Therapy of Inflammatory Bowel Disease, Including Use of Immunosuppressive Agents

Nutritional management of inflammatory bowel disease

The etiology and specific treatment of Crohn's disease and ulcerative colitis are unknown, and the treatment strategy for patients with inflammatory bowel disease is essentially symptomatic and supportive. The malnutrition that frequently accompanies inflammatory bowel disease is a manifestation of intestinal failure and should be vigorously corrected with total parenteral nutrition, elemental diets, or both. Evidence exists for the value of total parenteral nutrition and elemental diets as primary therapy for inflammatory bowel disease in selected patients. Judicious nutritional therapy remains a cornerstone in the adjunctive management of these patients.

Anovaginal and rectovaginal fistulas in Crohn's disease

Between 1957 and 1985, 886 women with Crohn's disease and an intact distal large bowel were seen at St. Mark's Hospital. Ninety of these patients developed a fistula between the vagina and anus or rectum at an average age of 34 years. The track of the fistula was clearly documented in 80 patients and was extrasphincteric or suprasphincteric in 36, transsphincteric in 42 (high 13, low 29), and superficial in two. Of the 90 patients, 12 (13 percent) were managed throughout without recourse to surgery. Twelve (13 percent) had the fistula laid open or drainage of an abscess as the only surgery. Twelve (13 percent) underwent repair of the fistula and, of these, eight remain symptomatically cured. One has had further symptoms but no surgery while three later underwent proctectomy for rectal disease. In eight patients the colon was removed and the rectum defunctioned and in 34 the rectum was excised as the initial surgery after development of the fistula. The remaining 12 (13 percent) underwent later proctectomy for rectal disease or failed conservative management of the fistula. Extensive colonic involvement, rectal disease, or associated anal lesions were the main reasons for rectal excision in 38 patients. In only ten was the rectovaginal fistula a prominent indication for proctectomy. As medical treatment, repair, or other local surgery were successful in one third of the patients, these options should always be considered in the first instance.

Comparison of total parenteral nutrition and elemental diet in induction of remission of Crohn's disease. Long-term maintenance of remission by personalized food exclusion diets

Total parenteral nutrition or elemental diet can be used to induce remission of Crohn's disease. A randomized study has been conducted of 36 patients to assess the relative efficacy of the two techniques used without pharmacologic support; both were successful, and no significant differences emerged in the number of days to remission or the mean changes in Crohn's disease activity index, erythrocyte sedimentation rate, or serum albumin. The elemental diet is cheaper, simpler and safer. Uncontrolled clinical experience with 77 patients showed that personalized food exclusion diets were associated with an average annual relapse rate of only 11% for the first five years of diet alone; there have been six pregnancies and the longest remission is now 75 months. The use of elemental diet followed by the development of a personal food exclusion diet appears to be an effective long-term therapeutic strategy for Crohn's disease.

Crohn's disease: maintenance of remission by diet

20 patients with Crohn's disease took part in a controlled trial in which remission was maintained by either an unrefined carbohydrate fibre rich diet or a diet which excluded specific foods to which a patient was intolerant. 7 out of the 10 patients on the exclusion diet remained in remission for 6 months compared with none out of the 10 on an unrefined carbohydrate fibre rich diet (p less than 0.05, Fisher's exact test). In an uncontrolled study an exclusion diet allowed 51 out of 77 patients to remain well on the diet alone for periods of up to 51 months, and with an average annual relapse rate of less than 10%.

Favorable effect of 6-mercaptopurine on fistulae of Crohn's disease

Fistulae are distressing chronic complications of Crohn's disease which have served as one of the most common indications for surgical resection. While steroids and sulfasalazine have not been successful in closing fistulae, in a previous double-blind study 6-mercaptopurine (6-MP) was more effective than placebo in accomplishing this goal (31% vs 6%). Thirty-four patients with Crohn's disease fistulae were treated with 6-MP for a minimum period of 6 months. In 13 patients (39%) the fistulae closed completely, and in another 9 (26%) there was obvious improvement. All types of fistulae responded to 6-MP with the most impressive closures occurring in patients with fistulae of the abdominal wall and enteroenteric fistulae. The mean time to respond was 3.1 months, with 23% of patients taking longer than 4 months to show any response. Response was not related to other drugs (steroids, sulfasalazine) used in conjunction with the 6-MP. The site of intestinal involvement with Crohn's disease did not appear to play a significant role in the frequency or degree of response to 6-MP, but patients without prior resection and fistulae did better than those with fistulae occurring after surgery. The long-term response to fistulae was good if 6-MP was maintained, whereas exacerbation eventually followed discontinuation of 6-MP. 6-Mercaptopurine is an effective and useful drug in the treatment of fistulae, as it is in other manifestations of chronic unrelenting Crohn's disease.

