence of LD. We bound the region to a common haplotype spanning 250 kb that shows strong association with the disease (P< 2 x 10(-7)) and contains the cytokine gene cluster. This finding provides overwhelming evidence that a specific common haplotype of the cytokine region in 5q31 confers susceptibility to Crohn disease. However, genetic evidence alone is not sufficient to identify the causal mutation within this region, as strong LD across the region results in multiple SNPs having equivalent genetic evidence-each consistent with the expected properties of the IBD5 locus. These results have important implications for Crohn disease in particular and LD mapping in general.

Concerns of patients with inflammatory bowel disease: results from a clinical population.

OBJECTIVE: The impact of chronic illness is influenced not just by physical symptoms but also by psychosocial factors. The aim of this study was to determine the concerns of inflammatory bowel disease (IBD) patients in a clinical sample, if concerns differ between patients from varied clinical and demographic variables, and if concerns influence well-being beyond the influence of physical symptoms. METHODS: Subjects (n = 259) completed a validated measure of concerns specific to IBD and provided demographic and disease-related information. RESULTS: The most intense concerns involved both physical (e.g., energy level) and psychosocial issues (e.g., achieving full potential). There were numerous differences in disease concerns based on ability to work but none based on disease duration. Factor analysis yielded three indices: body image and interpersonal concerns, general physical impact, and disease stigma. Age and education only affected certain concern indices in subgroups of patients. Greater concerns negatively influenced well-being beyond the influence of physical symptoms. CONCLUSION: Psychosocial factors, in addition to physical symptoms, play an important role on the impact of illness in patients with IBD.

Carrier rate of APC I1307K is not increased in inflammatory bowel disease patients of Ashkenazi Jewish origin.

Colorectal cancer (CRC) occurs with an increased incidence in individuals with chronic inflammatory bowel disease (IBD) of the colon. Recent data suggest that a family history of colorectal cancer is an independent risk factor for CRC in IBD, an observation that implies that genetic factors are relevant to the development of CRC in this context. Among the genetic defects associated with CRC, the APC I1307K mutation has been detected nearly exclusively in individuals of Ashkenazi Jewish (AJ) origin, occurring in 6%-7% of the AJ general population and in 10%-28% of AJ with a either a personal or family history of CRC or adenomatous polyps. These findings, together with the increased incidence of IBD in AJ, prompted the current analysis of the contribution of the APC I1307K variant of CRC in AJ IBD patients. APC I1307K carrier frequencies were determined in 306 AJ individuals affected with IBD and 308 of their unaffected relatives ascertained from a family collection obtained for the identification of IBD susceptibility genes. Prevalence of the I1307K variant was not significantly different among individuals with IBD, Crohn's disease, ulcerative colitis, and unaffected relatives (6.9%, 7.6%, 4.7%, and 6.2%, respectively), and the mutation was detected in only one of five IBD-affected individuals with a diagnosis of CRC. These results reveal that IBD patients of AJ origin carry the APC I1307K variant at the same rate as individuals within the general AJ population. Lack of an increased APC I1307K carrier rate suggests that this mutation does not account for the increased CRC susceptibility associated with IBD.

Somatostatin receptor subtype-5 mediates inhibition of peptide YY secretion from rat intestinal cultures.

Somatostatin-14 (S-14) and somatostatin-28 (S-28) bind to five distinct membrane receptors (SSTRs), but S-28 has higher affinity for SSTR-5. Whether S-28 acting through SSTR-5 regulates inhibition of peptide YY (PYY) secretion was tested in fetal rat intestinal cell cultures. S-28 and S-14 caused dose-dependent inhibition of PYY secretion stimulated by gastrin-releasing peptide, but S-28 was more potent than S-14 (EC(50) 0.04 vs. 13.2 nM). PYY was inhibited by two analogs with affinity for SSTR-5, BIM-23268 and BIM-23052, more potently than S-14 and as effectively as S-28. The SSTR-5 analog L-362855 suppressed PYY equivalent only to S-14, but the structurally related peptide L-372588 (Phe to Tyr at position 2) was equipotent to S-28, whereas L-372587 (Phe to Tyr at position 7) caused no inhibition. An SSTR-2 analog decreased PYY secretion similar to S-14, and an SSTR-3 analog was ineffective. PYY secretion stimulated by phorbol 12-myristate 13-acetate and by forskolin was also more potently suppressed by S-28 and the octapeptide SSTR-5 analogs. The results indicate that S-28 mediates inhibition of gastrin-releasing peptide-stimulated PYY secretion through activation of SSTR-5 and includes suppression of cAMP- and protein kinase C-dependent pathways. Substitution of a single hydroxyl group confers differences in SSTR-5 agonist properties, suggesting region specificity for the intrinsic activity of this receptor subtype.