Drug therapy of inflammatory bowel disease

Although the etiology of inflammatory bowel disease is unknown and specific therapy is unavailable, enough information on existing empiric agents is available to allow rational therapy. These agents include sulfasalazine, steroids, immunosuppressive drugs, metronidazole and cholestyramine. Sulfasalazine is a two-part molecule that depends on bacterial cleavage in the colon to deliver locally acting 5-aminosalicylate, whose mechanism of action may relate to inhibition of prostaglandin synthesis. The other half of the molecule, sulfapyridine, is responsible for most of the side effects of the drug. While the efficacy of sulfasalazine in the treatment and prevention of attacks of ulcerative colitis is well established, its use in Crohn's disease appears to be limited to patients with active colitis and ileo-colitis. Sulfasalazine is of major benefit in preventing relapses in patients with ulcerative colitis in remission. New formulations of 5-aminosalicylate may allow delivery of the apparently active moiety to the small bowel and colon without concomitant sulfapyridine toxicity. Corticosteroids are highly effective in acute attacks of ulcerative colitis and Crohn's ileitis and ileo-colitis; the mechanism of antiinflammatory action remains speculative. However, maintenance therapy with steroids is ineffective in preventing relapses or recurrent attacks of either ulcerative colitis or Crohn's disease. Steroid enemas allow topical administration to patients with distal colitis and proctitis with few systemic side effects. In children with growth failure associated with active Crohn's disease, amelioration by steroid therapy may actually restore normal growth. Immunosuppressive agents such as azathioprine and 6-mercaptopurine are of little value in active Crohn's disease when administered alone; however, in combination with other agents they may help diminish steroid dose, close fistulae and prevent relapse. Their mode of action likely depends on long-term cytostatic effects on immune effector cells. Concern for leukopenia and the development of late malignancy has limited their use to patients not responding to other therapies. Metronidazole, an antimicrobial agent that is effective against anaerobes, has recently been shown useful in Crohn's disease involving the colon and perianal area. Its mechanism of action is uncertain, but may be related to its antibacterial actions on anaerobes. Cholestyramine can be successfully used to control bile salt-induced diarrhea in Crohn's patients with terminal ileal resections. Effective drug therapy of inflammatory bowel disease is only part of a total program of management including reassurance, frequent explanation, well-timed use of surgery, and an understanding physician.

Retrograde colonic spread of sulphasalazine enemas

In five patients with inflammatory bowel disease and in two healthy control subjects retrograde spread and colonic distribution of rectally introduced sulphasalazine (SASP) enema were investigated. The SASP enema was labeled with 99mTc and imaged by a gamma camera. In all patients the SASP enema reached the inflamed portion of the colon. From 73% to 84% of the total SASP enema were fairly homogeneously distributed beyond the patients' rectum. The results suggest that patients with inflammatory bowel disease may benefit from SASP enemas even if the total colon is involved.

Immunohistochemical evaluation of carcinoembryonic antigen, secretory component, and epithelial IgA in tubular and villous large-bowel adenomas with different grades of dysplasia

In a material of 513 consecutively collected large-bowel polyps, tubular and villous adenomas with corresponding histologic grades of epithelial dysplasia were selected. Fifty-two samples of the former and 27 of the latter category were evaluated semiquantitatively for immunohistochemical staining of the epithelial marker proteins carcinoembryonic antigen (CEA), secretory component (SC), and IgA. No consistent differences in the overall staining properties were found between the two types of tumours. In both categories the staining intensity for SC and epithelial IgA decreased with increasing degree of dysplasia, most strikingly so for IgA. This observation shows that the malignant alterations impair the capacity of the columnar epithelium to produce SC and to express it as a functional receptor mediating uptake of dimeric IgA. Thus, the absence of epithelial IgA in large-bowel adenomas may be a useful adjunct in grading of dysplasia. Conversely, the presence of CEA did not seem to be related to dysplastic alterations in the epithelium.