Quality of life rapidly improves with budesonide therapy for active Crohn's disease. Canadian Inflammatory Bowel Disease Study Group.

Our aims were to assess the impact on health-related quality of life (HRQOL) of a controlled ileal release (CIR) formulation of budesonide in active Crohn's disease (CD) and further define the role of HRQOL, using the Inflammatory Bowel Disease Questionnaire (IBDQ), in assessing outcome in CD. A randomized trial was conducted in 258 patients with active ileal or ileocecal CD. Budesonide CIR 1.5 mg, 4.5 mg, 7.5 mg, or placebo was given b.i.d. for 8 weeks. IBDQ score changes were compared among groups. Correlations for IBDQ and Crohn's Disease Activity Index (CDAI) scores were calculated. Mean IBDQ scores improved significantly over placebo by 2 weeks in budesonide 15 mg (155+/-38; p = 0.006) and 9 mg groups (157+/-33; p = 0.0002). Bowel, systemic, social, and emotional subscores were also significantly better (p < 0.002) at 2 and 8 weeks in the 9 mg group. Improved HRQOL scores correlated well with decreased CDAI (-0.8 < r < -0.4). Average per item change in IBDQ at remission was 1.17 to 1.48. Prior surgery (p < 0.005) or current smoker (p < 0.05) status predicted poorer initial HRQOL but not response. Budesonide CIR 9 or 15 mg/day rapidly and significantly improved HRQOL in active CD.

A comparison of methotrexate with placebo for the maintenance of remission in Crohn's disease. North American Crohn's Study Group Investigators.

BACKGROUND: Patients with Crohn's disease often have relapses. Better treatments are needed for the maintenance of remission. Although methotrexate is an effective short-term treatment for Crohn's disease, its role in maintaining remissions is not known. METHODS: We conducted a double-blind, placebo-controlled, multicenter study of patients with chronically active Crohn's disease who had entered remission after 16 to 24 weeks of treatment with 25 mg of methotrexate given intramuscularly once weekly. Patients were randomly assigned to receive either methotrexate at a dose of 15 mg intramuscularly once weekly or placebo for 40 weeks. No other treatments for Crohn's disease were permitted. We compared the efficacy of treatment by analyzing the proportion of patients who remained in remission at week 40. Remission was defined as a score of 150 or less on the Crohn's Disease Activity Index. RESULTS: Forty patients received methotrexate, and 36 received placebo. At week 40, 26 patients (65 percent) were in remission in the methotrexate group, as compared with 14 (39 percent) in the placebo group (P=0.04; absolute reduction in the risk of relapse, 26.1 percent; 95 percent confidence interval, 4.4 percent to 47.8 percent). Fewer patients in the methotrexate group than in the placebo group required prednisone for relapse (11 of 40 [28 percent] vs. 21 of 36 [58 percent], P=0.01). None of the patients who received methotrexate had a severe adverse event; one patient in this group withdrew because of nausea. CONCLUSIONS: In patients with Crohn's disease who enter remission after treatment with methotrexate, a low dose of methotrexate maintains remission.

Genomewide search in Canadian families with inflammatory bowel disease reveals two novel susceptibility loci.

The chronic inflammatory bowel diseases (IBDs)-Crohn disease (CD) and ulcerative colitis (UC)-are idiopathic, inflammatory disorders of the gastrointestinal tract. These conditions have a peak incidence in early adulthood and a combined prevalence of approximately 100-200/100,000. Although the etiology of IBD is multifactorial, a significant genetic contribution to disease susceptibility is implied by epidemiological data revealing a sibling risk of approximately 35-fold for CD and approximately 15-fold for UC. To elucidate the genetic basis for these disorders, we undertook a genomewide scan in 158 Canadian sib-pair families and identified three regions of suggestive linkage (3p, 5q31-33, and 6p) and one region of significant linkage to 19p13 (LOD score 4.6). Higher-density mapping in the 5q31-q33 region revealed a locus of genomewide significance (LOD score 3.9) that contributes to CD susceptibility in families with early-onset disease. Both of these genomic regions contain numerous genes that are important to the immune and inflammatory systems and that provide good targets for future candidate-gene studies.

Insecure attachment in a subgroup with ulcerative colitis defined by ANCA status.

This study is the first test of the novel hypothesis that perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) marks an etiological division between stress-susceptible and stress-neutral ulcerative colitis. Subjects were 47 UC patients with known p-ANCA status (19 p-ANCA-positive, 28 p-ANCA-absent). Controls were 77 university students. Subjects and controls completed the Reciprocal Attachment Questionnaire. Subjects were categorized as avoidant/nonavoidant and anxious/nonanxious based on scores for compulsive self-reliance and compulsive care seeking, respectively. A higher prevalence of avoidant attachment was present in p-ANCA-absent (58.6%) than p-ANCA-positive subjects (22.2%, chi-square = 5.95, P < 0.02). There was no difference in the prevalence of anxious attachment between p-ANCA-absent and p-ANCA-positive subjects. There was no difference in clinical and psychiatric variables between groups. This finding provides support for a psychobiological contribution to UC in a subgroup identified by the absence of p-ANCA.

Operative and environmental risk factors for recurrence of Crohn's disease.

This retrospective study determined whether a hand-sewn or stapled anastomosis leads to a greater recurrence rate in patients undergoing ileocecal resection for terminal ileal Crohn's disease. The effects of oral contraceptive use, smoking, and age at onset of disease were also examined. Ninety-two patients with Crohn's disease of the terminal ileum whose first operation was an ileocecal resection (terminal ileum and right colon up to but not including the hepatic flexure) were studied for symptomatic and operative recurrence. The symptomatic recurrence rates were 15% at 1 year, 31% at 2 years, and 45% at 3 years. The operative recurrence rates were 6% at 1 year, 14% at 2 years, and 22% at 3 years. The type of anastomosis, whether hand-sewn or stapled, did not affect the rates of symptomatic (P = 0.3) or operative (P = 0.6) recurrence. After the initial resection smoking affected both symptomatic (P = 0.03, risk ratio = 2.380) and operative (P = 0.041, risk ratio = 3.13) recurrence, but there was no effect of age at onset of disease or use of the birth control pill.

Somatostatin-14 modulates acid-dependent inhibition of meal-stimulated gastrin via muscarinic pathways in dogs.

Intraluminal antral acidification inhibits gastrin and stimulates somatostatin-14 (S-14) release, but a functional relationship in the postprandial state has not been established. To examine whether meal-stimulated S-14 mediates inhibition of gastrin release by gastric acid, the effects of omeprazole on circulating levels of S-14 separated from S-28 by gel permeation chromatography, and gastrin were measured without and with atropine in dogs. Compared to controls, pretreatment with omeprazole decreased postprandial plasma levels of S-14 and S-28 (both P<0.01) and increased gastrin (P<0.001). Atropine selectively converted the S-14 response after omeprazole to a peak sixfold increase 40 min after meal ingestion (P<0.001), which was also significantly above S-14 values after atropine alone and controls, but reduced plasma levels of S-28 and gastrin to baseline. Infusions of the somatostatin analogue, cyclo-[7-aminoheptanoyl-Phe-D-Trp-Lys-Thr(BZL)] increased postprandial gastrin twofold above controls (P<0.05), and when administered after omeprazole reversed the inhibition of gastrin by atropine, without altering S-14 levels. In contrast, infusions of S-14, which simulated S-14 levels after omeprazole-atropine, and of [D-Trp8]-S-14, which abolished meal-stimulated S-14 responses, did not alter postprandial elevations of plasma gastrin. This study suggests that in conscious dogs muscarinic inhibitory pathways selectively regulate S-14 secretion, are amplified at neutral gastric pH and reciprocally link S-14 to gastrin secretion in the gastric phase of meal ingestion. Postprandial regulation of gastrin release by S-14 includes neurocrine interactions with muscarinic receptor activation; endocrine or paracrine regulation seem less likely.

Combination ciprofloxacin and metronidazole for active Crohn's disease.

Recent experimental evidence underscores the contribution of intestinal bacteria to the inflammatory process of Crohn's disease. This open study examined the efficacy and safety of combination ciprofloxacin and metronidazole for patients with active Crohn's disease of the ileum and/or colon. Seventy-two patients with active Crohn's disease of the ileum (n = 27), ileocolon (n = 22) or colon (n = 23) were treated with ciprofloxacin 500 mg bid and metronidazole 250 mg tid for a mean of 10 weeks. Clinical remission was defined as a Harvey-Bradshaw index of three points or less; an index reduction of at least three points indicated a clinical response. Clinical remission was observed in 49 patients (68%), and 55 patients (76%) showed a clinical response. A clinical response was noted in 29 of 43 patients (67%) who were not taking concurrent prednisone treatment and in 26 of 29 patients (90%) receiving prednisone (mean dose of 15 mg/day). A clinical response also occurred in a greater proportion of patients with colonic disease, with or without ileal involvement (84%), compared with patients with ileal disease alone (64%), and in patients without resection (86%) compared with those with previous resection (61%). Five patients discontinued antibiotics because of adverse events. After a mean follow-up of nine months, clinical remission was maintained in 26 patients off treatment and in 12 patients who continued antibiotic therapy. Ciprofloxacin in combination with metronidazole is well tolerated and appears to play a beneficial role in achieving clinical remission for patients with active Crohn's disease, particularly when there is involvement of the colon.